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核心素养导向下初中化学心智模型的测评——以“质量守恒定律”为例
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作者 欧廉 杨发福 +1 位作者 高兴远 刘振威 《化学教学》 CAS 北大核心 2023年第10期12-16,共5页
基于《义务教育化学课程标准(2022年版)》提出的化学观念和科学思维核心素养,采用二段式纸笔测验和半结构访谈的方法,分别围绕质量守恒定律的概念、质量守恒的原因、化学方程式表示的意义、质量守恒定律的应用等4个维度对初三学生持有... 基于《义务教育化学课程标准(2022年版)》提出的化学观念和科学思维核心素养,采用二段式纸笔测验和半结构访谈的方法,分别围绕质量守恒定律的概念、质量守恒的原因、化学方程式表示的意义、质量守恒定律的应用等4个维度对初三学生持有的“质量守恒定律”心智模型进行测评,根据学生的知识缺陷归纳9种缺陷模型,并提出相关教学建议,促进学生化学观念和科学思维核心素养的发展。 展开更多
关键词 初中化学 化学观念 科学思维 质量守恒定律 心智模型
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基于多参数优化的某后扭力梁设计 被引量:1
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作者 杨发富 赵云 《中国汽车》 2022年第3期48-54,共7页
首先构建了某后扭力梁有限元模型,并对其进行强度、扭转刚度、模态分析,结果表明,初始结构的后扭力梁U字形截面横梁有一个强度工况不达标,扭转刚度及弯曲模态均不满足目标要求。然后以5个料厚参数为设计变量,以扭转刚度及模态为响应,进... 首先构建了某后扭力梁有限元模型,并对其进行强度、扭转刚度、模态分析,结果表明,初始结构的后扭力梁U字形截面横梁有一个强度工况不达标,扭转刚度及弯曲模态均不满足目标要求。然后以5个料厚参数为设计变量,以扭转刚度及模态为响应,进行灵敏度分析,发现U字形截面横梁料厚为扭转刚度及弯曲模态的主要影响因素。即识别出U字截面横梁为强度、扭转刚度及模态的薄弱及敏感区域。针对U字形截面横梁采用Morph方法进行参数化建模,构建4个截面形状参数、1个截面位置参数及1个料厚参数,以不达标的强度工况及扭转刚度及模态为约束,以质量最小为目标,应用Optimus采用差分进化优化算法对后扭力梁进行优化,得到了最优设计方案。经验证,其强度、模态及扭转刚度均满足目标要求,最终达到了重量与性能的平衡。 展开更多
关键词 后扭力梁 参数化建模 MORPH 多参数优化
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Synthesis and Dyes Adsorption Properties of Calix[4]crown-grafted Chitosan Chelating Polymer
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作者 FANG Xiaoting GUO Hongyu +1 位作者 yang fafu BAI Xiaoyan 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2015年第6期1051-1055,共5页
By the Schiff-base condensation of formacyl calix[4]crown(2) with raw chitosan, a novel calix[4]crown- grafted chitosan chelating polymer(3) was conveniently prepared in good yield. The structure of polymer 3 was ... By the Schiff-base condensation of formacyl calix[4]crown(2) with raw chitosan, a novel calix[4]crown- grafted chitosan chelating polymer(3) was conveniently prepared in good yield. The structure of polymer 3 was con- firmed by elemental analysis, infrared(IR) spectrometry and X-ray diffraction(XRD) analysis. The elemental analysis suggests that the grafting degree of calixcrown unit was 22% on the amino groups of chitosan. The morphological characteristic of polymer 3 was studied by scanning electron microscopy(SEM). Polymer 3 possessed loose porous and smooth morphology of surface. The dyes adsorption abilities of polymer 3 for a series of organic dyes[Orange I(OI), Neutral red(NR), Victoria blue B(VB) and Brilliant green(BG)] were studied by solid-liquid adsorption expe- riments. The adsorption percentages increased from 45%-60%(raw chitosan for dyes) to 75%-90%(polymer 3 for dyes). The highest adsorption percentage reached 89% for VB. The saturated adsorption capacities for OI, NR, VB and BG were as high as 622, 564, 854 and 781 mg/g, respectively. The adsorption abilities kept stable at 70%-90% in the scope of pH=5-9. The adsorption abilities for anionic dye(OI) decreased gradually with the increase of pH and the opposite trend was observed for cationic dyes(NR, BG, VB). The adsorption percentages were 70%--90% after five times' cycles for adsorption. 展开更多
关键词 CALIXCROWN CHITOSAN ADSORPTION DYE
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Design, Synthesis and Properties of Novel C60-Crown Dyads by 1,3-Dipolar Cycloaddition
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作者 DI Xingdong YE Jinqi +2 位作者 yang fafu GUO Hongyu YAN Xiaoyun 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2014年第2期242-244,共3页
Based on the 1,3-dipolar cycloaddition of azomethine ylide generated in situ from aldehyde and sarcosine attached to C60,two novel benzo-15-crown-5/C60 dyads with a different linking chain in each were designed and sy... Based on the 1,3-dipolar cycloaddition of azomethine ylide generated in situ from aldehyde and sarcosine attached to C60,two novel benzo-15-crown-5/C60 dyads with a different linking chain in each were designed and synthesized in yields of 30% and 38%,respectively.It was found that their UV-Vis absorption spectra could be regulated hypsochromically by metal ions complexed.The long and soft linking chain was favorable for cooperate interaction of crown ether unit and C60 unit. 展开更多
关键词 C60 Benzo-15-crown-5 1 3-Dipolar cycloaddition COMPLEXATION
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