利用手持技术数字化实验促进学生对焰色反应概念的认知*

针对焰色反应教学存在的不足,以手持技术TQVC概念认知模型为理论依据,从“混合、定量”的角度出发,设计手持技术数字化实验以促进学生对焰色反应概念的认知。利用分光光度计传感器,通过测定火焰发射光谱的波长和光强度,从定性和定量2个方面检测混合液中的NaCl和KCl,帮助学生从宏观和微观相结合的视角认识焰色反应的本质。     

“思想实验”的价值及在实验教学中的实践路径*

对“思想实验”的发展历程及其在科学和技术创新活动中的意义进行了综述。提出了将“思想实验”与化学实验教学结合的启发式教学策略,优化了现行的化学实验教学流程。采用引导学生对实验步骤的设计思路进行反向逻辑推理和分析的教学方法,能够提升学生的创新思维和创新实践能力。     

以实验和论证为杠杆撬动化学概念深度学习*——以“分子与原子”教学为例

以倡导“理解与批判、联系与构建、迁移与应用”的深度学习为理念,围绕“分子与原子的概念”比较教材与文献的设计思路,调整认知脉络,着力解决“概念学习过程中实验探究少,宏观现象进入微观分析的相关实验不匹配,忽略证据推理、变化观念与平衡思想核心素养”等不足。设计“3种形态的碘与淀粉的反应、H2O2溶液与品红反应、H2O2溶液的分解反应”3组实验,设置学生画分子模型、画H2O2分子分解的微观过程等活动,提炼“物质种类、分子种类、物质性质之间的关系是什么？你从实验中找到哪些证据支持观点？前2个单元的实验,还有哪些可作为论证的依据？”等问题,引发学生充分论证。“实验、活动、问题、论证”环环相扣,促成教学内容的有效结构化,通过化学概念的深度学习实现化学学科核心素养的发展。     

化学青年教师实验素养的问题表现与提升路径—基于 2020年江苏省高中化学青年教师教学基本功大赛

江苏省高中化学青年教师教学基本功大赛突出了对教师实验素养的考查。大赛中对教师实验素养考查的内容有6个项目。通过观摩大赛,发现部分选手实验素养较弱,表现在化学实验安全知识“口是心非”,化学基础原理知识“似是而非”,化学实验内容设计未能体现“以生为本”,化学实验操作未能“精益求精”。分析青年教师实验素养问题的原因,提出青年教师实验素养提升的路径有:落实教师实验素养提升培训活动,开展实验创新研讨活动,突出基于实验内容的教学设计。     

手持技术数字化实验支持下的“盖斯定律”认知*

在“多重转化、比较建构”认知模型指导下,利用手持技术数字化实验和改进装置,在中学化学教材中“中和热的测定”实验的基础上进行拓展设计,用温度传感器测量3个变化过程的反应热:强碱固体溶解于水、强碱固体与稀盐酸反应以及强碱溶液与稀盐酸反应,并基于“四重表征”理论进行分析,实现对“盖斯定律”的验证,促进对“盖斯定律”的内涵认知。克服了操作烦琐、可视性不佳、实验误差大等问题,有助于在教学中渗透化学核心素养。本研究是对教材内容的补充和拓展,为教师进行“盖斯定律”教学实践提供一定参考。     

对适应性高考试题中“真实性实验问题”的探讨及教学建议*

节选了部分适应性高考题中的“真实性实验问题”进行分析和探讨,解释了相关实验现象,运用“数学关系式”对相关图像的数据进行了比较分析,并提出了相关的教学建议。“真实性实验问题”是“真实情境”试题的来源之一,针对试题、教材、教学中的“真实性实验问题”进行定位和比较,为落实以“化学学科核心素养”为命题原则的新高考做好铺垫和引导作用。     

“双一流”背景下化学本科人才培养创新路径探索*

人才培养是高校的核心使命和必然要求。在“双一流”建设背景下,国家对高校人才培养提出了新要求。西北大学化学与材料科学学院围绕“培养什么人”“怎样培养人”,对本科人才培养不断进行探索和创新,搭建 “以本科生导师制为核心”的科研训练体系,“以拓展学术视野为核心”的国际化培养体系,“以调动教师教学投入为核心”的评价激励体系,“以提升创新意识为核心”的实践育人体系等措施,实现高校理科人才培养的创新发展。     

化学实验“三三三”翻转教学模式的探索与实践*

针对当前化学实验翻转课堂教学模式中存在的不足,依托“云班课”,重构了以学生为中心的化学实验“三三三”翻转教学新模式,即将实验教学划分为“三个课堂”:自学课堂、理论课堂和实验课堂等;理论课堂里包含“三个环节”:个人汇报、小组活动和测试点评等;学习效果评判有“三个评价”:自学评价、参与评价和动手评价等。以有机化学实验中“环己烯的合成”为例,采用该新的教学模式开展了教学活动,整个教学过程不仅体现了“以学定教、学生为中心”的教学理念,而且也能发挥出线下传统课堂的优势,实现了将“知识内化”的时间拉长,达到对学生线上自学“知识传授”掌握度的有力检验的目的,更有时间和空间进行课程思政元素的挖掘与融入,完成在知识传播中实现对学生的价值引领。     

“三全育人”视阈下高校学科导论课程育人路径研究——“化学与社会”课程的问卷调研

以吉林大学化学学院开设的“化学与社会”课程为例,介绍学科导论课程“三全育人”初衷,探究学科导论课程“三全育人”路径。坚持内容为王,挖掘育人资源,创新教学方式,以期将思想政治工作融入学科导论课程各环节,助力“三全育人”综合改革。     

基于交叉优势特色学科的大学化学创新实验教学体系构建与实践*

以大学化学与农林优势学科交叉融合为教学改革任务,构建“基础+模块”的大学化学实验创新教学体系,分别开展“项目式”教学、“科教融合”教学、“产学研”教学、“混合式”教学、“虚实结合”教学等五位一体的实验教学实践,并建立化学创新实验课程评价新体系。本化学创新实验教学体系改革明显提高了学生的实践动手能力与综合素质,为深入开展化学基础学科与农林优势学科交叉融合教学奠定一定基础。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.