基于信息加工模拟结构的化学教学实践研究

介绍了美国心理学家加涅运用信息加工理论模拟学习过程的结构,"多元智能"的含义,"问题连续体"理论的5种问题类型,以及在化学教学设计过程中,根据学生的智力发展水平构建5个层次的问题类型以开展教学设计.实验研究证明,实验前后学生的学习成绩、学习兴趣、学习注意力、思维能力、互动效果存在显著差异(P<0.01);采用"问题连续体"教学模式进行教学,学生在探究实验的过程中知识得到深化,思维得到升华,发展了学生的多元智能,发散思维,探索、创新、实践等能力.     

仪器分析发展史在大学教学中的应用探讨

在大学仪器分析教学过程中 ,通过讲授仪器分析发展史 ,培养学生的创新能力 ,激发学生学习该课程的热情 ,使学生能更好地掌握基础原理与实验技能。介绍了仪器分析发展史在本科教学中的几种讲授方式     

认识规律──启发式教学──培养能力

中学化学教学大纲在教学目的中提出培养和发展学生的能力,在教学要求中指出逐步培养和发展学生的观察能力、思维能力、实验能力和自学能力,要重视科学方法的教育,注意培养学生的创新精神。     

全媒体时代仪器分析实验课程的教学改革研究

随着现代信息技术的迅猛发展,声音、图像、视频等多种媒体在课程教学中广为应用,学生在任何时间、任何地点利用信息终端完成线上自主学习成为常态,课程教学的信息全媒体时代随之而来,全媒体对实验教学带来全新要求。本文在总结近年来仪器分析实验全媒体教学经验的基础上,开展全媒体时代背景下仪器分析实验的实践教学设计、资源库建设、新型教学模式构建、课堂教学考评、教学团队建设的研究,以期提高学生自主综合学习能力和高阶思维能力,提升仪器分析实验课程的教学效果,为深入开展全媒体教学改革提供参考。     

固相萃取技术在水果氨基酸分析前处理中的应用——一个仪器分析综合实验

为提高学生的理论水平和实践能力,设计了针对欧李果实氨基酸测定的仪器分析综合实验。引入样品分析前处理环节,构建完整的仪器分析过程。通过氨基酸提取方法比较及固相萃取技术在氨基酸净化过程的方法探索,有效促进学生理论知识和实践能力的融合,在解决实际问题的过程中提升学生的科学素养及综合思维能力。     

论物质鉴别教学中学生创造性思维能力的培养

教师在教学中应当十分抓紧抓好学生学习心理中创造性思维的素质训练,从而达到培养和发展其创造性思维能力之目的。本文结合有关物质鉴别课题的教学实际,谈谈如何加强学生创造性思维能力的培养。     

高分子化学课程教学中的辩证思维

高分子化学是高分子学科重要的基础课程,在课程教学过程中培养学生的辩证思维能力,使学生学会用对立统一和发展变化的眼光看待问题,对提高学生的科研和技术开发能力至关重要。教师在授课过程中应运用辩证思维的方法,深入发掘课程内容中的思想精髓,同时充分利用文献资源中体现出来的思想方法,与课程内容广泛联系,引导学生进行深入讨论,使学生养成从不同角度全面深入思考问题的习惯,提高发现问题和解决问题的能力,逐步形成科学思维能力。     

比较教学法在仪器分析实验教学中的应用

仪器分析实验是化学及相关专业的重要实验课程。结合课程特点和培养目标,提出了将比较教学法融入课堂的教学方法,指出了意义和作用,介绍了教学中开展比较教学的实践与应用。该方法加强了学生对仪器功能特点的掌握,激发其实验兴趣和创新精神,学生的认知能力在比较过程中不断建构、丰富、提高和发展,取得了较好的效果。     

仪器分析课程教学与实验改革

结合应用化学专业学生的学习特点,对仪器分析课程教学与实验过程进行了改革尝试。     

浅谈中学化学实验仪器的规范教学

以“蒸馏烧瓶”这一仪器名称的误答情况展开分析,对必修教材中化学实验仪器的呈现方式进行统计与比较分析,深入调查学生对于化学仪器掌握的情况,从而引发改进中学化学实验仪器教学的思考。     

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.     

Copper catalyzed/mediated synthetic methodology for ebselen and related isoselenazolones

Scope of the copper catalyzed/mediated selenium-nitrogen coupling reaction has been studied for the synthesis of isoselenazolones. It is noticed that the 2-chloro, 2-bromo-, and 2-iodo-aryl amides substrates can be exploited in the selenium-nitrogen coupling reaction by employing 25-100 mol % of CuI/1,10-phenanthroline (L) and potassium carbonate as a base in DMF. Furthermore, electron rich 2-chloro-arylamides also underwent selenium-nitrogen coupling reaction to give biologically important selenium-nitrogen heterocycles. Also, copper-catalyzed selenium-nitrogen coupling reaction has been meticulously applied for the synthesis of diaryl diselenides having methoxy, amine, and amide functionality from respective aryl iodides in the presence of stoichiometric amount of succinimide as an external Se-N coupling partner.