“废旧电池污染”研究性学习的实施与反思

结合指导学生开展“废旧电池污染”的研究性学习案例,探索了创设多样化的研究性学习的教学情境、实践活动和校本课程从而激活化学课堂的途径,并就中学化学教学与研究性学习的整合进行了反思。     

核心素养为本的实验课堂“异常状况”教学策略

结合具体教学实例，阐述了如何利用化学实验课堂中“异常状况”的发生，抓住教学契机，顺“势”而为。通过创设真实且富有价值的问题情境，进一步激发学生学习兴趣，通过师生互动，创造“灵活动态”的化学课堂。在具体教学策略实施分析的案例中，预设课堂可能的“异常状况”,通过“实验探究”,提高学生对复杂情境的认知能力；面对课堂偶发的“异常状况”,通过“多角度辨析”,增强学生对复杂体系的分析能力；基于课堂典型的“异常状况”,通过“进阶式实验探究”,提升学生对复杂问题的处置能力。对“异常状况”处理的过程中，注重化学知识结构化，认识思路结构化，关注学生的认知发展规律，注重情境、活动和问题解决的整体设计，突出学生学习方式的转变，促进学生化学学科核心素养的形成和发展。     

《梦溪笔谈》融入中学化学教学的探索

尝试将《梦溪笔谈》融入中学化学教学,将该著作中《巫咸河》《沈卢鱼肠》《石油》《胆矾炼铜》与胶体、合金、石油的分馏、置换反应等化学知识结合,以问题情境导入和试题编制等形式,帮助学生理解化学知识,培养综合素质,“润物细无声”地传承优秀传统文化。     

基于元认知理论的化学实验教学策略

实验是化学学习中获取知识、培养创新思维和实践能力的主要渠道。把元认知理论应用于化学实验教学实践来指导学生的学习可以解决“如何教会学生学习”及“如何提高元认知能力”等问题。对在化学实验教学中如何提高学生元认知水平提出了几点教学策略,以期元认知理论能与化学实验教学真正结合,对培养学生全面发展产生积极的影响。     

“卤代烃——溴乙烷”教学设计

1指导思想与理论依据本节课教学指导思想:根据普通高中化学课程标准提出的"通过以化学实验为主的多种探究活动,使学生体验科学研究的过程,激发学习化学的兴趣,强化科学探究的意识,促进学习方式的转变,培养学生的创新精神和实践能力”的理念,以学生为主体,让学生自主地参与知识的获得过程,并给学生充分的表达自己想法的机会。     

中学化学实验发展性教学模式的构建

根据“以学生为主体,以学生发展为本”的指导思想,构建中学化学实验发展性教学的模式,使化学实验教学活动成为增强学生主体参与意识,培养学生发现问题、解决问题、学会创新,促进学生潜能和个性发展的学习活动,开辟化学学科中实施素质教育的新途径。     

“碳达峰碳中和”中的无机化学问题探究——PBL教学实践

依托国家级一流本科课程，融合PBL (Problem-Based Learning)开展混合式课堂教学，设计了PBL教学案例——“碳达峰碳中和”中的无机化学问题探究。引导学生从大气中CO₂污染产生的化学反应过程入手，分析基于降低碳排放开发的CO₂转化新技术的化学反应原理，探讨不同CO₂转化技术的优势和劣势。通过PBL教学实践，将化学理论与工业实践深度融合，在夯实理论基础的同时，使学生的学习能力和解决问题能力得到提升。通过思政教育有机融入，使学生了解到我们国家科技的进步，体现课程教学的立德树人。     

化学教学中应如何培养学生的问题意识

当前,中学生问题意识较差,不能发现并提出问题。这种状况不能适应新课程改革的需要。笔者总结自己在化学教学中培养学生问题意识的几种做法：唤醒“问”的意识,使学生想问;营造“问”的氛围,使学生敢问;创设“问”的情境,使学生能问;传授“问”的技巧,使学生会问;教师要正确面对学生的提问。     

加强实验教学 启发学生积极思维

化学实验是化学教学的重要组成部分,加强实验教学,启发学生积极思维,有助于提高中学化学教学质量。一、培养学生正确的学习方法学习化学要通过认真做实验,精心观察实验现象,获取感性材料,再通过分析思考,使认识产生飞跃,掌握化学概念,学习化学理论,也就是要运用实践、认识、再实践、再认识的方法。     

新课程背景下化学科学探究活动的设计和评价

本文研究新课程背景下科学探究活动的设计和评价,探索网络环境下,“空气污染的成因与防治”科学探究活动的实施。通过创设“问题情境、任务驱动、自主探究、解释与结论、协作与交流、反思与评价”六个教学环节实施科学探究活动。并对科学探究活动作过程性、综合性、发展性、多元化的评价,有利于激发学生科学探究的兴趣,培养学生科学探究意识、协作精神、创新精神和实践能力,提高学生信息素养和科学探究能力。     

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%.     

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.     

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.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.