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1.
冀楠  王海波  秦向阳  兰婷  何炜 《化学教育》2019,40(16):71-74
概述了问题导向式的研究型教学设计在医科院校"医用有机化学"课程中有机波谱分析章节的应用情况。该部分内容具有学生"难学" "难考" ,教师"难教"的教学特点。基于此,通过层层设问、循序解答的授课方式,结合丰富的应用示例,进行有机波谱分析核心概念(绪论)的理论教学。结果表明,该教学方法可有效提高学生学习兴趣,降低学习难度,使学生在有限的学时内掌握有机波谱分析的基础理论与核心概念,为后续识谱、解谱能力的培养夯实基础。  相似文献   

2.
“先进纤维材料”是我校高分子材料与工程专业的一门专业课程,在培养高分子材料专业技术人才方面起着重要的作用。在互联网高度发达的今天,将基于Canvas教学平台的混合式教学引入“先进纤维材料”教学过程中,把常规的面对面课堂教学与网络教学的优势充分结合,激发学生对专业知识的学习兴趣,加深对所学内容的理解和记忆。同时,为了将教学内容变得更生动形象,针对每一章节重难点录制微课并在其中插入更加直观的视频动画,上传至Canvas教学平台,供学生在课前对所学内容进行自主学习,提高学生自主学习和个性化学习能力。  相似文献   

3.
黄肇锋 《化学教育》2015,36(16):50-53
将翻转课堂教学模式引入到化学证考试辅导中,实践表明,学生对翻转课堂的接受程度很高;学生认为教师提供的教学视频对其课前学习是有用的;学生基本在课前能主动完成课前学习任务和在课中适应课堂学习活动。在较短的辅导时间内,学生对翻转课堂教学模式应用在技能操作辅导中的适应能力大于理论辅导。  相似文献   

4.
刘国杰  李晓娜  马勇 《化学教育》2016,37(10):60-62
选取医学基础化学课程中的2个章节,组织PBL-TBL-CBL组和LBL组进行教学实验,通过成绩考核、教师评价和问卷调查进行教学效果评价,探讨PBL-TBL-CBL整合模式在医学基础化学课程中理论和实验教学上的应用。通过对比分析,证实PBL-TBL-CBL整合模式教学可以充分调动学生的积极主动性,增强自学和团队合作能力,提高实验操作技能,准确掌握教学大纲要求的知识点,提升学生对化学学习的乐趣和自信。建议对基础化学的部分章节采用PBL-TBL-CBL整合模式教学,同时结合LBL传统教学共同来完成大纲要求的教学任务。  相似文献   

5.
刘钢  朱万春 《化学教育》2016,37(20):31-34
结合物理化学基础实验自身特点,尝试将翻转课堂教学模式引入物化实验教学,详细分析了微课制作、课堂组织和教学评价等诸多环节。该教学模式可以有效地调动学生的学习主动性,使学生成为教学主体,有效地发挥基础实验在物理化学教学中的积极作用。  相似文献   

6.
郭雪红 《化学教育》2017,38(6):38-42
鉴于高职高专基础化学实验教学中存在的客观问题,将微课引入到传统教学中。介绍了微课在“药用基础化学实验技术”课程中的应用,并以“EDTA标准溶液的配制、标定及葡萄糖酸钙含量的测定”为例说明了微课的设计思路。教学效果表明:学生可以很快掌握学习方法,理清学习内容,增强了自信心,真正实现了“我爱学”的良性发展。  相似文献   

7.
微课是在信息化时代和新教学理念下提出的新型教学模式,针对无机化学实验教学的现状,利用微信公众号构建微课平台,辅助教师进行课堂教学,解决了无机化学实验教学中安全培训、学生预习、学时少及实验内容多、实验药品购买使用受限、不能做有毒实验等问题。通过微课教学还实现了实验内容多样化、演示操作可视化,从而提升学生学习的主观能动性,增强动手能力,规范实验操作流程,便于学生对实验重点难点的掌握,同时增强师生交流,满足各层次学生要求,提高课堂效率。  相似文献   

8.
通过QQ分屏与学习通结合,叙述了化工原理课程线上授课全过程。详细介绍了课前准备、线上授课模式以及平台使用技巧,针对教学中的重点问题以及学生提出的问题给出详细的处理方案。能够帮助零基础的教师快速实现在线教学,为广大线上教学教师提供备选方案。  相似文献   

9.
基于"前置性学习",课前建立教师与学生交流的平台,为教师更有效地进行课堂教学提供基础。结合"硝酸的性质"教学,阐述了"前置性学习"在元素化合物教学中课前如何设计、课中的如何延伸和拓展,最终实现学生乐学、好学的好课。  相似文献   

10.
陈美慧  陈燕 《化学教育》2019,40(5):46-49
对X市部分高中化学教师进行了微课教学能力提升需求的调查研究。结果表明高中化学教师学习与应用微课视频的意愿较高,但也存在着对微课概念把握不清、微课视频制作能力欠缺等问题,并就此提出培训建议。  相似文献   

11.
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%.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

16.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

17.
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.  相似文献   

18.
Siqi Li  Xingpeng Chen  Jiaxi Xu 《Tetrahedron》2018,74(14):1613-1620
Microwave-assisted copper-catalyzed ring expansions of three-membered heterocycles with α-diazo-β-dicarbonyl compounds were investigated. Thiiranes generated 3-acyl-5,6-dihydro-1,4-oxathiines in the presence of copper sulfate and trans-3-acyl-5,6-dihydro-1,4-oxathiines as stereospecific products for 1,2-disubstituted cis-thiiranes through an intramolecular SN2 process. Oxiranes gave rise to 2-acyl-5,6-dihydro-1,4-dioxines under the catalysis of copper hexafluoroacetylacetonate and cis-3-acyl-5,6-dihydro-1,4-dioxines as stereospecific products for 1,2-disubstituted cis-oxiranes via an intimate ion-pair mechanism. The current method provides a direct and simple strategy in efficient preparation of 3-acyl-5,6-dihydro-1,4-oxathiines and 2-acyl-5,6-dihydro-1,4-dioxines, important agents in medicinal and agricultural chemistry, from readily available thiiranes and oxiranes, respectively.  相似文献   

19.
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.  相似文献   

20.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

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