共查询到20条相似文献,搜索用时 296 毫秒
1.
2.
3.
“大学化学”课程在大类培养中起到塑造学生化学科学素养的重要作用。根据“新工科”的要求和大班化授课的特点,提出采用角色代入法进行“大学化学”课程的授课,利用角色激发学生学习化学的主动性,开启良好的师生互动,建立以学习共同体为导向的高效课堂。 相似文献
4.
5.
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。 相似文献
6.
7.
针对大学本科一年级基础化学如“化学概论”等课程教学中,学生对于不断出现的专业名词及物理化学含义的理解问题,以“焓”“熵”等外来词汇以及角动量l、能级分裂单位“Dq”等缩写为例,从专业名词来源开始讲解,使学生在学习过程中既知其然又知其所以然,更好地理解化学专业词汇,尤其是外来词汇的内涵与物理化学意义。 相似文献
8.
采用“中学化学课堂环境问卷”作为研究工具,对深圳市、长春市、佳木斯市等3个地区的4所高中861名学生的化学课堂环境进行调查,并进行差异分析。研究结果表明,高中生对化学课堂环境的总体感知较好,7个维度中“学生凝聚力”“平等”“任务取向”“合作”等4个维度的平均分大于3.4,“教师支持”和“参与”维度的平均分在3.0~3.4,只有“探究”维度的平均分小于3.0。城市高中生对课堂环境的感知明显好于乡镇高中生,学生心目中所期待的化学课堂比实际的化学课堂更积极。 相似文献
9.
10.
论证教学是当前国际科学教育教学的热点领域。论文采用准实验设计,使用混合研究方法,在“化学教学论实验”课程中对学生进行了为期一学期的教学实践过程。实验组开展论证式教学的实践活动,并采用GR编码方式细致地分析学生科学论证活动的过程。研究结果表明,论证教学可以显著提高化学师范生的科学论证能力,并提高化学实验课程的学习兴趣。 相似文献
11.
Uroš Grošelj Mojca Žorž Amalija Golobič Branko Stanovnik Jurij Svete 《Tetrahedron》2013,69(52):11092-11108
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
12.
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
13.
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
14.
Shashikant U. Dighe Surya K. Samanta Shivalinga Kolle Sanjay Batra 《Tetrahedron》2017,73(17):2455-2467
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones. 相似文献
15.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates. 相似文献
16.
Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described. 相似文献
17.
用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在. 相似文献
18.
19.
Jona Mirnik Eva Pušavec Kirar Sebastijan Ričko Uroš Grošelj Amalija Golobič Franc Požgan Bogdan Štefane Jurij Svete 《Tetrahedron》2017,73(24):3329-3337
A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu0 as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than CuI in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT). 相似文献
20.
George E. Magoulas Thomas Garnelis Constantinos M. Athanassopoulos Dionissios Papaioannou George Mattheolabakis Konstantinos Avgoustakis Dimitra Hadjipavlou-Litina 《Tetrahedron》2012,68(35):7041-7049
(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C60, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine. 相似文献