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1.
针对实验化学课程的特点,探讨了实验化学“课前知识传递,课堂知识内化,课后反思提高”的翻转课堂教学设计。以“硫酸亚铁铵的制备”为实验案例,通过翻转课堂在学习目标、活动主体与教学流程上的教学设计,详细阐述了以学生为中心的教学实施,并全面评价了教学实践。  相似文献   

2.
基于师范类专业认证理念与毕业要求的教学前端分析,建构“学教评产”混合式教学模式,通过整合教学内容、重构教学安排与优化教学评价,对“化学游戏教学”课程进行创新性改革,并从学生学习成果、教学目标达成与学生满意度等3个方面评价教学成效。结果表明:该教学模式有助于学生学习成果质量的提升,能够有效促进教学目标的达成,并取得较高的学生满意度。  相似文献   

3.
张淑贤  商晓绪 《化学教育》2021,42(13):28-33
以“设计净水系统”为项目主题,介绍了项目教学主题选取、项目目标确定、项目规划、实施与评价策略。项目教学中,关注学生认知与思维发展,随着净水系统的设计、制作、测试和再设计项目学习活动的展开,引导学生综合运用化学、物理、数学等多学科知识方法分析解决问题,促进学生提炼真实情境下“物质分离与提纯”解决思路,发展化学学科核心素养,同时体验和感受完整的工程设计过程。  相似文献   

4.
孟献华  倪娟 《化学教育》2018,39(23):31-36
化学发展的历史能够作为重要的教学设计资源。将历史上的化学家开展科学研究和解决科学问题的过程,设计为可供课堂教学应用的学生问题,需要经过历史事件考察、学生水平分析、问题转化等步骤。以质量守恒定律为例,探讨了基于“历史复演法”的化学教学设计框架与实施。  相似文献   

5.
模型认知是重要的思维方法。基于模型认知进行教学设计,能促使教师从关注知识转向关注核心素养,从而使教学活动有效地促进学生思维能力的发展。在对模型及模型认知理解的基础上,以典型的符号模型“化学方程式”为例,阐明了教学思路和教学活动与学科观念的关系,形成了发展学生模型认知核心素养的教学设计。  相似文献   

6.
吴海萍 《化学教育》2018,39(19):23-27
以“基于桃酥烘培配方的实验探究”单元课的设计与实施为例,从情境素材的选取、课堂问题的设计、课堂任务的确定、学习活动的设计、持续性评价方案的设计等方面论述了促进“深度学习”教学的生成过程。  相似文献   

7.
以建构有机合成中的顺推法和逆合成分析法思维模型为载体,通过设置驱动任务,将信息技术和“教学评”一体化深度融合,促进学生结构观、发展观和转化观的形成,理解有机化学的社会价值,培养学生的宏微结合、变化观念、科学态度和社会责任等化学学科核心素养。  相似文献   

8.
为了解化学课堂探究教学“制订计划”的有效性,在课堂观察与分析的基础上,提出化学课堂探究教学“制订计划”系统分析量表,并结合具体化学课堂探究教学,从计划制订的主体、计划制订的过程、计划内容本身等3个方面解析了“制订计划”环节。结果启示:化学课堂探究教学“制订计划”系统分析量表能科学有效地指导化学课堂探究教学,特别是其“制订计划”的设计、实施与评价。  相似文献   

9.
邹国华  童文昭 《化学教育》2018,39(17):22-25
为提高各阶段教学的针对性和有效性,分析了离子反应知识的学习进阶,并探讨了教学序列的跨学段设计,为教师进行离子反应知识的教学实践提供参考。  相似文献   

10.
周正祥  杨玉琴 《化学教育》2018,39(23):25-30
以“原子结构模型的演变”为例,以化学史实为情境,设计环环相扣的问题,引导学生在分析证据及建构并评价模型的过程中体会实验证据与模型建构及演变之间的关系,认识模型在物质结构理论建立过程中的重要作用及其发展性特征。该教学设计在学生对原子模型的理解上具有显著效果。  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.
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.  相似文献   

13.
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   

14.
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   

15.
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   

16.
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.  相似文献   

17.
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   

18.
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.  相似文献   

19.
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   

20.
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   

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