共查询到20条相似文献,搜索用时 577 毫秒
1.
国外"化学概念教学"研究新进展 总被引:1,自引:1,他引:0
通过查阅《美国化学教育》(JCE)1995年7月至2003年7月有关化学概念教学的文章,对国外化学概念教学研究的新进展作一概述,列举了提出的关于化学概念教学的理论,并列举了“电子构型”和“分子模型”2个概念案例。另外,通过访谈国内先进教师和查阅国内相关教育期刊,对国内化学概念教学研究也作了一般概括。比较了国内外化学概念教学研究在主题的选择、研究的对象和方法上的差异以及给我们的启示。 相似文献
2.
国内"化学概念教学"研究新进展 总被引:4,自引:1,他引:4
以国内化学概念学习研究为主要内容,从3个方面分析了国内对化学概念学习的研究:(1)关于化学概念教学的经验性研究;(2)关于化学概念教学的理论性研究;(3)关于化学概念教学的现代研究。本文也简单分析了国外化学概念教学的研究,并且通过对比国内外化学概念教学的研究,得到了一些启示。 相似文献
3.
了解学生化学概念学习中存在的错误或模糊认识有利于提高概念教学的成效。选取了一些与环境化学相关的概念进行调查,从中找出学生存在的模糊认识,客观分析了学生环境化学迷思概念的成因,并提出了教学建议。 相似文献
4.
5.
6.
概念转变在近年来的科学教育中备受关注,教科书作为重要的教学资源对于学生转变概念进行化学学习能起到怎样的作用? 以Roth"科学教科书促进概念转变的原则"为框架,对上海地区通用的化学教材和美国高中主流理科教材"Chemistry:Concepts and Applications"进行对比,分析中美化学教科书在"促进学生... 相似文献
7.
8.
9.
"连接化学"是一种基于计算机环境的化学学习课程,它通过设置多个操作变量和窗口,向学生呈现微观粒子的运动、具体反应的变化曲线以及化学符号等,帮助学生建立宏观、微观和符号3者之间的联系,促进学生对化学概念的深刻理解.介绍了"连接化学"课程的界面、操作和特点,并分析了基于"连接化学"的概念学习框架. 相似文献
10.
中学化学概念教学之所见 总被引:1,自引:1,他引:0
化学概念是反映物质在化学运动中特有属性的一种思维形式。如果学生开始没有清楚地、准确地、深刻地理解化学基本概念,就不能对客观事物做出正确的判断和合乎逻辑的推理,最终不能获得正确的化学知识。可见,重视和加强化学基本概念的教学是提高化学教学质量的关键。本文运用逻辑学的知识和辩证唯物主义认识论的观点,阐述了化学概念教学的全过程,即:(1)初步形成概念;(2)同化理解概念;(3)把握充实概念;(4)强化巩固概念;(5)归纳总结概念(6)灵活运用概念。 相似文献
11.
利用手持技术改进测定乙醇分子结构实验 总被引:1,自引:0,他引:1
利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。 相似文献
12.
V. I. Bol'shakova L. I. Demenkova É. N. Shmidt V. A. Pentegova 《Chemistry of Natural Compounds》1989,24(6):691-694
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988. 相似文献
13.
14.
15.
由于石化行业的生产需要,其材质的使用具有多样性和广泛性,经常会出现顾客委托的测试样品的一个或几个元素跨越光谱仪现有测试程序测量范围的情况。本法通过对光谱仪测试原理的认识,根据光谱仪的测试能力及标样的采集,实现了一个或几个元素测量范围的扩展,并对其测量的影响因素进行了研究。 相似文献
16.
Influence of viscosity of medium on processes of oxygen quenching of excited states of mesoporphyrin
E. I. Kapinus V. A. Ganzha B. M. Dzhagarov E. I. Sagun V. B. Pavlenko 《Theoretical and Experimental Chemistry》1989,25(2):146-151
The oxygen quenching rate constants for singlet and triplet excited states of the dimethyl ester of mesoporphyrin IX increase with decreasing viscosity of the medium and reach a maximum at a viscosity of approximately 0.4 mPa·sec, after which the rate constants begin to decrease. The drop in rate constant with increasing fluidity of the medium may be related to a nonequilibrium character of the elementary act in the interaction of the reactants in the solvent cage. In viscous media such as isopropyl alcohol, isobutyl alcohol, and isoamyl alcohol, the reaction radius is greater than the sum of the radii of the reacting particles. The long-range character of these processes is due to the relatively weak dependence of the quenching probability on distance.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 161–167, March–April, 1989. 相似文献
17.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted
indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator
model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was
established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing
analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997. 相似文献
18.
19.
Effect of the Method of Modification of Zeolite X on Selectivity of Catalytic Methylation of Toluene
Voloshyna Yu. G. Pertko O. P. Patrylak L. K. 《Theoretical and Experimental Chemistry》2019,54(6):395-400
Theoretical and Experimental Chemistry - The effect of the method of modification of catalysts based on zeolite X by cesium and magnesium cations (ion exchange and impregnation) on the selectivity... 相似文献