化学教学中问题情境创设的策略研究

新课程理念下的化学课堂教学要求教师在教学过程中不断探讨新的教学方法和实施新的教学手段.课堂教学中恰当创设问题情境,有利于教师在教学中提高课堂的效率,激发学生学习化学的兴趣,培养学生的创造性思维能力,体现新课改精神.     

提高课堂教学开放性和实效性的研究

新课程的背景下,我们化学组针对课堂教学进行了研究,特别是教学的实效性和开放性的2个角度进行了有计划和有目的的研究工作。本研究从课堂教学实效性——还给学生的学习主动权、课堂教学实效性——改变学生的学习方式、课堂教学实效性——改变学生的学习方式、课堂教学实效性——提高教师自身的能力、课堂教学实效性——学生、教师共同提高促进、化学教学的开放性——我们的教学方式和采取的措施、化学教学的开放性——思维培养能力发挥等进行论证分析,取得了好的成果。     

谈新课程理念下化学课堂教学中的预设与生成

随着课程改革的不断深入,课堂教学更加注重学生的主体地位,强调师生的互动和合作。而在这互动的过程中意味着更多的不确定性和生成性,因此生成性是新课程课堂教学的重要特征,也是新课程教学区别于传统教学的重要方面。同时,我们的课堂教学又是有计划有目的的活动,这意味着课堂教学必须具有一定的预设性,于是预设与生成就构成了新课程教学中的一对基本矛盾,共同存在于课堂教学之中。预设中有生成,生成离不开预设,只有预设的课堂也许是有秩序的课堂,但会缺乏些许灵气;生成的课堂也许会显得散乱一些,但可能会因此而精彩。在实际的课堂教学过程…     

谈化学教学过程中生成性教学资源及利用

课堂生成性教学资源是教学活动前不能预设的、在教学过程中动态生成的有利于教学目标实现的各种因素。化学生成性教学资源产生于动态的化学教学过程;学生是化学教学资源的重要构成者和动态生成者;教师是化学生成性教学资源的开发者和课堂教学资源的重组者。化学教学过程中教师应对生成性教学资源加以识别、开发和利用。     

新课程背景下化学课堂有效教学反思的4个问题

新课程教学中,有效的课堂教学是每位教师的追求。在对课堂教学自我反思时,教师可以通过对自己提出这节课让学生获得了什么?是否每位学生都有所收获?让学生怎样获得知识的?让学生用多长时间获得?通过反思这4个问题,可以衡量和评价课堂教学的有效性。     

浅谈现行初中化学教学中的探究课

随着基础教育课程改革的推进,福建省三明市梅列区初一学生用上了新一轮课程改革后的新教材。初中化学由于学科特点,2004年秋季才能用上按课程标准编制的教材,而新的形势要求初中化学教师在现行初中化学教学中必须渗透新课程理念。在现行教材中渗透新课程理念,既是教师自身完善的需要,更是学生发展的需要。既然如此,我们初中化学教师不得不思考：现行初中化学教材在教学中,如何渗透新课程倡导的以科学探究为主的多样化的学习方式?探讨这一问题对初中化学教师在2004年面对现在初一学生,能够在新课程理念下,为了每位学生的发展,自如地进行初中化学课堂教学,具有深广的现实意义和价值。     

从课程标准到教材到教学——以高中化学新课程必修模块氧化还原反应内容为例

高中课程改革是个系统改革,从课程理念到课程目标、课程内容、教材、教学和评价都发生了一系列变化.课程标准是指导性文件,教材是教师教学的核心素材和资源.教师在实施高中新课程的过程中,怎样看课程标准?怎样分析高中新课程的教材?怎样具体到课堂教学的设计?即怎样从课程标准到教材到教学?这将是什么样的工作思路和流程.以高中化学新课程必修模块氧化还原反应内容为例进行了探讨,给教师提供了一种实施高中新课程教师教学设计工作的基本思路.     

教材中隐含课程资源的适度开发和利用

化学必修和选修教材中设置有丰富的隐含课程资源,教学过程中可结合学生实际适度开发和利用,以满足学有余力学生的需求,充分发展学生智力,培养学生能力。同时也是教师对新课程的发展和完善,使课程改革与教学实际有机结合,从而促进教师的专业发展。     

移动学习APP在仪器分析实验教学中的应用*

仪器分析课程是大学中培养创新人才的重要实验课程。为解决学生在实验学习过程中基础薄弱、操作能力较弱,以及课堂教学效率和效果不佳等问题,研究设计和开发了微信小程序APP,辅助学生进行实验学习。APP的主要功能包括学习资源呈现、仪器操作指南、实验交互式探究。通过观察、访谈、问卷的方法对APP的应用效果进行研究,研究结果表明,移动学习APP的学习资源、实验操作、实验探究的功能能够有效帮助非化学专业的学生进行实验学习,减轻了教师教学的压力,学生在使用APP过程中的认识负荷也较低。     

“课堂动态生成资源”的引导及其优质化

"课堂动态生成资源"包括"预期资源"和"昙花资源"。从教学创作的3个过程探讨了"课堂动态生成资源"的产生过程。以"原电池"的教学案例,从3个课堂教学层次探讨教师如何去主动引导"课堂动态生成资源",并使之常态化和优质化。教师只有深入了解"课堂动态生成资源"的重要性,才能从关注层次上升到主动引导生成,从而使"课堂动态生成资源"常态化,"预期资源"和"昙花资源"才能优质化。     

利用手持技术改进测定乙醇分子结构实验

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。     

光谱仪测试范围的扩展

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。     

Dichroism of absorption and polarization of phosphorescence of molecules of the closed form of nitrobenzospirothiopyran

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.     

Influence of viscosity of medium on processes of oxygen quenching of excited states of mesoporphyrin

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.     

Determination of heats of detonation and influence of components of composite explosives on heats of detonation of high explosives

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

     

物质分配系数的测定实验改进

实验教学目的是从解决实际问题出发,以实验技术训练和实验设计思想培养为目标。介绍了将单一的物质分配系数测定实验改进为综合实验,提高了实验效果及实验资源利用率。     

Neutral diterpenoids of oleoresins of five species of conifers of Transcarpathia

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.     

Calculation of enthalpies of hydrogenation of hydrocarbons

Sets of hydrogen molecule equivalents have been developed which permit the calculation of hydrogenation of different types of carbon-carbon bonds from ab initio total energies (3-21G and 6-31G* basis sets, and, to a more limited extent, for MP2/6-31G* data) of reactants and products. The calculated enthalpies of hydrogenation are in good agreement with experiment for unstrained molecules, with average errors on the order of 2 kcal/mol. The 6-31G* equivalents allow the enthalpies for strained molecules to be calculated accurately, but the 3-21G equivalents do not. The equivalents for both basis sets have been tested by calculating the enthalpies of hydrogenation of carbon-carbon bonds in nitrogen- and oxygen-containing organic molecules, free radicals, and classical carbocations. The results are in good agreement with experiment in most cases.