试论化学表达能力的培养

广大化学教师在教学中已普遍重视中学生观察能力、实验能力、思维能力和自学能力的培养。这是学生解决简单化学问题和提高化学素质的基本要求。     

"自主创新"教学模式在化学奥赛培训中的实践与研究

本文简述了“自主创新”教学模式的形式及涵义，并把近年来在化学奥赛培训中对“自主创新”教学模式的实践体会作了归纳与总结。其中概述了“自主创新”教学模式在培养学生自学能力、实验能力及创新能力的方法与措施作了较深入的分析。     

初中化学实验教学中对学生观察能力的培养

九年制义务教育化学教学大纲明确指出：“在教学中,教师要处理好知识、技能和能力的关系。培养和发展他们的观察能力、实验能力。思维能力和自学能力等。”下面是我在实验教学中对学生进行观察能力培养的一点作法和体会一、明确实验目的激发学生的观寨兴起初中化学是化学教育的启蒙阶段。化学基本概念、基本理论的建立、元素化合物知识的提出、化学计算的出现,无不是源于化学实验。因此,组织好实验教学是化学教学非常重要的一环。在演示实验中,教师除按基本操作要求进行示范操作外,引导学生有目的地观察实验现象是实验教学的关键所在。…     

化学教学中培养学生能力的探索

现代科学技术飞速发展,有人估计知识量每八年到十年翻一番。面对这一形势,我们的教学必须狠抓能力的培养,为学生打好创造性发展的坚实基础。培养学生哪些能力呢?根据化学学科的特点。我认为主要是培养学生的观察能力、思维能力、实验能力和自学能力。这几种能力是相互联系,不可分割的。     

师专化学文献课内容简介

为了提高高等学校学生的自学能力和独立工作能力,根据(84)高教字(04)号文件精神,1985年初,我校化学专业有机教研组经过多次讨论,决定开设“文献检索课”和“文献实验”,并自编了“化学文献检索简介”教材。起初两年,文献课以讲座的形式开出,后来均固定学时开课,并且开放资料室、图书馆期刊阅览室、工具书库、过刊库,给文检实践提供方便。1985年以来,从未间断过。     

中学化学自学能力培养初探

自学能力是有多种心理机能参与的一种综合性能力,它本身属于一般的学习能力范畴,但在各个学科领域又有它特殊的体现。在化学教学中如何培养学生的自学能力和自学习惯,我们通过一年多的化学自学精讲教学试验,作了一些初步探讨。一、中学生自学过程中的心理因素中学化学教学面对的是15-18岁的青少年,他(她)们经过连贯、系统的小学和二年的初中教育后,都自觉或不自觉地具备了一定的阅读能力、观察能力、思维能力等各种能力。进入普通中学的学生一般都是学习成绩中等或较差的,这些学生成绩不好,往往不是因为智力方面的原因而是缺乏毅力和勤奋精神,缺乏自学能力和自学习惯。     

BODIPY基荧光探针的合成、表征及对铜离子的检测——推荐一个大学综合化学实验

介绍了一个大学综合化学实验——BODIPY基荧光探针的合成、表征及对铜离子的检测。该实验是一个科研转化的大学生综合化学实验,内容包括3,5-二氯BODIY的合成、BODIPY基荧光探针分子的合成,以及利用紫外-可见分光光度计和荧光光谱仪检测目标分子对金属离子的响应性。通过本实验,使学生了解BODIPY基荧光传感器这一科研前沿领域,激发学生对科学研究的兴趣,培养学生的科研探究能力。本实验综合了有机化学、仪器分析和应用波谱学知识点的学习,培养学生的实验操作技能,提升学生的综合及创新能力,建议纳入高年级综合化学实验课程。     

终结性化学实验技能目标达成度的认定

学生掌握实验技能,远非一日之功,往往要通过较长的时间的反复操作、矫正、强化,才能准确掌握达成目标。为此,我校化学组自1989年始把学生实验技能的检测安排在实验课程的终端,并对学生技能操作的内容及方法进行不断的实践,探究了终结性化学实验技能目标达成度的认定,其内容及方法已被我省中专卫校化学校际研究会推广,决定1996年开始在全省各中专卫校化学实验中实施。     

多方位教学方法探索与实践——西安交通大学少年大学生化学原理课程教学研究

针对少年班学生年龄及知识结构特点,在化学原理课程的教学中,探讨了启发式教学、对比式教学、应用实例式教学、讨论式教学等多方位教学方法的研究与实践。目的是探索一种更好地培养少年班学生的学习方法、自学能力、运用知识的能力和科学思维与创新思维能力的教学方法。最后,介绍了实践应用效果。     

制约高中生化学学习积极性的因素及对策

高中生对化学及化学实验的认识不足,有些学校不重视实验课,该开的实验不开,不少化学教师的课不能令学生满意,学生缺乏适宜的化学学习方法。化学教师应改进教学方法,加强化学与社会生活及生产的联系,加强学法指导,充分发挥化学实验的功能,提高课堂教学的有效性。     

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.     

非那雄胺合成工艺改进

非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。