谈化学教师备课中要妥善处理的六种关系

备课是教学工作中的一个重要环节,它直接关系到教学效果的良窳。我认为,化学教师在备课中要处理好以下六种关系。教学过程对学生来说,是由“未知”到“知”的过程;对教师来说,是一个将“已知”转化为“他知”的过程。可以说,教师的“已知”和学生的“未知”的矛盾构成了教学过程中的主要矛盾,而矛盾的主要方面则是教师的“已知”。     

我们是怎样进行初中化学的观摩教学

我校领导决定我组进行观摩教学,以达到交流经验和互相学习的目的,我们就根据当前课程进度选定了初中化学第八章碳的第四、五、六三节为观摩内容,并通知各个教员自己阅读课女,熟悉教材,打好集体备课的基础。一、集体备课观摩教学的前两夭先进行集体备课,作出了课时计划。备课是这样进行的:(召集同进度教学班的任课教员讨论研究。) 1.将教材再阅读一遍,深入体会,概括要点,再确定教学目的;大家一致认为这三节的重点     

课间二次备课——专家型教师的一种教学机智

通过观察法记录某专家型教师在不同班级的授课情况,从学生参与情况、教学内容的调整2个层面分析了课间二次备课的效果,认为课间二次备课是专家型教师特有的一种教学机智。     

化学学科理解视域下的教材单元整体备课*

基于学科理解进行单元整体备课,是教师把握学科知识体系、提升教学设计的站位、实现“素养为本”教学的重要基础。化学学科理解视域下的教材单元整体备课内容主要是对教材内容逻辑顺序与认识思路结构化的系统梳理,确定单元总体与课时教学目标,挖掘教材单元内容所内隐的学科核心素养与教育教学价值,对教学内容、策略进行重构与设计等。对课程标准进行解读理解和对不同教材版本相关内容进行比较整合是提升教材单元整体备课质量的有效途径。     

在化学实验工作中的几点体会

课堂实验是整个教学组成中的一个重要部分,它可以帮助理解和消化课堂上所讲的理论,使理论与实际联系起来,从而牢固地掌握科学知识,因此搞好课堂实验已成为任课教师的一个重要任务,现在将我在化学实验工作中的几点体会介绍出来供其他同志参考: 一、争取在老教师的指导下根据教学内容和进度选择实习材料,做好备课工作: 这一点对于刚担任教学工作的新助教来说是很     

问题式备课是实施问题探究教学的关键

问题探究教学是当前中学理科教学中普遍使用且效率较高的教学模式。该教学模式中,问题是教学的主线,教学活动自始至终围绕着问题展开,问题的设置至关重要,它直接关系到教学的效果和质量。从化学教师在备课过程中如何设置问题情境的角度介绍“三层面问题式备课”的基本程序及注意问题。     

创新完善集体备课制度，提升有机化学实验教学质量

集体备课作为有机化学实验教学中一个不可或缺的重要环节,数十年来,我们始终坚持并不断创新发展,使集体备课的内容更加全面、形式更多样化、实效性更强。集体备课促进了教师自身素质和教学能力提高,加快了一流实验教学团队建设,推动了实验教学内容、教学方法、教学手段以及实验室管理的创新发展,保障了有机化学实验教学质量稳步提升。     

从知识解析为本到基于学生认识发展 促进化学教学设计与实践向高水平跨越——北京师范大学化学教育研究所“高端备课”项目简介

“高端备课”意何在？“高端”一指基于专家支持和现代科学教育理论和方法（理念）指导;二指不断地超越和创新已有的教学设计水平;三指基于研究的教学设计与实践。“备课”一指将理念与教学行为的转化由备课（教学设计）这个桥梁来达成;二指科学教育研究必须源于教学设计与实践的真实问题和具体问题,这些问题的发现与解决都必须在真实的备课过程中,即要进行基于教学实践的研究;     

与青年化学教师谈备课

究竟应该怎样备课?对于经验较少的新教师来说,有的可能由于重视不够,以为备课很简单,只要熟悉教材就行了;有的由于信心不足,不知从哪里下手。作者拟以自己的体会与青年教师们进行讨论。     

青年教师在备课中应注意的某种偏向

青年教师有很多优点,如工作热情高,学习和接受新鲜经验快,有探索教学改革的强烈欲望等。但我们发现,有些青年教师在备课这个重要的教学环节上,程度不同地存在着一种偏向：不在刻苦钻研教材上下功夫,而是过早地翻阅教学参考资料。     

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。     

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.     

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.     

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。