《普通化学》中的实验数据表示方法

化学学科是建立在实验基础上的。许多重要理论、经验公式等都是对大量实验数据分析、归纳、整理之后抽象出来的。因此,在普通化学教学中重视对实验数据的引用,这不仅能培养学生分析问题和解决问题的能力,而且有助于学生对学科领域的基本理论和概念的理解。     

中学化学实验教学中的思维训练

中学化学教学大纲强调指出：“化学是-门以实验为基础的学科。实验教学可以帮助学生形成化学概念,理解和巩固化学知识,培养学生能观察现象、分析间题、解决问题,初步掌握-些常用的化学实验技能,培养学生实事求是、严肃认真的科学态度和科学方法。     

对中学生化学概念学习的调查研究

为了了解中学生化学概念的学习状况,采用编制问卷对苏州和无锡8所中学的初三、高一和高二的一千多名学生进行了调查。结果表明,学生对化学概念有很强的学习动机;大部分学生能辨析概念和掌握概念的内涵、外延;主要通过举例和自己琢磨习得化学概念,预习和类比方法运用不够,期望借助实验、多媒体学习化学概念;保持化学概念的方法中常用的是划线、分类和比较,画图表、复述和复习运用得不够。化学概念学习中存在着过度练习和轻视概念形成过程的情况。对此,提出了改进化学概念学习的建议。     

利用手持技术数字化实验测定中和反应化学计量比*

化学计量比在中学教学及实际生产中有着重要应用,本研究针对化学计量比概念教学存在的不足,以手持技术TQVC概念认知模型为理论依据,设计实验测定中和反应的化学计量比。基于等摩尔连续变化法,本实验借助温度传感器测定不同物质的量之比反应物反应后的温度变化数据,找出最大温度变化差值对应的反应物物质的量之比,即化学计量比,帮助学生从定量的角度理解化学计量比概念。     

化学数字化实验影响学生概念改变的实证研究

选取"离子反应"知识作为研究内容,开展了相关化学数字化实验的教学实践,通过二段式测验工具、SOLO分类法的量化分析,来检测化学数字化实验对学生概念改变的影响。结果显示,化学数字化实验能够在一定程度上促进学生的概念改变。     

运用计算机理论模拟辅助化学教学研究

以取代反应动力学研究、理解防晒品功效和红外光谱与分子构型等教学方案为例,探讨了计算机模拟中不同模块在辅助化学教学方面的应用,这些模块不仅能用于解释化学教学中学生较难理解的生涩概念,而且可以给学生提供亲身实践经历,更好地帮助他们总结数据以及形成自己的结论,激发学生对化学学习的兴趣,提高教学质量。     

研究教学法 提高中学化学演示实验的教学质量

全日制十年制学校中学化学教学大纲（试行草案）明确指出：“实验教学可以帮助学生形成化学概念,理解和巩固化学知识,培养学生观察现象、分析问题、解决问题的能力,获得比较熟练的实验技能,培养学生实事求是、严肃认真的科学态度。”同时也能培养学生的辩证唯物主义观点,激发学生学好化学的自觉性和积极性。     

初中生化学前概念中的相异构想及其形成方式

化学前科学概念(化学前概念)指学生专门学习化学前所形成的有关化学的认识,"相异构想"则是指学生形成的偏离科学概念的观点与认识.笔者以《全日制义务教育化学课程标准(实验稿)》涉及到的化学知识为载体,通过个人访谈、教师座谈会、试卷分析和调查问卷的形式,了解了初中生已具有的化学前概念以及存在的相异构想,并通过分析研究,总结出学生形成相异构想的主要方式:简单枚举、错误推理、主观臆测、望文生义、缺少辨证思想、缺乏化学思维能力等.     

在线化学实验安全考试系统的设计与应用

设计了一款在线化学实验安全考试系统,系统包括在线考试、数据分析等模块。利用此系统可以完成化学实验安全培训和考核。利用数据学习算法对学生考试结果进行了数据分析,评价了学生对安全知识的掌握情况,保证了实验课程的安全进行,能为实验教学提供有效帮助。     

素材的选择和运用对化学核心概念建构的影响——“盐类的水解”同课异构的实证研究

以"盐类的水解"同课异构实证研究为例,阐述了不同的素材选择和运用对学生核心概念建构不同阶段的实际影响,对在同课异构活动中教学素材库的确立、变量设计和控制等基本研究过程进行了论述。通过对没有显著差异的教师和学生进行同课异构活动,对同一个概念的建构选择不同的实验素材,课后对学生进行抽样访谈测评,获得不同的素材选择和运用对化学核心概念建构不同阶段的具体影响:"生活型""工业型"素材最能引起认知驱力;"生活型""探究型""单一型"实验更有利于概念的形成与建立;"对照型""单一型"实验更有利于概念的理解与变式;"生活型""工业型""复杂型"实验更有利于概念的迁移与应用及评价。     

Analytical chemistry of nonlinear systems

Analytical methods for characterizing complex, nonlinear chemical systems are reviewed. Emphasis is on those aspects of systems which make their characterization more difficult than just measuring concentrations or simple reaction rates. Examples include phase transitions, oscillating chemical reactions, laser fluctuations, and electrochemical oscillations. Data reduction algorithms specific to such systems are described.     

The current state of analytical control in Lithuania

In Lithuania research and development in chemical analysis are concentrated in scientific institutes and universities. The main fields of interest focus on biosensors, electrochemical sensors, sampling techniques and methods, study of atomization processes in spectrochemical analysis and noise evaluation in analytical measurements. Some laboratories also take part in international environmental monitoring programmes. There are about 50 researchers at the Ph.D. level engaged in analytical chemistry and several hundred technicians specialized in the field of analytical control. About one hundred chemical laboratories are active in scientific institutes, universities and factories. Specialized laboratories of chemical analysis are at the disposal of Environmental Control and Health Protection Departments and forensic investigation organizations. So far no laboratories are accredited according to the ISO 9000 norms. Special courses on analytical chemistry are offered at a few schools of higher education in the country. Only at the Department of Analytical Chemistry of the University of Vilnius specialized programmes are available to postgraduate students working towards a Ph.D. to improve their skills in current techniques of analytical chemistry. Recently the Technical Committee TC-16 for Chemical Analysis was formed within the standardization system of Lithuania. Its main activities are centered on issues such as national terminology, certified reference materials (CRMs), analytical methods and analytical quality assurance. There are numerous problems related to national terminology, the preparation of special documents in the field of analytical control and the production of regional environmental CRMs. Problems, also arise in obtaining and using CRMs for analytical instrument calibration and validation.     

美国AP课程中化学概念的引导式探究教学*——以“化学方程式”为例

在美国《AP化学课堂中的引导式探究活动》中,明确了概念性知识采用探究式教学方式的必要性,并根据学习圈理论依次划分出概念探究、概念形成、概念应用及概念评估4个连续的教学活动阶段,使学生能够全程参与到科学概念的形成过程中。以“化学方程式”教学内容为例,介绍了相关教学理论及在此基础上形成的探究式教学闭环,以期对国内中学有关化学概念的探究式教学改革起到一定的借鉴与参考作用。     

Design of thiol-containing amino acids for native chemical ligation at non-Cys sites

<正>Protein chemical synthesis usually relies on the use of native chemical ligation that couples peptide thioester with a Cys-peptide.A limitation of this method is the difficulty of finding an appropriate Cys ligation site in many synthetic targets.To overcome this problem,the ligation-desulfurization approach has been developed.This approach involves the use of a thiol-containing amino acid as the ligation partner.After the sequence assembly is completed,the thiol group is removed through a desulfurization reaction to generate the standard amino acids.Currently this strategy has been applied to the ligations at a number of amino acids including Ala,Phe,Val,Lys,Thr,Leu,Pro and Gln.The present article reviews the design and synthesis of these thiol-containing amino acids for native chemical ligation at non-Cys sites.     

Evaluation of the Chemical Exergy of Fuels and Petroleum Fractions

A correlation formula to estimate chemical exergies of oil fractions and fuel mixtures from enthalpy of combustion and atomic composition is developed. Heat capacity ofa mixture of 10 hydrocarbons was measured in the range 5–290 K. It was shown that contribution of entropy of mixing to exergy of typical oil fractions is about –0.11% in the approximation of ideal solution, and about –0.18% for a real solution. This revised version was published online in July 2006 with corrections to the Cover Date.     

Kinetic study of depolymerization of polyurethanes: A experimental and computational insight for chemical recycling

This work reports experimental and computational studies of polyurethanes depolymerization from industrial waste through a reaction with potassium hydroxide. A computational study was performed to identify the chemical reaction mechanism, which is more difficult to determine experimentally. Kinetic and thermodynamic parameters of activation process were also obtained by theoretical calculations. An experimental procedure led to products identified by ¹³C solid-state NMR analysis, which agree to the computational study. A small variation of less than 5% in the activation energy values found between the data obtained through theoretical calculations and experimental methods suggests that the described computational procedure is enough to describe the process in a satisfactory manner.     

高中学生化学概念掌握和问题表征程度关系的实证研究

本研究结合国内外有关化学概念教学的研究情况,对高中学生化学概念掌握和问题表征程度的关系进行了实证性的探索和研究。设计并在江苏省7所不同类型的学校进行了有关化学概念掌握的研究测试,同时选取优差学生进行有关化学问题的口语报告作业。研究结果表明：学生化学概念理解水平显著地影响着其解题时的表征程度。     

化学计量在产品质量保证中的重要作用

阐述在化学分析中,由于增强了化学计量意识,满意地解决了粘胶基碳布质量问题,显示出化学计量在产品质量保证中的重要作用。     

基于核心素养的化学实验社团活动*

通过问卷的形式调查了赣州市高中化学实验教学开展的情况,结合赣州中学化学实验社团开发与运行的实际,研究了化学实验社团的创建与运行、开展趣味化学实验社团活动、社员参加化学研学活动、拍摄社团原创趣味实验视频、创办化学实验社团公众号、创新改进教材实验等等。实践结果表明:在高中开发化学实验社团具有可行性和操作性,通过开展化学实验社团活动,可以锻炼学生多方面的能力、促进学生化学核心素养的发展。