高中生“化学守恒”思维水平状况的调查分析

“化学守恒”是化学学科的基本思想之一,学生若在学习过程中具备守恒思想,将能提纲挈领地把握化学规律,更深刻地理解化学本质.结合学生的认知水平对“化学守恒”内涵进行界定,并制定了“高中生‘化学守恒’思维水平考查指标体系”,运用测试和访谈等手段来考查高中生“化学守恒”思维水平状况.结果表明:高中生对“化学守恒”思想的理解处于中等水平,且对“物质守恒”的掌握明显优于对“能量守恒”的掌握.     

化学课堂教学板块及其设计与分析——祝贺《化学教育》刊庆30周年

在课堂观察和分析的基础上,基于整体观,提出了化学课堂教学板块理论,认为“情景”、“任务”、“活动”和“评价”是“板块”的基本构成要素,并对基于“板块”的化学课堂教学设计进行了分析和探讨。     

努力学习、研究、实践"全面的化学教育"理论--纪念戴安邦先生逝世5周年

“全面的化学教育”理论凝聚着中国化学教育工作者的集体智慧和心血,是具有中国特色、学科特点和时代特征的学科教育理论。本文介绍了戴安邦先生对“全面的化学教育”理论的贡献,并通过辑录我国化学教育工作者的有关论述介绍了这个理论的主要内容。作者认为,努力学习、研究和实践“全面的化学教育”理论,是提高化学教育质量、发展化学教育的需要。“全面的化学教育”理论还有待于进一步完善,还有许多工作要做,当前特别要注意以社会需要和化学教育功能为基础,树立新时代的化学教育使命观;以学生的发展为本,树立新的“基础”观;以学生为主体,树立新的教学观。     

探索"任务驱动"下的化学教学设计与实施

本文介绍了什么是“任务驱动”化学教学模式,阐述了这种教学模式对于推进化学课程和教学改革的意义,对如何设计化学学习任务和化学学习支持系统,以及如何实施“任务驱动”教学,促进学生发展做了比较具体的讨论。     

设计系列化学实验优化化学实验教学的研究和实践

在化学实验教学中,结合现代教育理论,探讨了“阶梯式”、“精深式”、“激趣式”和“创新式”系列化学实验的设计,以支持和促进学生的学习,努力构建一种从实验中连贯建构知识意义的教学过程,提高化学实验教学的有效性。     

导演“故事”须严谨聆听“故事”须用心——对化学实验的一点认识和思考

做化学实验是从事化学相关领域研究及开发工作的人所采用的最主要研究手段。将“化学实验”与“故事”进行类比：化学工作者做一个化学实验就好比是他导演了一个“故事”,而做此实验的整个过程也如同是他在聆听这一个“故事”。化学工作者进行化学实验的目的,就是要把“故事”听懂。就怎么样才能够更好地把“故事”听懂以保证化学实验成效的问题,以合成制备实验为例从几个方面进行了阐述。     

谈化学概念教学中的主要策略

化学概念是化学现象和化学事实本质属性的反映,在化学教学中具有重要地位。为了使化学基本概念教学达到教学大纲规定“使学生准确地理解基本概念”,笔者在化学概念教学中“讲什么”和“怎样讲”两个间题进行了多年探索,以下谈一些认识和教学策略。     

化学类专业课程思政要素与途径的探索和实践

探讨了化学类专业课程思政要素、教学方法和途径,提出了“六维度、四构建”思政教学策略。从化学中的哲学思想、化学的价值观、化学科学精神、化学思维方法、化学伦理、化学文化“六维度”确定化学类专业课程思政要素;以教学目标创建为基础、教学内容和教学资源重构为重点、教学方法构建为关键、成绩评定体系建立为保障的“四构建”系统设计课程思政的教学方法和途径。基于“六维度、四构建”课程思政策略,对无机及分析化学课程进行了教学实践。实施结果表明,这些策略能有效提高课程育人的针对性和有效性,为高校同类课程思政建设提供一个可借鉴的思路和模式。     

试谈分析化学的明天

分析化学是化学学科几大主要二级学科之一 ,曾被认为是“现代化学之母”[1] ,“化学是从分析化学开始的”[2 ] 。但是近年来情况却发生了变化 ,从有人说“不管人们喜欢不喜欢 ,化学正在走出分析化学”[3] ,到 1 981年英国曼彻斯特大学理工学院建立独立的“仪器装置和分析科学系” ,及国内外一些单位相继建立分析科学实验室或研究所 ,出版《分析科学学报》 ,到最近高鸿先生明确宣布“分析化学的现状和发展趋势都在说明分析化学实际上不再是化学的一个分支”[2 ] 。“分析化学已发展到分析科学阶段”在分析化学界几乎已成了共识。　　“化学之…     

化学综合设计实验教学模式的改革

简要介绍了北京师范大学化学学院“化学综合设计实验”的教学模式,从7个方面重点介绍了按照科学研究的一般过程组织“化学综合设计实验”的一些尝试以及点滴经验和体会。     

烟花爆竹漫谈

对烟花爆竹的简史、现状进行了简要的介绍。探讨了燃放烟花爆竹可能产生的化学污染,展望了烟花爆竹未来发展。     

化学与申奥

本文探讨了化学在申奥中的意义,分别介绍了绿色奥运、科技奥运、人文奥运中的化学问题。     

High‐Nitrogen‐Based Pyrotechnics: Development of Perchlorate‐Free Green‐Light Illuminants for Military and Civilian Applications

The development of perchlorate‐free hand‐held signal illuminants for the US Army’s M195 green star parachute is described. Compared with the perchlorate‐containing control, the optimized perchlorate‐free illuminants were less sensitive toward various ignition stimuli while offering comparable burn times and visible‐light outputs. The results were also important from the perspective of civilian fireworks because the development of perchlorate‐free illuminants remains an important objective of the commercial fireworks industry.     

Green Chemistry and Modern Technology

The basic principles, approaches, and early achievements of green chemistry are considered. The definition of green chemistry as a branch of chemistry that studies the laws of passing of chemical reactions and the properties of substances participating in such reactions, with the aim of acquiring basic knowledge that provides a basis for designing chemical technologies that eliminate (sharply curtail) the use and production of materials that pose a risk to the environment.     

"Green" pyrotechnics: a chemists' challenge

Fireworks are probably the application of chemistry which resonates best with the general public. However, fireworks and (civil and military) pyrotechnic applications cause environmental pollution and thus have given rise to the development of new, environmentally friendly pyrotechnic compounds and formulations. Nitrogen-rich energetic materials, such as the derivatives of tetrazoles and tetrazines, are about to revolutionize traditional pyrotechnic compositions. This Review summarizes the sources of pollution in current formulations and recent efforts toward "green" pyrotechnics.     

High‐Nitrogen‐Based Pyrotechnics: Perchlorate‐Free Red‐ and Green‐Light Illuminants Based on 5‐Aminotetrazole

Prototype testing of perchlorate‐free hand‐held signal illuminants for the US Army’s M126 A1 red‐star and M195 green‐star parachute illuminants are described. Although previous perchlorate‐free variants for these items have been developed based on high‐nitrogen compounds that are not readily available, the new formulations consist of anhydrous 5‐aminotetrazole as the suitable perchlorate replacement. Compared to the perchlorate‐containing control, the disclosed illuminants exhibited excellent stabilities toward various ignition stimuli and had excellent pyrotechnic performance. The illuminants are important from both military and civil fireworks perspectives, as the perchlorate‐free nature of the illuminants adequately address environmental concerns associated with perchlorate‐containing red‐ and green‐light‐emitting illuminants.     

Periodate salts as pyrotechnic oxidizers: development of barium- and perchlorate-free incendiary formulations

In a flash: pyrotechnic incendiary formulations with good stabilities toward various ignition stimuli have been developed without the need for barium or perchlorate oxidizers. KIO(4) and NaIO(4) were introduced as pyrotechnic oxidizers and exhibited excellent pyrotechnic performance. The periodate salts may garner widespread use in military and civilian fireworks because of their low hygroscopicities and high chemical reactivities.     

ICP-AES法测定烟花爆竹中16种化学成分的不确定度评定

采用电感耦合等离子体-原子发射光谱(ICP-AES)法测定烟花爆竹中16种化学成分并对测定结果的不确定度进行了评定和计算,提供了评定过程所需的各参数的采集和计算方法,定量表征了测定结果的可信程度.由计算得到的合成标准不确定度可以看出,不确定度主要来源于校准曲线的非线性,从而对此测定方法的可行性和准确性进行了科学的判断.     

Modeling and calculation of thermal explosion time to ignition of cylindrical fireworks and crackers

To analyze the thermal safety of cylindrical fireworks and crackers in storage and transportation, this article establishes a physical model and a mathematical model of thermal explosion time to ignition of finite cylindrical fireworks and crackers. And in order to simplify the thermal explosion model, effective Biot number about boundary condition is deduced according to the theory of heat transfer. The partial differential equation of thermal explosion model are calculated with difference method in Matlab program, to obtain the time to ignition as well as the temperature–time history before explosion system explodes. The rationality of effective Biot number and calculation method is proved through comparison of calculation solution and literature solution. Being the first to solve the problem of two-dimensional thermal explosion unsteady-state model of fireworks and crackers, where the upper surface, lower surface, and side surface have different heat dissipation conditions. Meanwhile, calculation steps were shown about a type of fireworks.     

Thermal explosion model and calculation of sphere fireworks and crackers

In order to analyze thermal safety of fireworks and crackers, thermal explosion models of three kinds of sphere fireworks and crackers with different structures are achieved on the basis of thermal explosion theory, and thermal resistance of shell and effective Biot number are deduced as for boundary conditions. Two models are calculated with target-shooting method in Matlab program, and the rationality is proved through comparison of numerical solution and classical solution. Meanwhile, calculation steps are shown about a type of firework. The study has a great significance to thermal safety analysis of fireworks and crackers.