初高中衔接过程中化学实验教学"学案"的特点——以新课程人教版"萃取"为例

介绍了人教版《普通高中课程标准实验教科书.化学(必修1)》"萃取"的教学实例。以"萃取"一课的"学案"为例分析了初高中衔接过程中化学实验教学"学案"的特点。     

初高中化学衔接教学的调查研究

通过对高一学生化学学习情况的调查并结合初高中化学在教学方法、教学内容、评价体系等方面的差异性分析,探究初高中化学衔接教学策略。     

化学类本科综合化学实验教学的实践与思考

综合化学实验是联系基础化学实验和过渡到本科毕业论文专题研究的一个桥梁。本文根据笔者多年的设计型综合实验教学,概要阐述了综合化学实验教学中如何贯彻综合化学的基本特征,依照"教师引导,学生主体"的思想,帮助学生了解学科发展的前沿热点,锻炼查阅文献和阅读、提炼其实验精华、主动探究和学习的能力,以达到锻炼学生的实验操作能力和提高学生的整体素质。     

理论指导实践化学实验教学模式的建构及实践

教材中演示实验或探究实验是针对某一个实验原理引导学生学习化学知识与实验操作技能、验证化学原理、训练科学思维.理论指导实践的化学实验教学模式旨在引导学生用学习过的化学知识和化学实验技能对未知领域进行综合性探索,学习新知,培养创新能力.     

例谈“简异”化学实验创设的教学价值

阐述了通过“简异”化学实验的创设,增加化学实验的趣味性,激发学生的好奇心和求知欲;提升化学实验教学的探究性,培养学生的探究能力,实现化学知识的系统建构;引导学生理性质疑书本实验,实现化学实验的创新教育价值。     

以举办化学实验竞赛为契机,推动化学实验教学发展

第10届大学生化学实验竞赛在北京化工大学成功举行,大学生化学实验竞赛能检验学生掌握化学实验技能和操作水平的情况,促进学生更好地了解和掌握实验仪器,锻炼学生的动手能力和创新意识,培养学生严谨科学的态度。通过"北京市大学生化学实验竞赛"这个平台,高校之间更好地交流了化学实验教学的经验,并以此为契机促进化学实验教学的改革,提高化学实验教学水平。     

基于英才班学生创新能力培养的元素化学实验教学

根据英才班学生的特点,在元素化学实验教学过程中,引导学生从思想上认识到元素化学实验的重要性,强化实验预习环节,精讲实验内容,有意识地引导学生重视反应条件对元素化学实验现象和产物的影响,支持和鼓励学生做探索性实验,实验完成后适时总结,通过以上措施不仅激发了英才班学生对元素化学实验的兴趣,而且培养了英才班学生的创新能力和科学素养。     

“思想实验”的价值及在实验教学中的实践路径*

对“思想实验”的发展历程及其在科学和技术创新活动中的意义进行了综述。提出了将“思想实验”与化学实验教学结合的启发式教学策略,优化了现行的化学实验教学流程。采用引导学生对实验步骤的设计思路进行反向逻辑推理和分析的教学方法,能够提升学生的创新思维和创新实践能力。     

“基础化学”模块化、超市化递进式实验教学探索

针对目前"基础化学"理论和实验教学的现状,实行模块化、超市化实验项目建设,进行分层式、递进式开放实验教学探索。调查研究表明新的实验教学模式有利于弥补学生化学基础的不足,增强化学实验基本操作技能的训练,保障学生面向药学类各职业岗位所必须具备的操作技能,提高"基础化学"的教学效果,真正发挥"基础化学"对后续课程的支撑作用。     

基于视频辅助的“翻转课堂”技术在高分子化学实验课程中的应用

在《高分子化学实验》教学过程,采用"翻转课堂"的教学理念,广泛采用视频讲义辅助教学,有效提高学生主动学习的能力,增加教学的互动性,通过多元化的实验项目设计,培养学生的分析问题、解决问题的能力,深化理论教学的效果。由于"翻转课堂"教学方式的引入,提高了学生对实验项目的领悟能力,并辅助大量的引导问题,有效实现了实验教学和理论教学的统一。通过引入视频教学的特点,有效缓解了传统实验教学中,实验仪器不足,场地紧张的难题,充分提高实验设备的使用效率。综合设计《高分子化学实验》课程的实施方式和管理制度,为视频化讲义的推广积累有益的经验。     

化“材”为“筑”

Chemistry is a central, practical and creative discipline. The development of chemistry plays an important role in the progress of science and society, as well as the improvement of the quality of human life. This paper introduces the chemical knowledge of stone, concrete, glass and other inorganic nonmetallic building materials by the anthropomorphically story. Taking nanomaterials as an example, the prospect of building materials development in the future is put forward.     

"Alpha"-, "beta"- and "delta"-anhydrodigitoxigenin

The syntheses of 3β-hydroxy-5β-carda-14, 20:22-dienolide (= «β»-anhydro-), 3β-hydroxy-5β-carda-8:14, 20:22-dienolide (= «α»-anhydro-) and «δ»-anhydro-digitoxigenin (= probably 3β-hydroxy-5β, 14β-carda-8, 20:22-dienolide) by the best ways known to date, have been described. «δ»-Anhydro-digitoxigenin represents the thermodynamically most stable isomer. In this isomer the double bond in position 8 is unaffected by hydrogenation with Pt in acetic acid; with perbenzoic acid an epoxide results from which, on hydrogenation, the double bond can be regenerated in its original position. Analogous reactions are known to occur in the 8:14-epoxides.     

Making "wheels" and "cubes" from triangles

[Mn(IV)Mn(II)3] triangular units directed by the presence of tripodal alcohols self-assemble in the presence of azide and acetate ligands to form either a [Mn24] "wheel" or a [Mn32] "cube".     

"Turn-on" fluorescent sensing with "reactive" probes

Chemical probes are valuable tools for the investigation of biochemical processes, diagnosis of disease markers, detection of hazardous compounds, and other purposes. Therefore, the development of chemical probes continues to grow through various approaches with different disciplines and design strategies. Fluorescent probes have received much attention because they are sensitive and easy-to-operate, in general. To realize desired selectivity toward a given analyte, the recognition site of a fluorescent probe is designed in such a way to maximize the binding interactions, usually through weak molecular forces such as hydrogen bonding, toward the analyte over other competing ones. In addition to such a supramolecular approach, the development of fluorescent probes that sense analytes through chemical reactions has witnessed its usefulness for achieving high selectivity, in many cases, superior to that obtainable by the supramolecular approach. Creative incorporations of the reactive groups to latent fluorophores have provided novel chemical probes for various analytes. In this feature article, we overview the recent progress in the development of turn-on fluorescent probes that are operating through chemical reactions triggered by target analytes. Various chemical reactions have been implemented in the development of many reactive probes with very high selectivity and sensitivity toward target analytes. A major emphasis has been focused on the type of chemical reactions utilized, with the hope that further explorations can be made with new chemical reactions to develop reactive probes useful for various applications.     

"Decoking" of a "coked" zeolite catalyst in a glow discharge

'Decoking' of a 'coked' zeolite catalyst in a glow discharge in oxygen is investigated. The 'decoking' process involves reactions of atomic oxygen (O atoms) with 'coke' and yields gases such as CO, CO₂ as well as other gaseous products that could be easily pumped out.Three different modes of discharge were investigated including a static mode, a flowing-gas mode, and a periodic-purge mode where the oxygen and other gaseous products of the discharge were replaced by fresh O₂ gas after short but regular intervals of time. In some cases, additional heating was also used to provide base temperatures of the order of 100 °C to facilitate penetration of oxygen atoms into the inner layers and cages of the zeolite catalyst.This paper presents some results of spectroscopic analytical techniques used to monitor the atomization of oxygen, oxidation of 'coke', and to confirm the process of 'decoking'. More specifically, radiation emission on the 3 s ⁵S– 3p ⁵P transitions of O around 777.2–777.5 nm were selected for monitoring the atomization of O₂. On the other hand, X-ray photo-electron spectroscopy (XPS) was used to determine the amount of residual carbon and extent of 'decoking'. Furthermore, evolution of CO and CO₂ gases as a function of time was systematically monitored in real time. For CO, the 451.1 nm band head belonging to the B¹ - A¹ bands of the Angstrom system of the CO spectrum was used, while for CO₂, the band head at 353.4 nm belonging to the CO₂⁺ spectrum was used. The rates of evolution of CO and CO₂ were related to the rate of 'decoking' of the catalyst. It is noted that in the periodic-purge mode, about 63% of the total yield of CO from a given sample of the catalyst appears in the first 3-min exposure to discharge whereas it takes up to 15 min to remove nearly 94% of the removable carbon under our experimental conditions.     

营养化学课程翻转课堂的探索与实践

With its tailored learning content, flexible learning environment and directed teacher guidance, the flipped classroom in "nutrition chemistry" has effectively solved the problems of students' specialty, large number and limited time in the course of elective course. The teaching mode based on the cultivation of students' ability and the core of improving scientific literacy was constructed.     

Size evolution study of "molecular" and "atom-in-cluster" polarizabilities of medium-size gold clusters

A study on static polarizabilities for a family of gold clusters (Au(n), n = 6, 12, 20, 34, 54) is presented. For each cluster, a density functional theory perturbation theory calculation was performed to compute the cluster polarizability and the polarizability of each atom in the cluster using Bader's "quantum theory of atoms in molecules" formalism. The cluster polarizability tensor, α(cluster), is expressed as a sum of the atom-in-molecule tensors, α(cluster)=∑(Ω)α(Ω). A strong quadratic correlation (R(2) = 0.98) in the isotropic polarizability of atoms in the cluster and their distance to the cluster center of mass was observed. The cluster polarizabilities are in agreement with previous calculations.     

梦萦魂牵--《化学通报》复刊30年

哲学家和物理学家都喜欢研究和讨论“时间” ,时间之矢告诉人们光阴冉冉不复返 ,矢者失也。然而人们却总想回忆 ,寻找那些美好的或沮丧的过去 ,是安慰或自娱吧。我一直相信生活总是向前的 ,社会总是进步的 ,就和宇宙不停地膨胀一样。《化学通报》复刊已经 3 0年了 ,既然是复刊 ,必然先有停刊。历史总是把破坏和重建放在一起考虑的 ,才能找出规律。人们都说 2 0世纪是自然科学大发达的时代 ,然而 2 0世纪又是人类社会灾难最多的时代。正因如此 ,才促使科学多极化地、多样性地发展起来 ,从欧洲到美洲到亚洲 ,一点点 ,慢慢地扩散开来 ,也许 ,真…