科普实验教学项目:地沟油-膨润土去污皂的制备及去污率测定*

本科普实验设计以地沟油和膨润土为主要原料,通过皂化反应制备地沟油-膨润土去污皂,主要包括简化地沟油纯化流程、优化皂化反应配方、美化产品,实验的观赏性和互动性强。在此基础上,通过制作科普视频、宣传手册、举办体验活动等方式,全面立体地向公众展现地沟油纯化过程、皂化现象及其背后的化学原理等。     

“互联网+”背景下高职院校化学科普教育的实践

“互联网+”的理念使科普教育的形式更具多样化。讲述了高职院校开展化学科普教育的必要性;“互联网+”背景下化学科普教育的现状;以及基于互联网理念,通过制作科普动漫视频,开发科普小游戏,建立微信群等方式开展化学科普教育的实践,并总结了在实践中取得的成效。     

借光执笔的“蓝色精灵”——蓝晒中奇妙的光化学反应

生活中光化学反应无处不在。蓝晒印相是光化学反应的经典应用，因其经久不衰的蓝色深受人们喜爱。本实验立足于蓝晒的光化学反应特性，设计了不同方案分层次进行蓝晒照片制作、光化学反应原理、紫外线防护等科普实践。为了凸显化学与生活的联系，创新设计的“蓝晒与紫外线”实验可直观展示防晒的原理及效果。本实验操作简便、安全环保、观赏性强、兼具科学性与艺术性，易于理解、接受和参与，能够激发参与者对化学学科的兴趣，传播化学创造美好生活的理念。     

揭开指纹的神秘面纱

以化学指纹显影法为基础,设计了多种不同的科普实验,全面地向科普对象展示化学指纹显影的原理和特点。在科普模式上,项目创新性地将“线上+线下”模式相结合,“居家+实验室”环境相结合,打破了传统科普中受到时间、空间和仪器设备的局限,将科普的范围和广度大大扩大。另外在具体科普项目实施中,注重科普对象的科学和文化素养的提升,开拓公众视野并实现科学有效的辟谣。     

华东师范大学青少年化学科普基地的探索与实践

为激发青少年科学兴趣、培养青少年化学探究与创新能力和拓展高等院校的社会服务功能,华东师范大学建设了面向社会开放的青少年化学科普基地。科普基地以化学探索工作室、化学实践工作室和化学实验数字化工作室为主体,在空间布局上突出化学特色,具有科技展馆的视觉效果。科普基地开设了系列化学科普讲座、系列趣味化学实验及化学探究课题,构建了"中小学生、在校师范生和中小学教师"三位一体的教学实践模式,在青少年化学知识普及和实践创新能力培养方面取得了较好的实践效果。华东师范大学化学科普基地实现了青少年科普基地与学校常规教学工作的有机结合,有效地解决了高校自身培养目标与服务社会之间的矛盾,希望能为高等院校科普基地的建设提供有益的借鉴。     

油水界面的自发振荡：设计一个物理化学实验

近二十年来对化学振荡的研究已成为化学动力学的一个重要分支。据美国化学文摘所摘录,全世界每年约有二百篇左右的原始研究文献发表,从实验方法、反应机理、数学模型到化学振荡器性质与设计都进行了深入的研究。与此同时,有关化学振荡的实验也进入了物理化学专业实验讲义。一些杂志也从教学或科普的角度对化学振荡的原理和实验方法进行了较为     

三维化学结构动画制作教程

介绍了化学专业软件和多媒体工具整合使用制作avi和swf格式三维化学结构动画的实用技术,评价了多种简易多媒体工具的性能,并就专业软件和多媒体制作工具的整合使用作了简明扼要的阐述。该方法制作的swf格式的三维动画文件小、专业性强、效果真且兼容性好,适合各级各类学校化学教学、科普教育、科学研究及电子出版物结构动画的制作。     

色彩斑斓的自然,五颜六色的化学

通过介绍菠菜中色素的提取分离及紫甘蓝中花青素的提取两个实验,揭示大自然色彩背后的化学奥秘,并介绍了两个实验作为科普实验项目在化学科普活动中展示和互动的效果及特点。     

颜色背后的化学——一款以颜色为科普主题的实物展架的开发

北京大学化学国家级实验教学示范中心开发了一款以"颜色背后的化学"为主题的用于科普的实物展架。它以颜色相关化学理论为逻辑主线,通过展示化学物质的颜色,系统地科普物质背后的颜色成因。本文主要介绍了此款化学实物展架的设计理念、展示内容及其应用场景。     

介绍一个针对非化学专业的化学科普实验——头发中微量元素的测定

结合中国科学技术大学的学期改制,在夏季学期面向全校非化学专业的低年级本科生开设了“生活中的化学科普实验”公选课程,课程内容多为与生活密切相关的热点问题。“头发中微量元素的测定”是其实验项目之一。该实验将学生自己的头发作为分析对象,合理地设计教学内容和实验步骤,以期激发学生对化学实验的兴趣,提高学生对化学学科的认识。     

Alpha-activation analysis of boron on Si surface and in Si and SiO2 films

Brazil has become the largest producer of biomass ethanol derived from sugar cane. The industrial production is based on the fermentation of sugar cane juice by yeast, inside of large volume vats, in a fed-batch process that recycles yeast cells. To study the dynamics of chemical elements in each operating cycle, five stages of the fementation process were considered: must, yeast suspension, wine, non-yeast wine and yeast cream. For this, a mass balance of the terrigenous elements, Ce, Co, Cs, Eu, Fe, Hf, La, Na, Sc, Sm, and Th, and the sugar cane plant elements, Br, K, Rb, and Zn, were established in fementation vats of an industrial scale unit, with sampling undertaken during different climatic conditions (dry and rainy periods). A similar distribution of the sugar cane characteristics elements was found for the stages analysed, while for the terrigenous elements a trend of accumulation in the yeast cream was observed. Preferential absorption of Br, K, Rb, and Zn by yeast cells was indicated by the smaller concentrations observed in yeast suspension than in yeast cream.     

INTERFACIAL PHENOMENA IN FOOD EMULSIONS

The importance of proteins to provide steric stabilization of food emulsions is discussed. In aerated emulsions like ice cream and whipped cream, a partial destabilization of the fat globules is needed to obtain a satisfactory product. The destabilization process is controlled by surface active lipids (emulsifiers) which promote desorption of the interfacial protein film under specific temperature conditions. The formation of liquid crystalline films in o/w emulsions without proteins is also briefly discussed.     

聚丙烯酸辅助水热合成CdS纳米片

利用聚丙烯酸(PAA)和硫代乙酰胺(TAA)合成大分子硫源,采用水热的方法在180℃下制备立方相CdS纳米片,纳米片平均大小在100nm.用X射线衍射仪器(XRD),透射电子显微镜(TEM),红外吸收光谱(FTIR)和紫外吸收光谱(UV-Vis)对CdS纳米片进行了形貌和性能表征,并分析了CdS纳米片形成的可能机理.此外,反应的溶剂对CdS纳米材料的形貌有重要的影响.     

A study of the ageing of the gel structure in a nonionic O/W cream by X-ray diffraction,differential scanning calorimetry and spin-lattice relaxation measurements

The time dependent changes of the lamellar gel structure in a nonionic O/W cream were studied. It appeared that the changes were connected with alterations in the hydrophilic layers of this lamellar gel structure. The structure of the hydrocarbon layers did not change. The alterations were induced by an increasing hydration of the surfactant molecules on cooling from the preparation temperature to room temperature. Ageing of the cream involves a decrease of the thickness of the hydrophilic layers and a change of the distribution of the surfactant molecules, resulting in, among other things, a decrease of the release rate of a hydrophilic drug. Ageing of the cream can be prevented by using the appropriate amount of starting materials or by the use of polymerizable surfactants. In the former case a cream, from which a drug is slowly released, is obtained. On the other hand, creams containing polymerized surfactants can release drugs at a relatively high rate.     

新型液体介质二苄基甲苯的研制

二苄基甲苯具有沸点高、凝固点低、无毒、热稳定性和绝缘性好等特点,可用作热交换剂、绝缘油、塑料添加剂和光电导体材料等,是一种很有前途的新型液体介质。早在本世纪四、五十年代就有其合成方法报导。本文以甲苯和氯化苄为原料,用自制的AC—80络合物为催化剂研制了二苄基甲苯,用它作高温化学反应溶剂、电容器浸渍剂和塑料增塑剂已取得良好结果。     

新媒体时代下化学实验教学与实验室管理探索

当今新媒体时代下,二维码和公众号技术虽然已经普遍成熟,但是其在化学实验教学和实验室管理方面的深层次应用尚处于探索阶段。本文结合目前高校实验教学特点,分析探索了二维码和公众号技术在化学实验教学和管理中的应用以及存在的问题。从学生和教师两方面出发,在同为辅助工具的基础上两者联用不仅促进了实验教学平台整体的运行效率和管理水平,而且在充分发挥教师主导作用的同时调动了学生的主观能动性,学习效果及实际教学效果亦日渐显著,为国内化学实验教学改革提供了帮助。     

Effects of pre-irradiation with X-rays on the liquefaction of sugar cane bagasse

In a search for new energy and chemical feedstocks the pre-irradiation of sugar cane bagasse with X-rays before the conversion process has been studied. Different X-ray doses for the pre-irradiation process were used after which the samples were submitted to a liquefaction process. The product obtained was then submitted to a PLC-8 fractionation. It was verified that pre-irradiation to low doses increases the yield of the liquid product obtained. It was also observed that the product quality can be altered by controlling the irradiation process. An increase in the relative concentrations of hydrocarbons and resins as a function of pre-irradiation suggests the potential use of these fibers as feedstocks.     

板蓝根中提取靛蓝应用于扎染的创新实验教学——介绍一个大学化学综合教学实验

A comprehensive chemical teaching experiment was introduced, including extraction, separation, identification and application of Indigo plants. The indigo was extracted from Isatis root and applied to dying. The experiment involves several basic methods of natural product extraction, analytical chemistry procedures and its application. Through the experiment, students' research interest and exploring spirit will be stimulated, and experiment operation skills will be improved. This experiment was expected to be taught through lively activities, and outlined the relation between basic operation and production application.     

Techno-economic analysis of biocatalytic processes for production of alkene epoxides

A techno-economic analysis of two different bioprocesses was conducted, one for the conversion of propylene to propylene oxide (PO) and other for conversion of styrene to styrene epoxide (SO). The first process was a lipase-mediated chemo-enzymatic reaction, whereas the second one was a one-step enzymatic process using chloroperoxidase. The PO produced through the chemo-enzymatic process is a racemic product, whereas the latter process (based on chloroperoxidase) produces an enantio-pure product. The former process thus falls under the category of high-volume commodity chemical (PO); whereas the latter is a low-volume, high-value product (SO).A simulation of the process was conducted using the bioprocess engineering software SuperPro Designer v6.0 (Intelligen, Inc., Scotch Plains, NJ) to determine the economic feasibility of the process. The purpose of the exercise was to compare biocatalytic processes with existing chemical processes for production of alkene expoxides. The results show that further improvements are needed in improving biocatalyst stability to make these bioprocesses competitive with chemical processes.     

A never-ending search for the truth: Thermodynamics in the uncertain era of the internet

This article is based on the 20th Rossini Lecture delivered on 28 July 2014 at the opening of the 23rd International Conference on Chemical Thermodynamics in Durban, South Africa.In the last several decades, enormous progress in material and computer sciences has led, in many scientific disciplines, to fundamental improvements in experimental measurement technologies. That, in combination with new communication technologies and gradually increasing societal commitment to support public scientific research, has resulted in an unprecedented growth in the “production” of the reported experimental results. These trends together with dramatically growing demand for thermophysical and thermochemical property data related to new chemical processes and products necessitated development of dynamic methods of critical data evaluation within a framework of the concept of Global Information Systems in Science which was developed and implemented for the field of thermodynamics at the Thermodynamics Research Center (TRC) of the US National Institute of Standards and Technology (NIST). Principal advantages of this approach in comparison with the traditional static methods of critical data evaluation are illustrated.Major components of the developed system and its impact on such areas of human activities as information delivery, data publication, chemical process design, chemical product design, experiment planning, and education are discussed. The systems and software tools designed for global validation of experimental values are outlined. A variety of experimental data-driven technologies for thermophysical property prediction developed with the use of the elements of the Global Information System in Thermodynamics, including those based on surrogate mixture models, group contributions, QSPR, UNIFAC, and Monte Carlo molecular simulation, are described.