具有好的溶解性和高的热稳定性的富勒烯-苝化合物的合成

在氩气保护下,利用N-(正丁基)-N’(4-甲酰基苯氧戊基)-1．6,7,12-四-(4-叔丁基苯氧基)-3,4,9,10-苝酰亚胺和N-甲基甘氨酸产生的亚胺叶立德与富勒烯反应,合成了含富勒烯的苝化合物,用NMR、FT—IR、UV-Vis及TGA等方法对其结构和性能进行了表征和测试。研究结果表明此类化合物具有好的溶解性和高的热稳定性。     

酯的水解实验的改进

该文对现行的高中化学 (试验修订本 )第二册中关于乙酸乙酯水解实验的不足之处进行了分析,并提出了改进的方法,对其实验内容和实验效果进行了讨论。     

基于压力的速率方程的应用

通过具体实例说明对于气相反应,使用基于压力的速率方程解题比使用基于浓度的速率方程更直接﹑更简便。总结了具有简单级数的反应的基于压力的速率方程及其特征。     

地球的内部可能是湿润的

在地球的低层地幔下 ,可能存在着比现在的海洋还要多 4倍的水 ,这是日本工业大学的Ｍ .Ｍｕｒａｋａｍｉ和他的同事们最近估测出来的。日本地球科学家们利用了一种多功能钻探仪 ,通过对 3种据信包含低层地幔中在高温高压下生成的主要矿物组成的分析后 ,得到了这个结论。这 3种矿物是 :Ｍｇ ｐｅｒｏｖｓｋｉｔｅ ,Ｃａ ｐｅｒｏｖｓｋｉｔｅ和Ｍａｇｎｅｓｉｏｗ櫣ｓｔｉｔｅ。再利用ＳＩＭＳ对矿物中溶解的氢的含量进行测量 ,矿物学家认为氢是水的标记。发现这3种矿物的含水量都相当可观 ,大约在 0 .2 %至 0 .4 %(重量比率 )之间。用红外…     

基于环糊精的农药吸附剂的研究进展

农药的研发与使用极大地提高了农作物的产量,为解决人类温饱、改善人类生活品质做出了贡献。但是,农药广泛残留于农副产品以及土壤和水体中,造成的污染日趋严重。残留的农药通常具有微量致毒、难生物降解、生物累积等特性,对生物健康与生态系统造成了巨大威胁。高效检测微量农药、减小污染危害是亟待解决的问题。吸附法具有成本低、操作简单、稳定性强、可重复性强的特点,在农药分离预富集领域得到了广泛关注。作为一种常用的农药吸附剂材料,环糊精是一类具有空腔的超分子化合物,能够作为主体通过主客体作用形成包合物;另外,可以通过醚化、酯化、氧化等化学反应对环糊精进行后修饰以提高其吸附性能。疏水作用、静电作用、范德华力、氢键作用、立体效应协同促进对农药的吸附。环糊精在农药吸附领域已经取得了一定进展,但是目前还没有基于环糊精的农药吸附剂的综述。该文针对杀菌剂、杀虫剂、除草剂、植物生长调节剂这4类农药,系统性地评述了基于环糊精的农药吸附剂的制备、吸附机理及应用,目前存在个别吸附剂吸附容量不高、降解机理不明确、降解产物对环境不友好、容易造成二次污染的问题,研发高吸附容量、易回收、易分离、易再生的基于环糊精的农药吸附剂是未来的主要研究方向。     

铁的吸氧腐蚀实验的改进

正1问题的提出化学实验是化学教学的生命线,在课堂教学中发挥着重要的认识论功能、方法论功能和教学论功能[1]。笔者在利用教科书中铁的吸氧腐蚀实验[2]进行教学时,如图1,发现该实验仅能让学生体会吸氧腐蚀的吸氧过程,而更核心的电化学过程却无法感受到。通过查阅近年文献,发现同仁们对该实验的研究更多关注如何缩短实验所用时间[3-6]。即便     

糖基修饰的氨基酸类化合物的合成

通过对5种氨基酸酯化和氨基保护得到苄氧羰基氨基酸甲酯, 经肼解制备苄氧羰基氨基酸酰肼, 然后分别与3种不同的糖基异硫氰酸酯反应, 制备了相应的目标化合物15个, 且产率均在60%以上. 所有新化合物均经元素分析, IR, MS和¹H NMR确证. 同时探索了苄氧羰基氨基酸甲酯肼解的最佳反应条件.     

基于Matlab的二元共聚合反应的竞聚率的求解

以直线交叉法为依据,根据最小二乘原理,采用Matlab GUI工具设计了一款用于计算二元共聚合反应竞聚率的图形用户程序。与传统的求解竞聚率方法相比,该图形用户程序具有设计原理简单、计算快捷的特点;同时程序提供界面简洁、交互友好的数据输入平台,实用性强。实际应用表明:采用该款图形用户程序所测得的数据与微机动态搜索法、Tidwell-Mortimer法相近,而比采用斜率截距法计算竞聚率的最小差方和更小,并且也避免了采用斜率截距法由于所用方程的非对称性造成的计算结果的不一致性。     

基于环糊精的新材料的研究进展

从纳米粒子、水凝胶、纤维材料和环糊精高分子等方面介绍了近年来以环糊精为基础研制的新材料的研究进展。目前以环糊精为基础的纳米粒子材料有核壳结构的纳米粒子、环糊精的化学接枝与共聚、环糊精与无机非金属材料的复合和含环糊精的囊泡材料;以环糊精为基础的凝胶材料有水凝胶和有机凝胶两种材料;此外还有以环糊精为基础的纤维材料、环糊精高...     

某些助剂对明胶的凝胶强度的影响的研究

众所周知,物理力学性能是照相明胶的一种很重要的属性。在各种彩色及黑白胶片都面向高温快速加工发展的今天,这种属性就显得更为重要。提高胶片的物理力学性能,一方面要从提高明胶本身的胶冻强度着手,例如减少明胶中溶胶组份(分子量小、冷水中溶解度高),提高明胶中的α和β组份的相对含量,减少分子量过大的组份等等。     

我国化学科普资源简介及类型分析

Fully understand the chemical science and reasonable use of existing resources is an important premise to chemical science popularization. This paper summarizes the current resource types of popular science of chemistry in China. The chemical science resources in China are sorted out and analyzed, including China Association for Science and Technology of chemical science, popular science base of scientific research institutes and universities, scientific public class and the chemical science online open courses, and WeChat public platform chemical resources. This paper will provide a meaningful introduction of chemical science resources for the public, and provide valuable reference for the practice of chemical science in China.     

Chemical information science coverage in Chemical Abstracts

For many years Chemical Abstracts has included in its coverage publications on chemical documentation or chemical information science. Although the bulk of those publications can be found in section 20 of Chemical Abstracts, many relevant articles were found scattered among 39 other sections of CA in 1984-1985. In addition to the scattering of references in CA, the comprehensiveness of Chemical Abstracts as a secondary source for chemical information science is called into question. Data are provided on the journals that contributed the most references on chemical information science and on the languages of publication of relevant articles.     

Breaking the law: promoting domain-specificity in chemical education in the context of arguing about the periodic law

In this paper, domain-specificity is presented as an understudied problem in chemical education. This argument is unpacked by drawing from two bodies of literature: learning of science and epistemology of science, both themes that have cognitive as well as philosophical undertones. The wider context is students’ engagement in scientific inquiry, an important goal for science education and one that has not been well executed in everyday classrooms. The focus on science learning illustrates the role of domain specificity in scientific reasoning. The discussion on epistemology of science presents ideas from the emerging field of philosophy of chemistry to highlight the much neglected area of epistemology in chemical education. Domain-specificity is exemplified in the context of chemical laws, in particular the Periodic Law. The applications of the discussion for chemical education are explored in relation to argumentation, itself an epistemologically grounded discourse pattern in science. The overall implications include the need for reconceptualization of the nature of teaching and learning in chemistry to include more particular epistemological aspects of chemistry.     

在解密“骗局”中推广化学科普知识*

“骗局”中也蕴含着丰富的化学知识。高校科普工作者可以在解密这些“骗局”中,推广化学科普知识。围绕5W 模式--“谁来科普”“要科普给谁”“如何科普”“科普什么”和“科普效果如何”等5个问题,尝试建立一种在解密“骗局”中推广化学科普知识的新思路。具体为:以青少年和老年人为重点科普对象,构建“老师+学生”共同实施、现场演示与讲解并重、新旧媒体联合传播、“效果指标体系”评价的科普模式,实现精准化学科普的目的。     

简论加强化学科技伦理教育的重要意义

化学科学与人类生活密不可分,对人类的可持续发展至关重要。若科技与伦理的关系不和谐,必定会影响到整个人类社会发展的和谐性。化学作为一门重要的自然科学,化学科技伦理在当前科技伦理教育中的重要地位日益突出,在教学中加强化学科技伦理教育具有非常重要的意义。     

我国化学科普的现状与创新发展对策

Chemistry is a central science. However, the public's recognition of chemistry needs to be promoted, and the prejudice needs to be reduced. Chemical science popularization is a long-term, complex and arduous social education project, which is of great significance to promote social harmony and improve people's quality of life. This paper summarizes the current status of chemical science popularization in China, and puts forward the innovative development countermeasures which focus on improving public participation, training popular science talents, carrying out popular science popularization education at different levels, creating high-quality science popularization works and opening up new positions and approaches of chemical science popularization. This paper has the reference value for the science popularization colleagues.     

Molecular Thermodynamics for Chemical Process Design

Thermodynamic properties are essential for quantitative process design to produce chemical products. Caloric properties are required for heat balances, but these properties are usually available or estimated easily. More important—and often much more difficult to estimate—are the chemical potentials of components in mixtures; it is these potentials which determine phase equilibria, as required for separation operations, and chemical equilibria, as required for chemical reactors and for separation operations based on chemical reactions. Molecular thermodynamics is an engineering-oriented science for calculating the desired chemical potentials from a minimum of experimental data. This applied science, based on classical and statistical thermodynamics, yields chemical potentials through models that are based on molecular physics and physical chemistry. Selected examples are cited to illustrate the applicability of molecular thermodynamics: group-contribution methods for obtaining chemical potentials in highly nonideal mixtures as required for distillation-column and process-safety design; equation of state for precipitation of uniform-sized crystals from supercritical fluids; molecular-orbital calculations to guide process development for alternatives to environmentally dangerous chlorofluorohydrocarbons; molecular-simulation calculations for separation of gas mixtures with porous adsorbents; equilibria in two-phase aqueous systems for separation of protein mixtures; and, finally, extended polymer-solution thermodynamics to guide synthesis of hydrogels suitable for protein recovery from soybeans and for novel drug-delivery devices.     

关于统计学中一个新兴化学分支学科的建立、定义和教育

本文追溯了统计学发展、建立中的大事, 陈述了它的定义及其化学分支发展、建立的梗概; 鉴于化学界对该新兴化学分支学科的名称长期存在争议, 提出了以化学统计学而不以化学计量学为该学科名称的理由, 把化学统计学定义为一个研究有关数据的收集或产生、描述、分析、综合和解释, 以获得新化学知识或信息的学科; 阐明了许多公认属于统计学的方法, 如显著性检验、方差分析、回归和相关, 以及一些尚未认定属于统计学的方法, 如模型建立、蒙特卡罗方法、傅立叶变换和人工神经网络, 都含有统计学5 个内涵中的一个或多个; 探讨了化学统计学家成长的模式, 认为当务之急是把化学统计学纳入化学专业的教学计划, 以培养懂统计学的化学家。     

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。     

化学体系随机共振现象的理论研究

化学体系中随机共振现象的特性、机理、本质和应用的研究是非常重要的前沿课题。综述中国科学技术大学非线性化学实验室,在化学体系随机共振现象的理论研究中,所取得的主要成果,并阐述化学体系随机共振现象研究中所提出来的若干重要问题：非均相化学体系中随机共振;化学体系中内信号随机共振;化学体系中多重随机共振;化学体系中随机共振的调制;化学体系中色噪声作用下的随机共振;化学体系中时空随机共振;耦合化学体系中随机共振;化学体系中双参量随机共振。