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1.
Conclusions 1. A. new route for the synthesis of optically active ,-diglycerides has been developed.2. D- and L-, -Distearins and D-, -dilinolenin have been synthesized from the readily accessible L- and D--O-tritylglycerols.Khimiya Prirodnykh Soedinenii, Vol. 5, No. 4, pp. 210–214, 1969  相似文献   

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综述了绿色化学的发展背景与历史,重点介绍了绿色化学反应的基本原则以及绿色化学在原子经济、绿色原料、绿色催化剂、绿色溶剂、绿色化学产品等领域取得的进展,希望能够推动社会和民众对绿色化学的理解与认知。  相似文献   

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有机化学知识在高分子化学教学中的应用   总被引:1,自引:0,他引:1  
<高分子化学>是研究聚合反应机理和聚合方法的一门科学,是高分子材料专业的一门重要专业基础课,它与前期所学课程<有机化学>课程有着非常紧密的联系.有机化学知识在高分子化学中的应用有利于调动学生的学习积极性,加深对教学难点的理解,以便提高教学质量,达到更好的教学效果.本文结合高分子化学和有机化学的课堂教学实践,就有机化学知识在辅助高分子化学教学过程中的应用提出了一些实例和自己的体会.  相似文献   

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The -electron charges, bond orders, and energy levels of phenoxazin-3-one and eight of its mono- and diannelated derivatives were calculated by the Hückel MO LCAO method. The effect of the position of the annelated benzene ring on the electronic characteristics of the compounds was estimated. A satisfactory correlation between the experimental and calculated energies of the 1 1 transitions was found.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1316–1322, October, 1970.  相似文献   

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The main aim of the paper is to reinforce the notion that emergence is a basic characteristic of the molecular sciences in general and chemistry in particular. Although this point is well accepted, even in the primary reference on emergence, the keyword emergence is rarely utilized by chemists and molecular biologists and chemistry textbooks for undergraduates. The possible reasons for this situation are discussed. The paper first re-introduces the concept of emergence based on very simple geometrical forms; and considers some simple chemical examples among low and high molecular weight compounds. On the basis of these chemical examples, a few interesting philosophical issues inherent to the field of emergence are discussed – again making the point that such examples, given their clarity and simplicity, permit one to better understand the complex philosophical issues. Thus, the question of predictability is discussed, namely whether and to what extent can emergent properties be predicted on the basis of the component’s properties; or the question of the explicability (a top down process). The relation between reductionism and emergentism is also discussed as well as the notion of downward causality and double causality (macrodeterminism); namely the question whether and to what extent the emergent properties of the higher hierarchic level affect the properties of the lower level components. Finally, the question is analyzed, whether life can be considered as an emergent property. More generally, the final point is made, that the re-introduction of the notion of emergence in chemistry, and in particular in the teaching, may bring about a deeper understanding of the meaning of chemical complexity and may bring chemistry closer to the humanistic areas of philosophy and epistemology. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

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化学学科的现状及基础化学教育改革问题   总被引:29,自引:0,他引:29  
宋心琦 《大学化学》2001,16(1):40-47
1 化学学科现状简介  自 1 80 2年道尔顿提出原子假说 ,1 81 1年阿佛加德罗又提出分子学说以来 ,化学一直在原子和分子学说的基础上发展着。 1 86 9年门捷列夫所发现的元素周期律及在此基础上构成的元素周期表 ,使化学从而成为一门有着严密体系的学科。由于当时对于原子和分子的结构理论还停留在假说的阶段 ,化学家的研究工作主要侧重于元素的发现、分析或分离组成复杂的样品的方法以及新化合物的合成 ,所以化学的传统定义中只强调合成和分析两个方面。这个传统在基础化学教育中至今仍然有着深刻的影响。 2 0世纪物理学家对原子结构及有…  相似文献   

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Summary 1. The synthesis of the following neutral plasmalogens has been effected: -O-(octadec-1-enyl)-, distearoylglycerol, -O-(octadec-1-enyl)-, -dipalmitoylglycerol, -O-(hexadec-1-enyl)-, -distearoylglycerol, and -O-(pentadec-1-enyl)-, -dipalmitoylglycerol.2. During the synthesis, the following compounds were isolated and characterized by their physicochemical constants: the -octadec-1-enyl ether of glycerol, -(2-hydroxyoctadecyl) , -isopropylideneglyceryl ether, the tosylate of -(2-hydroxyoctadecyl) , -isopropylideneglyceryl ether, and -O-(2-tosyloxyoctadecyl) glycerol.3. The IR spectra of the -octadec-1-enyl ether of glycerol and the neutral plasmalogens have been studied.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 6, pp. 367–371, 1966  相似文献   

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Summary A number of derivatives of androstano [3, 2-b] pyrylium and androst-13-eno-[3, 2-b] pyrylium derivatives forming a new class of heterocyclic steroids has been obtained.Khimiya Prirodnykh Soedinenii, Vol. 1, No. 5, pp. 318–321, 1965  相似文献   

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Summary A method for the separate quantitative determination of the furocoumarins ofFicus carica has been developed.Khimiya Prirodnykh Soedinenii, Vol. 3, No. 5, pp. 295–298, 1967  相似文献   

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酸是五味之一。食物酸味的产生是由于其中所含的酸性化合物。不同的酸味食物,所含的酸性化合物结构有所不同。从酸味的产生原理出发,对常见酸味食物中所含酸性化合物的结构及性质进行了介绍。  相似文献   

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This paper deals with pattern formation in Langmuir monolayers of two sets of lipid mixtures that include (1) a fluorinated lipid for phase separation, (2) a polymerizable lipid for stabilization of the patterned structure, and (3) a unit for the presentation of biological recognition units. Differences in the distribution of these functionalities allow a polymerization of dispersed or continuous phase and a placement of the recognition units in crystalline or solid analogue phase. Also, a ternary mixture including a lipid modified with the tandem repeat domain of MUC1 plus a TN-antigen was studied. Based on the biphasic pattern obtained (starlike crystals of up to 50 μm with a fine structure of some micrometers), we also verified the potential of the laterally patterned monolayer to stimulate the immune system (quartz crystal microbalance). The second set of lipids combines a highly fluorinated itaconic ester (polymerizable unit) with the natural phospholipid 1,2-dimyristoyl-sn-glycero-3-phosphoethanolamine.  相似文献   

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味觉化学之苦味化学*   总被引:1,自引:0,他引:1  
食物的苦味源于所含苦味的化学物质,按照生物碱、糖苷、多酚、萜、氨基酸和多肽及无机盐的结构分类,对常见的苦味化学物质进行了详细介绍。  相似文献   

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王彦吉  王景翰  王俭  史晓凡 《化学通报》2002,65(10):688-691
简单叙述了法庭化学与化学的关系,法庭化学是化学的一个特殊组成部分,化学的发展促进法庭化学的发展,法庭化学在侦破案件中起重要作用。本文还介绍了法庭化学研究的内容及与相关学科的关系。  相似文献   

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《Ambix》2013,60(3):135-154
Abstract

In Oxford Street a collegemet the eyes

of those who breathe the smoke of London skies,

Grand was its structure, noble was the place

Framed for the training of the rising race.  相似文献   

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石敏  姜雪峰 《化学教育》2020,41(16):1-8
甜,是一种令人愉快的味道,让人产生幸福的感觉,生物本质是甜味分子与甜味受体相互作用,经过复杂的传递过程然后激活大脑奖赏区释放神经递质多巴胺。从化学结构角度上看,甜味分子可分为:糖类(糖、糖衍生物、糖醇、糖苷),氨基酸类(二肽、蛋白质),磺酰胺类等,甜度值与分子结构密切相关。本文从分子结构层面阐述各类甜味分子及其甜度。  相似文献   

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基于Internet的化学学习模式与化学网络资源的利用   总被引:4,自引:0,他引:4  
《大学化学》2003,18(3):42-46
Internet技术的迅速发展 ,给化学教育带来了前所未有的冲击 ,为化学教育改革注入了活力。化学作为一门以实验为基础的学科 ,可以很好地与Internet技术结合 ,Internet巨大的信息资源的开发与利用已经发展成为一种能适应网络时代化学教育需求的全新的学习模式。分析并提出了基于Internet的网络教育的化学学习模式 ,以及如何在化学教育中深化网络信息资源的开发和利用。  相似文献   

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