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991.
8—羟基喹啉的高分子化及其应用展望   总被引:8,自引:0,他引:8  
综述了8-羟基喹啉的各种高分子化方法,介绍了其在分析,环境,材料等领域中的应用情况,并展望了其在有机电致发光领域和导电聚合物等领域中的应用前景,提出了一些与之相关的值得深入研究的问题。  相似文献   
992.
An effective solid-phase preparation of anilides from supported carboxylic acids is described by their activation as the corresponding acid chlorides with TMUCl Cl.  相似文献   
993.
分子印迹聚合物的设计合成   总被引:10,自引:0,他引:10  
分子印迹法是制备对特定分子(印迹分子)具有识别选择性的聚合物的技术,近年来,分子印迹法制得的聚合物在分离,分析,免疫测定,催化、模拟酶及生物传感器等方面的应用引起人们的广泛关系。本文介绍了分子印迹技术的基本原理,对分子印迹聚合物合成研究的最新进展进行了综述,评述了各种制备方法的优缺点,拽出了合成技术未来的发展方向。  相似文献   
994.
The liquid crystalline behavior of low molecular weight compounds has been known for more than a century; synthetic polymers have been manufactured on a large scale for several decades, but just recently it was found possible to produce polymers using the structural principles of liquid crystalline compounds. The resulting materials have, as expected, unusual properties. Numerous applications, not only in opto-electronics, are already anticipated for such materials.  相似文献   
995.
Trityl chloride (triphenylmethyl chloride, TrCl, Ph3CCl) is utilized as an efficient and homogeneous organocatalyst for the synthesis of 14‐aryl‐14H‐dibenzo[a,j]xanthenes from β‐naphthol and arylaldehydes under solvent‐free conditions. Moreover, a plausible mechanism is suggested based on the literature and on in situ formation of trityl carbocation with inherent instability during the reaction.  相似文献   
996.
Five styrenic monomers, four with aminoalkyl residues typical of copper containing amine oxidase substrates and one with a 2,6-dialkoxybenzylamine residue which mimics previously prepared selective substrate-like benzylamine oxidase inhibitors, have been synthesized and transformed into radical homopolymers, copolymers with N,N-dimethylacrylamide (DMAA), and hydrophilic beaded resins, designed for enzyme interaction studies aimed in finding new materials for highly biospecific chromatographic separations. The five monomers have given beaded resins of 125-500 μm swellable in water with a volume increase of 1200-1500%. The four aminoalkyl monomers have given water soluble copolymers some of which are good substrates of benzylamine oxidase (BAO), diamine oxidase (DAO) and lysyl oxidase (LO), up to 9.7 times better than elastin for LO.  相似文献   
997.
150×3 mm I.D. columns, packed with 1-μm non-porous spherical silica particles, were used to separate soluble synthetic polymers by hydrodynamic chromatography. The columns exhibited a plate height of about 1.4 μm allowing very fast and efficient separations of polymers in the molecular mass range 103−2·106 g/mol. The migration behaviour of polymers could be well described by a simple theoretical model. The applicability of packed bed HDC for the fast separation of polymers was illustrated with separations of polystyrene and poly(methyl methacrylate) mixtures.  相似文献   
998.
The Part and the Whole. The principle of self-organization for the creation of functional units is not an invention of modern natural sciences. It was already a basic idea of the ancient philosophies in Asia and Europe: only the mutuality of the parts creates the whole and its ability to function. Translated into the language of chemistry this means: the self-organization of molecules leads to supramolecular systems and is responsible for their functions. Thermotropic and lyotropic liquid crystals are such functional units, formed by self-organization. As highly oriented systems, they exhibit new properties. The importance of lyotropic liquid crystals for the life sciences has been known for a long time. They are a prerequisite for the development of life and the ability of cells to function. In materials sciences this concept of function through organization led to the development of new liquid-crystalline materials. From the point of view of macromolecular chemistry, this review tries to combine these two different fields and especially hopes to stimulate their interaction and joint treatment. To exemplify this, the molecular architecture of polymeric organized systems will be discussed. Polymeric liquid crystals combine the ability to undergo spontaneous self-organization–typical of liquid-crystalline phases–with the polymer-specific property of stabilizing these ordered states. As new materials, polymeric liquid crystals have already been investigated intensively. As model systems for biomembranes as well as for the simulation of biomembrane processes, they so far have been little discussed. The intention of this review article is to show that polymer science is able to contribute to the simulation of cellular processes such as the stabilization of biomembranes, specific surface recognition, or even the “uncorking” of cells. Polymer science, having an old tradition as an inter-disciplinary field, can no longer restrict itself to common plastics. Attempts to reach new horizons have already begun. The borderland between liquid crystals and cells will certainly play an important role. Basic requirements to work in this frontier area between organic chemistry, membrane biology, life science, and materials science will be the delight in scientific adventures as well as the courage to go ahead. The most important prerequisite will be the willingness to cooperate with disciplines which so far have not really accepted each other. From this point of view, this review does not aim at giving defined answers. It wants instead to encourage the scientific venture: too often we cling to painfully acquired knowledge, fearing adventures.  相似文献   
999.
覃丽君 《化学教育》2021,42(20):96-101
1999年,麻省理工学院启动了化学工程实践博士项目,迄今已有20余年的历史。该项目是麻省理工学院的独创,其模式较为新颖,有典型性与代表性。该模式突破了钟摆现象二元分割范式的制约,体现出跨学科多元整合的特色。在实践中,多元整合的特色体现在历史演进、培养目标、培养内容及培养路径方面。在新一轮工业革命竞争日趋激烈的背景下,创新高层次化学相关专业研究生人才培养模式意义重大。可运用跨学科多元整合模式,从树立多样化人才培养理念、打造跨学科教师队伍、构建校企协同育人机制等方面出发,打破化学相关专业研究生高层次人才培养的二元分割范式,整合多重资源,创新人才培养新理念,构建新时代化学工程研究生人才培养新模式。  相似文献   
1000.
在三乙胺作碱的条件下 ,用三苯基氯化锡和 2 ,6 -吡啶二甲酸以 1∶ 1摩尔比反应 ,合成了离子型有机锡化合物 { [Ph2 Sn]2 [2 ,6 -Py( CO2 ) 2 ]3 H2 O} 2 - [HNEt3 ]+2 。用 X-射线单晶衍射测定了该化合物的晶体结构。化合物为单斜晶系 ,空间群 P2 1 /n,a=1 .70 73( 7) nm,b=1 .74 47( 7) nm,c=2 .4 333( 1 0 ) nm,β=1 0 9.6 94 ( 7)°,Z=4 ,V=6 .82 4 ( 5 ) nm3 ,Dx=1 .2 82 g/cm3 ,μ=0 .793mm- 1 ,F( 0 0 0 ) =2 6 96 ,R1 =0 .0 5 6 3,WR2 =0 .1 5 39。化合物中两个锡原子呈七配位畸变五角双锥构型  相似文献   
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