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关键词： Open-framework nanomaterials   Crystal-structure   Coordinated tin   Temperature   Thiostannate(iv)   Chalcogenides   Polytypes   Evolution   Snse  

摘要： Tin sulfide-based materials can exist in many forms, ranging from discrete molecular species, to 1D chains, 2D dense and porous sheets and 3D open frameworks. The local coordination geometry around a tin center may vary from trigonal pyramidal, to tetrahedral, trigonal bipyramidal and octahedral, and around sulfur from terminal, v-shaped to trigonal pyramidal. The oxidation state may take + 2 and + 4 for tin and -2, -1, 0 for sulfur. The tin sulfide chemistry is further enriched by the catenation ability of sulfur. In addition, other elements (metal and non-metal) can be incorporated into the tin sulfide structures to yield ternary and quaternary materials. More importantly, using the recent developed 'soft chemistry' synthetic approach, various novel porous tin (poly)sulfide materials have emerged that display interesting optical, electrical and adsorption properties. Representative tin sulfide materials will be presented and discussed in this review to demonstrate the development of tin sulfide chemistry in the last three decades.

关键词： 无机材料化学   固体化学   固态化学   定义   范畴  

摘要： 探讨了新兴的无机材料化学的命名、定义和范畴；分析了它在学科分类学中的地位；讨论了无机材料化学的源和流；回顾了该学科在我国的发展；提出了建议。

关键词： 镍   磷   聚四氟乙烯   化学镀   复合材料   镀镍  

摘要： 本文介绍了镍—磷—聚四氟乙烯复合材料化学镀层的条件，化学镀复合材料的镀液要求和特性，影响复合镀的主要因素，化学镀镍—磷—聚四氟乙烯复合镀层工艺。

关键词： AFP   antifreeze protein   AFGP   antifreeze glycoproteins   Ala   alanine   Asn   aspargine   Gin   glutamine   H   heavy   Ser   serine   Thr   threonine  

摘要： The study of biomineralisation and the biomimetic synthesis of inorganic materials with small-scale structures is a continuing area of growth because of the demand for inorganic colloids with ever decreasing particle sizes, complex morphological shape, hybrid structure and superlattice organisation. Some of the continuing advances are taking place at the interface between bio-inorganic and materials chemistry, with the focus on structures from single-celled biological systems that have dimensions from the supramolecular to those generally less than a few micrometres in size.

关键词： 金属间化合物   铁   铝   复合材料   化学相容性  

摘要： Ｆｅ－Ａｌ是一种金属间化合物新型结构材料，利用高强度、高模量的颗粒、纤维或晶须增强是进一步改善其性能的有效途径。本文提出一种方法，通过热力学计算预测增强相和基体的化学相容性，以方便进一步实验研究。

关键词： genetic algorithm   organic molecules   self assembly  

摘要： A genetic algorithm was designed in order to predict the low-energy conformations of organic molecules, particularly those of interest in the study of self assembly. The molecules of interest typically have many degrees of freedom so that it is difficult to minimize their conformational energies by conventional means. This has been our motivation in developing a genetic algorithm tailored specifically for efficient conformational search. The algorithm incorporates binary coding, fitness proportional selection, full generational replacement, N-point crossover, fitness scaling and niching. The algorithm was able to predict the minimum energy conformation of tricosane (C23H48) after only several thousand energy evaluations. Furthermore, the algorithm found low-energy conformations of self assembling molecules synthesized in our laboratory which match predictions based on X-ray and electron diffraction data. (C) 1998 Elsevier Science Ltd. All rights reserved.

关键词： polyphosphazenes   polysiloxanes   copolymers   films  

摘要： Catenapoly(dimethyl-lambda(5)-phosphazene-co-methylphenyl-lambda(5)-phospazene) functionalized by electrophilic substitution of a methyl hydrogen atom with reactive Si(OMe)(3) groups grafts easily to glass or cross-links to free-standing films by hydrolysis and further condensation of the silicon functional group. The manufactured films exhibit a high gas permeability.

关键词： 钢铁材料   化学清洗   酸洗   缓蚀抑制剂  

摘要： 钢铁材料在生产加工中,经常会涉及到防锈和除锈的问题.常用的除锈方法有机械除锈和化学除锈.化学除锈就是采用各种酸溶液来清除钢铁材料表面的氧化物.以硫酸为例,其清除钢铁材料表面的氧化物过程如下:FeO+H₂SO₄→FeSO₄+H₂OFe₃O₄+4H₂SO₄→FeSO₄+Fe₂（SO₄）₃+4H₂OFe₂O₃+3H₂SO₄→Fe₂（SO₄）₃+3H₂O但是,在清除铁的氧化物的同时,酸又把金属铁溶解了,使金属受到损失,

关键词： 诺贝尔化学奖   1996年   大学教授   布基球   球状结构   哈罗德   宇宙化学   化学研究   材料物理   材料化学  

摘要： 美国赖斯大学教授罗伯特·柯尔和理查德·斯莫利以及英国萨塞克斯大学教授哈罗德·克罗托获得了1996年诺贝尔化学奖。因为,他们在1985年发现了碳的球状结构——富勒式结构,其原子以6种晶体形式排列在封闭的框架中,其形状如一个球。这种结构的碳又被称为“布基球”。

关键词： 光谱解析   势能函数   计算机辅助教学   北京师范大学   配位场   材料化学   化学学会   中国化   分子科学   学会会员  

摘要： 李思殿,男,1959年生,山西省河津市人。现任生化系物理化学教授,中国化学学会会员,山西省化学学会常务理事。 李思殿的中小学时代恰逢十年动乱,他所接受的正规教育始于1978年进入运城师范,此后在中学任教三年。