专业外语英语加汉语Unit4ChemistryandAdvancedMaterial.doc

Unit 4 Chemistry and Advanced Materials 化学及先进材料 Chemistry of Advanced Materials 先进材料的化学Stone, bronze, iron: civilization has always been defined by Mans relationship with materials. nowadays, materials have become such an integral part of our society, that they are often either underappreciated or even overlooked. But much of the technological progress is directly or indirectly dependent on the availability of advanced materials with improved functions. It is often forgotten that there is much chemistry behind these investigations! 石、铜、铁:文明历来被认为是与人类息息相关的材料.如今,材料已成为当今社会的组成部分,它们往往也不能受到重视甚至被忽略。但是大多数的技术进步是直接或间接依赖于所能获得的先进材料以改善功能。这些调查系统背后是有许多化学反应，这是经常被遗忘的!Being closely related to materials science, chemistry focuses on the atomic or molecular level, and materials science deals with macroscopic properties, however both together provide a proper understanding of how chemical composition, structure and bonding of materials are related to the particular properties.与材料科学紧密相关的化学关注原子或者分子水平以及材料科学设计到的宏观性质。然而，两者一起可以理解材料的化学组成、结构和化学键如何同具体的性质联系起来。In the earlier days of civilization, especially in the production of metals, chemistry was only used empirically for the processing of materials, far from any understanding of the basic concepts. But many arising problems like pollution of the environment or the toxicity of different materials nowadays clearly reveal the need of a better understanding of the basic chemistry. It is becoming widely recognized that no new method for extracting or processing a material can be considered without good understanding of the real costs as well as its fate after its lifetime.在早期的文明,特别是在生产金属材料和仅以经验进行化学处理的材料,不能理解基本概念。但是许多出现的问题，像现在的环境污染、不同材料的毒性，清晰地显示需要很好地理解基础化学。如果不能很好的理解产品的真实成本和用完以后的处置，那么就不能考虑出新的提取或者加工材料的方法，这一点已经为大家所公认。A number of important aspects have to be investigated for example whether the required properties can be achieved and maintained during the use of a material, whether the material is compatible with other parts of an assembly, whether a material can be easily recycled, whether a material causes environmental problem, and whether a material can be produced economically.许多重要的方面必须加以调查，比如:是否材料要求的性质能否达到并且在使用过程中得到保持，是否材料同组装的其他部分相协调，是否材料能够容易地回收，是否材料会导致环境问题，是否材料可以很便宜的生产。Taking the fact into account that most of the processes during the life-cycle of a product are typically chemical reactions， it becomes obvious，that the solution of fundamental materials science problem is intimately interconnected with our knowledge in chemistry.在产品的一生中，大多数加工工艺是典型的化学反应，很明显，解决基本材料科学问题的方法紧密的同我们在化学方面的知识紧密地联系起来了。Only a better understanding of the chemicals concepts involved in materials life-cycle leads to substantial improvements in materials technologies. The understanding of the nanostructure of materials will be an essential part of such an enterprise. But the complexity and interdisciplinary nature of material science and engineering requires effective cooperation between scientists and engineers from various disciplines. 只有更好的了解化学在材料生命周期实质的相关概念才可以提高材料的技术。对于一个企业纳米材料的解释将占据着主要部分。但复杂性和跨学科性质的科学和工程需要科学家和工程师之间的有效合作从各种各样的学科来解释。Solid State Chemistry and Nanochemistry 固态化学和纳米化学In general, research in solid state chemistry is concerned with investigations of synthesis, structures and properties of solidsThe most important motivation is to understand，to predict, and to design the properties of solids with respect to both，chemical composition and their crystal and electronic structures.通常，在固体化学中的研究是参与研究固体材料的合成、结构和性质。最重要的目的是根据化学组成和它们的晶体和电子结构，去理解、预测和设计固体材料的性质。Of course, the first step is the synthesis of the required material. Three different categories of solid state synthesis can be distinguished depending on the motivation:i) preparation of known compounds to investigate a specific property;ii) synthesis of unknown members in a structurally related family in order to extend structure-property relations;iii) synthesis of new classes of solids.当然,第一步是合成所需的资料。三种不同类别的固态合成可以分为视动机:1. 制备已知化合物的一个特定的性能;2.合成未知结构的同系物是为了延伸结构-性能关系的关系;3. 合成新的固体Thus，solid state chemistry is mainly concerned with the development of new synthesis methods，new ways of identifying and characterizing materials and of describing their structureIn the last few years, the key direction of solid state chemistry lay in the search for new strategies of tailor-making materials with desired and controllable properties这样，固体化学主要参与开发新的合成方法、新的识别和表征材料的方法和描述它们的结构的新方法。在最近几年，固体化学的重点方向在于找到具有预期的和可控制的性能的特制材料的新的手段。Although there have been major advances in the synthesis of solid materials due to many new chemical methods, we are still far away from a tailor-making of solid materials with specified structures/properties. Most of the discoveries of new solids still have been made by chance! Therefore, rational design and synthesis of novel materials have remained important objectives. The control over the composition is often possible, but still then there must be a way of producing materials in any required micro and nanoscopic shape or form. At the same time, the characterization of materials is a critical ingredient to progress, because it provides guidance for further research efforts.在合成固体材料上虽然已经取得了重大的进展,由于许多新的化学方法,我们仍远离特定固体材料的指定结构或性能。大多数被发现的新固体都是偶然被制造出来的!因此,合理的设计和合成新型材料依然是重要的目标。构成的控制往往是可能的,虽然这样但是一定要有办法让任何需要的生产材料拥有微观和纳米形状或形式。与此同时,表征材料的进步是一个关键的成分,因为它提供指导,为进一步研究工作。In the last few years， solid state chemists started to exploit a combination of covalent and non-covalent interactions， i.e. they started to connect molecular chemistry，the chemistry of the covalent bond，with supramolecular chemistry， based on non-covalent, intermolecular forces (electrostatic interactions, hydrogen bonding, van der Waals forces)过去几年间，固体化学家开始开发以共价键和非共价键结合的化合物，比如，他们开始把分子化学（共价键化学）同基于非共价键、分子间作用力（静电作用、氢键、范德华力）的超分子化学连接起来。Molecular chemistry is concerned with uncovering and mastering the rule that govern the structure, properties, and transformations of molecular species，whereas the supramolecular chemistry is covering the structures and functions of organized entities higher complexity formed by association of two or more chemical species held together by intermolecular forces. These polymolecular assemblies may lead to supramolecular devices, defined structurally organized and functionally integrated chemical systems built on supramolecular architectures.分子化学主要参与揭露和掌握控制结构、性质和分子式样转变的规则，然而，超分子化学含盖了两种或两种以上化学物质通过分子间作用力连接起来的高度复杂的组织实体的结构和功能。这些多分子组件可能导致超分子设备,定义组织结构和功能的综合性化学系统建立在超分子体系结构上。From molecular to supramolecular chemistry, nanochemistry is the pursuit of this development of bottom-up synthesis of complex objects. 从分子到超分子化学、纳米化学是为了追求这自下而上的合成复杂对象的发展。The nanochemists future goal is to built and organize nanoscaIe objects under mild and controlled conditions finalIy of one cluster of atoms or even one atom at a time instead of manipulating the bulk，thus，providing a reproducible method of preparing materials that are perfect in size and shape.纳米化学家将来的目标是在温和的和控制的条件下，一次而不是成批的操作建立和组织一团原子或者一个原子的纳米分子水平物体，这样，提供了一个可重复的材料制备方法，这些材料在尺寸和形状上都有很好的性质。Nowadays, one would call this directed self assembly.At present，nanochemistry is concerned with the development of novel methods for the synthesis and characterization of chemical systems within the size range of about 1nm to 100nm. The interest in nanoscaIe objects is due to the exhibition of novel electronic，optical，magnetic, transport，photochemical, electrochemical，catalytic and mechanical behaviors，depending on composition，size，and shape of the particles. 如今,人会称这为自行组装。目前，纳米化学是开发新的制备表征化学系统的方法，这些化学系统在1纳米到100纳米尺寸范围内。纳米尺度物体的兴趣在于：它们显示出新的电的、光的、磁的、传输的、光化学的、电化学的、催化的和机械性能，取决于粒子的组成、尺寸和形状。The physical properties of nanoparticles neither correspond to those of the free atoms or molecules making up the particle nor to those of the bulk solids with identical chemical composition. It is astonishing, that many relevant phenomena at nanoscale are caused by the organized structure and by interactions at their predominant and complex interfaces. When the chemists are able to gain control over size and shape of the particles, further enhancement of material properties and device functions will surely be possible.纳米粒子的物理性质既不与那些自由的原子或构成分子的粒子有关也不与那些有相同的化学成分的大颗粒固体有关。在纳米尺度的许多相关的现象由有组织的结构、它们最主要的和复杂界面上的相互作用引起的，这点是特别惊奇的。当化学家能能掌控的微粒的大小和形状，进一步的提高材料的特性和设备功能一定会成为可能。Each change in both，composition or size can lead to different physical and chemical properties，providing a large number of new materials. Interestingly，it is true that the product of nanochemitry exhibit new and useful properties, but at the same time it is not necessarily a need for new starting materials: new applications and properties are rather a result of tailoring matter and subsequently arranging the components by means of chemical interactions，so，ideally, new properties can arise from a combination of inexpensive and environmentally harmless components. 在组成或者尺寸上的每一个变化可以导致不同物理和化学性质，这就提供了大量的新材料。有趣的是，纳米化学的产品显示出新的和有用的性质，但是同时，又不需要开发新的材料：借助于化学相互作用，通过特制物质和排布相应的组成，就可以得到新的应用和性质，理想状况下，把便宜的和环境无害的成分组合起来，就可以出现新的性质。At present the field of nanochemistry includes (i) nanoparticles, (ii) nanocrystalline materials and nanodevices. (iii)The most important aspect is still the development of new strategies for the synthesis of nanomaterials, particularly soft chemical routes.目前纳米化学领域包