专业英语课后作业翻译Lesson 4 Introdution Organic Chemistry(p59)有机化学简介Because of the tremendous number of organic compounds known, and of the many more being synthesized daily, the study of organic chemistry is not the study of individual compounds , it is the study of groups or families of compounds all closely related to each other. Obviously, the former approach would be prohibitive. Once the structural relationships of certain typical member of a particular group or family are understood, these structural features are understood for any one of the many members of the family even though some may not be known compounds, For each group of family of compounds often called homologous sreies of compounds, structureal features are improtant. In studying organic chemistry, it is not enough to know the identities of the elements and how many atoms of each element are present in a given molecule. More improtantly, the order in which these atoms are linked together to form the molecule must aslo be known, Once the identities of the element and the number of atoms prsent in each of these element have been established, structural studies are quite improtant. They require considerable effort and ingenuity on the part of the organic chemist.因为已知的有机化合物的数目庞大，而且还在逐日合成更多的品种，所以有机化学不是研究单个的化合物，而是把彼此密切相关的化合物按类或族来研究。
显然，以前的方法是不可取的，一旦典型的一类特殊化合物被认识，这些结构特征将适用于这类化合物，甚至是一些未知的化合物，对于一类化合物经常称其为同系物。
结构特征是非常重要的，只知道分子含有的元素和元素的原子个数是不够的，更重要的是知道原子组成分子的连接顺序，当元素及原子个数被确认之后，结构的研究也是很重要的，这些都需要有化学家的努力和聪明才智。
In summary, the following four steps are required in order to completely indentify any organic compound isolated for the first time from a natural source or produced for the first time in the laboratory:总而言之，为了能完全区别那些第一次从自然资源中分离或是从实验室中生产出来的有机化合物，以下四个步骤是必须的：( 1 ) Isolation of the compound from the mixture of organic or inorganic compounds among which it may be found , followed by application of appropriate criteria of purity.( 1 )从被发现的有机或无机化合物中分离出来的物质，运用适当的标准检验其纯度。
( 2 ) Establishment of its empirical and molecular formulas by use of appropriate methods of qualitative analysis, quantitative analysis, and molecular weight determination.( 2 )使用适当的定性、定量分析法和测定分子量来确立实验式。
( 3 ) Proposal of a structural formula as the result of appropriate chemical and physical examination of the compound.( 3 )通过对化合物进行适当的物理和化学测定，从而提出分子的结构式。
( 4 ) Synthesis of the compound by an unambiguous method as confirmation of the proposed structural formula.( 4 )用清晰的方法合成化合物来验证所提出的结构式Lesson 11 macromolecules(P91)大分子Historical Background历史背景：It would not be appropriate to complete a study of the subject of organic chemistry without including an introduction to the chemistry of macromolecules, and their preparation and properties . Macromolecules ,as the name implies, are molecules much larger than the simple ,small molecules that the subject of organic chemistry has dealt with thus far. The term high polymer is also used to identify these large molecules .High polymers are materials possessing an average molecular weight above 10000.在不包括大分子化学及其制备和性质的情况下，去完成有机化学这一学科的学习是不恰当的。
大分子，顾名思义，它的分子比目前为止已在有机化学中所涉及的那些简单小分子要大得多。
另一术语高聚物也用于表示大分子。
高聚物就是这样一些平均分子量大10000的材料。
Organic chemists are inclined to refer to certain structures as “dimers”“trimers ”“tetramers”,etc. The rapid development of the plastics, rubber,and synthetic fiber industries during the past several decades has created such a demen for chemists to work in these areas that, at the present , approximately half of the chemists in the United States ultimately do research or development work in the polymer field 有机化学家倾向于把特定结构的物质称为二聚物三聚物四聚物等等，在过去几十年里塑料橡胶以及合成纤维的快速度发展创造需求，使化学家投入到这片领域。
目前，大约有一半的美国的科学家在这里研究和工作。
Lesson26 Development of the Detergent Industry(1)P150洗涤剂工业的发展Although the start of the synthetic detergent industry is not shrouded in the veils of history as were the beginnings of the soap industry, it is nevertheless not easy to pinpoint exactly when the detergent industry ,as such ,came into being. The primary problem is to decide exactly what is being referred to as a synthetic detergent .The term itself leads to confusion .In the USA the words surfactant or syndet are being used ,whilst in Europe the term “tenside”(for tension-active mateial) is coming into fashion.合成洗涤剂工业何时问世？在历史上虽不像肥皂工业那样模糊不清，但要截然划清洗涤剂工业的始创年代确实不易。
最基本的问题是要精确定义什么物质能够被称为合成洗涤剂。
这个术语本身导致了混淆。
在美国，表面活性剂或合成洗涤剂正在被人们使用中，而在欧洲“表面活性剂”（即表面张力活性材料）也变得流行起来。
Lesson27 Development of the Detergent Industry(2)P156洗涤剂工业的发展Methods of test were developed and it was in fact, proved that linear alkyl benzene is biodegradable. Germany introduced legislation prohibiting the discharge of non-biologically degradable material into sewer systems. In the USA detergent manufacturers agreed voluntarily to switch over from PT benzene to linear alkyl benzene by June 1965. In the United Kingdom a similar t ype of “gentleman’s agreement ” was entered into.测试方法的开发实际上证明了线性烷基苯是可生物降解的。