《化学工程与工艺专业英语》课文翻译Unit 10 What Is Chemical Engineering
Unit 10What Is Chemical Engineering? 什么是化学工程学In a wider sense, engineering may be defined as a scientific presentation of the techniques and facilities used in a particular industry. For example, mechanical engineering refers to the techniques and facilities employed to make machines. It is predominantly based on mechanical forces which are used to change the appearance and/or physical properties of the materials being worked, while their chemical properties are left unchanged. Chemical engineering encompasses the chemical processing of raw materials, based on chemical and physico-chemical phenomena of high complexity. 广义来讲,工程学可以定义为对某种工业所用技术和设备的科学表达。
例如,机械工程 学涉及的是制造机器的工业所用技术和设备。 它优先讨论的是机械力, 这种作用力可以改变 所加工对象的外表或物理性质而不改变其化学性质。 化学工程学包括原材料的化学过程, 以 更为复杂的化学和物理化学现象为基础。 Thus, chemical engineering is that branch of engineering which is concerned with the study of the design, manufacture, and operation of plant and machinery in industrial chemical processes. 因此,化学工程学是工程学的一个分支,它涉及工业化化学过程中工厂和机器的设计、 制造、和操作的研究。 Chemical engineering is above all based on the chemical sciences, such as physical chemistry, chemical thermodynamics, and chemical kinetics. In doing so, however, it does not simply copy their findings, but adapts them to bulk chemical processing. The principal objectives that set chemical engineering apart from chemistry as a pure science, is “to find the most economical route of operation and to design commercial equipment and accessories that suit it best of all”. Therefore, chemical engineering is inconceivable without close ties with economics, physics, mathematics, cybernetics, applied mechanics, and other technical sciences. 前述化学工程学都是以化学科学为基础的,如物理化学,化学热力学和化学动力学。
近年来,不少学者应用关节内窥镜检查,可发现本病的早期改变,如关节 盘和滑膜充血、渗血、粘连以及未分化成熟的软骨样组织形成的“关节鼠”等。我们将“威胁代理”作为“应用描述”,“业 务影响”作为“应用/业务描述”,以说明这些依赖于您企业中应用的详细信息。算例3.4 应用:桥梁结构的ansys参数化分析3.4.1 桥梁结构描述3.4.2 基于ansys的桁架桥梁结构分析3.5 本章要点3.6 习题第4章 连续体结构分析的有限元方法4.1 连续体结构分析的工程概念4.2 连续体结构分析的基本力学原理4.3 平面问题有限元分析的标准化表征4.3.1 平面问题的3节点三角形单元描述4.3.2 平面问题的4节点矩形单元描述4.3.3 平面问题3节点三角形单。
许多早期的有关化学工程的教科书和手册都是那个时 候已知的商品生产过程的百科全书。 科学和工业的发展使化学品的制造数量迅速增加。 举例来说, 今天石油已经成为八万多种化学产品生产的原材料。 一方面是化学加工工业扩张的要 求,另一方面是化学和技术水平的发展为化学工艺建立理论基础提供了可能。 As the chemical process industries forged ahead, new data, new relationships and new generalizations were added to the subject-matter of chemical engineering. Many branches in their own right have separated from the main stream of chemical engineering, such as process and plant design, automation, chemical process simulation and modeling, etc. 随着化学加工工业的发展, 新的数据, 新的关系和新的综论不断添加到化学工程学的目 录中。
然后又从主干上分出许多的分支, 如工艺和工厂设计, 自动化, 化工工艺模拟和模型, 等等。 1. A Brief Historical Outline Historically, chemical engineering is inseparable from the chemical process industries. In its early days chemical engineering which came into being with the advent of early chemical trades was a purely descriptive division of applied chemistry. 1. 简要的历史轮廓 从历史上来说,化学工程学与化学加工工业密不可分。在早期,化学工程学随着早期化学产 品交易的发展而出现,是应用化学的纯描述性的分支。 The manufacture of basic chemical products on Europe appears to have begun in the 15th century when small, specialized businesses were first set up to turn out acids, alkalis, salts, pharmaceutical preparations, and some organic compounds. 在欧洲,基础化学产品的制造出现在 15 世纪。
一些小的、专门的企业开始创立,生产酸、 碱、盐、药物中间体和一些有机化合物。 For all the rhetoric of nineteenth-century academic chemists in Britain urging the priority of the study of pure chemistry over applied, their students who became works chemists were little more than qualitative and quantitative analysts. Before the 1880s this was equally true of German chemical firms, who remained content to retain academic consultants who pursued research within the university and who would occasionally provide the material for manufacturing innovation. By the 1880s, however, industrialists were beginning to recognize that the scaling up of consultants’ laboratory preparations, and syntheses was a distinctly different activity from laboratory investigation. They began to refer to this scaling problem and its solution as “chemical engineering”—possibly because the mechanical engineers who had already been introduced into works to who seemed best able to understand the process involved. The academic dichotomy of head and hand died slowly. 由于十九世纪英国的学院化学家强调纯化学的研究高于应用化学, 他们的要成为工业化学 家的学生也只是定性和定量分析者。
在 19 世纪 80 年代以前,德国的化学公司也是这样。他 们愿意聘请那些在大学里进行研究的人作顾问, 这些人偶尔为制造的革新提供一些意见。 然 而到了 80 年代,工业家们开始认识到要把顾问们在实验室的准备和合成工作进行放大是一 个与实验室研究截然不同的活动。 他们开始把这个放大的问题以及解决的方法交给 “化学工 程师” —这可能是受到已经进入工厂的机械工程师的表现的启发。 由于机械工程师熟悉所涉 及的加工工艺, 是维修日益复杂化的工业生产中的蒸气机和高压泵的最合适的人选。 学院研 究中头和手两分的现象逐渐消亡。Unit operation. In Britain when in 1881 there was an attempt to name the new Society of Chemical industry as the “Society of Chemical engineers”, the suggestion was turned down. On the other hand, as a result of growing pressure from the industrial sector the curricula of technical institutions began to reflect, at last, the need for chemical engineers rather than competent analysts. No longer was mere description of existing industrial processes to suffice. Instead the expectation was that the processes generic to various specific industries would be analyzed, thus making room for the introduction of thermodynamic perspectives, as well as those being opened up buy the new physical chemistry of kinetics, solutions and phases. 单元操作。
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