专业英语翻译

UNIT1

Although the use of chemicals dates back to the ancient civilizations, the evolution of what we know as the modern chemical industry started much more recently.

尽管化学品的使用可以追溯到古代文明时代，我们所谓的现代化学工业的发展却是非常近代（才开始的）。

It may be considered to have begun during the Industrial Revolution, about 1800, and developed to provide chemicals roe use by other industries.

可以认为它起源于工业革命其间，大约在1800年，并发展成为为其它工业部门提供化学原料的产业。

Examples are alkali for soapmaking, bleaching powder for cotton, and silica and sodium carbonate for glassmaking.

比如制肥皂所用的碱，棉布生产所用的漂白粉，玻璃制造业所用的硅及Na2CO3. 我们会注意到所有这些都是无机物。

At the start of the twentieth century the emphasis on research on the applied aspects of chemistry in Germany had paid off handsomely, and by 1914 had resulted in the German chemical industry having 75% of the world market in chemicals.

20世纪初，德国花费大量资金用于实用化学方面的重点研究，到1914年，德国的化学工业在世界化学产品市场上占有75%的份额。

UNIT2

Research and development, or R&D as it is commonly referred to, is an activity which is carried out by all sectors of manufacturing industry but its extent varies considerably, as we will see shortly.

研究和开发，或通常所称R&D是制造业各个部门都要进行的一项活动。我们马上可以看到，它的内容变化很大。

Although the distinction between research and development is not always clear-cut, and there is often considerable overlap, we will attempt to separate them.

尽管研究和开发的定义总是分得不很清楚，而且有许多重叠的部分，我们还是要试着把它们区分开来。

In simple terms research can be thought of as the activity which produces new ideas and knowledge whereas development is putting those ideas into practice as new process and products.

简单说来，研究是产生新思想和新知识的活动，而开发则是把这些思想贯彻到实践中得到新工艺和新产品的行为。

To illustrate this with an example, predicting the structure of a new molecule which would have a specific biological activity and synthesizing it could be seen as research whereas testing it and developing it to the point where it could be marketed as a new drug could be described as the development part.

可以用一个例子来描述这一点，预测一个有特殊生物活性的分子结构并合成它可以看成是研究而测试它并把它发展到可以作为一种新药推向市场这一阶段则看作开发部分。

We can pick out a number of areas of R&D activity in the following paragraphs but if we were to start with those which were to spring to the mind of the academic, rather than the industrial, chemist then these would be basic, fundamental (background) or exploratory research and the synthesis of new compounds.

我们可以在后面的段落里举出大量的R&D活动。但是如果我们举出的点子来源于研究院而不是工业化学家的头脑，这就是基础的或探索性的研究

Aspects of synthesis could involve either developing new, more specific reagents for controlling particular functional group interconversions, i.e. developing synthetic methodology or complete synthesis of an entirely new molecule which is biologically active.

通过合成可以生产出一些新的、更特殊的试剂以控制特殊的官能团转换，即发展合成方法或完成一些具有生物活性的新分子的合成。

UNIT3

The classical role of the chemical engineer is to take the discoveries made by the chemist in the laboratory and develop them into money--making, commercial-scale chemical processes.

化学工程师经典的角色是把化学家在实验室里的发现拿来并发展成为能赚钱的、商业规模的化学过程。

The design stage is really where the big bucks are spent. One typical chemical process might require a capital investment of $50 to $100 million. That’s a lot of bread! And the chemica l engineer is the one who has to make many of the decisions.

设计阶段是大把金钱花进去的时候。一个常规的化工流程可能需要五千万到一亿美元的资金投入，有许多的事情要做。化学工程师是做出很多决定的人之一。

When you find yourself in that position, you will be glad that you studied as hard as you did (we hope) so that you can bring the best possible tools and minds to bear on the problems.

当你身处其位时，你会对自己曾经努力学习而能运用自己的方法和智慧处理这些问题感到欣慰。

Flow sheets are diagrams showing all the equipment schematically, with all streams labeled and their conditions specified (flow rate, temperature, pressure, composition, viscosity, density, etc.)

工艺流程图。是显示所有设备的图纸。要标出所有的流线和规定的条件（流速、温度、压力、构造、粘度、密度等）。

Equipment specification Sheets are sheets of detailed information on all the equipment precise dimensions, performance criteria, materials of construction, corrosion allowances, operating temperatures, and pressures, maximum and minimum flow rates, and the like. These “spec sheets” are sent to the equipment manufacturers for price bids and then for building the equipment.

仪器设备说明书。详细说明所有设备准确的空间尺度、操作参数、构造材料、耐腐蚀性、操作温度和压力、最大和最小流速以及诸如此类等等。这些规格说明书应交给中标的设备制造厂以进行设备生产

UNIT6

Historically the bulk chemical industry was built on chlor-alkali and related processes．The segment is normally taken to include the production of chlorine gas，caustic soda (sodium hydroxide),soda-ash (derivatives of sodium carbonate in various forms ) and，for convenience，lime based products．

纵观历史，大众化学品工业在氯碱及其相关过程之上。该部分通常包括氯气、苛性苏打（氢氧化钠）无水碳酸钠（以各种形式存在的碳酸钠的衍生物），以及以石灰为基础的产品。

The peculiar economics of electrolytic processes mean that you have to make totally different

types of product, and this causes swings in the price of caustic soda which can render soda-ash more or less favorable as an alkali.

电解过程的特殊经济性意味着不管对氯气和氢氧化钠这两种不同类型的产品的相对需求量如何，你只有以固定的比例同时制备氯气和氢氧化钠。这引起了氢氧化钠的价格的摇摆不定，从而使得纯碱作为一种碱或多或少有利。

One of the key raw materials is lime. Limestone consists mostly of calcium carbonate (CaCO3)laid down over geological time by various marine organisms.

一种关键（重要）原料是石灰石。石灰石主要是由CaCO3 组成，高质量的石灰石可直接用于下一步反应。

About 40% of the output in iron ore to give a fluid slag which floats to the surface and is easily separated from the liquid metal. Smaller, but still significant, amounts are used in chemical manufacture, pollution control and water treatment. The most important chemical derived from lime is soda-ash.

大约40%的石灰工业的产品用于钢铁制造业。在钢铁制造业中，纯碱用来与铁矿石中难溶解的硅酸盐反应，生成流态矿渣，矿渣漂浮于表面上，很容易从液态金属中分离，叫少量但重要的石灰工业的产品用于化学品的制造，污染控制和水处理。从石灰石得到的最重要的化学茶品是纯碱。

The Solvay process. The process, which was perfected by Ernest Solvay in 1865, is based on the precipitation of NaHCO3 when an ammoniated solution of salt is carbonated with CO2 form a coke-fired lime kiln. The NaHCO3 is filtered, dried, and calcined to Na2CO3.

索尔维工艺，该工艺发现于1865 年由ES 优化：工艺是以当含氮的盐溶液经来自于石灰窑中焦炭燃烧产物CO2 碳酸盐反应时，NaHCO3 沉淀析出为基础。NaHCO3 经过滤、干燥、煅烧生成CaCO3。

The filtered ammonium chloride process liquor is made alkaline with slaked lime and the ammonia is distilled out for recycle to the front end of the process. The resultant calcium chloride is a waster or by-product stream.

过滤后NH4Cl溶液和熟石灰反应后（溶液体呈碱性）。蒸馏出NH3 在该过程中循环利用，生成物CaCl2 是废弃物或副产物。

The essential principle is that, by carefully controlling the concentration of the components (especially ammonia and salt), sodium bicarbonate can be precipitated from solutions containing salt, carbon dioxide and ammonia, The key to making the process work is controlling the strength of the solutions and the rates of crystallization.

该过程的基本原理为：利用准确的控制组分（尤其是NH3 和NaCl）的浓度，NaHCO3 能够从含NaCl、CO2 和NH3 的溶液里沉淀析出。该过程的关键是控制溶液的酸碱强度和结晶的速度.

UNIT7

Dinitrogen makes up more than three-quarters of the air we breathe, but it is not readily available for further chemical use. Biological transformation of nitrogen into useful chemicals is embarrassing for the chemical industry, since all the effort of all the industry’s technologists has been unable to find an easy alternative to this.

虽然N2 占我们呼吸的空气3/4 以上，但是氯气不容易用于进一步化学应用。对化学工业来说，N2 的生成有用化学品的生物转化反应难以实现，因为所有的工业技术人员的努力（或尝试）还没有找到该过程的简单其他方法。

Leguminous plants can take nitrogen from the air and convert it into ammonia and ammonium-containing products at atmospheric pressure and ambient temperature; despite a hundred years of effort, the chemical industry still needs high temperatures and pressures of hundreds of atmospheres to do the same job.

在常压和室温条件下，豆类植物能从空气中吸入N2 将之转化为NH3 以及含NH4-的产物。尽管（化学工艺师）花了一百年的精力，要实现上述转化，化学工业仍然需要高温和上百个大气压的压力。

Indeed, until the invention of the Haber process, all nitrogen-containing chemicals came from mineral sources ultimately derived from biological activity.

事实上，直到Haber 过程的发明，所有的含N 化学品都来自于有生物活性的矿物资源。

In principle the reaction between hydrogen and nitrogen is easy; it is exothermic and the equilibrium lies to the right at low temperatures, Unfortunately, nature has bestowed dinitrogen with an inconveniently strong triple bond, enabling the molecule to thumb its nose at thermodynamics.

原则上，H2 和N2 间的反应很容易进行，该反应是放热反应，低温时平衡向右移动。所不幸的是，自然界赋予的N2 一个很强的叁键，这使得N2 分子不易受热力学因素的影响。

In scientific terms the molecule is kinetically inert, and rather severe reaction conditions are necessary to get reactions to proceed at a respectable rate. A major source of “fixed” (meaning, paradoxically, “usefully reactive”) nitrogen in nature is lightning, where the intense heat is sufficient to create nitrogen oxides from nitrogen and oxygen.

用科学术语来说，该分子是动力学惰性的。因此，要使该反应以一定的速度进行，需要相当苛刻的反应条件。实际上，“固定”（意思相互矛盾，“有用的反应活性”）氦的一种主要来源是闪电过程，闪电时生产大量的热量，把N2 和O2转化为N2O。

To get a respectable yield of ammonia in a chemical plant we need to use a catalyst. What Haber discovered-and it won him a Nobel prize was that some iron compounds were acceptable catalysts. Even with such catalysts extreme pressures (up to 600 atmospheres in early processes) and temperatures (perhaps 400C) are necessary.

在化工厂中要得到可观的NH3 的转化率，我们有必要使用催化剂。Haber 发现的催化剂（这使他获得诺贝尔奖）。是一些价廉的含铁的化合物。即使有该催化剂，这反应也需要很高压力（早期高达600个大气压）和高温（大约400C）。

Pressure drives the equilibrium forward, as four molecules of gas are being transformed into two. Higher temperatures, however, drive the equilibrium the wrong way, though they do make the reaction faster chosen conditions must be a compromise that gives an acceptable conversion at a reasonable speed.

因为四个气体分子转化为两个气体分子，所以增加压力使平衡向右（正方向）移动。然而，尽管高温使反应速度加快，但是高温使平衡向右移动，因此，所选的条件必须要折中的能以合理的速率得到令人满意的转化率。

The precise choice will depend on other economic factors and the details of the catalyst. Modern plants have tended to operate at lower pressures and higher temperatures (recycling unconverted material) than the nearer-ideal early plants, since the capital and energy costs have become more significant.

条件的准确选择将取决于其他的经济因素和催化剂的具体情况。因为资本和能耗费用越发重要，当代的工厂已经趋向于比早期工厂在更低的压力和更高的温度（循环使用未转化的物料）下进行操作。

Biological fixation also uses a catalyst which contains molybdenum (or vanadium) and iron embedded in a very large protein, the detailed structure of which eluded chemists until late 1992. How it works is still not understood in detail.

氮的生物固定也使用了一种催化剂，该催化剂镶在较大的蛋白质分子中含有钼和铁，其详细结构直到1992 年才被化学家弄清楚，该催化剂的详细作用机理尚未清楚。

UNIT10

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.

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。

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.

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。

Chemical engineering encompasses the chemical processing of raw materials, based on chemical and physico-chemical phenomena of high complexity.

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。

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”.

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。然而这样做的时候，它并不是仅仅简单地照搬结论，而是要把这些知识运用于大批量生产的化学加工过程。把化学工程学与纯化学区分开来的首要目的是“找到最经济的生产路线并设计商业化的设备和辅助设备尽可能地适应它。”

Therefore, chemical engineering is inconceivable without close ties with economics, physics, mathematics, cybernetics, applied mechanics, and other technical sciences.

因此如果没有与经济学，物理学，数学，控制论，应用机械以及其它技术的联系就不能想象化学工程会是什么样的。

In its early days, chemical engineering was largely a descriptive science. Many of the early textbooks and manuals on chemical engineering were encyclopedias of the commercial production processes known at the time.

早期的化学工程学以描述性为主。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。

Progress in science and industry has bought with it an impressive increase in the number of chemical manufactures. Today, petroleum for example serves as the source material for the production of about 80 thousand chemicals.

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。

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。

UNIT11

Before committing a great deal of time and effort to the study of a subject, it is reasonable to ask the following two questions; what is it? What is it good for? Regarding thermodynamics, the second question is more easily answered, but an answer to the first is essential to an understanding of the subject.

在投入大量的时间和精力去研究一个学科时，有理由去问一下以下两个问题：该学科是什么？（研究）它有何用途？关于热力学，虽然第二个问题更容易回答，但回答第一个问题有必要对该学科较深入的理解。

Although it is doubtful that many experts or scholars would agree on a simple and precise definition of thermodynamics, necessity demands that a definition be attempted. However, this is best accomplished after the applications of thermodynamics have been discussed.

尽管许多专家或学者赞同热力学的简单而准确的定义的观点（看法）值得怀疑，但是还是有必要确定它的定义。然而，在讨论热力学的应用之后，就可以很容易完成其定义。

There are two major applications of thermodynamics, both of which are important to chemical engineers:

热力学有两个主要的应用，两者对化学工程师都很重要。

i) The calculation of heat and work effects associated with processes as well as the calculation of the maximum work obtainable from a process or the minimum work required to drive a process.

1）与过程相联系的热效应和功效应的计算，以及从过程得到的最大功或驱动过程所需的最小功的计算。

ii) The establishment of relationships among the variables describing systems at equilibrium.

2）描述处于平衡的系统的各变量之间的关系的确定。

The first application is suggested by the name thermodynamics, which implies heat in motion. Most of these calculations can be made by the direct implementation of the first and second laws. Examples are calculating the work of compressing a gas, performing an energy balance on an entire process or a process unit, determining the minimum work of separating a mixture of ethanol and water, or evaluating the efficiency of an ammonia synthesis plant.

第一种应用由热力学这个名词可联想到，热力学表示运动中的热。直接利用第一和第二定律可完成许多（热效应和功效应的）计算。例如：计算压缩气体的功，对一个完整过程或某一过程单元的进行能量衡算，确定分离乙醇和水混合物所需的最小功，或者（evaluate）评估一个氨合成工厂的效率。

The application of thermodynamics to a particular system results in the definition of useful properties and the establishment of a network of relationships among the properties and other variables such as pressure, temperature, volume, and mol fraction.

热力学在特殊体系中的应用，引出了一些有用的函数的定义以及这些函数和其它变量（如压强、温度、体积和摩尔分数）关系网络的确定。

Actually, application 1 would not be possible unless a means existed for evaluating the necessary thermodynamic property changes required in implementing the first and second laws. The property changes are calculated from experimentally determined data via the established network of relationships.

实际上，在运用第一、第二定律时，除非用于评价必要的热力学函数变化已经存在，否则热力学的第一种应用不可能实现。通过已经建立的关系网络，从实验确定的数据可以计算函数变化。

Additionally, the network of relationships among the variables of a system allows the calculation of values of variables which are either unknown or difficult to determine experimentally from variables which are either available or easier to measure.

除此之外，某一体系中变量的关系网络，可让那些未知的或者那些难以从变量（这些变量容易得到或较易测量）中实验确定的变量得以计算。

F or example, the hate of vaporizing a liquid can be calculated from measurements of the vapor pressure at several temperatures and the densities of the liquid and vapor phases at severs temperature , and the maximum conversion obtainable in a chemical reaction at any temperature can be calculate from calorimetric measurements performed on the individual substances participating in the reaction.

例如，一种液体的汽化热，可以通过测量几个温度的蒸汽压和几个温度下液相和汽相的密度得以计算；某一化学反应中任一温度下的可得的最大转化率，可以通过参与该反应的各物质的热量法测量加以计算。

UNIT12

Transport phenomena is the collective name given to the systematic and integrated study of three classical areas of engineering science: (i) energy or heat transport, (ii) mass transport or diffusion, and (iii) momentum transport or fluid dynamics.

传递现象是工程科学三个典型领域系统性和综合性研究的总称：能量或热量传递，质量传递或扩散，以及动量传递或流体力学。

Of course, heat and mass transport occur frequently in fluids, and for this reason some engineering educators prefer to includes these processes in their treatment of fluid mechanics .

当然，热量和质量传递在流体中经常发生，正因如此，一些工程教育家喜欢把这些过程包含在流体力学的范畴内。

Since transport phenomena also includes heat conduction and diffusion in solids, however, the subject is actually of wider scope than fluid mechanics.

由于传递现象也包括固体中的热传导和扩散，因此，传递现象实际上比流体力学的领域更广。

It is also distinguished from fluid mechanics in that the study of transport phenomena make use of the similarities between the equations used to describe the processes of heat, mass, and momentum transport.

传递现象的研究充分利用描述传热，传质，动量传递过程的方程间的相似性，这也区别于流体力学。

These analogies, as they are usually called, can often be related to similarities in the physical mechanisms whereby the transport takes place.

这些类推(通常被这么叫)常常可以与传递现象发生的物理机制间的相似性关联起来。

As a consequence, an understanding of one transport process can readily lead to an understanding of other processes.

因此，一个传递过程的理解能够容易促使其他过程的理解。

Moreover, if the differential equations and boundary conditions are the same, a solution need be obtained for only one of the processes since by changing the nomenclature that solution can be used to obtain the solution for any other transport process.

而且，如果微分方程和边界条件是一样的，只需获得一个传递过程的解决方案即可，因为通过改变名称就可以用来获得其他任何传递过程的解决方案。

It must be emphasized, however, that while there are similarities between the transport processes, there are also important differences, especially between the transport of momentum (a vector) and that of heat or mass (scalars ).

必须强调,虽然有相似之处,也有传递过程之间的差异,尤其重要的是运输动量(矢量)和热或质量(标量).

Nevertheless, a systematic study of the similarities between the transport processes makes it easier to identify and understand the differences between them.

然而,系统地研究了相似性传递过程之间的相似性,使它更容易识别和理解它们之间的差别。

In order to demonstrate the analogies between the transport processes, we will study each of the process in parallel-instead of studying momentum transport first , then energy transport , and finally mass transport.

为了找出传递过程间的相似性，我们将同时研究每一种传递过程——取代先研究动量传递，再传热，最后传质的方法。

Besides promoting understanding, there is another pedagogical reason for not using the serial approach that is used in other textbooks: of the three processes, the concepts and equations involved in the study of momentum transport are the most difficult for the beginner to understand and to use.

除了促进理解之外，对于不使用在其他教科书里用到的顺序法还有另一个教学的原因：在三个过程中，包含在动量传递研究中的概念和方程对初学者来说是最难以理解并使用。

Because it is impossible to cover heat and mass transport thoroughly without prior knowledge of momentum transport, one is forced under the serial approach to take up the most difficult subject (momentum transport) first.

因为在不具有有关动量传递的知识前提下一个人不可能完全理解传热和传质，在顺序法的情况下他就被迫先研究最难的课程即动量传递。

On the other hand, if the subjects are studied in parallel, momentum transport becomes more understandable by reference to the familiar subject of heat transport.

另一方面，如果课程同时被研究，通过参照有关传热的熟悉课程动量传递就变得更好理解。

Furthermore, the parallel treatment makes it possible to study the simpler the physical processes that are occurring rather than the mathematical procedures and representations.

而且，平行研究法可以先研究较为简单的概念，再深入到较难和较抽象的概念。我们可以先强调所发生的物理过程而不是数学性步骤和描述。

For example ，we will study one-dimensional transport phenomena first because equations instead of partial requiring vector notation and we can often use ordinary differential equations

instead of partial differential equations ,which are harder to solve .

例如，我们将先研究一维传递现象，因为它在不要求矢量标注下就可以被解决，并且我们常常可以使用普通的微分方程代替难以解决的偏微分方程。

This procedure is also justified by the fact that many of the practical problems of transport phenomena can be solved by one-dimensional models.

加上传递现象的许多实际问题可以通过一维模型解决的这样一个事实，这种处理做法也是合理的。