专业英语课文翻译

United 1 材料科学与工程

材料在我们的文化中比我们认识到的还要根深蒂固。如交通、房子、衣物，通讯、娱乐和食物的生产，实际上，我们日常生活中的每一部分都或多或少地受到材料的影响。历史上社会的发展、先进与那些能满足社会需要的材料的生产及操作能力密切相关。实际上，早期的文明就以材料的发展程度来命名，如石器时代，铜器时代。早期人们能得到的只有一些很有限的天然材料，如石头、木材、粘土等。渐渐地，他们通过技术来生产优于自然材料的新材料，这些新材料包括陶器和金属。进一步地，人们发现材料的性质可以通过加热或加入其他物质来改变。在这点上，材料的应用完全是一个选择的过程。也就是说，在一系列非常有限的材料中，根据材料的优点选择一种最适合某种应用的材料。直到最近，科学家才终于了解材料的结构要素与其特性之间的关系。这个大约是过去的 60 年中获得的认识使得材料的性质研究成为时髦。因此，成千上万的材料通过其特殊的性质得以发展来满足我们现代及复杂的社会需要。很多使我们生活舒适的技术的发展与适宜材料的获得密切相关。一种材料的先进程度通常是一种技术进步的先兆。比如，没有便宜的钢制品或其他替代品就没有汽车。在现代，复杂的电子器件取决于所谓的半导体零件.

材料科学与工程有时把材料科学与工程细分成材料科学和材料工程学科是有用的。严格地说，材料科学涉及材料到研究材料的结构和性质的关系。相反，材料工程是根据材料的结构和性质的关系来设计或操纵材料的结构以求制造出一系列可预定的性质。从功能方面来说，材料科学家的作用是发展或合成新的材料，而材料工程师是利用已有的材料创造新的产品或体系，和/或发展材料加工新技术。多数材料专业的本科毕业生被同时训练成材料科学家和材料工程师。“structure”一词是个模糊的术语值得解释。简单地说，材料的结构通常与其内在成分的排列有关。原子内的结构包括介于单个原子间的电子和原子核的相互作用。在原子水平上，结构包括原子或分子与其他相关的原子或分子的组织。在更大的结构领域上，其包括大的原子团，这些原子团通常聚集在一起，称为“微观”结构，意思是可以使用某种显微镜直接观察得到的结构。最后，结构单元可以通过肉眼看到的称为宏观结构。

“Property”一词的概念值得详细阐述。在使用中，所有材料对外部的刺激都表现出某种反应。比如，材料受到力作用会引起形变，或者抛光金属表面会反射光。材料的特征取决于其对外部刺激的反应程度。通常，材料的性质与其形状及大小无关。实际上，所有固体材料的重要性质可以概括分为六类：机械、电学、热学、磁学、光学和腐蚀性。对于每一种性质，其都有一种对特定刺激引起反应的能

力。如机械性能与施加压力引起的形变有关，包括弹性和强度。对于电性能，如电导性和介电系数，特定的刺激物是电场。固体的热学行为则可用热容和热导率来表示。磁学性质

表示一种材料对施加的电场的感应能力。对于光学性质，刺激物是电磁或光照。用折射和反射来表示光学性质。最后，腐蚀性质表示材料的化学反应能力。除了结构和性质，材料科学和工程还有其他两个重要的组成部分，即加工和性能。如果考虑这四个要素的关系，材料的结构取决于其如何加工。另外，材料的性能是其性质的功能。因此，材料的加工、结构、性质和功能的关系可以用以下线性关系来表示：加工——结构——性质——性能。为什么研究材料科学与工程？为什么研究材料科学与工程？许多应用科学家或工程师，不管他们是机械的、民事的、化学的或电子的领域的，都将在某个时候面临材料的设计问题。如用具的运输、建筑的超级结构、油的精炼成分、或集成电路芯片。当然，材料科学家和工程师是从事材料研究和设计的专家。

很多时候，材料的问题就是从上千个材料中选择出一个合适的材料。对材料的最终选择有几个原则。首先，现场工作条件必须进行表征。只有在少数情况下材料在具有最优或理想的综合性质。因此，有必要对材料的性质进行平衡。典型的例子是当考虑材料的强度和延展性时，而通常材料具有高强度但却具有低的延展性。这时对这两种性质进行折中考虑很有必要。其次，选择的原则是要考虑材料的性质在使用中的磨损问题。如材料的机械性能在高温或腐蚀环境中会下降。最后，也许是最重要的原则是经济问题。最终产品的成本是多少？一种材料的可以有多种理想的优越性质，但不能太昂贵。这里对材料的价格进行折中选择也是可以的。产品的成本还包括组装中的费用。工程师与科学家越熟悉材料的各种性质、结构、功能之间的关系以及材料的加工技术，根据以上的几个原则，他或她对材料的明智选择将越来越熟练和精确。

Unit 2 Classification of Materials

Solid materials have been conveniently grouped into three basic

classifications: metals, ceramics, and polymers. This scheme is based

primarily on chemical makeup and atomic structure, and most materials fall into one distinct grou ping or another, although there are some intermediates. In addition, there are three other groups of important engineering materials—composites, semiconductors, and biomaterials.

译文：固体材料被便利的分为三个基本的类型：金属，陶瓷和聚合物。这个分类是首先基于化学组成和原子结构来分的，大多数材料落在明显的一个类别里面，尽管有许多中间品。除此之外，有三类其他重要的工程材料－复合材料，半导体材料和生物材料。

Composites consist of combinations of two or more different materials, whereas semiconductors a re utilized because of their unusual electrical characteristics; biomaterials are implanted into the h uman body. A brief explanation of the material types and representative characteristics is offered n ext.

译文：复合材料由两种或者两种以上不同的材料组成，然而半导体由于它们非同寻常的电学性质而得到使用；生物材料被移植进入人类的身体中。关于材料类型和他们特殊的特征的一个简单的解释将在后面给出。 METALS

Metallic materials are normally combinations of metallic elements. They have large numbers of no nlocalized electrons; that is, these electrons are not bound to particular atoms. Many properties of metals are directly able to these electrons.

be bound to 被约束于。be attribute to 归属于。。归因于。。

译文：金属材料通常由金属元素组成。它们有大量无规则运动的电子。也就是说，这些电子

不是被约束于某个特定的原子。金属的许多性质直接归属这些不规则运动的电子。

Metals are extremely good conductors of electricity and heat and are not transparent to visible ligh t; a polished metal surface has a lustrous

appearance. Furthermore, metals are quite strong, yet deformable, which accounts for their extensi ve use in structural applications.

科技英语在讲述科学真理的时候通常用主动语态。如： Metals are extremely good conductors of electricity Deformable ？

译文：金属是十分好的电和热的导体，它们对可见光不透明；一个抛光的金属表面有光辉的外表。除此之外，金属是十分硬的，也是可变

形的，这个性质解释了它们广泛使用在结构方面的应用。 CERAMICS

Ceramics are compounds between metallic and nonmetallic elements; they are most frequently oxi des, nitrides, and carbides. The wide range of materials that falls within this classification includes ceramics that are composed of clay minerals, cement, and glass. that引导的定语从句

译文：陶瓷是介于金属和非金属元素之间的化合物；它们通常是氧化物，氮化物和碳化物。落在这个分类种类中的宽的材料范围包括陶瓷，它们由粘土矿物，水泥和玻璃组成。These materials are typically insulative to the passage of electricity and heat, and are more resistan t to high temperatures and harsh environments than metals and polymers. With regard to mechanic al behavior, ceramics are hard but very brittle. more…. Than….. with regard to….

译文：这些材料是典型的电和热的绝缘体，并且它们比金属和聚合物更加耐高温和耐苛刻的环境。至于机械性能，陶瓷是硬的但是却很脆。

POL YMERS

Polymers include the familiar plastic and rubber materials. Many of them are organic compounds t hat are chemically based on carbon, hydrogen, and other nonmetallic elements; furthermore, they have very large molecular structures. These materials typically have low densities and may be extr emely flexible.

译文：聚合物包括常见的塑料和橡胶材料。它们中的大多数是有机化合物，这些化合物是以化学的方法把碳、氢和其他非金属元素组合而成。因此，它们有非常大的分子结构。这些材料通常有低的密度并且可能十分柔软。 COMPOSITES

A number of composite materials have been engineered that consist of more than one material typ e. Fiberglass is a familiar example, in which glass fibers are embedded within a polymeric materi al. more than…

译文：许多复合材料被作用工程使用，它们由至少一种类型的材料组成。玻璃丝是一个熟悉的例子，玻璃纤维被埋入聚合物材料中。

A composite is designed to display a combination of the best characteristics of each of the compon ent materials. Fiberglass acquires strength from the glass and flexibility from the polymer. Many o

f the recent material developments have involved composite materials.

译文：为了联合显示每一种组分材料最好的特性，一种复合材料被设计出来。玻璃丝从玻璃中获得强度并且从聚合物中获得柔软性。最近发展中的绝大多数材料包含了复合材料。 SEMICONDUCTORS

Semiconductors have electrical properties that are intermediate between the electrical conductors a nd insulators. Furthermore, the electrical

characteristics of these materials are extremely sensitive to the presence of minute concentrations of impurity atoms, which concentrations may be controlled over very small spatial regions. be sen sitive to 对…敏感的

译文：半导体有电的性质，它们是介于电导体和绝缘体之间的中间物。除此之外，这些材料的电学性质对微量杂质原子的存在十分敏感，杂质原子浓度可能只是在一个十分小的区域内可以控制。 The semiconductors have made possible the advent of integrated circuitry that has totally rev olutionized the electronics and computer industries (not to mention our lives) over the past two de cades.

译文：这些半导体使得集成电路的出现变得可能，在过去20多年间，这些集成电路革新了电子装置和计算机工业（更不用说我们的生活）。

BIOMA TERIALS

Biomaterials are employed in components implanted into the human

body for replacement of diseased or damaged body parts. These materials must not produce toxic s ubstances and must be compatible with body tissues (i.e., must not cause adverse biological reacti ons).

译文：生物材料被应用于移植进入人类身体以取代病变的或者损坏的身体部件。这些材料不能产生有毒物质而且必须同人身体器官要相容（比如，不能导致相反的生物反应）。

All of the above materials—metals, ceramics, polymers,

composites, and semiconductors—may be used as biomaterials. For

example, some of the biomaterials such as CF/C (carbon fibers/carbon) and CF/PS (polysulfone) are utilized in artificial hip replacements.

译文：所有以上材料－金属，陶瓷，聚合物，复合材料和半导体材料可能用作生物材料。比如，如CF/C和CF/PS（聚砜）这些生物材料被用作人工肾的取代物。

ADV ANCED MA TERIALS

Materials that are utilized in high-technology (or high-tech) applications are sometimes termed ad vanced materials. By high technology we mean a device or product that operates or functions usin g relatively intricate and sophisticated principles; examples include electronic equipment (VCRs, CD players, etc.), computers, fiberoptic systems, spacecraft, aircraft, and military rocketry.

译文：用在高科技中的材料有时被称作先进材料。借助于高科技，我们预定一个装置或者产品，这些产品用相对复杂和熟练的原理运转或者起作用；这些例子包括电子设备（ VCRs, CD 播放器），计算机，光纤系统，宇宙飞船，航天飞机和军事火箭。

These advanced materials are typically either traditional materials whose properties have been enh anced or newly developed, high-performance materials. Furthermore, they may be of all material t ypes (e.g., metals, ceramics, polymers), and are normally relatively expensive.

译文：这些高级材料或是典型的传统材料，它们的性质被提高，最近开发出来的，高性能材料。除此之外，它们可能是所有材料类型（比如，金属、陶瓷和聚合物），通常相对较贵。In subsequent chapters are discussed the properties and applications of a number of advanced mate rials—for example, materials that are used for lasers, integrated circuits, magnetic information storage, li quid crystal displays (LCDs),

fiber optics, and the thermal protection system for the Space Shuttle Orbiter. 译文：在下面的章节将讨论众多先进材料的性质和应用－比如被用作激光，集成电路，磁信息存储，液晶显示器，光纤和空间舱轨道的热保护系统的材料。

MODERN MATERIALS’ NEEDS

In spite of the tremendous progress that has been made in the discipline of materials science and e ngineering within the past few years, there still remain technological challenges, including the dev elopment of even more sophisticated and specialized materials, as well as consideration of the environmental impact of materials production. Some comment is appropriate relative to these issu es so as to round out this perspective.

译文：在过去几年内，不论材料科学与工程的规律取得了巨大的进步，仍然有一些技术挑战，包括开发更加熟练的专业化的材料，并且考虑材料生产对环境导致的影响。针对这个问题，一些评论是十分相关的。

Nuclear energy holds some promise, but the solutions to the many problems that remain will neces sarily involve materials, from fuels to containment structures to facilities for the disposal of radio active waste.

译文：核能还保持着一些承诺，但是解决许多仍然存在的问题，将有必要把材料包括在里，从燃料到保护结构以便方便处置这些放射性废料。

Significant quantities of energy are involved in transportation. Reducing the weight of transportati on vehicles (automobiles, aircraft, trains, etc.), as well as increasing engine operating temperatures , will enhance fuel efficiency. New high strength,low-density structural materials remain to be dev eloped, as well as materials that have higher-temperature capabilities, for use in engine component s.

译文：相当数量的能源用在交通上。减少交通工具（汽车，飞机，火车等）的重量，和提高引擎操作温度，将提高燃料的使用效率。新的

高强，低密度结构材料仍在发展，用作引擎部位能耐高温材料也在发展中。Furthermore, there is a recognized need to find new, economical sources of energy, and to use the present resources more efficiently. Materials will undoubtedly play a significant role in these deve lopments.

译文：除此之外，寻找新的、经济的能源资源，并且更加有效的使用目前现存的资源是公认为必须的。材料将毫无疑问的在这些发展过程中扮演重要的角色。

For example, the direct conversion of solar into electrical energy has been demonstrated. Solar cell s employ some rather complex and expensive

materials. To ensure a viable technology, materials that are highly efficient in this conversion proc ess yet less costly must be developed.

译文：比如，太阳能直接转化为电能已经被证实了。太阳能电池使用相当复杂并且昂贵的材料。为了保证技术的可行，在这个转化过程中的高效但不贵的材料必须被发展。Furthermore, environmental quality depends on our ability to control air and water pollution. Pollu tion control techniques employ various materials. In addition, materials processing and refinement methods need to be

improved so that they produce less environmental degradation, that is, less pollution and less desp oilage of the landscape from the mining of raw materials.

译文：除此之外，环境质量取决于我们控制大气和水污染的能力。污染控制技术使用了各种材料。再者，材料加工和精制的方法需要改善以便它们产生很少的环境退化，也就是说，在生材料加工过程中，带来更少的污染和更少的对自然环境的破坏。

Also, in some materials manufacturing processes, toxic substances are produced, and the ecologic al impact of their disposal must be considered. Many materials that we use are derived from resour ces that are nonrenewable, that is, not capable of being regenerated.

These include polymers, for which the prime raw material is oil, and some metals. These nonrene wable resources are gradually becoming depleted. 译文：也，在一些材料生产过程中，有毒物质产生了，并且它们的处置对生态产生的影响必须加以考虑。我们使用的许多材料来源于不可再生的资源，不可再生也就是说不能再次生成的。这些材料包括聚合物，最初的原生材料是油和一些金属。这些不可再生的资源逐渐变得枯竭

which necessitates: 1) the discovery of additional reserves, 2) the development of new materials h aving comparable properties with less

adverse environmental impact, and/or 3) increased recycling efforts and the

development of new recycling technologies.

译文：下面是必须的：1）发现另外的储藏，2）开发拥有较少负环境影响的新材料，3)增加循环的努力并且开发新的循环技术。 As a consequence of the economics of not only production but also

environmental impact and ecological factors, it is becoming increasingly important to consider the ‘‘cradle-to-grave’’ life cycle of materials relative to the overall manufacturing process.

译文：结果，不仅是生产，而且环境影响和生态因子，和材料整个生产过程紧密相关的材料“一生”的生命周期的考虑变得越来越重要。

The word "ceramic" is derived from the Greek keramos, which means "potter's clay" or "pottery." Its origin is a Sanskrit term meaning "to burn." So the early Greeks used "keramous" when descri bing products obtained by heating clay-containing materials. The term has long included all produ cts made from fired clay, for example, bricks, fireclay refractories, sanitaryware, and tableware. “陶瓷”这个词是来自希腊keramos，这意味着“陶土”或“陶”。它的起源是梵文术语，意思是“燃烧”。因此，早期的希腊人用“keramous”描述加热含粘土的物料获得的产品。这个词早已包括所有陶土制成的产品，例如，砖，粘土质耐火材料，卫生洁具，餐具。

In 1822, refractory silica were first made. Although they contained no clay, the traditional ceramic process of shaping, drying, and firing was used to make them. So the term" ceramic," while retaini ng its original sense of a product made from clay, began to include other products made by the sa me manufacturing process. The field of ceramics (broader than the materials themselves) can be d efined as the art and science of making and using solid articles that contain as their essential comp onent a ceramic. This definition covers the purification of raw materials, the study and production of the chemical compounds concerned, their formation into components, and the study of structure , composition, and properties.

1822年，耐火材料二氧化硅被首次提出。虽然他们中没有粘土，传统陶瓷的塑造过程，干燥和烧成使用，使它们。所以说，“陶瓷”，同时保留其原来意义上的粘土制成的产品，开始向包括由同一制造工艺制成的其他产品。陶瓷比材料本身更广泛的领域可以被定义为制作和使用含有固体的文章作为自己的重要组成部分陶瓷艺术和科学。这个定义涵盖了原料的净化，研究和生产有关的化学成分，他们到组件的形成，结构，组成和性质的研究。Ceramics are usually associated with "mixed" bonding-a combination of covalent, ionic, and some times metallic. They consist of arrays of

interconnected atoms; there are no discrete molecules. This characteristic distinguishes ceramics fr om molecular solids such as iodine crystals

(composed of discrete I2 molecules) and paraffin wax (composed of long-chain alkane molecules). It also excludes ice, which is composed of discrete H20 molecules and often behaves just like ma ny ceramics. The majority of ceramics are compounds of metals or metalloids and nonmetals. Mos

t frequently they are oxides, nitrides, and carbides.

陶瓷通常与“混合”接合的共价键，离子，有时金属结合。他们组成的相互联系的原子阵列;没有离散的分子。这一特点区分，如碘晶体（离散碘分子组成）和石蜡（长链烷烃分子组成）分子固体的陶瓷。它也排除了冰，这是由离散的水分子，往往表现就像许多陶瓷。大多数陶瓷，金属或非金属化合物和非金属。他们最常见的氧化物，氮化物和碳化物。

However, diamond and graphite are also classified as ceramics. These forms of carbon are inorgan ic in the most basic meaning of the term: they were not prepared from the living organism.

然而，金刚石和石墨也被归类为陶瓷。这些形式的碳是无机一词的最基本的含义：他们不准备从活的有机体。

General Properties一般属性

Ceramics generally have specific properties associated with them. We will look at some properties and see how closely they match our expectations of what constitutes a ceramic.

陶瓷一般都与他们相关的特定属性。我们将看看一些属性，看看他们如何紧密匹配何谓陶瓷我们的期望。

Brittleness脆性 This probably comes from personal experiences such as dropping a glass beaker or a dinner_ plate. The reason that the majority of ceramics are brittle is the mixed ionic-covalent bonding that holds the

constituent atoms together. At high temperatures (above the glass transition temperature), glass no longer behaves in a brittle manner; it behaves as a viscous liquid. That is why it is easy to form gla ss into intricate shapes. So what we can say is that most ceramics are brittle at room temperature b ut not necessarily at elevated temperatures.

这可能来自于个人的经验，如删除一个玻璃烧杯或餐盘。大多数陶瓷是易碎的原因是共同持有的组成原子的混合离子共价键。在高温（玻璃化转变温度以上），玻璃不再表现脆性的方式，它作为一种粘性液体的行为。这就是为什么它很容易形成复杂形状的玻璃。因此，我们可以说是大多数陶瓷在室温下很脆，但在高温下不一定。

Poor electrical and thermal conduction恶劣的电气和热传导 The valence electrons are tied up in bonds, and are not free as they are in metals. In metals it i s the free electrons-the electron gas-that determines many of their electrical and thermal properties . Diamond, which is classified as a ceramic, has the highest thermal conductivity of any known m aterial. The conduction mechanism is due to Phonons, not electrons. Ceramics can also have high electrical conductivity,(1)the oxide ceramic, ReO3, has an electrical conductivity at room tempera ture similar to that of Cu; (2) the mixed oxide YBa2Cu3O7 is an HTSC; it has zero resistivity be low 92K. 价电子被捆绑起来的债券，是不是免费的，因为他们在金属。在金属，它是自由电

子的电子气，决定其电气和热性能。钻石，这是作为陶瓷的分类，有任何已知的材料的导热系数最高。传导机制是由于声子，没有电子。陶瓷也可以有高导电性，（1）氧化物陶瓷，ReO3，有一个类似的铜在室温下的电导率;（2）混合氧化物YBa2Cu3O7是高温超导;它具有零电阻低于92K。

These are two examples that contradict the conventional wisdom when it comes to ceramics.

这些都违背了传统的智慧，当谈到陶瓷的两个例子。

Compressive strength抗压强度 Ceramics are stronger in compression than in tension, whereas metals have comparable tensile and compressive strengths. This difference is important when we use ceramic components for loa d-bearing applications. It is necessary to consider the stress distributions in the ceramic to ensure t hat they are compressive. An important example is in the design of concrete bridges-the concrete, a CMC, must be kept in compression. Ceramics generally have low toughness, although combinin g them in composites can dramatically improve this property.

陶瓷在紧张的压缩比，而金属具有可比性的抗拉和抗压强度。这种差异是很重要的，当我们使用承载应用的陶瓷元件。这是有必要考虑在陶瓷的应力分布，以确保它们是压缩。一个重要的例子是在设计的混凝土桥梁，混凝土，中央军委，必须保持在压缩。陶瓷一般有韧性低，虽然复合材料相结合，可以极大地提高这个属性。

Chemical insensitivity 化学不灵敏度 A large number of ceramics are stable in both harsh chemical and thermal environments. Pyrex glass is used widely in chemistry laboratories specifically be-cause it is resistant to many corrosiv e chemicals, stable at high temperatures (it does not soften until 1100K), and is resistant to thermal shock because of its low coefficient of thermal expansion (33×10-7K-1). It is also widely used in bakeware.

大量的陶瓷，在苛刻的化学和热环境是稳定的。硼硅玻璃是在化学实验室中广泛使用，具体原因是抵抗许多腐蚀性化学品的，稳定的高温（不软化，直到1100K），抵抗热冲击，由于其低的热膨胀系数（33×10- 7K- 1）。它也被广泛用于在烤盘。

Transparent透明 Many ceramics are transparent because they have a large Eg. Examples include sapphire watc h covers, precious stones, and optical fibers. Glass optical fibers have a percent transmission >96 %km-1. Metals are transparent to visible light only when they are very thin, typically less than 0.1μm.

许多陶瓷是透明的，因为他们有一个大的如。例子包括蓝宝石手表盖，宝石，和光纤。玻璃光纤具有传输％>96％每公里。金属可见光是透明的的，只有当他们是非常薄，通常小于0.1微米。

Although it is always possible to find at least one ceramic that shows a typical behavior, the prope rties mentioned above are in many cases different from those shown by metals and polymers.

虽然它总是可以找到至少一个陶瓷，显示了一个典型的行为，上面提到的属性不同的金属和聚合物中的许多案件。

Types of Ceramic and Their Applications陶瓷及其应用的类型 Large numbers of materials are ceramics. The applications for these materials are diverse, from bricks and tiles to electronic and magnetic components. These applications use the wide range of properties exhibited by ceramics. Some of these properties are listed in Table 3.1 together with ex amples of specific ceramics and applications. The functions of ceramic products are dependent on their chemical composition and microstructure, which determines their properties. It is the interrel ationship between structure and properties that is a key element of materials science and engineeri ng.

大量的材料是陶瓷。这些材料的应用是多种多样的，从砖瓦，电子和磁性元件。这些应用程序使用广泛的陶瓷展出的属性。这些属性与特定的陶瓷和应用的例子，在表3.1列出了一些。陶瓷产品的功能上取决于其化学成分和微观结构，这就决定了它们的属性。它的结构和性能的关键因素是材料科学与工程之间的相互关系。

You may find that, in addition to dividing ceramics according to their properties and applications, i t is common to class them as traditional or advanced. Traditional ceramics include high-volume ite ms such bricks and tiles, toilet bowls (whitewares), and pottery. Advanced ceramics include newer materials such as laser host materials, piezoelectric

ceramics .ceramics for dynamic random access memories (DRAMs), and so on, often produced in small quantities with higher prices. There are other characteristics that separate these categories. 您可能会发现，除了除以陶瓷根据其性质和应用，它是常见他们为传统或先进的阶级。传统的陶瓷，包括高容量的项目，如砖瓦，马桶（whitewares），和陶器。先进陶瓷新材料，如激光基质材料，压电陶瓷，陶瓷，动态随机存取存储器（DRAM的）等，往往在价格较高的小批量的生产。有单独的这些类别的其他特点。

Traditional ceramics are usually based on clay and silica. There is sometimes a tendency to equate traditional ceramics with low technology, however, advanced manufacturing techniques are often used. Competition among producers has caused processing to becom1 more efficient and cost effe ctive. Complex tooling and machinery is often used and may be coupled with computer-assisted p rocess control.

通常是基于传统的陶瓷粘土和二氧化硅。然而，有时也有一种倾向等同于低技术传统陶瓷，先进的制造技术通常用于。生产者之间的竞争已经引起处理becom1更有效率和成本效益。

经常使用复杂的工具和机械，并可能与计算机辅助工艺控制。

Advanced ceramics are also referred to as "special", “technical", or “engineering" ceramics. They exhibit superior mechanical properties, corrosion/oxidation resista nce, or electrical, optical, and/or magnetic properties. While traditional clay-based ceramics have been used for over

25000 years, advanced ceramics have generally been developed within the last 100 years.

先进陶瓷也被称为“特殊”，“科技”，或“工程”的陶瓷。他们表现出优越的机械性能，耐腐蚀/抗氧化性能，电，光，和/或磁学性质。虽然已超过25000年的使用传统的粘土基陶瓷，先进陶瓷已普遍被发达国家在过去100年。

Table 3.2 compares traditional and advanced ceramics in terms of the type of raw materials used, t he forming and shaping processes, and the methods used for characterization.

表3.2比较传统和先进的陶瓷，在原材料的使用类型方面的形成和塑造的过程和方法用于表征。

化学专业英语(修订版)翻译

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大学英语精读1课文翻译

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《化学工程与工艺专业英语》课文翻译 完整版

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汽车专业英语翻译

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[实用参考]大学英语精读第三版第四册课文及课文翻译.doc

Unit1 Twocollege-ageboPs,unawarethatmakingmonePusuallPinvolveshardwork,aretemptedbPanadvertis ementthatpromisesthemaneasPwaPtoearnalotofmoneP.TheboPssoonlearnthatifsomethingseemstog oodtobetrue,itprobablPis. 一个大学男孩，不清楚赚钱需要付出艰苦的劳动，被一份许诺轻松赚大钱的广告吸引了。男孩们很快就明白，如果事情看起来好得不像真的，那多半确实不是真的。BIGBUCKSTHEEASPWAP轻轻松松赚大钱"Pououghttolookintothis,"Isuggestedtoourtwocollege-agesons."ItmightbeawaPtoavoidtheindignitP ofhavingtoaskformonePallthetime."Ihandedthemsomemagazinesinaplasticbagsomeonebadhungon ourdoorknob.AmessageprintedonthebagofferedleisurelP,lucrativework("BigBuckstheEasPWaP!")o fdeliveringmoresuchbags. “你们该看看这个，”我向我们的两个读大学的儿子建议道。“你们若想避免因为老是向人讨钱而有失尊严的话，这兴许是一种办法。”我将挂在我们门把手上的、装在一个塑料袋里的几本杂志拿给他们。塑料袋上印着一条信息说，需要招聘人投递这样的袋子，这活儿既轻松又赚钱。（“轻轻松松赚大钱!”） "Idon'tmindtheindignitP,"theolderoneanswered.“我不在乎失不失尊严，”大儿子回答说。"Icanlivewithit,"hisbrotheragreed.“我可以忍受，”他的弟弟附和道。"Butitpainsme,"Isaid，"tofindthatPoubothhavebeenpanhandlingsolongthatitnolongerembarrassesPou."“看到你们俩伸手讨钱讨惯了一点也不感到尴尬的样子，真使我痛心，”我说。TheboPssaidthePwouldlookintothemagazine-deliverPthing.Pleased,Ilefttownonabusinesstrip.BPmi dnightIwascomfortablPsettledinahotelroomfarfromhome.Thephonerang.ItwasmPwife.Shewantedt oknowhowmPdaPhadgone.孩子们说他们可以考虑考虑投递杂志的事。我听了很高兴，便离城出差去了。午夜时分，我已远离家门，在一家旅馆的房间里舒舒服服住了下来。电话铃响了，是妻子打来的。她想知道我这一天过得可好。 "Great!"Ienthused."HowwasPourdaP?"Iinquired.“好极了!”我兴高采烈地说。“你过得怎么样?”我问道。 "Super!"Shesnapped."Justsuper!Andit'sonlPgettingstarted.Anothertruckjustpulledupoutfront."“棒极了!”她大声挖苦道。“真棒!而且这还仅仅是个开始。又一辆卡车刚在门前停下。”"Anothertruck?"“又一辆卡车?” "Thethirdonethisevening.ThefirstdeliveredfourthousandMontgomerPWards.Thesecondbroughtfour thousandSears,Roebucks.Idon'tknowwhatthisonehas,butI'msureitwillbefourthousandofsomething.S incePouareresponsible,IthoughtPoumightliketoknowwhat'shappening.“今晚第三辆了。第一辆运来了四千份蒙哥马利-沃德百货公司的广告；第二辆运来四千份西尔斯-罗伯克百货公司的广告。我不知道这一辆装的啥，但我肯定又是四千份什么的。既然这事是你促成的，我想你或许想了解事情的进展。” WhatIwasbeingblamedfor,itturnedout,wasanewspaperstrikewhichmadeitnecessarPtohand-deliverth eadvertisinginsertsthatnormallPareincludedwiththeSundaPpaper.ThecompanPhadpromisedourboPs $600fordeliveringtheseinsertsto4,000housesbPSundaPmorning.我之所以受到指责，事情原来是这样：由于发生了一起报业工人罢工，通常夹在星期日报纸里的广告插页，必须派人直接投送出去。公司答应给我们的孩子六百美金，任务是将这些广告插页在星期天早晨之前投递到四千户人家去。 "Pieceofcake!"ouroldercollegesonhadshouted.“不费吹灰之力!”我们上大学的大儿子嚷道。"SiGhundredbucks!"Hisbrotherhadechoed,"Andwecandothejobintwohours!"“六百块!”他的弟弟应声道，“我们两个钟点就能干完!” "BoththeSearsandWardadsarefournewspaper-sizepages,"mPwifeinformedme."TherearethirtP-twot housandpagesofadvertisingonourporch.Evenaswespeak,twobigguPsarecarrPingarmloadsofpaperup thewalk.Whatdowedoaboutallthis?"“西尔斯和沃德的广告通常都是报纸那么大的四页，”妻子告诉我说，“现在我们门廊上堆着三万二千页广告。就在我们说话的当儿，两个大个子正各抱着一大捆广告走过来。这么多广告，我们可怎么办?”"JusttelltheboPstogetbusP,"Iinstructed."TheP'recollegemen.TheP'lldowhatthePhavetodo."“你让孩子们快干，”我指示说。“他们都是大学生了。他们自己的事得由他们自己去做。”AtnoonthefollowingdaPIreturnedtothehotelandfoundanurgentmessagetotelephonemPwife.Hervoic

汽车专业英语_单词表

unit1 body 车身chassis 底盘enclosure外壳、套hood车棚、车顶sway 摇摆frame车架steering转向、操作brake 制动weld焊接rivet铆钉bolt螺钉washer垫圈vibration 振动stabilizer稳定器ride乘坐舒适性handling操作稳定性linkages转向传动机构plier钳子distributor分电器alternator交流发电机regulator调节器carburetor化油器radiator散热器、水箱defroster除冰装置sludge金属碎屑transmission变速器differential 差速器power train 传动系unitized body 承载式车身suspension system 悬架系统steering system 转向系braking system 制动系shock absorbers减震器control arms控制臂steering wheel 转向盘steering column转向管柱steering gears 转向器tie rod 横拉杆idler arm随动臂brake shoe制动蹄disc brake 盘式制动器drum brakes 鼓式制动器ignition system 点火系统exhaust system 排气系统lubrication system 润滑系oil filters 机油滤清器drive（or propeller）shaft传动轴universal joints 万向节dynamo发电机horn喇叭swived 旋转steering box转向器timing gear 正时齿轮bevel gear 锥齿轮mesh with与啮合leaf spring 钢板弹簧stub axle 转向节 unit2 longitudinal纵向的transverse横向的reciprocate往复spin旋转piston活塞ignite点火rub摩擦quart夸脱reservoir油箱mechanical机械的enclosed被附上的gallon加仑stroke冲程camshaft凸轮轴combustion燃烧disengaged脱离啮合的flywheel飞轮internal-combustion engine内燃机diesel-fuel柴油LPG=Liquefied Petroleum Gas液化石油气体CNG=Compressed natural gas压缩天然气spark ignition火花点火compression ignition压缩点火spark plug火花塞gas-turbine engine蒸汽机Stirling engine斯特灵发动机lubricating system润滑系统oil pan油底壳oil pump机油泵exhaust system排气系统emission-control system排放控制系统energy conversion能量转换air/fuel ratio空燃比connecting rod连杆TDC=Top Dead Center上止点BDC=Bottom Dead Center 下止点intake stroke进气冲程compression stroke压缩冲程power stroke作功冲程exhaust stroke排气冲程compression ratio压缩比lifter挺柱rocker摇臂retainer弹簧座seal密封件tappet 推杆lobe凸起gasket垫圈valve train配气机构cam follower气门挺柱rocker arm摇臂combustion chamber燃烧室intake valve进气阀exhaust valve排气阀valve stem气门杆valve cover气门室盖valve port阀口valve guide气门导管 unit3

大学英语精读课文翻译

大学英语精读课文翻译 Unit 1 How to Improve Your Study Habits 你也许是个智力一般的普通学生。你在学校的学习成绩还不错，可你也许会觉得自己永远也成不了优等生。然而实际情况未必如此。你要是想取得更好的分数，也还是能做到的。是的，即使中等智力水平的学生，在不增加学习负担的情况下，也能成为优等生。其诀窍如下：1．仔细安排你的时间。把你每周要完成的任务一一列出来，然后制定一张时间表或时间分配图。先把用于吃饭、睡觉、开会、听课等这样一些非花不可的时间填上，然后再选定合适的固定时间用于学习。一定要留出足够的时间来完成正常的阅读和课外作业。当然，学习不应把作息表上的空余时间全都占去，还得给休息、业余爱好和娱乐活动留出一定的时间，这一点很重要。这张周作息表也许解决不了你所有的问题，但是它会使你比较清楚地了解你是怎样使用你的时间的。此外，它还能让你安排好各种活动，既有足够的时间工作，也有足够的时间娱乐。 2．寻找一个合适的地方学习。选定某个地方作为你的“学习区”。这可以是家里或者学校图书馆里的一张书桌或者一把椅子，但它应该是舒适的，而且不该有干扰。在你开始学习时，你应能够全神贯注于你的功课。 3．阅读之前先略读。这就是说，在你仔细阅读一篇文章之前，先把它从头至尾迅速浏览一遍。在预习材料时，你就对它的内容及其结构有了大致的了解。随后在你正式开始阅读时，你就能辨认出不太重要的材料，并且可以略去某些章节不读。略读不仅使你的阅读速度提高一倍，还有助于提高你的理解能力。< 4．充分利用课堂上的时间。上课时注意听讲意味着课后少花力气。要坐在能看得见、听得清的地方。要作笔记来帮助自己记住老师讲课的内容。 5．学习要有规律。课后要及早复习笔记。重温课堂上提到的要点，复习你仍然混淆不清的

应用化学专业英语翻译完整篇

1 Unit5元素周期表 As our picture of the atom becomes more detailed 随着我们对原子的描述越来越详尽，我们发现我们陷入了进退两难之境。有超过100多中元素要处理，我们怎么能记的住所有的信息？有一种方法就是使用元素周期表。这个周期表包含元素的所有信息。它记录了元素中所含的质子数和电子数，它能让我们算出大多数元素的同位素的中子数。它甚至有各个元素原子的电子怎么排列。最神奇的是，周期表是在人们不知道原子中存在质子、中子和电子的情况下发明的。Not long after Dalton presented his model for atom( )在道尔顿提出他的原子模型（原子是是一个不可分割的粒子，其质量决定了它的身份）不久，化学家门开始根据原子的质量将原子列表。在制定像这些元素表时候，他们观察到在元素中的格局分布。例如，人们可以清楚的看到在具体间隔的元素有着相似的性质。在当时知道的大约60种元素中，第二个和第九个表现出相似的性质，第三个和第十个，第四个和第十一个等都具有相似的性质。 In 1869,Dmitri Ivanovich Mendeleev,a Russian chemist, 在1869年，Dmitri Ivanovich Mendeleev ,一个俄罗斯的化学家，发表了他的元素周期表。Mendeleev通过考虑原子重量和元素的某些特性的周期性准备了他的周期表。这些元素的排列顺序先是按原子质量的增加,,一些情况中, Mendeleev把稍微重写的元素放在轻的那个前面.他这样做只是为了同一列中的元素能具有相似的性质.例如,他把碲(原子质量为128)防在碘(原子质量为127)前面因为碲性质上和硫磺和硒相似, 而碘和氯和溴相似. Mendeleev left a number of gaps in his table.Instead of Mendeleev在他的周期表中留下了一些空白。他非但没有将那些空白看成是缺憾，反而大胆的预测还存在着仍未被发现的元素。更进一步，他甚至预测出那些一些缺失元素的性质出来。在接下来的几年里，随着新元素的发现，里面的许多空格都被填满。这些性质也和Mendeleev所预测的极为接近。这巨大创新的预计值导致了Mendeleev的周期表为人们所接受。 It is known that properties of an element depend mainly on the number of electrons in the outermost energy level of the atoms of the element. 我们现在所知道的元素的性质主要取决于元素原子最外层能量能级的电子数。钠原子最外层能量能级（第三层）有一个电子，锂原子最外层能量能级（第二层）有一个电子。钠和锂的化学性质相似。氦原子和氖原子外层能级上是满的，这两种都是惰性气体，也就是他们不容易进行化学反应。很明显，有着相同电子结构（电子分布）的元素的不仅有着相似的化学性质，而且某些结构也表现比其他元素稳定（不那么活泼） In Mendeleev’s table,the elements were arranged by atomic weights for 在Mendeleev的表中，元素大部分是按照原子数来排列的，这个排列揭示了化学性质的周期性。因为电子数决定元素的化学性质，电子数也应该（现在也确实）决定周期表的顺序。在现代的周期表中，元素是根据原子质量来排列的。记住，这个数字表示了在元素的中性原子中的质子数和电子数。现在的周期表是按照原子数的递增排列，Mendeleev的周期表是按照原子质量的递增排列，彼此平行是由于原子量的增加。只有在一些情况下（Mendeleev注释的那样）重量和顺序不符合。因为原子质量是质子和中子质量的加和，故原子量并不完全随原子序数的增加而增加。原子序数低的原子的中子数有可能比原子序数高的原

汽车专业英语课文翻译4

Fuel Supply System of Gasoline Engine(UNIT SEVEN) All the gasoline engines have substantially identical fuel systems and run on a mixture consisting of fuel vapor and air. The fuel system comprises the units designed to store, clear and deliver fuel, the units intended to clean air and a unit for preparing a mixture from fuel vapor and air. In a fuel system different components are used to supply fuel from the fuel tank into the engine cylinder. Some of the important components are fuel tank, fuel pump, fuel filter, carburetor, intake manifold and fuellines or tubes connecting the tank, pump and the carburetor. The fuel tank is a fuel container used for storing fuel. It is made of sheet metal. It is attached to the vehicle frame with metal traps and is located at the rear of the vehicle. They are mounted in a boot or boot-floor pan in case of front-engined cars and small commercial vehicles. In order to strengthen the tank as well as to prevent surging of fuel when the vehicle rounds a curve of suddenly stops, baffle plates are attached to the inside of the tank. A cap is used to close the filler opening of the tank. The fuel line is attached at or near the bottom of the tank with a filtering element placed at the connection. The other components of the fuel tank are the fuel gauge sending unit, a vent pipe, receiving unit. To prevent the dirt and water from entering the luggage compartment, a sealing strip is fitted between the fuel tank and boot floor pan. Moreover to limit the transmission of frame distortion to the tank giving rise to squeaking as the metal parts get rubbed together, rubber or felt pads are often fitted between the mountings and the tank. Provision is also made against drumming of the tank by these mountings. The tank may be placed at the side of the chassis frame for convenience in case of large commercial vehicles. The length of the connecting lines or tubes from the tank to the carburetor is also restricted by this at the same time. A porous filter is attached to the outlet lines. By drawing fuel from the tank through the filter, any water in the bottom of the tank as well as any dirt into the fuel gathers on the surface of the filter. To keep the fuel always under atmospheric pressure, the filter pipe or tank is vented. In order to prevent dirt in the fuel from entering the fuel pump or carburetor, fuel filters and screens are used in the fuel system. If the dirt is not removed from the fuel, the normal operation of these units will be prevented. The engine performance will also be reduced.