科技英语翻译练习答案(重排版)
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科技英语翻译 1.1 翻译的标准 第1节 翻译练习1 The power plant is the heart of a ship. The power unit for driving the machines is a 50-hp induction motor. 动力装置是船舶的心脏。 驱动这些机器的动力装置是一台50马力的感应电动机。 第1节 翻译练习2 Semiconductor devices, called transistors, are replacing tubes in many applications. Cramped conditions means that passengers’ legs cannot move around freely. All bodies are known to possess weight and occupy space. 半导体装置也称为晶体管，在许多场合替代电子管。 我们知道，所有的物体都有重量并占据空间。 空间狭窄，旅客的两腿就不能自由活动。 第1节 翻译练习3 The removal of minerals from water is called softening. A typical foliage leaf of a plant belonging to the dicotyledons is composed of two principal parts: blade and petiole. 去除水中的矿物质叫做软化。 双子叶植物典型的营养叶由两个主要部分组成：叶片和叶柄。 1.2 对译者的要求 第4节 翻译练习1 Einstein’s relativity theory is the only one which can explain such phenomena. All four (outer planets) probably have cores of metals, silicates, and water. 爱因斯坦的相对论是能解释这种现象的唯一理论。（直译） 这四颗外层行星的内核可能都由金属、硅酸盐和水构成。（意译） The designer must have access to stock lists of the materials he employs. Part adjustment and repair must be performed on regular basis if an acceptable printed product is to be the end product. 设计师必须备有所使用材料的储备表。（意译） 要使印刷品的质量达到要求，部件调试及修理就必须定期进行。（意译） 第4节 翻译练习2 The most important of the factors affecting plant growth is that it requires the supply of water. The doctor analyzed the blood sample for anemia. The apparent change in size of the sun is caused by dust in the air near the horizon. 植物生长的各因素中最重要的是水的供应。（合译） 太阳的大小看起来有变化，这是由于靠近地平线的空气中有尘粒而引起的。（分译） 医生对血样作了分析，看是不是贫血症。（分译） These fragments of rock and iron range from thousand kilometers in diameter to less than one. Manufacturing processes may be classified as unit production with small quantities being made and mass production with large numbers of identical parts being produced. 这些石块和铁块的碎片大小不等，大的直径有1000公里，小的不到1公里。（分译） 制造过程可以分为单件生产和大量生产。前者指的是生产少量的零件，后者则是指生产大量相同的零件。（分译） 第4节 翻译练习3 Cartography is the science of making maps. Many elements in nature are found to be mixtures of different isotopes. 制图学是研究绘制地图的科学。（增译） 人们发现，自然界里许多元素，都是各种不同的同位素的混合物。（增译） The two units used most frequently in electricity are ampere and volt: this is the unit of voltage and that of current. That like charges repel but opposite charges attract is one of the fundamental laws of electricity. 电学上最常用的两个单位是安培和伏特：后者是电压的单位，前者是电流的单位。（增译） 同性电荷相斥，异性电荷相吸是电学的一个基本规律。（省译） 第4节 翻译练习4 Almost any insulated body processes to some extent the ability to retain for a time an electric charge. The angular contact bearing provides a greater thrust capacity. The properties of the weld can be altered by varying the grain orientation. 几乎任何一种绝缘体都多少具有保留电荷一段时间的能力。 向心推力轴承有较大的轴向承载能力。 通过改变晶粒的方向可以改变焊缝的性能。 2.1 词义的选择 第1节 翻译练习1 The spindle rotates simultaneously round two axes at right angles to each other. The earth isn’t completely round; it is slightly flattened at the poles. In each round of operation the particle picks up energy from the oscillating electric field. 锭子同时绕两个互相垂直的轴旋转。（介词） 粒子每运转一周都从振荡电场获取新的能量。（名词） 地球并非完全是圆的，它的两极略扁平。（形容词） An electron is an extremely small corpuscle with negative charge which rounds about the nucleus of an atom. Her waist measures forty inches round. 电子是绕原子核转动且带有负电荷的极其微小的粒子。（动词） 她腰围40英寸。（副词） 第1节 翻译练习2 Rate of penetration was found to be proportional to the net pressure applied by the tool. Scientists are constantly striving to find fast and convenient way of obtaining quantitative data. To find the area of a square or oblong, you merely multiply its length by its width. Certain isotopes are not found in nature. 人们发现钻孔速度与工具所受的净压力成正比。 求一正方形或长方形的面积，你只需将其长度乘以宽度。 科学家们总是力求找到快速而简便的方法获得定量数据。 有些同位素在自然界中并不存在。 New fibers find expanding applications in engineering and industry. Kangaroos are found in Australia. This plant is found in the sea near the mouth of rivers. Microcomputers have found their application in the production of genius sensors. Plastics find wide application in our daily life. 大袋鼠产于澳大利亚。 这种植物生长在近河口的海中。 新发明的纤维在工程和工业领域得到越来越广泛的应用。 微型计算机已经应用于智能传感器的生产中。 塑料在我们的日常生活中得到广泛应用。 第2节 翻译练习1 The cause of rolling resistance is the deformation of mating surfaces of the rolling element and the raceway on which it rolls. Traditionally, NC programming has been performed offline with the machine commands being contained on a punched tape. The occurrence of large mats of floating algae may result in the death of many fish from lack of oxygen. 滚动阻力的起因在于滚动体的配合面和它滚动的滚道的变形。（技术性引申） 通常，数控机床的编程是脱机完成的，指令载于穿孔带上。（技术性引申） 大片大片漂浮的藻类的出现导致很多鱼因缺氧而死亡。（修辞引申） The splitting of the uranium or plutonium nucleus is accompanied by the release of very considerable amount of energy. The major contributors in component technology have been in the semiconductor. The distance between the two plates is small compared with their linear dimensions. Just as different solids and liquids vary in density, so do gases and vapors. 元件技术中起主要作用的是半导体元件。（具体化引申） 两板之间的距离相对于其宽度和长度而言比较小。（具体化引申） 随着铀核和钚核的裂变，会有极其巨大的能量释放处理。（修辞性引申） 正像不同的固体和液体的密度不同一样，不同的气体和蒸汽的密度也不同。（具体化引申） The Curies believed that there was something in nature that gave out radiation. Obviously, there is much room for the improvement in the structure. At present coal is the most common food of a steam plant. The facts have been set down in black and white. 显然，其结构还有较大的改进余地。（抽象化引申） 目前，煤是火电厂最常用的能源。（抽象化引申） 居里夫妇坚信，自然界中有一种物质能放出辐射能。（具体化引申） 这些事实已经清清楚楚地记录下来了。（抽象化引申） 2.3 词类的转换 第3节 翻译练习1 Each time a sample was drawn for color determination. What is certain is that the oil spill has delivered a devastating blow to the ecology of the Persian Gulf. We should get familiar with different systems of units. 每次取一个标本测定颜色。 可以肯定，这场石油泄漏事件对波斯湾的生态是个惨重的打击。 我们应该熟悉各种（计量）单位制。 These decision-making processes are applicable to the entire field of engineering design--- not just to mechanical engineering design. Hydrogen instead of air is frequently used for cooling large turbogenerators. When the war was over, it was discovered that the Germans were nowhere near success in developing nuclear weapons. 常以氢气代替空气来冷却大型汽轮发电机。 第二次世界大战结束后，人们发现德国人在研制核武器方面离成功还很远。 这些判定过程可以应用于工程设计的整个领域，而不仅仅限于机械工程设计。 Various precautions have been taken against leakage. Once inside the oven, panels are subjected to a temperature of 365°F. Value is defined as a numerical ratio, the ratio of the function, or performance, to the cost. This new model should appeal to potential buyers. 一旦进入烘干炉，板材就处于365华氏度的温度条件下。 价值的定义是功能或性能与成本的数值比。 已采取了各种措施防止渗漏。 这种新式样对潜在的买主肯定有吸引力。 Galileo’s experiments are not difficult, nor is there any evidence that he performed them with exceptional skill. Sometimes a scientist observes an object and its features, for example a star or a bird; sometimes he observes an event, which is something that happens at a particular time. Earthquakes are generally more destructive of life than volcanic eruptions. 有时科学家观察一物体及其特征，例如一颗星或一只鸟；有时科学家观察某一事件，即在一特定时间所发生的事。 地震对于生命的破坏通常大于火山爆发。 伽利略的实验并不难，也没有证据表明他是以非凡的技能来做实验的。 Heat should be applied slowly to avoid localized overheating. How rapidly a fuel burns depends on how thoroughly it is mixed with oxygen or air. This is why a coil is often referred to as an inductor. 一种燃料燃烧的速度有多快，取决于它与氧气或空气混合的均匀程度。 这就是线圈常被叫做电感器的原因。 应当慢慢加热，以避免发生局部过热现象。 第3节 翻译练习2 Practically all of the useful properties of materials are strongly dependent on their internal structure. The metal casts well. A wire for conducting electric current is covered with plastic; the plastic is insulation round the wire. 几乎材料的一切有用特性都与其内部的结构有密切的关系。 这种金属有良好的铸造性能。 传导电流的导线包有塑料，该塑料便是导线周围的绝缘材料。 There are many ways of determining the distribution of the magnetism about a magnet. Good lubrication keeps the bearings from being damaged. Safety in a power plant is of great importance. Most modern transmitters employ solid state circuits. 安全在电厂是非常重要的。 现代发报机大多采用固体电路。 有许多方法来确定磁场周围的磁力分布状况。 润滑良好可保护轴承不受损伤。 E-Chemmerce now offers two main levels of online business intelligence on chemical, plastic and energy e-commerce. These images tend to exaggerate the robot’s similarity to human anatomy and behavior. Aluminum remained an expensive rarity till the discovery of the electrolytic process for reducing aluminum in 1886. 这些概念常常夸大了机器人与人类在形体和行为方面的相似之处。 《电子化工商务》目前主要提供两个层次的有关化学、塑料和能源电子商务的在线商务信息服务。 直到1886年人们发现电解法还原铝之前，铝一直是一种昂贵的珍品。 Since some materials are not damaged easily as others, the possibility exists of developing radiation-resistant parts. 由于有些材料不像另一些那样容易被损坏，所以有可能研制出防辐射的零件。 2.4 词的增译 第4节 翻译练习2 第4节 翻译练习1 This action externally appears like the discharge of a capacitor. Once out of the earth’s gravity, an astronaut is affected by still another problem--- weightlessness. By minimizing the microscopic imperfections scientists are making far stronger ceramics. 这一作用从外表上看来像电容器的放电现象。 一旦离开了地球的引力范围，宇航员又遇到了另一个问题——失重。 科学家们正通过最大限度地减小微观缺陷来制造强度高得多的陶瓷。 Atomic cells are small and very light, as compared to ordinary dry ones. Transistors can make previously large equipment much smaller. Astronomers have evidence of a few other stars too, which might have black holes as companions. 天文学家有证据表明，还有其他一些恒星也可能有黑洞作为伴星。 和普通电池相比，原子电池体积小、重量轻。 晶体管能使原先体积大的设备变得小得多。 The key to the new materials is researchers’ increasing ability to manipulate substances at the molecular level. The largest and most expensive products cannot, because of their size, be testable in the factory. Cold rolling enables the operators to produce rolls of accuracy and uniformity, and with a better surface finish. 最大最贵的产品，因为体积大，在该工厂里是不能检验的。 开发新材料的关键在于研究人员不断提高在分子一级上处理物质的能力。 冷轧可使操作工生产出精确度高、均匀度好的轧制件，并具有更好的表面光洁度。 All these factors play a key role in formulation of the model. PCs are not the most stable, and with video editing you have to be extra careful. This method makes it easy to identify the various components. 在拟订模型时，所有这些因素都将起到关键性的作用。 这个方法使人们很容易识别各种不同的构成成分。 个人电脑一般并不太稳定，所以，进行视频编辑时需要加倍小心。 第4节 翻译练习2 It was estimated that the power of an average horse is equal to 500 feet-pounds per second. Panel patch is one gauge heavier than thickness of original skin. Studies have shown that information can be communicated to people many times faster in a graphic form than in written form. 据估计，一匹普通马的功率等于500英尺-磅力/秒。 补块比原板的厚度大一号。 众多研究表明，以图形表示的信息被人们接受的速度比以文字表示的快许多倍。 The chemist is making an analysis of the poison. It appears that the construction of the dam has had a considerable effect on the ecology of the region. The receiver will operate reliably no matter what happens. 无论发生什么情况，这台接收机都将可靠地工作。 药剂师正对毒性进行分析。 看来，建造水坝对这一地区的生态已经有相当大的影响。 Radiant, electrical and chemical energies can all be turned into heat. The frequency, wave length and speed of sound are closely related. Noise figure is minimized by parametric amplifier. 频率、波长和声速三者是密切相关的。 辐射能、电能和化学能这三种能均可转变为热能。 采用参量放大器即可将噪音系数减小至最低限度。 In the absence of sufficient knowledge confusion exists in classifying a specimen as a butterfly or a moth. Lead can be hammered into very thin sheets without being broken. There are a number of devices that give an electric current when light falls on them, without any chemical changes taking place. 如果没有足够的知识，就分不清标本是属蝶类还是蛾类。 有许多器件在受光照射时能产生电流，但不发生任何化学变化。 铅能被锤成很薄的薄片而不破裂。 2.5 词的省译 第5节 翻译练习1 The fact that the concrete is slow in setting is no sign that it is of poor quality. Such an engine is called an internal combustion engine. The symptoms of hepatitis are similar no matter which virus is involved. 混凝土凝固得慢并不表示其质量差。 这种发动机成为内燃机。 肝炎不管是由何种病毒引起的，其症状均大同小异。 This critical deficiency was itself due to three factors which interacted with each other over the entire period. The properties change in going from carbon to graphite. The design choices hinge upon considerations of gain, noise figure, and so forth. 设计选择的关键在于考虑增益、噪音系数等等。 这个关键性的逆差来源于三个始终互相影响的因素。 碳转变成石墨时，其性质也发生了变化。 Temperatures may reach 700°C and surface oxidation becomes critical. If the atomic nucleus of a heavy element is split, a large amount of energy is released. The discovery of enzymes is very important because it gave impetus to a series of experiments. 分裂一重元素的原子核，会释放出很大的能量。 温度高达700摄氏度，表面氧化便成为关键问题。 酶的发现很重要，因为它推动了一系列试验的进行。 Apart from the fact that it may become hot, no apparent change occurs in a metal when it is carrying a current. This equipment forms an integral part of many advanced systems. There was a rise in temperature, and as a result, the component failed. 金属有电流通过时，除了金属可能变热外没有什么显著变化。 温度升高了，结果元件出了故障。 这个设备是许多先进系统不可缺少的一部分。 If there is little cooling water available, a diesel engine makes an excellent prime mover for generation below 10,000 kVA. There was a block in the pipe and the water could not flow away. 如果能利用的冷却水不多，则柴油发动机可以成为极好的发电10000千伏安以下的原动机。 水管被东西堵住，水流不出去。 2.6 重复法 第6节 翻译练习1 The properties of gas are quite different from those of liquid. The electric resistance of copper is not so large as that of iron. The three gas laws are true of all gases, as well as of air. 气体的性质与液体的性质大不相同。（重复名词） 气体三定律不但适用于空气，也适用于所有气体。（重复动词） 铜的电阻不像铁的电阻那样大。（重复名词） Matter changes not only in state but also in volume. Continuous data can be expressed in either fractions or whole numbers. 物质不仅形态改变而且体积也改变。（重复动词） 连续资料可以用分数表示，也可以用整数表示。（重复动词） 3.1 名词的译法 第1节 翻译练习1 In an unusual application, this organization uses a fingerprint scanner to monitor the comings and goings of its residents. A capacitor is used to eliminate sparking when a circuit containing inductance is suddenly opened. 一个不同寻常的用途是：这个机构使用指纹扫描器监视居住人员的进出。 当含有电感的电路突然断开时，可用电容器消除火花。 第1节 翻译练习2 The comparison reveals that the error is due to aliasing. The scans confirmed that the subjects’ brains dealt with words in ways that contradict one hoary old idea. The latest research with radioactive isotopes has shown that this assumption is quite wrong. 比较结果表明，误差是由于名称不同而造成的。 扫描结果证实，受试者的大脑处理词的方式同一种古老的旧观念不一致。 对放射性同位素的最新研究结果表明，这种设想是完全错误的。 Metals differ in the ease with which they give up electrons and enter into chemical combination. Internal-shoe drum brakes provide better protection from water and dust. People on earth are protected from the dangerous ultraviolet radiation of the sun by a layer or ozone that spans the planet and absorbs the radiation. 各种金属放出电子和参与化学反应的难易程度不一。 内蹄式鼓形制动器的防水、防尘性能比较好。 地球上的人们受到包围着地球并能吸收辐射的一层臭氧层的保护，从而免受危险的太阳紫外线辐射的伤害。 According to the molecular theory the temperature of an object depends on the average speed of its molecules. Effectiveness of temperature control depends upon the amount of lubricant supplied, the ambient temperature, and the external cooling. 根据分子理论的原理，物体的温度取决于其分子的平均速度。 温度控制的效果取决于润滑剂的用量、环境温度以及外部的冷却设施。 第1节 翻译练习3 Particular attention should be given to hoses to ensure that chafing does not occur. The primary concern of electrical engineering is the doing of work by the delivery of energy. Gene piracy is not new. All plants and animals need carbon for growth. 要特别注意软管，保证没有擦伤。 窃取基因不是新鲜事。 电工学主要关注的是通过输送能量做功的情况。 所有动植物均需要碳才能生长。 第1节 翻译练习4 The experiment was a success. Semiconductor devices can perform a variety of control function in electronic equipment. 这个试验是成功的。 半导体在电子设备中能起各种各样的控制作用。 3.2 冠词的译法 第2节 翻译练习1 A polymer is a substance of high molecular weight. Being a good insulator, rubber is often used in cables. The patient was administered the mixture twice a week. These machines may be oiled once or twice a month. 聚合物是一种高分子的物质。 这种混合剂病人每周服用两次。 橡胶是一种良好的绝缘体，所以经常使用在电缆上。 这些机器每个月可以加一次或两次油。 第2节 翻译练习2 A bearing can be defined as a member specifically designed to support moving machine components. Use a transformer and power at low voltage can be changed into power at high voltage. An object at rest has no kinetic energy, its velocity being zero. 轴承可以定义为一种专门用于支撑运动着的机器零件的构件。 静止的物体没有动能，因为它的速度为零。 使用变压器可将低压电转变为高压电。 第2节 翻译练习3 作为固定词组时的省译： on a large scale a majority of a wealth of as a result 结果，因此 大规模地 大多数的 大量的 第2节 翻译练习4 The machine is intended for grinding the top and bottom surfaces of tungsten carbide tips. The mechanism has been termed cumulative feedback inhibition. 该机床是供磨削硬质合金刀片上下表面用的。 这种机制就叫做累加反馈抑制。 第2节 翻译练习5 The basic job of the computer is the processing of information. The main effect is to raise the fundamental slosh mode frequency. 计算机的基本任务是处理信息。 主要作用在于提高基本的晃动频率。 第3章 总复习题 Other factors affect the configuration of the total system. In normal flight the hatch doors fair into the fuselage. Energy can neither be created, nor destroyed by any means known to man. 另一些因素则将影响整个系统的结构。 飞行正常时，舱门与机身平整贴合。 用人们已知的方法，既不能创造能量也不能消灭能量。 It is customary to refer to design levels as high or low on component complexity. The main economy of the system stems from the ability to move cars in a continuous train without uncoupling. He is a stranger to the operation of the electronic computer. 他对电子计算机的操作是陌生的。 习惯上根据部件的复杂程度把设计级称为高设计级和低设计级。 此系统的主要经济之处在于它能移动列车的车厢而不必将它们脱钩分开。 A key element in system capacity planning is the financial cost of performance. The assembler can expand the key words in the assembly code into their full instruction set. The flame does not touch the flask directly. 这种汇编程序能把汇编码中的关键字扩展成完整的指令集。 系统能力计划中关键因素是性能的金融成本。 火焰没有直接接触烧瓶。 The study of the strength of solids involves the study of the defects in the crystalline structure. The problem was solved by the provision of a compensating jet. The rusting of iron is the slow chemical combination of the elements iron and oxygen in moist atmosphere. 研究固体的强度，就必须研究晶体结构中的缺陷。 铁生锈是铁元素和氧元素在湿空气中缓慢化合的现象。 通过安装一个补偿喷嘴，解决了这个问题。 The decay of organic matter is a slow oxidation by oxygen in the air. In order to improve a certain kind of battery, Edison spent almost ten years and made nearly 50,000 experiments. 有机物的腐烂是空气中的氧引起的一种缓慢氧化过程。 为了改善一种电池的性能，爱迪生花了差不多十年时间，做了近50000次试验。 4.1 代词的一般译法 第1节 翻译练习1 In this cell the light incident on the sensitive surface of the cell causes the photo-electric emission of electrons from the surface, and these electrons are attracted to the other electrode. The owl can hear a mouse chewing and fly down on it, even though it is hidden from sight under a pile of leaves. 在这种电池中，照在电池光敏表面光电效应而发射电子，而这些电子被吸引到另一电极。 即使老鼠躲藏在一堆叶子下看不见的地方，猫头鹰也能听见老鼠咀嚼的声音而飞下来袭击它。 This might be compared with the mumble of wavelengths of sound that go to make up ordinary noise. 这可以与杂乱的声波相比，一般的噪音就是由这种杂乱的声波组成的。 第1节 翻译练习2 Drawing electrons away from the atom causes it to have a net positive electric charge. Each crystal should have a shape as much like that of the other crystals as possible. 将电子与原子分离会使原子带上纯净正电荷。 每一结晶的形状应与其他结晶的形状尽可能相似。 第1节 翻译练习3 Every element retains its identity no matter how it is finely divided. Astronomers can estimate the size and brightness of a star by its color. 每种元素不论分得怎样细小，它仍保持其特征。 天文学家根据恒星的颜色可以估计它的大小和亮度。 第1节 翻译练习4 Many processes have already been proposed, and one possible future process is a smelting reduction. It is possible to work backward from the known strength and determine what factor of safety was used. Each is a solid sphere with a metallic core surrounded by silicate shells. 我们能够由已知的强度反过来求出所用的安全系数。 它们每一颗都是由硅酸盐外壳包围着金属内核的固态球体。 人们已经提出了很多方法，未来可能的选择之一就是熔融还原法。 第1节 翻译练习5 In this chapter our task is to find out what the air is made of. Today we have a fairly clear idea of what goes on inside of atom. Practically all of the heat energy received by the earth comes from the sun. 现在我们对原子内部的情况已相当清楚了。 地球所得到的热能几乎都来自于太阳。 在这一章中，我们的任务是弄清空气的构成成分。 4.2 人称代词的译法 第2节 翻译练习1 You can decide what resolution and compression level is best for your output. We’ll do everything possible to improve the supply of electricity. You can find the density of a body providing you know its mass and volume. We must be very careful to avoid trying to express energy in terms of power units. 我们将尽一切努力来改善电力供应。 只要知道物体的质量和体积，就可求出物体的密度。 你可以决定哪种溶解和压缩程度对成品最好。 必须注意避免用功率单位表示能量。 第2节 翻译练习2 It may require the taking of a large sample as in macro analysis. If an atom contains three protons, it must have three electrons to be electrically neutral. 如果一个原子有三个质子，这个原子必然有三个电子来使其呈电中性。 它可能要求像宏观分析中那样采用大的样本。 4.3 形容词性物主代词的译法 第3节 翻译练习1 The density of anything is its mass per unit volume. Each substance shows an individual structure of its own. One of the drawbacks of the early lasers was their inability to operate continuously. 每一种物质都显示出它自己的独特结构。 任何物体的密度是它的每单位体积的质量。 早期激光器的缺点之一是它们不能连续地工作。 第3节 翻译练习2 In their workshop there is no one who understands how a computer uses its tubes. Transistors are more advantageous to vacuum tubes for their being small and light. The transformer cannot be called a machine because of its having no moving parts. 晶体管优于真空管，因为它尺寸小、重量轻。 在他们车间，无人能理解计算机是怎样使用其电子管的。 变压器不能称为机器，因为它没有转动的部件。 第3节 翻译练习3 According to their ability to conduct electric current, all materials may be classified into three major categories: conductors, semiconductors and insulators. You shouldn’t have touched the wire with your wet hands. 你不该用湿手触摸导线。 根据导电的性能不同，所有的材料可分为三大类：导体、半导体和绝缘体。 第3节 翻译练习4 Heating semiconductors means increasing their conductivity. Triangles can be classified according to their angles or the relative lengths of their sides. According to their composition, these raw materials may be separated into three groups. The brain has its managing system. 三角形可按照其角度或其相对边长来分类。 根据这些原材料的构成成分，它们可以分为三种类型。 加热半导体就会增加其导电率。 大脑有自己的管理系统。 4.4 指示代词的译法 第4节 翻译练习1 All atoms, except those of hydrogen, contain one or more neutrons in the nucleus. The speed of the object approaches that of light. The geometry of the test specimens differs from the geometry of those used in tension tests. 所用试件的形状和尺寸与拉伸试验的试件不同。 除了氢原子外，所有的原子都有一个或几个中子。 该物体的速度接近光速。 第4节 翻译练习2 It diffracts the diffracted beam and this means that it generates an inverse transform. Heat is a form of energy and that is known to all of us. They used the transformers of poor quality, and this caused the whole power supply system break down. 他们用了一批劣质的变压器，使得整个供电系统陷于瘫痪。 热是能的一种形式，这是大家都知道的。 它对衍射光束发生衍射，这意味着它产生了一个逆变换。 第4节 翻译练习3 This is a simple criterion that guarantees the existence of such a representation. The percentage of such cases among surgical patients can be determined in the following manner. 在接受手术的病人中，这样的病例所占的百分比可用下述方法确定。 这是确保这种等值表达式存在的一个简单标准。 第4节 翻译练习4 As a rule solids and liquids expand when heated, water does the same except near its freezing point. The same is true when an alternating voltage is applied to a resistance. 按照固体和液体遇热膨胀的原理，水除了接近其冰点的情况之外也是如此。 当交流电压加在电阻上时，情况也是一样的。 第4节 翻译练习5 All motion in this universe is the form of successively rising and falling. Series do have the advantage of increasing resistance to reduce current when this is desirable. 串联电路的确有这样的优点：在需要时可以增加电阻来减少电流。 宇宙内的一切运动，均处在连续上升和下降的状态中。 4.5 不定代词的译法 第5节 翻译练习1 All these elements can be used in semiconductor manufacture. All transformers and electric machinery use magnetic material. All the shafts were cut from heavy planks of wood. 所有的变压器和电机都使用磁性材料。 在半导体生产中，所有这些元件都能用上。 箭杆都是用厚木板削制而成的。 Almost all who die of AIDS actually die of starvation. All the currents at node were not to add up to zero. Not all the energy from an antenna is radiated in the main beam. Not all people who test positive for the AIDS antibody get the disease AIDS. 几乎所有丧命爱滋病的患者都是死于饥饿。 并非所有节点上的电流总和为零。 天线能量并不都是由主波束辐射的。 并不是所有的爱滋病抗体试验为阳性的人都患有爱滋病。 第5节 翻译练习2 The equipment will compensate for any dimensional variations caused by wheel wear. Any portion of the flight control system may be readily removed in any sequence by the removal of attaching bolts and nuts. Which, if any, of the three statements below are false? 拆卸了原装的螺钉及螺母，便可很快地按任意顺序拆除飞机控制系统的任何部分。 该装置对砂轮磨损引起的任何尺寸误差给予补偿。 下面三种说法中如果有错，那么是其中的哪一种？ What, if any, effect do you feel the imports of Canadian gas will have on the American producer? There are few, if any, of them know the construction of the transformer. 你觉得进口加拿大的天然气对美国的生产者可能产生什么影响吗？ 他们当中几乎没人懂得变压器的结构。 第5节 翻译练习3 Both alternatives are presented on the screen. Velocity is a vector quantity involving both magnitude and direction. 速度是一种矢量，既有大小，又有方向。 两种选择都在屏幕上显示出来了。 第5节 翻译练习4 Each of the bits has a different optimum cutting speed. There are many types of efficient water pumps, each designed to meet a specific need. Every element, no matter how it is finely divided, retains its identity. 效率高的水泵有多种类型，每一种都用来满足某个特定的需要。 每个钻头都有一个不同的最佳切割速度。 每种元素不论分得怎样细小，仍保持该元素的特征。 One half of the medium was renewed every three days. It has an error rate of one or two words in every hundred. Not every minute difference is noted. 每三天更换一半溶剂。 误差率是每百字有一两个错误。 并非每一个细微的差别都被注意到了。 第5节 翻译练习5 Without electricity neither machine could be stared. I believe either method will do. 我看两种方法中的任何一种都行。 没有电，这两台机器都开动不了。 第5节 翻译练习6 Sometimes one finds in fossil stones the imprint of a leaf. The last sound to reach the receiving ship is the one that hits the basement. Neutrinos from a subsidiary decay process are the ones to be detected. 传到接收船上的最后的声音就是碰到底层的声音。 有时人们能在化石里发现一片树叶的痕迹。 有待探测的中微子来自次要的衰变过程。 Driving machines are always the opposite of driven ones. One of the most successful methods of achieving this depends on the use of fluidization. One of the uses of the triode is that it can amplify. 主动机和从动机总是相反的。 达到这一目的的最成功的方法之一就是采用流化技术。 三极管的用途之一是放大。 Ones who make the decisions on what went into the system are programmers. Ones who claim ECT is both effective and safe, in fact, cannot prove it. There are two 300MW thermal power units in this power plant. One is made in China; the other is imported from Germany. 决定要把什么写进系统的人是专业编程人员。 那些宣称电痉挛疗法既有效又安全的人，实际上并无法证明他们的观点。 这家电厂有两台30千瓦火力发电机组，一台是国产的，另一台是从德国进口的。 There are two kinds of electric currents. One is the direct current; the other is the alternating current. 电流有两种，一种是直流电流，另一种是交流电流。 第5节 翻译练习7 This chemical is poisonous. Others are poisonous, too. Some parts require a hard, tough metal and others may be made of softer metals. The coolant serves no other purpose than to remove excess heat. Some atomic nuclei undergo spontaneous disintegration while others do not. 冷却剂除了排除多余的热以外没有任何其他用处。 这些化学制品有毒，别的化学制品也有毒。 有些零件需要由硬的韧性金属制成，而有些则可由软的金属制成。 有的原子核会同时裂变，而另外一些却不会。 第5节 翻译练习8 Another method is available to increase the system capacity. Heat is always being transferred in one way or another, where there is any difference in temperature. 凡有温差的地方，热都会以这样或那样的方式传输。 还有另一种可增加系统容量的方法。 第5节 翻译练习9 Some metals burn more readily than others. To specify a distance, we must use some unit of length. When an object is warmer than the surrounding region, it loses some of its heat by radiation. The particles require some a day to reach the earth. 为了确定距离，我们必须使用某种长度单位。 有些金属比另一些金属更容易燃烧。 当一个物体比周围环境热时，该物体会通过辐射失去它的一些热量。 这些粒子大约需要一天的时间才能到达地球。 4.6 it及其句型的译法 第6节 翻译练习1 It moves or rotates by a fixed amount each time an electrical pulse is applied to it. To help avoid information overload, it (virtual convergence) will do this intelligently. The earth rotates as it travels through space. As current flows through a conductor, it sets up a magnetic field. 为了避免信息过载，它（虚拟连接）将会智能化地进行操作。 对它每加一个电脉冲，它就移动或旋转一个固定的量。 地球在空间运行时，它还要自转。 电流通过导体，便产生磁场。 第6节 翻译练习2 It is a $12-billion industry whose factories, numbering in the hundreds, are found all over the world. It is twenty meters in height. 那个行业资金达120亿美元，工厂有上千家，遍布世界各地。 高度为20米。 第6节 翻译练习3 It is very far to the airport. It is raining hard. 到机场很远。 雨下得很大。 第6节 翻译练习4 It is recommended that the screw be used to increase accuracy of measurement. By using a laser, it is possible to throw very large and very clear television pictures on to a screen. It was pointed out that while the lead obtained from the disintegration of radium possessed all the characteristics of ordinary lead, it differed from it in atomic weight. 使用激光器，可以将很大很清晰的电视图像投射到屏幕上。 建议使用螺杆调节，以提高测量的精确度。 前已指出，虽然由镭蜕变而获得的铅具有普通铅的一切特性，但其原子量与普通铅不同。 第6节 翻译练习5 It necessitates careful design of the apparatus to get rid of the heat. It is unknown when to begin to make transportable transformers. It is interesting to compare the energy needed to place a satellite in orbit with the energy that would be required to cause it to escape. 什么时候开始制造移动式变压器还不知道。 除热需要对设备进行仔细设计。 把一颗卫星送入轨道所需的能量和使卫星脱离地球所需要的能量进行比较是很有意思的。 第6节 翻译练习6 It used to be thought that when you see a word and speak it, several stages of processing are involved. It must be remembered that the condition may be silent until haematemesis, melaena or perforation occurs. It is known that electronic computers play an important part in science and technology. 大家必须记住，在呕血、黑便，或穿孔发生之前，该病可能无症状。 过去人们常常认为一个词从看见到念出来包括好几个处理阶段。 我们知道，电子计算机在科学和技术方面起着重要作用。 第6节 翻译练习7 It follows that any form of preheat adds to the welder’s difficulties and causes discomfort, particularly when welding at high preheat temperature levels inside vessels. It can be concluded that temperatures on the surface of Venus is too hot for life as known on earth. It had been calculated that actual error probability for the value was of the order of 0.5 percent. 由此可见，任何形式的预热都会增加焊工的困难，使他们身感不适，在容器内高温预热下施焊时尤其如此。 可以断定，金星表面的温度过热，地球上的生物是不能适应的。 据计算，这个数值的实际误差概率约为0.5%。 第6节 翻译练习8 It makes no difference when inducing an e.m.f., which moves, the coil or the magnet. It is essential that the body of the machine is effectively earthed. 在感应出电动势时，是线圈运动还是磁铁运动，这没有区别。 这机器的机身必须有效接地，这一点十分重要。 第6节 翻译练习9 The heating effect makes it possible to produce the light. We find it possible to transform a.c. into d.c. by using a rectifier. We think it true that the human body is also a good conductor. 热效应使产生光成为可能。 我们发现能用整流器将交流电变成直流电。 人体也是一种良好的导体，我们认为这点是正确的。 第6节 翻译练习10 It is the voltmeter which we use to measure the voltage. It is through this interface that the substation operator must control and monitor the entire substation. It was not until I came in that he began to repair the old generator. 我们用来测量电压的就是伏特计。 变电站运行人员正是通过这个界面控制和监视整个变电站的。 直到我进来，他才开始修理那台老式发电机。 It was not until the 19th century that heat was considered as a form of energy. 直到19世纪，热才被认为是能的一种形式。 第4章 总复习题 The rise in temperature could not have happened of itself. Be the shape of a body complicated, it is possible to find out its volume. The more energy we desire to send, the higher we make the voltage. The most typical humanlike characteristic of a robot is its arm. 温度上升不可能是出于自身的原因。 不论物体的形状如何复杂，人们均可求出它的体积。 要求输送的电能越多，就得使电压升得越高。 机器人最具人性化的特点就是它的机械臂。 In our studies of the implications for the First Law, we were able to see the importance of the distinction between state and path functions. The first job of an electron tube is to get the electrons apart from their nuclei. That type of turbine usually rotates at a very low speed. 那种汽轮机通常以非常低的速度运转。 我们研究第一定律时，可以明白区分状态函数和路径函数的重要性。 电子管的第一项工作就是使电子与其原子核分开。 Small objects such as dust particles and water droplets fall only small distances before losing most of their acceleration. The same has happened to the central control system. There’s hardly any room for any impurities in such a microfiber. 中心控制系统也发生过同样的事故。 小物体，比如尘粒和水珠，仅仅下落了一小段距离后便失去了其大部分的加速度。 在这种微纤维中，杂质几乎没有存在的可能。 His instances were Lennard and Stark, both of them were Nobel laureates but later became fervent followers of Hitler. The primacy function of a regulator is to supply constant pressure to each device. The best use of these equations is in checking the theoretical analyses using the other approaches. 他举出勒纳德及史塔克为例子。这两个人都得过诺贝尔奖，但后来却成了狂热的希特勒信徒。 这些方程式最大的用处是可对采用了其他方法的理论分析进行检验。 调节器的基本功能是给每个装置提供稳定的电压。 It is desirable to characterize electrical noise as accurately as possible. It is known that local weather can be affected within a few days by meteorological conditions thousands of miles away from here. 需要尽可能准确地表征电噪音。 我们知道，当地的天气在几天内会受到几千英里以外地区气象状况的影响。 5.1 数词的译法 第1节 翻译练习1 Liquid bromine boils at 58°C at which temperature it changes into a reddish-brown gas. Move to the next operation after the voltage reaches 150V. Tests have shown that the energy saving can rise about 40 percent. 液态溴在58摄氏度时沸腾，在这个温度它变成红褐色的气体。 等电压到了150伏时，进行下一个操作。 试验证明，能量节约可增加40%左右。 第1节 翻译练习2 Of many thousands spare parts does not come up to the standard but one. A lot of counties have set up power stations, chemical fertilizer plants and a hundred and one other factories. The periodic table contains more than one hundred chemical elements belonging to eight families. 在几千个备件中，只有一个不合格。 许多县已建立了发电站、化肥厂以及许多别的工厂。 元素周期表由属于8个族的100多个化学元素组成。 These materials become quite soft and flexible below 150°C. An increase in the oxygen content of coal by 1% reduces that calorific value by some 1.7%. Nearly 25 neurotransmitters have been found so far. 这些材料在150摄氏度以下变得十分柔软、易于弯曲。 煤的含氧量每增加1%，其热值就下降约1.7%。 迄今为止，已经发现了大约25种神经传递素。 第1节 翻译练习3 With the result of automation, productivity has increased by 5 times in that factory. The sales of industrial electronic products have increased to six times. The output of the machine tools has multiplied four times. The current has increased by a factor of three. 由于自动化的结果，那个工厂的生产率提高到5倍。 工业电子产品的销售额增加了5倍。 机床产量增加了3倍。 电流增加了2倍。 第1节 翻译练习4 This type of furnace uses 4 times more electricity than that type does. This rod is 4 times longer than that one. The oxygen atom is nearly 16 times as heavy as the hydrogen atom. 这种炉的耗电量是那种炉耗电量的4倍。 这根杆比那根长3倍。 氧原子的原子量几乎是氢原子量的16倍。 The atomic weight of helium is four times heavier than that of hydrogen. In rolling bearing the starting friction is about twice the running friction. 氦原子量比氢原子量重3倍。 滚动轴承的启动摩擦大概是转动摩擦的2倍。 第1节 翻译练习5 The leads of the new condenser are shortened by six times. The operation of cost decreased by five times. The loss of electricity was reduced by a factor of four. The pipe is four times lighter than that one. 新型电容器的引线缩短了5/6。 成本运行降至1/5。 这根管子重量是那根的1/4。 电损减少了3/4。 第1节 翻译练习6 Weld strength can be increased by 45 percent. Tests have shown that the energy consuming can be reduced by 30 percent. The loss of energy has been reduced to less than 10 percent. 焊接强度可增加45%。 试验证明，能量消耗可减低30%。 能量损耗可减至不足10%。 Its grain output was 18 percent higher than that in 1998. The steel output is 30 percent higher than that of last year. 其粮食产量比1998年高出18%。 钢产比去年增加了30%。 第1节 翻译练习7 Ten to one, the experiment is unlikely to produce good results. These figures show that the improvement of molecular refraction is within a factor of ten. 十有八九，这项试验不可能得出好的结果。 这些数字表明分子折射度的改进值为一个数量级。 5.2 形容词的译法 第2节 翻译练习1 Suitable treatment shall be given as soon as possible to avoid hydrogen embrittlement. Complex computer systems are prone to software hitches. The parts must be very strong so that they may not break in use. This kind of steel becomes very hard and very brittle when hardened. 尽快予以适当的处理，以免氢蚀脆化。 复杂的计算机系统容易出现软件故障。 零件必须十分坚固，才不会在使用中破损。 这种钢淬火后就变得很硬很脆。 第2节 翻译练习2 Hydrogen is about one-fourteenth as dense as air. Helium is a very light gas, only twice as heavy as hydrogen. Ice floats because it is not as dense as water. 氢的密度大约是空气密度的1/14。 氦气是一种很轻的气体，重量仅为氢气的2倍。 冰浮起是因为它的密度比水的密度小。 第2节 翻译练习3 In the thermosciences area, the mechanical engineer is concerned with thermodynamics, fluid mechanics, and heat transfer. This in a large measure is responsible for the high accuracy obtainable from such systems. The transmission ratio is dependent upon the ratio of the number of teeth of the meshing gear wheels. 在热学领域，机械工程师关心的是热力学、流体力学和传热学。 在很大程度上，这是从这类系统中获得高精度的原因。 传动比取决于两个啮合齿轮的齿数比。 Once the engine is underway, these auxiliaries are turned off. 发动机一旦启动，这些辅助设备就关闭了。 第2节 翻译练习4 Recent discoveries have been made concerning the peculiar properties of certain semiconductors. Research and development is of particular importance to aerospace industry. In copper and most pure metals there is an appreciable increase in resistance with an increase in temperature. 最近，对于某些半导体的奇怪特性有一些发现。 研究和发展对航空航天工业非常重要。 在铜和大部分纯金属中，随着温度的升高，电阻也会明显增大。 One of the drawbacks of the early lasers was their inability of continuous operation. These metal ions interfere with electron flow and cause a great decrease in electron motion. Lubricating oils are used to ensure the smooth running of the machine. 早期激光器的缺点之一是它不能连续工作。 这些金属离子阻碍电子流动，引起电子运动大幅减弱。 使用润滑油是为了确保机器正常运转。 第2节 翻译练习5 The most common application for bearing is the support of a rotating shaft that is transmitting power from one location to another. The World Wide Web is a unique medium for communication and for publishing. 轴承最常见的应用是支撑旋转轴将功率从一处传至另一处。 万维网是一个独特的通讯和出版媒体。 第2节 翻译练习6 A practical means of transferring geothermal energy is to convert it to electric power. An electron, if moving, produces a magnetic field. 将地热能转变成电能是输送这种能量的一种切实可行的办法。 电子如果运动，就会产生磁场。 第2节 翻译练习7 Needle bearings have a high load capacity. Considerable effort must be expended to ensure consistent blast volume, humidity and temperature. 滚针轴承的承载能力大。 还要在确保风量、湿度和温度稳定方面做出相当大的努力。 第2节 翻译练习8 The gear teeth should have the strength sufficient to operate. We’ll do everything possible to improve the supply of electricity. We hope everything ready for the operation. Scientists have found a method of measurement suitable for most island waters and coastal areas. 齿轮的齿必须具备足够的运转强度。 我们将尽一切努力来改善电力供应。 我们希望一切在开工之前就绪。 科学家们已经找到了一种适合大多数岛屿的近海和沿海地区的测量方法。 Coal is a kind of fuel suitable for power generation. The only transformer available is produced in Shanghai. 煤是一种适合发电的燃料。 唯一可用的变压器是上海产的。 第2节 翻译练习9 The resistance of the load is too high for the amplifier. For this reason the switching signal should be no steeper or larger than necessary. The capacity to store water in their leaves is typical of desert plant. He is quite familiar with state function. 负载的电阻对于放大器来说太高。 因此激励信号的斜率及宽度不应超过所要求的数值。 在叶子中储存水的能力是沙漠植物的特性。 他非常熟悉状态函数。 第3节 翻译练习1 Deserted soils are sparsely covered with shrubs and grass. The relationships used are briefly outlined. 荒漠上稀疏地覆盖着灌木丛和杂草。 这些用到了的关系已简要地概括出来了。 5.3 副词的译法 第3节 翻译练习2 The resulting flux is confined essentially to the ring. Actually, and metal or alloy can be cast by precision casting. Normally the whole mass of the atom is concentrated in the nucleus. 所产生的磁通基本上被限制在环内。 实际上，任何金属或合金都可以进行精密铸造。 在正常情况下，原子的整个质量都集中在原子核里。 第3节 翻译练习3 Admittedly, the term temporal coherence seems to imply an effect which is exclusively temporal. The most important advantages of rolling bearings over sliding bearings is the most complete elimination of friction. 不可否认，时间相干性这个术语似乎意味着一种只属于时间的效应。 滚动轴承优于滑动轴承的最重要的优点在于几乎完全消除了摩擦。 第3节 翻译练习4 We are certain that neutrons act differently from protons. To detect gases, a sample of air can be analyzed chemically. Slopes orientated differently receive direct solar radiation in different amounts. 我们确信中子的作用和质子的是不同的。 为了检测各种气体，可以对空气试样进行化学分析。 朝向不相同的山坡，直接接收到的太阳辐射量是不同的。 第3节 翻译练习5 The salts should be heated electrically, if possible. The methods of controlling pests chemically often have undesirable side effects; for this reason it is likely that the methods of controlling biologically will be applied increasingly in the future. Evaporation takes place only at the surface of a liquid; boiling takes place throughout the liquid. 如果可能的话，这些盐应该用电来加热。 用化学品控制害虫的方法常有不良的副作用，因此将来会越来越多地采用生物学方法。 蒸发只是发生在液体表面，沸腾发生在液体各处。 第3节 翻译练习6 The CPU also controls the flow of data to and from the peripheral devices. It is also possible to check the temperature distribution at the top of the burden, although the burden at the top of the furnace is not evenly distributed. There is also an increased excretion of nitrogen, inorganic phosphorus, and sodium chloride (salt). CPU还控制着流向和来自外部设备的数据流。 尽管炉顶炉料的分布方式是不均匀的，但炉顶炉料的温度分布也还是可以检测的。 推拿还促进氮、无机磷和氯化钠（盐）的排放。 第3节 翻译练习7 A relatively small explosion would be enough to send a ship off at a very fast rate. When the core of this cloud became dense enough, gravity triggered the collapse of its inner layers. Satellites--- some large enough to be planets in their own right--- either formed along with the giants or were captured later. 一次较小的爆炸就足以将飞船以极快的速度发射出去。 当这个分子团的核心变得十分稠密时，重力引起分子团的内层崩溃。 至于卫星，有些大的足以称得上行星，它们或是与这些巨大的行星同时形成，或是后来被猎获的。 第3节 翻译练习8 The watt is a small unit of power, so we use the kilowatt instead. Instead of working with the space variable for electric field intensity we can work directly with voltage. 瓦特是一个很小的功率单位，因此我们就改用千瓦代之。 我们可以直接用电压来代替电场强度这个空间变量。 第3节 翻译练习9 The experimental result was just the opposite of what I had expected. The introduction of laser into industry has only just begun. 实验结果与我预料的刚好相反。 激光用于工业还仅仅刚开始。 第3节 翻译练习10 Never lay tools or workpieces on the ways of a lathe. Man has never made a machine that, of itself, will continue in a state of uniform motion. Up to now, atomic energy has never been used for aircraft propulsion. 绝不要把工具或工件放在车床的导轨上。 人类从未制成过一台能自行永久保持匀速运动状态的机器。 到目前为止，原子能从来没有被用于飞机的推进。 第3节 翻译练习11 An electric current is only a shifting of electricity. What we call mass is only another manifestation of energy. Only when an object moves, is work done. 电流仅仅是电的移动。 我们所说的质量只是能的另一种表现形式。 物体只有移动时才做功。 第3节 翻译练习12 Gravity keeps the satellite in orbit. Otherwise, it would drift off into space. His inspection of the transmission lines revealed some possible faults that might otherwise have been overlooked. 引力使卫星保持在轨道上，否则卫星就会偏离而进入太空。 他对输电线路进行检查，查出了一些故障，否则这些潜在的故障就会被忽视。 第3节 翻译练习13 In a mathematical sense the impulse response is a rather sophisticated concept. Process depends on identifying radio stars with some kind of object emitting visible light--- but radio astronomers can give their optical colleagues only rather imprecise directions as to where to look. The operation of our generating unit was no better but rather worse. 从数学意义上讲，冲量反应是个相当微妙的概念。 进一步的进展取决于能否确定射电星是一种能发射可见光的天体，然而射电天文学家只能给光学天文学家提供很不精确的观测方向。 我们机组运行的情况没有见好，相反更糟了。 The temperature did not go up, as one had expected, but rather went down. They are encouraged in designing a turbine rather than repairing it. In deciding where an airplane actually is in the sky, we believe our eyes rather than our ears. 温度没有像人们预料的那样上升，反而下降了。 他们从事涡轮机的设计工作，而不是修理涡轮机。 要判断飞机在空中的确切位置，我们与其相信自己的耳朵不如相信自己的眼睛。 第3节 翻译练习14 Just as the feed-water supply system can be controlled, so the coal handling equipment can also be computer-controlled. It is for this reason that so much care has to be given to the burden preparation by sintering and by the blending of fluxes and coke. So many devices have utilized these processes. 正如给水系统可由计算机控制那样，输煤设备也可以这样做。 正因为如此，必须通过优良烧结以及助熔剂和焦炭来精心准备高炉的炉料。 如此之多的装置现已采用了这些工艺。 第3节 翻译练习15 Attention is given to the transformer, too. Too many women ignore the amount of iron they take in. Such particles are far too tiny to be seen with the strongest microscope. Hardened steel is too hard and too brittle for many tools. 同时也注意变压器。 太多的女性忽视了自己摄入的铁离子含量。 这种粒子太小，即使用最高倍的显微镜也看不见。 硬化钢太硬、太脆，对许多工具的制作都不适宜。 第3节 翻译练习16 Many natural phenomena yet remain to be investigated. The cause of this wear have not yet been established. If the temperature is high, the resistance of a wire becomes yet greater. 尚有许多自然现象有待研究。 这种磨损的原因尚未查明。 如果温度升高，导线的电阻会更大。 This could turn out to be our biggest mistake yet. This is the biggest underground lake yet discovered. 这是我们到目前为止所犯的最大错误。 这是迄今已发现的最大的底下湖。 5.4 形容词和副词比较级的译法 第4节 翻译练习1 The roads in our power plant are with a new kind of material, the strength of which is as great as that of concrete. Metals do not change their form as easily as plastic bodies do. 我们电厂的道路是一种新材料铺设的，这种新材料的强度与水泥的强度一样高。 金属不像塑料物体那样容易变形。 第4节 翻译练习2 This material can withstand higher stresses under repeated loading. Given a higher capital cost for electric buses, the cash grant payable would be higher for a conventional vehicle. If one has an attitude of respect for the equipment, the end product will be more satisfactory. 这种材料在交变载荷下可以承受较高的应力。 即使电瓶巴士投资成本高于传统车辆，传统车辆应支付的现金补贴也会更高。 如果人们对生产设备持尊重态度，那么其生产出的成品也会更加令人满意。 第4节 翻译练习3 The right genetic material, weight for weight, can be more valuable than precious metals and jewels. Three of the giant planets radiate more heat back into space than they absorb from the sun. 恰当的遗传物质，就其重要性来说，要比贵金属和珠宝更有价值。 巨大的外层行星中有三颗射向太空的热量超过它们从太阳那里吸收的能量。 第4节 翻译练习4 Even quite small amounts of some impurities can make copper a much poorer conductor of electricity. Aluminum and copper are far more corrosion-resistant than ordinary steel. 甚至很少量的杂质都可能会使铜成为性能差得多的导电体。 铝和铜的抗腐蚀能力比普通钢高得多。 第4节 翻译练习5 Nuclear energy is being used more and more widely. More and more nuclear power stations are built up. 核能用得越来越广泛了。 建设了越来越多的核电站。 第4节 翻译练习6 The greater the bearing load, the shorter will be the life of the bearing in revolutions. The farther out the line of the momentum extends, the greater the angular momentum. The greater the cross-sectional area, the greater the strength will be. 轴承的载荷越大，其以转数为单位的寿命就越短。 动量作用线伸展得越远，角动量就越大。 截面越大，强度越大。 5.5 形容词和副词最高级的译法 第5节 翻译练习1: Polyacetylene is the simplest possible conjugated polymer. Pain is the most prominent symptom of surgical disease. 聚乙炔可能是最简单的共轭聚合物。 疼痛是外科疾病最突出的症状。 第5章 总复习题 This seems to indicate that further research would be necessary. An a.c. motor is similar in construction to a d.c. motor. Natural environment can be easily ruined by inappropriate exploration. Negative charges are moving counterclockwise. 这似乎表明进一步研究的必要性。 交流电动机与直流电动机结构相似。 开发不当容易毁坏自然资源。 负电荷按逆时针方向流动。 The average value of voltage can be measured point by point. The problem of materials is eased by the lower boiling point. As a result, although there is minimal friction present, a lubricant is still absolutely essential. Removal procedure for left-hand and right-hand cyclic cylinders is essentially the same. 因此，虽然有很小的摩擦，但润滑剂仍旧是非常必要的。 电压的平均值可以逐点测量。 由于沸点较低，材料问题容易解决。 左右两边循环气缸的拆卸步骤基本上相同。 Substantially, anthecyanin, the pigment that turns leaves--- and apples--- red, is produced by sugars that remain after the nutrients are choked off. Massage will affect muscles throughout the body. In this test the major part is backed off electrically. It is also good for shock and impact loads. The term minimum life is also used to mean rating life. 在此项实验中，主要部分被电补偿。 本质上，使树叶和苹果变红的色素——花色素苷是营养去除后剩余的糖分产生的。 它还适用于振动和冲击载荷。 推拿将会对全身的肌肉组织产生影响。 最小寿命这个术语也指额定寿命。 Usually, a 2cm adjustment of the machine is enough to bring the pressure back to normal. Statistics is a rather modern branch of mathematics. Computers provide the means for greater speed and accuracy in working with ideas than had previously been possible. Less than a quarter of the energy of a human engine is converted into mechanical energy. Hydrogen is the lightest gas, its density being 0.0894 g/l. 统计学是一门相当新的数学分支。 人体发出的不到1/4的能量转变为机械能。 计算机处理意念时所提供方法的速度和精确度都超过了以往所能达到的水平。 氢是最轻的气体，其密度为0.0894克/升。 通常，把机器调整2厘米就足以使压力恢复正常。 6.1 介词的一般译法 第1节 翻译练习1 In general, man serves as the source of infection while animals act as such only occasionally. An industrial robot shares many attributes in common with a numerical control machine tool. 一般来说，人可作为感染源，而动物只是偶然如此。 工业用机器人与数控机床有许多共同的特性。 第1节 翻译练习2 With non-changeover control both the boiler plant and the chiller plant operate to provide simultaneous heating and cooling throughout the year. The online service delivers substantially more value to our global audience of e-business professionals in the chemical, plastics and allied industries. This device can mimic photosynthesis to produce usable energy from sunlight. 采用非转换控制，锅炉设备和制冷装置都在运行，全年可同时供暖和制冷。 该网络服务主要向全球从事化学、塑料及相关工业的专业电子商务用户提供更有价值的服务。 这种装置能够模拟光合作用，利用阳光产生可用的能源。 第1节 翻译练习3 The longitudinal axis of the turbine generator is perpendicular to the axis of the steam generator. In the right conditions, membranes are self-assembling. Winding of the spring induces residual stresses through bending. 汽轮发电机的纵轴与锅炉轴线垂直。 当条件适宜时，细胞膜会自行聚集。 卷绕弹簧时因为弯曲引起了残余应力。 第1节 翻译练习4 If leakage occurs around output shaft, replace seal and packing. So they give off a stronger signal to sensitive radiation detectors mounted over the subject’s head. 如输出轴周围漏油，应更换密封件及填料。 因而它向安装在受试者头部上方的灵敏的辐射探测器发出的信号比较强。 第1节 翻译练习5 It is customary to use electromagnets rather than permanent magnets for the field. This flat screen technology eliminates curvature on the screen surface. All the charge on a conductor lies on its surface. 通常磁场用的都是电磁铁而不是永久磁铁。 这种纯平面技术可以消除屏幕表面的弯曲。 导体的全部电荷都在其表面。 6.2 介词短语的译法 第2节 翻译练习1 For ease of assembly and removal of the wheels, the outer races are press-fitted in the wheel hubs. With the length much greater than its width, the coil is called solenoid. With only about half as many moving parts as a conventional engine, a Wankel is only half the size and weight, and almost completely vibrationless. 为了便于车轮安装和拆卸，把外套圈压入配合到轮毂里。 如果长度远远超过了宽度，这种线圈就称为螺线管。 由于其运动机件数几乎仅为一般发动机的一半，汪克尔发动机只有一般发动机的一半大、一半重，而且几乎完全没有振动。 Without an electric field applied, a dielectric atom is symmetrical. Despite changes in the load, the voltage applied to it remains fairly constant. For more information on the improvements we’ve made, scroll down to New Features & Functionality. 如果没有外加电场，电介质原子是对称的。 不管负载如何变化，加在负载上的电压都仍然相当稳定。 要想对我们的改进有更多的了解，请往下看“新特点与新功能”。 第2节 翻译练习2 Singularity functions do not occur in physical systems. A fair amount of theoretical and experimental work has been devoted at this agency to a better understanding of non-stationary aerodynmics. 物理系统不存在奇异函数。 该机构为更好地了解非定常气体动力学作了大量的理论研究和试验工作。 第2节 翻译练习3 Animals are always losing carbon by respiration as against plants always gaining carbon. The most effective method of reducing friction is to use rolling friction instead of sliding friction. 动物通过呼吸排除碳，而植物却吸收碳。 减少摩擦力的最有效的方法是采用滚动摩擦，而不是采用滑动摩擦。 第2节 翻译练习4 The shape of the electron spectrum in beta decay is not dominated by properties of the matrix element. Pressure in a liquid is at right angles to the walls of container. β衰变的电子谱的形状不取决于矩阵元的性质。 液体的压力与容器壁垂直。 第2节 翻译练习5 Hysteresis energy is a useful basis for the establishment of failure criteria in fatigue. Physical chemistry applies the methods of physics to the study of chemical systems. 在建立疲劳破坏准则时，迟滞能量是一个有用的依据。 物理化学是应用物理学的方法研究化学体系。 6.3 常用介词的译法 第3节 翻译练习1 Little information is given about the origin of life. A basic change in thinking about force and mass is required. Fluoride damage is generally restricted to areas about manufacturing plants. The vacuum was created about the exit. 关于生命起源方面的资料极少。 对于力和质量的看法需要做根本的改变。 氟化物的危害一般仅限于制造厂附近。 在出口附近产生真空。 第3节 翻译练习2 All of its circuit elements are bonded together after being manufactured. Line reams new bushings after installation. After all logic events have been completed, the automatic control unit initiates the machine after the instruction. 将所有的电路元件在制成之后都连结在一起。 安装后对新轴套绞同心孔。 在所有的逻辑事件完成之后，自动控制器按照指令再次启动该机器。 Those machines are made after the model. After all its changeable forms, energy can never be destroyed. 那些机器是按该模型制成的。 尽管能的形式是可以改变的，但绝不会消失。 第3节 翻译练习3 Working instruments are verified for calibration against reference instruments. The current in a transmitting antenna when plotted against time is usually a sine wave. The process was against any basic laws of physics. Force is necessary to drive an electric current against a resistance. 工业用的仪表要根据基准仪表来校验其刻度。 将发射天线中的电流相对于时间来描述出来，常是一正弦波。 该过程违背了物理学的基本原理。 驱动电流克服电阻需要有电动势。 One of the chief uses of zinc is to protect the surface of iron against rust. Lightening rods are used to protect electrical devices against lightening. It is necessary to prevent induction motors against overload and undervoltage. The advantages and disadvantages of each algorithm have to be weighted against each other in the light of the particular application. 锌的主要用途之一是防止铁表面生锈。 避雷针用来保护电器设备不受雷击。 必须保护感应电动机，防止过载及欠压。 每一种算法都必须根据具体应用相互对比才能权衡其优劣。 第3节 翻译练习4 The second phase of the restoration project will be to lay down a stabilization ring around the tower’s foundation. The separating force on the mill was calculated to be around 10 million 1b. The arch dam is economical in narrow canyons where the top chord length is around two to three times the height of the dam. 修复工程的第二阶段是在塔基周围建造一环形稳固基。 此轧机的轧制力量估计大约一千万磅左右。 截面越大，强度越大。 第3节 翻译练习5 Each observation could be weighted inversely as the distance or as the square root of the frequency. If the electric lines are parallel to the earth, the wave is referred to as horizontally polarized. 每次观测可以倒过来加权，作为距离或频率的平方根。 如果电力线与地面平行，其电波就称为水平极化电波。 第3节 翻译练习6 At the beginning of its operation, this turbine is only about 50 percent efficient. It is usual to provide a flowmeter at the column outlet. A small hole is provided at the lock ring groove to facilitate removal of the lock ring. 在开始运行的时候，这台涡轮机的效率只有50%。 在柱子出口处常常要安装一个流量器。 为使锁定环拆卸方便，可在其沟槽内开一小孔。 The shunt motor operates nearly at constant speed. Women of child-bearing age are at greatest risk, since their monthly bleeding is a major source of iron loss. 并励电动机差不多恒速运行。 育龄女性危险最大，因为月经是铁流失重要原因之一。 第3节 翻译练习7 And offshore drilling is made possible by using huge quantities of gaseous nitrogen and oxygen to provide a livable atmosphere deep under water. Every metal possesses certain properties, or characteristics or qualities which we can find by experiment. All materials are deformed to some extent by the application of an external force. 用大量的氮气和氧气形成在深水中能够生活的环境，才有可能进行海底石油钻探。 每一种金属都具有某些性能，或特性、性质，而这些我们可以通过实验检验出来。 所有材料多少都会由于外力而变形。（练习8用法） Nd By the Law of Universal Gravitation, all bodies attract each other. By this theory we can explain the phenomenon for which the old view of matter did not account. 按照万有引力定律，一切物体都相互吸引。 根据这一学说，我们就能解释旧的物质观没有说明的现象。 第3节 翻译练习8 The machine tool is directly driven by the main drive motor. The pituitary gland is constituted by two lobes. The energy possessed by an object by virtue of its motion is called kinetic energy, or energy of motion. The production capacity has greatly increased by the development of the control of manufacturing processes by computers. 机床由主电机直接启动。 物体由于运动而获得的能量称为动能，或称为运动能量。 由于采用了计算机控制制造过程，因而生产能力大大提高。 垂腺体由两个叶组成。 第3节 翻译练习9 We may not have eliminated cigarette smoking completely by the end of this century. The faculty line must be repaired by the time of the summer harvest. The current in an inductor lags the voltage by 90° or, what is the same thing, the voltage leads the current by 90 °. The experts calculate that this will straighten up the tower by several centimeters. 到本世纪末我们或许还不能完全消除吸烟现象。 夏收之前，故障线路必须修好。 根据专家们的计算，这将使斜塔取直几厘米。 电感器中的电流落后于电压90°，或者说，电压超前于电流90 ° 。 第3节 翻译练习10 By hPa we mean an international standardized pressure unit. By conductivity we mean the ability to conduct an electric current. 所谓百帕，是国际上通用的表示气压的单位。 所谓导电率，是指传导电流的能力。 Nd 第3节 翻译练习11 The electric drive system is made detachable for ease of transportation and installation. CFCs and other ozone-depleting chemicals were first mass-produced in the 1950s for use as refrigerants, industrial solvents, cleaning fluids and agents in making foam products. These data are the basis for important decisions. They will build two power plants here, which can meet the demands for power supply. 为了便于运输和安装，电力驱动系统做成可拆式。 20世纪50年代，氟里昂和其他消耗臭氧的化工产品首次批量生产，它们主要用作制冷剂、工业溶剂、清洗液以及制造泡沫产品的制剂。 这些数据上做出重要决策的依据。 他们将在这里建两座电厂，这样便可以满足对电力的需求。 Nd 第3节 翻译练习12 The temperature was too high for the boiler to withstand. A visual inspection must be done carefully for the materials, especially for those to be used in fabrication of pressure vessels. For this reason, be very careful when you take antibiotics. The first passengers came to ground, none the worse for their experience, 3,000 meters from their standing point. 温度提高，致使锅炉承受不了。 必须对材料仔细进行外观检查，对制造压力容器所用材料尤需如此。 由于这个原因，当你用抗生素时务必非常小心。 第一批乘客在离出发点3000米处着陆，并没有因这一 遭遇而发生不良反应。 Nd 第3节 翻译练习13 Make water do duty for alcohol as a solvent. They succeeded in substituting a synthetic rubber for the natural rubber. Electricity compensates for barometric pressure as well as system pressure variations. 用水代替酒精当溶剂用。 他们在用合成橡胶代替天然橡胶方面取得了成功。 用电补偿大气压力和系统压力的变化。 Nd The disease raged through the city for months. The mixture was cured at room temperature for 8-14 days. 这种疾病在这座城市猖獗了几个月。 混合物在室温下需熟化8-14天。 第3节 翻译练习14 For all their great stableness under ordinary circumstances, insulating materials may change radically in characteristics under extreme conditions of voltage stress or temperature or under the action of certain chemicals. For all its invisible shield, the ozone layer can be measured in a number of ways. For all our advice, he insists on carrying out ignition experiment. 尽管在正常的情形下绝缘材料的性能很稳定，但在极端情况下，比如电压过高、高温或在某种化学物质作用下，绝缘材料的性能会遭到完全破坏。 尽管臭氧层是一种不可见的保护层，但还是有多种测量它的方法。 尽管我们劝阻他，他仍然坚持要进行点火实验。 Nd 第3节 翻译练习15 This reduces the resistance to current flowing from the wire through the rubber to copper strips below the tubes. A user may jump from one document to another in a nonlinear, associative way. From the information in this table, we can easily compute an estimate of the value of the mean of this grouped data. Having no compass, he got his bearings from the sun. 轴承的载荷越大，其以转数为单位的寿命就越短。 动量作用线伸展得越远，角动量就越大。 截面越大，强度越大。 Nd 第3节 翻译练习16 Fabricate a shield from 12cm aluminum alloy to the dimensions shown on Figure 11. The electronic device is made from semiconductor. Dead time is the time a worker losses from lack of materials or equipment breakdown. A similar error arises from neglect of multiple causes. 按图11所示，用12厘米厚的铝合金制造防护罩。 这只电子器件是用半导体做的。 无效时间是指工人因无原料或设备故障而失去的时间。 类似的错误可能由于忽视了多种原因而产生。 Nd 第3节 翻译练习17 The hardened washer shall be prevented from turning during locknut tightening. Washers shall be from burrs and sharp edges. The triggering circuit is immune from noise. The mixture are distinct from compounds. Data is often distinguished from information and from programs. 当自锁螺母拧紧时应防止淬火垫圈转动。 这个触发电路不受杂音影响。 混合物不同于化合物。 垫圈不应带有毛刺和尖角。 数据通常有别于信息和程序。 Nd 第3节 翻译练习18 Highly poisonous insecticides should be kept from ordinary insecticides. Electrolysis is the liberation of free elements from a liquid by passing an electric current through it. Place these parts in a plastic bag, and keep separate from other bearing assemblies. 剧毒农药和普通农药要严格分开置放。 电解就是让电流通过液体，从而使游离元素从液体中分离出来的过程。 将这些零件装进塑料袋中，和其他轴承部件分开置放。 Nd 第3节 翻译练习19 Canadian scientists looked for ozone thinning in the Arctic. In Canada, governments are also starting programs to recycle and recover CFCs. The uses of industrial gases in our high-tech world are numerous and varied. 加拿大科学家在北极区寻找臭氧层变薄的迹象。 在加拿大，政府正在开展工作回收和循环使用氟里昂。 在我们这个技术高度发达的社会中工业气体的用途是多种多样的。 Nd The hummingbird has the highest metabolic rate per unit of body weight in the avian world. Although in recent years the liquid state has been the subject of intense study, the several books treat mainly the physics of this state. In the 1970s, the focus of designing hardware was the creation of circuitry. 在鸟类世界中，单位体重的新陈代谢以蜂鸟为最高。 虽然近年来液态已成为努力研究的课题，但是这些书主要是谈论液态的物理特征。 在20世纪70年代，硬件设计的焦点是生成电路。 第3节 翻译练习20 The decision to repair is not easy, especially in borderline cases. All molecules are in constant motion. In the study of lubrication and journal bearings, additional fundamental knowledge must be utilized. In order to prevent any damage or injury to human eyes in training, a laser energy attenuator may be mounted on the laser exit window. 做出返修的决定不是容易的，在可修可不修的情况下尤其如此。 在研究润滑和滑动轴承时，尚需用到另外的基础知识。 在训练时，为防止误伤人眼，可在激光输出窗口上装上激光能量衰减器。 一切分子都处在永恒的运动状态之中。 Nd 第3节 翻译练习21 The electric power which is consumed in an electric circuit is measured in watts or kilowatts. Energy and work are both measured in joules. Power, being the amount of work done per second, is measured in watts (joules/sec). 电路中消耗的电力是以瓦或千瓦计量的。 能和功都用焦耳计量。功率是每秒钟所做的功，所以用瓦特（焦耳/秒）计量。 Nd 第3节 翻译练习22 Objects sink down into fluids until the upthrust equals the weight of the object. If a permanent magnets is plunged into the coil the meter registers a momentary current. It is only recently that astronomers have begun specific research into black holes. 物体沉入流体，直到向上的推力与物体的重量相等。 如果把永久磁铁插入线圈，电表会记录到一次瞬间电流。 只是在最近，天文学家才开始对黑洞进行具体的研究。 Nd Physics gives us power to adventure into the unknown. Heat transforms ice into water and water into steam. The process converts iron and steel scraps into metal powder. 物理学给予我们探索未知世界的能力。 热使冰变成水，使水变成蒸汽。 此法可把钢铁切屑变成金属粉末。 第3节 翻译练习23 Considerable literature has grown up relating to experimental confirmation of elastohydrodynamic theory. The successful launching of space rockets has added much to man’s knowledge of the upper strata of the atmosphere. The processor is in over-all control of the system. 关于弹性流体动力润滑理论的实验证明，已涌现出大量文献。 宇宙火箭发射的成功大大增加了人类对大气上层的知识。 处理器对系统实施全面控制。 Nd 第3节 翻译练习24 These compounds are of the same family of organic materials. All the types of memory we have discussed are of “random access”. It might be thought that these two effects would be of the same order of magnitude. Today of the four only Earth is known to be tectonically active. 这些化合物属于同族有机物。 上述的各类储存期都属于“随机存取”类型。 人们可能会以为这两个效力的大小属于同一个数量级。 今天，在这四颗行星中，据人们所知只有地球的地壳构造仍在活动。 Nd Of all forms of energy electricity is the most important. 在所有形式的能量中，电能是最重要的。 第3节 翻译练习25 A magnetic system is made of wrought iron arranged as in Fig. 8-16. Flat belts are usually made of either oak-tanned leather or a fabric, such as cotton or rayon, which has been impregnated with rubber. The motor consists of two parts, the stator and the rotor. 磁系统是由熟铁制成，如图8-16所示。 平型带通常用橡树皮鞣革或浸渍过橡胶的棉织品或人造纤维织品制成。 电动机由定子和转子两部分构成。 Nd Each stage requires a different set of tools and sometimes requires different equipment and skills. 每一步都要求有一套不同的工具，有时还要求有不同的设备和技术。 第3节 翻译练习26 This chart may be plotted on semilog paper or on log-log paper. Apply a small amount of the adhesive liquid on the face of the gasket. Final composition of the Theater List is normally decided by the surgeon on the day prior to operation. On freezing, water does not contract, but instead it expands. 此曲线图可绘于半对数图纸或对数图纸上。 在密封垫表面上涂少许粘着剂。 接受手术人员的最后名单一般由外科大夫在手术前一天做出决定。 水结冰时，并不收缩，而是膨胀。 Nd 第3节 翻译练习27 Further research on this subject may suggest ways in which earthquakes can be predicted and prevented. A good example of the local effects of pollution on weather is the increase in rainfall found in regions adjacent to a large paper mill. The design of structures and drainage systems are not based on these adverse site conditions. 在这方面作进一步研究也许能提供预报和预防地震的方法。 污染对天气有局部影响，一个很好的实例就是在大型造纸厂附近地区降雨量有所增加。 工厂的建筑物和排水系统没有根据这些不利的厂址条件进行设计。 Relationships between voltages and currents in a circuit have been established on the experiments. On Bohr atomic theory and wave amplification theory, laser has been developed by scientists. 电路中电压与电流的关系已根据实验确定。 根据玻尔的原子理论以及波的放大理论，科学家们研制了激光。 第3节 翻译练习28 It relies heavily on digital processing. On these observations, a hypothesis may be formulated. The motor is on the operation. He developed pneumonia caused by blood clots in the lungs after traveling to Asia on an economy-class ticket. 这在很大程度上要依靠数字处理。 电动机在运行。 他在一次乘经济舱飞往亚洲之后，由于肺里产生血块而得了肺炎。 通过这些观察，可以作出一个假设。 Nd 第3节 翻译练习29 The prereduced or raw fine ore is injected into the smelting reduction furnace through the upper tuyeres. Gases readily diffuse through porous solids. The radiation could penetrate through layers of different materials. 经过预还原的矿粉或者原始的矿粉都是通过上部的风口送入熔融还原炉的。 气体很容易通过多孔固体渗出。 该辐射可以穿透多层不同的材料。 Through the combustion of the fuel, chemical energy is converted into heat energy. The range and variety of work that can be done on a lathe are greatly increased through the use of various work-holding attachments. Atomic energy has arrived in time to save civilization from dying through lack of power. Silicon, chiefly through its better temperature characteristics, quickly replaced germanium in the power diode. 通过使用各种工件夹具，可大大扩大车床所进行的作业范围和种类。 由于硅有较好的温度特性，在功率二极管中，硅很快取代了锗。 通过燃料的燃烧，化学能转变为热能。 原子能已及时出现，从而拯救文明使其免于因能源短缺而灭亡。 第3节 翻译练习30 Magmas in transit to the surface will further supplement this heat. The makeup water pipeline conveys the makeup water from the makeup water intake structure to the cooling tower basin. A fresh cutter can be loaded to the spindle in a similar manner. 向地表移动的岩浆进一步补偿这种热量。 补给水管道把补给水从取水建筑物输送到冷却塔水池。 用同样的方法可将新刀具装在主轴上。 The function of the computer is not limited to providing support in solving mathematical problems. The system is restricted to examining the surface only. Needed is a method of timing accurate to millionths of a second. Cultivation can be mechanized to the largest degree. 该系统仅限于检验金属表面。 耕作可在最大程度上实行机械化。 计算机的作用不能只限于帮助解决数学问题上。 需要有一种精确度达到几百万分之一秒的计时方法。 第3节 翻译练习31 Computers have as yet contributed little to pure mathematical theory. Air pressure is inversely proportional to altitude. Thus, Fig. 5 is similar to Fig. 4b insofar as the same recombination and filters have been applied to both. An electric motor is similar to a generator in construction. 迄今为止，计算机对纯数学理论的贡献不大。 气压与高度成反比。 电动机和发电机在结构上类似。 第3节 翻译练习32 Water enters the cylinder and fills the space under the piston. When a vehicle passes over a road, its weight is transmitted through the wheel on to the pavement under it. But how can bouncing sound waves help oceanographers to see the sea floor and the mud, soil, and rocks under it? 水进入泵筒，并注满活塞下面的空间。 当一辆车驶过马路时，其重量通过车轮传至车下的路面上。 而反射波怎样帮助海洋学家去考察海底以及下面的泥、土和岩石呢？ Under certain conditions, heat energy may be changed into mechanical energy, and mechanical energy (may be changed) into heat energy. There is no material but will deform more or less under the action of forces. Water vapor in the air breaks down under the intense heat. 在力的作用下，一切材料无不变形。 在一定条件下，热能可以转换成机械能，机械能也可以转换成热能。 空气中的水蒸气在高温下发生分解。 第3节 翻译练习33 Under some trade terms, the buyer might undertake to clear the goods for export in the seller’s country. The books are categorized under the Dewey Decimal System. The agreement for the trade and cooperation is still under a draft. Lianyungang Nuclear Power Station is still under construction. 根据某些贸易条款规定，买方须负责在卖方所在国的出口清关。 这些图书是按照杜威十进制编目的。 贸易合作的协定仍在草拟中。 连云港核电站仍在建设中。 第3节 翻译练习34 It has no connection with the automatic positioning facilities. Oxygen is a gas that can unite with many substances. The resistance usually varies with temperature. 它与自动定位装置没有关系。 氧是一种能与许多物质化合的气体。 电阻常常随温度变化。 With the invention of the transistor, electronics entered a new phase. With the advance of science and technology, some scientific problems become less complicated than they were thought. 随着晶体管的发明，电子技术进入了一个新的阶段。 随着科技进步，有些科学问题没有原先认为的那么复杂了。 第3节 翻译练习35 The machining center is provided with an automatic tool changer. Bricks are also produced in many different colors and with various finishes. Most of the machining we do in a machine shop is done with cutting tools. Unix marketers have looked with some envy at these applications. 加工中心备有自动换刀装置。 砖也可以烧成不同的颜色，具有不同的光洁度。 我们在机械加工车间所做的大部分机加工是用刀具来进行的。 “UNIX”的销售者以很大的热情关注着这些应用程序。 第3节 翻译练习36 With the advent of modern methods of communication the whole world has been transformed into a single mechanism. The machines may get heated with overload. Computers perform particular operations with the information they are given. 由于近代通信方法的出现，整个世界已转变为一个统一的机体。 机器可因过载而发热。 计算机根据所收到的信息进行特定的运算。 Assemble bearing inner and outer races with serial numbers indexed. An interrupt is allowed to occur in accordance with specified priorities. 根据特定的优先权允许发生中断。 根据序号组装轴承内外座圈。 第3节 翻译练习37 With its many advantages, wood is not without its drawbacks as a fuel. With its complex structure, it is liable to install. With no discovery, many laws of nature actually exist in nature. With slight repair, the old type of engine can be used. 尽管木材有许多优点，但作为燃料仍有缺陷。 虽然结构复杂，但容易安装。 许多自然规律虽然尚未被发现，但它们确实存在于自然界之中。 只要稍加修理，这台老式发动机就可使用。 第3节 翻译练习38 Petrol is a mixture of the lower-boiling hydrocarbons, with boiling temperatures ranging from 100°C to 400°C. Never operate the engine with the water temperature in the radiator exceeding 100°C. The field-effect transistor consists of a single crystal of doped semiconductor material in the shape of a bar with leads connected to both ends. 在散热器中的水温超过100°C的情况下决不要开发动机。 场效应晶体管是一个棒状的掺杂半导体材料的单晶，两端连有引出线。 汽油是低沸点的碳氢化合物混合体，其沸点范围在100°C to 400°C之间。 With the cause of the fault removed at once, the generator kept working. One kind of switch is inside a metal box called a switch box, with a handle on the outside. The pressure of a gas varies inversely as its volume, with temperature constant. With the switch open, there is no current flowing in the load. 有一种开关是放在一个称作开关箱的金属箱内，而柄留在外面。 由于即使排除了故障，发电机继续工作。 温度不变时，气体压强和体积成反比。 打开开关，没有电流通过负载。 第3节 翻译练习39 Magnetic induction can take place without contact between the magnet and the iron. Without dust, there would be no clouds and no rain. Thin plates are joined by melting their edges together without the addition of filling metal. 磁铁和铁块相互不接触便可发生磁感应。 若没有灰尘，就不会形成云和雨。 薄钢板是靠熔化其边缘而焊接在一起的，不需要填料金属。 A body cannot be moved without having a force act upon it. He finished the stress experiment without difficulty. 他轻松地完成了这个应力实验。 若没有力作用于物体上，物体就不能移动。 第6章 总复习题 The conductivity of polyacetylene drops rapidly in contact with air. There is a brighter future for intelligent devices in the home. The scientists found that the blood vessels in the leg cannot swell. Once upon a time, bold claims were made about computers, the future and the “paperless office”. 聚乙炔一接触空气，其导电性就迅速下降。 家庭智能装置仍有着更加光明的前景。（省译） 科学家们发现腿内的血管不会肿胀。 曾几何时，有人就有关计算机、未来和“无纸化办公”做过大胆的预测。 The doctor advised against the use of the new treatment. If a good base cannot be found at a reasonable depth, then a so-called deep foundation must be provided. Magnetic lines of force cannot be seen, but we know they exist by what they do. 磁力线是看不见的，但是我们按照它们的作用即知它们的存在。 医生建议不要使用新的治疗方法。 若在合理的深度内找不到坚实的地基层，那就要采用所谓的深基础。 We may process directly with Kirchoff’s voltage law for the circuit. The proper values of a and b are determined from two conditions. Optional communications are free from electromagnetic interference. This type of discrepancy could have resulted from differences in kinetics. a和b的值由两个条件决定。 对于电路，我们可直接从克希荷夫电压定律讲起。 光电通信不受电磁的干扰。 这种差异可能是由动力的不同而造成的。 The visual image of the letters making up the word is converted into its spoken equivalent. Primitive man made weapons, tools, and utensils of copper, brass, and bronze. The longer wavelengths of radio signals pass through the atmosphere relatively undisturbed. 将组成词的各字母的视觉形象转换成该词对应的发音。 相对来说，波长较长的射电讯号通过大气时没有受到干扰。 原始人类用铜、黄铜和青铜制作成各种武器、工具和器皿。 Most hardness-testing systems employ a standard load which is applied to a ball or pyramid in contact with the material to be tested. All metals are corrodible under the proper circumstances. The design of the rocket nozzle also has much to do with the behavior of the exhaust and the resulting velocity of the vehicle itself. 多数的硬度实验系统使用一标准载荷加在与实验金属相接触的小球或棱锥上。 所有金属在一定情况下都是可腐蚀的。 火箭喷管的设计与排气的性能及飞行器本身的有效速度有很大关系。 Peripheral milling operations are usually performed on milling machines with the spindle positioned horizontally; however, they can also be performed with end mills on vertical-spindle machines. Copper and aluminum are the best conductors of electric current only after silver. From various experiments we cannot but think the theory still holds good. 周铣作业通常在带有水平定位主轴的铣床上进行，但也可以在带有端面铣刀的主轴铣床上进行。 铜和铝是仅次于银的最好的导电体。 根据各种实验，我们不得不承认这个理论依然是行之有效的。 Hydrogen is generated from zinc and sulfuric acid. The sort of fish cannot live in the temperate zone, let alone in the frigid zone. The locomotive developed some new problems on its line-test. Gases can be chemisorbed or physically absorbed on solids. 氢由锌和硫酸所产生。 这种鱼不适合在温带生活，更不必说在寒带了。 这台机车在试运行时出现了一些新问题。 气体能化学吸附或物理吸附在固体上。 Under ideal conditions the fatigue failure will consist of a spotting of the load-carrying surfaces. Oxidation implies the combination of other elements with oxygen to form compounds. 在理想条件下，疲劳失效将是承载表面的点蚀。 氧化意味着其他元素与氧形成化合物。 7.1 连词的一般译法 第1节 翻译练习1 Carbon steel contains only iron and carbon, while alloy steel contains some other alloying metals. Because this current continually reverses in direction, it is called an alternating current. Liquid and vapor phases cannot coexist in equilibrium. 碳钢只含有铁和碳，而合金钢含有一些别的合金金属。 由于这种电流不断地改变方向，故称为交流电。 液相和气相不能在平衡中并存。 第1节 翻译练习2 Some companies replace certain parts regularly, determining the effective life of a part and then replacing it just before it would wear out. The cost of making these tests is very low when it is divided by the total number of parts manufactured. 一些公司定期更换某些零部件，先推定零部件的有效寿命，以便在零部件即将磨损之前予以更换。 如果以生产零件的总数来划分，这些实验的成本会非常低。 Why use metal when you can use plastic? A brief description of how transistors are manufactured is given here. That is why surfactants are so widely used in industry. 既然能用塑料为什么你却使用金属呢？ 这里对晶体管的是生产方法作一简略叙述。 这就是在工业上广泛使用表面活性剂的原因。 第1节 翻译练习3 Sometimes it is necessary to drill to a depth of 1,000 meters or more, before water is found in sufficient quantity. It is stated that the positioning system has an accuracy of repeatability within 0.0002 inch. When short waves are sent out and meet an obstacle they are reflected. 有时必须钻到1000米或更深的深度，才能找到足够量的水。 据称，该定位系统的重复精度在0.0002英寸。 短波发送出去，遇到障碍就反射回来。 7.2 常用并列连词的译法 第2节 翻译练习1 Computers cope with negative numbers and fractions in binary arithmetic. Oxygen is chemically active and takes part in many reactions. 计算机采用二进制算法来处理负数与小数。 氧的化学性能活泼，能参与许多反应。（省译） Modern electronic computers and other devices will be made smaller by the development of LSI. Some electrical engineers design and maintain power plants, transmission lines and home and factory electrical installations. 大规模的集成电路的发展将使现代化电子计算机以及其他装置越来越小。 有些电气工程师设计和保养发电厂、输电线、以及各种家用和工业用电器设备。 第2节 翻译练习2 The induced electromotive force lags and the current leads. Like charges repel and unlike charges attract. 感应电动势滞后，而电流导前。 同性电荷相斥，异性电荷相吸。（省译） Transformers are commonly used in radio receivers and electrical communication circuits, and they are generally much smaller than those for power transmission. Analyzing the dynamics of the way a person signs his or her name, and not just how the signature looks, is one basis of a biometric verifier. 变压器通常用于无线电收音机和电信电路中，可是这些变压器一般比用于输电的变压器小得多。 分析一个人签名时书法的笔力，而不只是分析签名的字形如何，这是生物统计学核实器的一个基本点。 第2节 翻译练习3 It is important to know that different types of control circuits may be used in one control system, and a completed control loop may consist of a combination of electric, pneumatic, or hydraulic elements. 重要的是要知道，在一个控制系统中可使用不同类型的控制电路，而且一个完整的控制回路可由电力、气动或液压配合组成。 The synchronous motor is even more expensive and requires a source of d.c. excitation, as well as special synchronizing control to apply the d.c. power at the correct instant. Telephone communication is now widespread and efficient. The machine is old and heavy. 同步电动机则更贵，而且需要直接励磁电源和专门的同步控制器以便在适当的瞬间接入直流电源。 现在的电话通讯既广泛又有效。 这台机器又旧又笨重。 第2节 翻译练习4 We have to replace some of its parts and make this machine more efficient. To make the balloon descend, the “pilot” opened a valve and allowed some of the gas escape. 我们必须调换某些零件，以使这台机器效率更高。 为使气球降落，“飞行员”打开阀门，以使部分气体逸出。 Change one or more steps and we will improve the quality of the finished products. Use a transformer and we can transform power at low voltage into power at high voltage and vice versa. 若改变一个或几个步骤，我们就有可能提高成品的质量。 用了变压器，我们就可以把低电压变为高电压，也可把高电压变为低电压。 第2节 翻译练习5 Uncap openings in indicators and connect lines. Install aluminum washers nest to pump, steel washers next, and install nuts. Lead lacks tensile strength and it cannot be drawn out in the form of fine wire. 取下仪表开口处的盖子，再接上管路。 铅的张力差，因此不能制成细丝状。 紧贴泵处安上铝垫片，然后加钢垫片，再安上螺栓。 For LP turbine there is no residual axial thrust caused from blading because of the turbine’s double-flow arrangement of blading and thus no balancing piston is needed. 至于低压汽轮机，并没有残存的轴力，因为汽轮机的叶栅作双流配置，因而也无需采用平衡轮。 第2节 翻译练习6 The plan is very complicated technically, but the general idea is quite simple. Now the electrons which have been driven onto the negative plate are trying to get back to the positive plate, but cannot do so because of the e.m.f which is applied to the plates. 这一计划在技术上十分复杂，但总的想法却相当简单。 现在已被赶到负极上的电子力图返回正极，可是由于极板上施加有电动势的缘故而办不到。 There are already a number of modern vehicles which are not yet in common use, but which may become a usual means of transport in the future. 现在已有一些现代化的运载工具，它们目前尚未被普遍使用，但将来可能成为一种日常的交通工具。 第2节 翻译练习7 But that he prevented me, I might have kept the machine parts in the damp place. But that the checking up of the experimental data had taken so much time, we should have completed our work long ago. 若不是他阻止，我可能就会把那些机器零件保存在潮湿的地方。 假若检验这些实验数据不花那么多时间，我们早就完成了这项工作。 But for air, the earth would undergo extreme changes in temperature. But for the laws of motion as a basis, thousands of discoveries and inventions would have been out of the question. 要是没有空气，地球温度就会发生剧变。 如果没有运动定律作为基础，就不可能有成千上万的发现和发明。 第2节 翻译练习8 The positive and negative ions become separated or dissociated. No electric charges have been observed of smaller magnitude than the charge of protons or electrons. Foods quick-frozen in liquid nitrogen or carbon dioxide have transformed the way we eat. 正负离子彼此分解或电离。 还没有观察到比质子或电子的电量更小的电荷。 用液态氮或二氧化碳速冻的食物已改变了我们的饮食习惯。 We will start with a cubic inch of hydrogen at atmosphere pressure (or the air pressure at the earth’s surface). Scientists have shown that certain chemicals are slowly eroding the ozone layer. The main culprits are chlorofluorocarbons or CFCs. Fire is a chemical action, or an action taking place between different chemical substances. 我们从大气压力（即地球表面的空气压力）下的一立方英寸氢气开始。 科学家们已经证明，某些化工产品会慢慢破坏臭氧层。主要诱因就是氯氟甲烷，即氟里昂。 火是一种化学反应，也就是发生在不同化学物质间的一种作用。 第2节 翻译练习9 Right or wrong, his theory is the most influential. All methods, simple or complicated, are employed in the tension-test. You have to open the switch right away or else the fuse will be burned off. 无论对错，他的理论无疑是最有影响力的。 在拉伸试验中，所有方法不论简单还是复杂，都用过了。 你必须把开关立即断开，否则保险丝就会烧断。 A body must move, or no work is done. These old transformers have been used for ten or twenty years. The newly-installed generating set will be put in operation a month or so. 物体必须移动，否则就没有做功。 这些旧变压器已经使用大约一二十年了。 新机组再有一个月左右就投入运行。 第2节 翻译练习10 The central computer’s job is to run through the maps in its database as well as details on road works, weather, etc. Boiling point elevations, as well as the variation of the heat capacities and latent heats with temperature, are negligible. 中心计算机的任务是查阅储存在数据库中的地图以及修路工程、天气等详细情况。 沸点升高以及热容和潜热随温度的变化而忽略不计。 He discovered that he could send the sound of music as well as the dot-and-dash sounds of Morse Code through the coil. The physics students study chemistry as well as physics. 他发现不仅能使线圈传送莫尔斯电码的点划音，而且也能是线圈传送音乐。（倒译法） 物理系学生不仅学物理，而且要学化学。（倒译） Experimental data can be used to illustrate the application techniques as well as to demonstrate the validity of the approach. In order to get various vitamins a person should eat a diet including vegetables as well as meat. 实验数据既能用来说明应用技术，也能用来验证方法的有效性。（顺译） 为了摄取多种维生素，一个人既应该吃些素食，也该吃荤食。（顺译） 第2节 翻译练习11 When light strikes an opaque object, the light is either absorbed or reflected. The oxygen contained in the rocket is either in the liquid or in the solid form. When astronomers look at the sky, they expect to see either a star or a galaxy. 当光照在不透明的物体上时，光或是被吸引或是被反射。 火箭内储存的氧或是液态的，或是固态的。 每次天文学家观测天空，他们期望看到的不外乎是一个恒星或一个星系。 第2节 翻译练习12 There are materials which are neither good conductors nor good insulators. It is neither possible nor practical to make many parts to an exact size. Neither glass nor porcelain is a conductor. 有些材料既非良好的导体也非良好的绝缘体。 要使许多零件加工尺寸丝毫不差，既不可能，也不切实际。 玻璃和陶瓷都不是导体。 第2节 翻译练习13 Not only does air exert pressure, but it also has buoyancy. This method not only simplifies analysis but also facilitates measurements. 空气不仅产生压力，而且有浮力。 这种方法不仅简化了分析，而且也便于测量。 7.3 常用主从连接词的译法 第3节 翻译练习1 The loop oscillator frequency can be the same as, or a multiple of , the reference frequency. Because a d.c. motor is the same physical machine as a d.c. generator, its equivalent circuit is exactly the same as that of a generator except for the direction of current flow. 环路振荡器可以和参考频率相同，也可以是参考频率的倍数。 由于直流电机与直流发电机的物理结构是一样的，其等效电路除了电流方向外也与直流发电机相同。 R2, as is shown in Fig. 3, has been split in halves to enable the feedback to be applied. Under certain conditions a body can be charged, as has been said before. 如图3所示，R2被分为两半，使得反馈能够加上去。 在一定的条件下，物体能够带电，这在前面已经讲到。 第3节 翻译练习2 As current is increased, the flux builds up according to Curve 2. As you are doing the experiment, write down the observations. 当电流增大，磁通沿着曲线2增大。 在你做实验的同时，把观察到的情况记录下来。 As the 21st century approaches, complicated digital technologies and the promise of exploding bandwidth are combining to create a third kind of convergence. As particle has no extent, its position is a point. As water is a compound, it can be decomposed. As the current was trebled abruptly, the second valve burnt out. 随着21世纪的来临，复杂的数字技术与带宽不断扩大的前景相结合将会创造出第三种意义的“连通”。 由于质点没有广度，它的位置是一个点。 因为水是化合物，所以可以分解。 由于电流突然增加了两倍，第二个电子管烧坏了。 第3节 翻译练习3 Gravity, the force of the earth’s attraction, governs the atmosphere just as it governs solid objects. Some waves are reflected as a mirror reflects light. The large force is to the small force as the large area is to the small area. 引力，即地球的吸引力，正像它影响着固体那样影响着大气。 大的力与小的力之比就像大面积与小面积之比。 有些波被反射，就像镜子反射光一样。 Electron tubes are not so light in weight as semiconductor devices. The tools are machined to tolerances as close as 0.0001 inch. Modern computers can store the facts as fast as they are gathered and pour them out whenever they are needed. 电子管的重量不如半导体器件那么轻。 现代计算机能尽快地将收集到的资料储存起来，并在需要时输送出去。 工具加工的误差接近0.0001英寸。 第3节 翻译练习4 Complicated as modern machine is, it is essentially a combination of simple machines. The various losses in a machine, great as they are, do not in any way contradict the Law of Conservative of Energy. Very large as the nuclear energy supply in the interior of the star is, it is nevertheless finite. 现代化机器虽然复杂，但实质上不过是许多简单机械的组合。 虽然恒星内部的核能储量很大，但仍是有限的。 机器中的各种损耗尽管很大，但这与能量守恒定律丝毫也不矛盾。 第3节 翻译练习5 Each of the two wires carrying currents has a magnetic field, as if it were a magnet. Water also presses on the inside of the container as though it is trying to escape. 通电的两根导线每一根都有一个磁场，好像是一块磁铁。 水对容器的内壁也产生压力，似乎水力图要流出来一样。 第3节 翻译练习6 So long as we have means of producing heat can we keep a steam engine working. It is capable of keeping its shape as long as the planet keeps spinning. 只要设法产生热，就能使蒸汽机做功。 只要恒星连续不断地旋转，它就能保持自己的形状。 As far as processing power is concerned, the difference between a PC and a mainframe is closing fast. As far as the quality of transformers is concerned, the ones they produced are better. 就处理能力而言，PC机和大型机之间的差异正在迅速缩小。 就变压器的质量而言，他们生产的变压器更好。 第3节 翻译练习7 As soon as printing quality levels can be maintained and the effective life of the machine increased, a preventive maintenance program is effective. As soon as the electrons are transformed and ions formed, they are charged. The electrons create a magnetic field as soon as they begin to move. 一旦印刷质量得以保证并且机器有效使用期得以延长，经常性维修保养计划才是行之有效的。 一旦电子转移，形成离子，它们就带电了。 电子一开始运动，就产生磁场。 第3节 翻译练习8 Before you join one electric wire with another, make sure the current has been switched off. The leaves separate before the metallic board is touched. Further study is needed before the origin of the covalent bond can be considered a settle question. 在你把一根电线和另一根电线连接起来之前，务必先切断电源。 在接触金属板以前簧片分开。 需进一步深入研究，才能解决共价键的起源问题。 The direction of the current was decided before electrons were discovered. She switched on the engine before we could stop her. 电流方向确定了，电子才被发现。 我们还没来得及阻止她，她就开动了发动机。 第3节 翻译练习9 Even if one of the engines fails the plane will be able to continue its flight safely. It has undergone a chemical change since, even if cooled, it will not return to its original condition. The lathe can turn holes even if it is not a driller. 即使发动机中有一台失灵，飞机仍能安全地继续飞行。 车床尽管不是钻床，也能钻孔。 从那时起它已发生化学变化，即使加以冷却，它也不会恢复原样。 第3节 翻译练习10 If a.c. power is available, all drives requiring constant speed should use squirrel-cage induction or synchronous motors because of their ruggedness and lower cost. If the parting contacts are made of low-melting-point material such as brass or copper, the arc will go out at the first current zero as the voltage is insufficient to reestablish as cathode spot after current reversal. 因为鼠笼式感应电动机或同步电动机经久耐用且成本低，若有交流电源可用，所有需要恒速驱动的装置应使用这两种电机。 如果分段的触点采用低熔点金属（如黄铜、铜）等制作，则电弧会在第一个电流过零点熄灭，因为在电流极性变化后，没有足够的电压再次产生阴极辉光放电。 People might have avoided many accidents if ultrasonic methods had been known. If a d.c. system were to be used, the transmission loss would be very great. If there were no air, the earth would undergo extreme changes in temperature. The question is if there are other chief sources of organic materials in addition to coal and petroleum. 要是过去知道超声波法，人们当时是可以避免许多事故的。 如果没有空气，地球温度就会发生剧变。 若采用直流电力网，输电损失就会很大。 问题是除了煤和石油之外是否还有别的有机物主要来源。 第3节 翻译练习11 The current flows through a conductor in case there is a difference of potential between the ends of the conductor. Ordinary movements would be impossible in case friction were unavailable. 如果导体两端有不同电位时，电流就可以通过导体流动。 假如没有摩擦力，常见的活动都不可能进行。 第3节 翻译练习12 Once formed, the depletion region acts against further diffusion. Once the melting point is reached, the temperature will not increase any further until the melting is completed. Once an object is in motion, it will continue to move. 耗尽区一旦形成，便会阻碍进一步扩散。 一旦达到熔点，温度就不再升高，直到完全熔化。 物体一旦处于运动状态，就会继续运动下去。 第3节 翻译练习13 The pressure of a gas is inversely proportional to its volume provided its temperature is kept constant. The blast-furnace is expected to remain the world’s chief source of iron units steelmaking, provided adequate supplies of suitable coking coal remain available at competitive cost. 如果温度保持不变，则气体压力和其体积成反比。 只要有足够的焦煤且成本低，高炉仍将是世界上主要的炼铁设备。 All substances will permit the passage of some electric current, in the event that the potential difference is high enough. The magnetic effect does not represent a continuous expenditure of energy, supposing that the current is steady. 倘若电位差足够高时，所有的物质都将可能通过若干电流。 假如电流稳定的话，磁效应不再继续消耗能量。 第3节 翻译练习14 Since that time, especially since the introduction of the Bessemer process, the age of iron has turned into an age of steel. Electricity has found wide application since it was discovered. 自从那时起，特别是自从采用贝西默炼钢法以来，炼铁时代转变为炼钢时代。。 自从发现电以后，电就获得了广泛的应用。 Since planetesimals aggregated at different distances from the sun’s heat and light, the composition of the planets varies. Since the secondary winding is normally operated into a high-impedance circuit, the secondary current is quite small. 由于微星聚集的地点离太阳的热和光远近不同，行星的组成也不同。 因为次级绕组通常被输入高阻抗的电路，所以次级电流很小。 第3节 翻译练习15 Large accumulations of plant remains indicate that the deposits were formed in close proximity to land in a swamp, estuary, or delta. One condition for this is that the polymer consists of alternate single and double bonds, termed conjugated double bonds. 若是植物遗骸大量堆积，这表明沉积物是在紧靠陆地的沼泽、港湾或三角洲中形成的。（宾从） 一种情况是，这种聚合物由单双键交替构成，即所谓的共轭双键。（表从） We are all familiar with the fact that nothing in nature will either start or stop moving by itself. The pore space of soil that is thoroughly soaked with water does not have any air. This could result in the development of tiny, powerful computers that run for extended periods of time on little power. 我们都熟知这样一个事实：自然界没有一个物质会自行开始运动或自行停止运动。（同位从） 完全被水浸没的土壤，其孔隙没有丝毫空气。（定从） 这种技术可以用于开发体积微小、功能强大的计算机。而这类计算机依靠极少的电能就可以长时间地工作。（定从） 第3节 翻译练习16 Many substances such as glass and wood conduct so poorly that they may be called nonconductors or insulators. At an estimated 80 beats per second, the bee hummer’s wings move so rapidly that the naked eye cannot detect them. 诸如玻璃、木材之类的物质传导性极差，所以可称为非导体或绝缘体。（结果状从） 蜂鸟的翅膀估计每秒扇动80次，速度之快使肉眼看不到它的翅膀。（结果状从） Cables are usually laid underground so that their life may be extended. Now that we have examined several areas of natural science, perhaps it would be well to attempt to define science. Lead is toxic in that it hampers brain development. 电缆通常安装在地下，为的是延长其寿命。（目的状从） 既然我们已经仔细研究了自然科学的几个领域，现在不妨给科学下个定义。（原因状从） 铅有毒，因为铅会影响大脑发育。（原因状从） 第3节 翻译练习17 Unless the steam is superheated, higher pressure will be necessary. A copper wire is not affected unless there is electrical pressure. Usually substances can’t expand, unless they are heated. 如果蒸汽不是过热蒸汽，就需要较高的压力。 铜线不受磁铁的影响，除非它载有电流。 物质如果不受热，一般是不会膨胀的。 第3节 翻译练习18 Until the SCR was developed, the thyratron was the only controlled rectifier available. Rubber was known only as a natural product until its synthesis was achieved in 1916. Not until the jet engine had come into use could planes travel at supersonic speeds. 在研制出可控硅之前，闸流管是唯一可用的可控整流元件。 在1916年人工合成橡胶之前，人们只知道橡胶是一种天然产品。 直到喷气发动机投入使用，飞机才能做超音速飞行。 When the water temperature is increased, it vaporizes more quickly until it reaches boiling point. 水温升高时，水蒸发得越来越快，直到达到沸点为止。 第3节 翻译练习19 Precisely what happens to the atomic structure of metals at such low temperatures is still not wholly understood. Since sound travels differently through different materials, analyzing the sounds can reveal what the floor is made of. 在如此低的温度下金属的原子结构到底发生什么变化，还不完全清楚。（主从） 因为声音在不同的物质中传播情况不同，分析这些声音能够知道海底是由什么构成的。（宾从） A programmer must make out, in every detail, the problem to be solved in what is called machine language. These illustrations show what happens to the mixture after it enters the cylinder of the engine. The method of physics is to analyze first the simpler cases, to extract what we can from them, and to go forward to more and more complicated cases. What the image tube does is not hard to describe. 程序编制人员要用所谓的机器语言把要解决的题目详尽地编排出来。（宾从） 这些插图显示混合物进入汽缸后会发生什么情况。（宾从） 显象管的作用不难说清。（主从） 物理学的方法是首先分析一些较简单的事例，从中吸取我们所能吸取的知识，然后进一步分析越来越复杂的事例。（宾从） 第3节 翻译练习20 We don’t know when the best times are for seeing Mercury. We don’t know when they can give the transformers we ordered. This was the period when he began the research which resulted in the creation of his famous Theory of Relativity. 我们不知道观察水星的最好时机是什么时候。（主从） 我们不知道他们什么时候开始交付我们订购的变压器。（宾从） 就在这期间，他开始进行一项研究，通过这项研究创立了著名的相对论。（定从） In those years when electricity had not been discovered, people knew nothing of conductors and insulators. 在电还没有被发现的年代里，人们不知道有导体和绝缘体。（定从） 第3节 翻译练习21 When a substance is dissolved in water, the freezing point of the water is lowered. The SCR will only pass current when its gate is pulsed. Newton’s first two laws hold only when they are observed in unaccelerated reference frames. 当一种物质溶解于水时，水的冰点就会降低。 只有当可控硅的门电极受脉冲作用时才能让电流通过。 牛顿的第一、第二定律，只有在非加速的参照系中作观察时，才能成立。 An electric current exists when there are charges in motion. 如果有电荷运动，就存在着电流。 第3节 翻译练习22 Where the power station will be built is under discussion. Universal connectivity will bring together all the information and services you need and make them available to you regardless of where you are, what you are doing, or the kind of device you are using. 电站建在什么地方正在讨论中。（主从） 通用连接技术将能把你所需要的信息和服务收拢起来。而且无论你在哪里，无论你在做什么，无论你使用何种设备，它都能将这些信息和服务送到你手上。（宾从） Then arose the question where we were to buy the generators needed. Water power station must be built where there are water falls. Where the watt is too small a unit, we may use the kilowatt. 这时就产生了这样一个问题，我们到哪儿买所需要的发电机？（同位从） 水电站必须建在水有落差的地方。（状从） 在用瓦作单位太小的情况下，我们可用千瓦。（状从） 第3节 翻译练习23 Resistant and tolerant varieties can help mitigate tuber damage where nematodes are present. Most urban areas now have a TDD relay center, where operators serve as intermediaries between TDD users and standard-phone users. Surrounding every magnet there is a region where magnetic forces act. 在每一块磁铁的周围都有一个磁力作用的区域。（定从） 抗病虫品种可以有助于减缓线虫对球根的损害。（定从） 现在大部分城市市区都有“耳聋电信装置”中继中心，在那里接线员是“耳聋电信装置”用户和普通电话用户的中间人。（定从） The reducing top gas, containing 70 percent carbon monoxide plus hydrogen, flows from an outlet pipe located near the top of the DR furnace into the top-gas scrubber, where it is cooled and scrubbed to remove dust particles. 第3节 翻译练习24 The question is whether these relays and breakers come up to the mark. We wonder whether simpler and more inclusive conservation laws exist. There is no difference whether or not the temperature is kept constant. A waterfall, whether it is man-made or natural, also possesses energy. 我们不知道是否有形式更简单、运用范围更广泛的守恒定律。（宾从） 温度是否保持不变，这没有什么关系。（同位从） 问题是这些继电器和断路器是否合乎要求。（表从） 瀑布，不管它是人造的还是天然的，也具有能量。（状从） 第3节 翻译练习25 Which of these generators is the most efficient has to be tested. The problem is which generator you repair first. As to which of these apparatuses is the best, I can’t give you any definite answer. 这些发电机中哪一个最有效还有待试验。（主从） 至于这些装置中哪台最好，我不能作任何肯定的回答。（宾从） 问题是你先修哪一台发电机。（表从） 第3节 翻译练习26 Technology tries to find applications for new ideas which science discovers. In order to keep the engine speed within the limits which it was designed for, a device which is known as a governor is incorporated in the engine. The basic principle which a tape recorder functions on is that of magnetism. 技术力图为科学所发现的新思想找到应用。（定从） 为了使发动机的转速保持在所设计的范围之内，在发动机里装有被称为调速器的装置。（定从） 磁带录音机的基本工作原理就是磁性原理。（定从） Molecules in turn are made up of atoms, which are smaller particles still. An experimental station has been established off the Ivory Coast of Africa, which utilizes the different temperature levels of sea water. Light has a higher frequency than radio vaves or microwaves, which gives it a greater information carrying capacity. 分子本身又是由原子构成，后者是更小的粒子。（定从） 在非洲象牙海岸沿海已建立起一座试验性发电站，该发电站利用海水的温度级差来发电。（定从） 光的频率高于无线电波和微波，这就使它具有更大的信息运载能力。（定从） At present, microwave technology, which includes microwave heating and microwave survey, is being widely applied to industrial and agricultural production. Many people could find that videoconferencing yields productivity gains which make it worth the investment of time and money. 目前，微波技术，包括微波加热和微波测量，正广泛地应用于工农业生产。（定从） 许多人会发现，视频会议系统可以提高生产效率，因此它值得我们投入时间和金钱。（定从） 第3节 翻译练习27 Motion is absolute while stagnation is relative. New types of computers are smaller in size, while they are simpler in operation. Each face is an equilateral triangle, while three faces meet at each vertex. 新型计算机体积较小，而且操作也比较简单。 每一个面是一个正三角形，而且在每一个顶点有三个面相交。 运动是绝对的，而静止是相对的。 第3节 翻译练习28 While a crystal solid melts, there is no change in temperature. While there are heat losses in a steam turbine, I cannot prove it. While a spark of life remains, it is a doctor’s duty to save the patient. 当晶态固体熔化时，温度没有变化。 虽然涡轮机内有热损耗，但我无法加以证明。 只要病人还有一息生机，医生就有责任挽救。 第3节 翻译练习29 It is still not clear in my mind why a generator can produce power. This is why some conjugated polymers exhibit electro-luminescence. We all know why the ground loses heat to the air. 我仍然弄不明白为什么发电机能发电。（主从） 这就是为什么一些共轭聚合物具有电致发光的特点。（表从） 我们都知道为何地表把热量输送给空气。（宾从） The reason why elements emit radioactive rays is that they are constantly decaying. The reason why the turbine doesn’t work is the lack of lubricant. 元素射出放射线的原因是因为它们不停地在衰变。（定从） 那台汽轮机运转不灵的原因是缺少润滑油。（定从） 第7章 总复习题 The conductivity of polyacetylene drops rapidly in contact with air. There is a brighter future for intelligent devices in the home. The scientists found that the blood vessels in the leg cannot swell. Once upon a time, bold claims were made about computers, the future and the “paperless office”. 聚乙炔一接触空气，其导电性就迅速下降。 家庭智能装置仍有着更加光明的前景。（省译） 科学家们发现腿内的血管不会肿胀。 曾几何时，有人就有关计算机、未来和“无纸化办公”做过大胆的预测。 The doctor advised against the use of the new treatment. If a good base cannot be found at a reasonable depth, then a so-called deep foundation must be provided. Magnetic lines of force cannot be seen, but we know they exist by what they do. 磁力线是看不见的，但是我们按照它们的作用即知它们的存在。 医生建议不要使用新的治疗方法。 若在合理的深度内找不到坚实的地基层，那就要采用所谓的深基础。 We may process directly with Kirchoff’s voltage law for the circuit. The proper values of a and b are determined from two conditions. Optional communications are free from electromagnetic interference. This type of discrepancy could have resulted from differences in kinetics. a和b的值由两个条件决定。 对于电路，我们可直接从克希荷夫电压定律讲起。 光电通信不受电磁的干扰。 这种差异可能是由动力的不同而造成的。 The visual image of the letters making up the word is converted into its spoken equivalent. Primitive man made weapons, tools, and utensils of copper, brass, and bronze. The longer wavelengths of radio signals pass through the atmosphere relatively undisturbed. 将组成词的各字母的视觉形象转换成该词对应的发音。 相对来说，波长较长的射电讯号通过大气时没有受到干扰。 原始人类用铜、黄铜和青铜制作成各种武器、工具和器皿。 Most hardness-testing systems employ a standard load which is applied to a ball or pyramid in contact with the material to be tested. All metals are corrodible under the proper circumstances. The design of the rocket nozzle also has much to do with the behavior of the exhaust and the resulting velocity of the vehicle itself. 多数的硬度实验系统使用一标准载荷加在与实验金属相接触的小球或棱锥上。 所有金属在一定情况下都是可腐蚀的。 火箭喷管的设计与排气的性能及飞行器本身的有效速度有很大关系。 Peripheral milling operations are usually performed on milling machines with the spindle positioned horizontally; however, they can also be performed with end mills on vertical-spindle machines. Copper and aluminum are the best conductors of electric current only after silver. From various experiments we cannot but think the theory still holds good. 周铣作业通常在带有水平定位主轴的铣床上进行，但也可以在带有端面铣刀的主轴铣床上进行。 铜和铝是仅次于银的最好的导电体。 根据各种实验，我们不得不承认这个理论依然是行之有效的。 Hydrogen is generated from zinc and sulfuric acid. The sort of fish cannot live in the temperate zone, let alone in the frigid zone. The locomotive developed some new problems on its line-test. Gases can be chemisorbed or physically absorbed on solids. 氢由锌和硫酸所产生。 这种鱼不适合在温带生活，更不必说在寒带了。 这台机车在试运行时出现了一些新问题。 气体能化学吸附或物理吸附在固体上。 Under ideal conditions the fatigue failure will consist of a spotting of the load-carrying surfaces. Oxidation implies the combination of other elements with oxygen to form compounds. 在理想条件下，疲劳失效将是承载表面的点蚀。 氧化意味着其他元素与氧形成化合物。 第8章 第1节 翻译练习1 This gas (ozone gas) is found some 15 to 35 kilometers above the Earth’s surface in the upper atmosphere or “stratosphere”. 这一气体（臭氧）位于地球表面上空大约15-35公里的大气层或“同温层”。 Air load can be placed in equilibrium with inertia load. 气动载荷可以与惯性负载相平衡。 When opposing forces balance each other, a state of equilibrium or balance is reached. 当两个反方向作用的力相互抵消时，便达到平衡状态。 翻译练习 The microwave is featured by wide band and the ability to penetrate high altitude ionosphere without obstruction. 微波的特点是频带宽可无阻碍地穿过高空大气电离层。 The deck of the triple-hull submarine is situated much lower and in consequence better utilization of space is possible. 三层船壳潜水艇的甲板位置要低得多，因而有可能更好地利用空间。 Microscope continues to be a very important tool in science today. 显微镜仍然是今日科学中很重要的工具。 Such waves occur most frequently at stormy latitudes, where the storms tend to come in groups traveling in the same direction, with only short periods separating them. 首先，我们有可能注意到，有一系列附加因素在加速这一过程。 第1节 翻译练习3 As the flight speed increases, there comes a point where the flow reaches the local speed of sound. 随着飞行速度的增加，这一流动可能会达到局部音速。 The wheel is considered to be one of the greatest technical advances in human history. 轮子是人类历史上最伟大的技术进步之一。 There is confusion over the differences between basic and applied research. 基础研究和应用研究之间的区别分辨不清。 In contrast to conductors, there are very few free electrons in an insulator. 与导体完全不同，绝缘体中自由电子很少。 Consideration should be given to the amount of wear likely to take place before the next inspection falls due. 必须考虑到下次检修之前可能发生的磨损量。 Like the gasoline engine, the diesel engine generally is constructed with several cylinders. 像汽油机一样，柴油机通常也有数个气缸。 第1节 翻译练习4 Glass does not conduct electricity, neither does the air. 玻璃不导电，空气也不导电。 The electric power can be transmitted either by means of d.c. or a.c. 电既可以直流传输，也可以交流传输。 At the next station the angry conductor put Edison and all his things off the train. 到了下一站，气冲冲的列车员把爱迪生赶下了火车，并把他所有的东西都扔了下去。 第2节 翻译练习1 The technique is used to detect flaws in equipment. 该项技术被用来探测设备的缺陷。 Conducting an electric current means transmitting electrons. 传导电流就意味着传送电子。 Control of the refrigeration process is simplified by the use of a liquid subcooling control valve. 冷冻过程的控制可采用一个液体过冷控制阀而得到简化。 第2节 翻译练习2 That winter, I did not know the principles of work of this machine, not to speak of designing it. 那年冬天，我连这台机器的操作原理都不懂，更不用说设计这种机器了。 They worked out new control elements, making the operation much easier. 他们研制出了新的控制元件，从而使操作容易多了。 He said he would check up and repair these transformers. 他曾说过他要检查和修理这些变压器。 第2节 翻译练习3 There will be more and more telephones in the futures, and they will be better ones. 将来会有越来越多的电话机，而且它们将更好。 Decisions about site, silviculture and genetics will affect harvest volume and log and wood properties. 有关场址、造林术和遗传学的决策将会影响产量以及圆木和木材性质。 Fossil fuels will continue to act as the principal fuel source in the first quarter of the 21st century. 矿物燃料的21世纪在头25年里将仍然是主要的燃料来源。 第2节 翻译练习4 In recent years scientists have found chemicals that affect mood, memory, and other happenings of the mind. 近年来，科学家们已经发现了一些会影响情绪、记忆、以及其他精神活动的化学物质。 Some makers have already moved to 17-inch models as their focus while others are keeping the attention on the 15-inch line. 有些制造商已经将注意力转移到17英寸显示器的生产，而其他一些制造商则仍主要生产15英寸显示器。 Environment Canada has also invented a very sensitive instrument that takes ozone layer measurements from the ground. 加拿大环境部门已经发明了一种十分敏感的检测仪，它能从地面测量臭氧层数据。 第2节 翻译练习5 Now attempts are being made to increase the proportion of electrically powered vehicles on the road, particularly by manufacturing an ordinary motor car thus powered. 目前正试图增大道路上电动车辆的比例，特别是要生产电动的普通汽车。 Today the role of neuropeptides in human behavior is creating much interest. 目前，神经肽对于人类行为的作用正在引起人们的很大兴趣。 People are still talking about the historic events of last week, when the first spacemen circled the earth. 人们还在谈论上星期的历史性事件，第一批太空人环绕地球飞行。 第3节 翻译练习1 Water necessary for the seed to germinate. 种子发芽需要水分。 It is vital to ensure that a patient is not one of the minority before cutting into his right hemisphere. 在对大脑右半脑进行手术之前，确信病人不是那些少数人之一是非常重要的。 It is usually best to avoid substitution of numerical values until the final formula has been obtained. 在得到最后公式之前，最好不要代入数值。 It is rather difficult to define this quantity precisely. 对这个量要精确地下定义是相当困难的。 When reading a thermometer, it is essential to hold the instrument in an upright position, otherwise the reading may be wrong. 读取温度计示数时，一定要使温度计保持直立的位置。 It is often necessary to multiply a quantity by itself a number of times. 常常需要将一个量自乘若干次。 It is difficult to remove the impurities from the solution. 很难将溶液中的杂质去除。 The phenomenon is difficult to explain. 这个现象很难解释。 第3节 翻译练习2 The idea here is to locate, in the weather records, conditions that are as analogous to the current conditions as possible. 灯泡底座的两个接触头通过灯座借以传送电流。 One way in which costs can be minimized in manufacture or construction is to use standard parts. 将生产或制造成本降低到最低限度的一种方法就是采用标准部件。 The only way a home computer can effectively deal with the huge amounts of data required for good quality video is to compress it. 家用电脑有效处理高品质视频所需大量数据的唯一途径就是压缩。 第3节 翻译练习3 The use of parallel circuits makes it possible to switch any light or appliance on or off without affecting other circuits. 使用并联电路使我们可能开关任何电灯或电器而不影响到别的电路。 There bees and hummingbirds help pollinate plants and a colony of termites aid in the decomposition of dying material. 在那里，蜜蜂和蜂鸟有助于给植物传授花粉，成群的白蚁能促进枯萎的枝叶分解。 They forgot to include some other alloying metals into the alloy. 他们忘了在合金中放入某些其他的合金金属。 第3节 翻译练习4 The study of thermodynamics enables us to predict which processes or reactions might occur spontaneously. 对热力学的研究使我们能够预计哪些过程或反应可以自发的进行。 Short circuits would cause very strong currents to flow. 短路会使得很大的电流通过。 The new information led scientists to assume that Venus rotates on its axis very slowly. 这一新信息使科学家们设想，金星及其缓慢地饶轴自转。 第3节 翻译练习5 The carrier wave is modulated to transmit the signal. 通常用微粒除尘机控制粉尘污染。 The spark is timed to occur before the piston reaches top dead center, otherwise maximum pressure would not be reached in time. 火化应定在活塞到达上死点之前出现，否则不能按时达到最大的压力。 Turbine blades must be produced to withstand creep and corrosion. 绝缘体用来把电流限制在所要求的路线中。 第3节 翻译练习6 Even though the ozone layer is an invisible shield, scientists have found a number of ways to measure it. 臭氧层是一种不可见的保护层，不过科学家们已经找到了多种测量它的方法。 People are searching for the new and better ways to prevent factories from sending out poisonous gases and polluted water. 人们正在寻找防止工厂排放有毒气体和污水的新的更好的方法。 There was simply no visible evidence to support such a theory. 根本看不到有任何明显的证据来支持这一理论。 第3节 翻译练习7 To get a great amount of water power we need large pressure and current. 要得到巨大的水力，就需要高水压和大流量。 All air would be passed through a cleaning system to remove dust particles, pollen, noxious gases, and other pollutants. 所有的空气都通过净化系统来消除灰尘、花粉、有害气体及其他污染物。 The problems include the development of processes (catalytic converters, effluent treatment facilities) to minimize the release of or deactivate products harmful to the environment. 问题包括开发加工技术（催化转换器、污水处理设施）以尽可能地减少排放对环境有害的物质，或使有害物非活性化。 This causes the belt to wedge itself into the groove to increase the friction. 这就使得本身契入槽中，以增大摩擦。 A resistor is placed parallel with another only to make the current greater. 一只电阻箱与另一只电阻器并联，从而使电流变大。 Sophisticated technology devices for disabled people are often expensive to buy and to produce. 供残疾人使用的先进技术设备的生产成本和购买价格往往很高。 第3节 翻译练习8 Thanks to fast printers and copiers, producing a high-quality document on paper has become much easier. 由于高速打印机和复印件的出现，制作高质量纸张文档变得极为容易。 Eliminating popular misconceptions about disability can also play a role in enabling the visually and hearing impaired to live on equal terms with the sighted and the hearing. 消除普遍存在的对残疾人的错误看法也有助于使视力和听力损伤者与耳聪目明的健康人平等的生活。 Increasing its diameter will decrease the resistance of a wire. 加大导线的直径会降低其电阻。 第3节 翻译练习9 Arc welding is making metals together by means of an electric current. 电弧焊是利用电流把金属溶解在一起。 One basis of a biometric verifier is analyzing the dynamics of the way a person signs his or her name. 生物统计学核实器的一个基本点的分析一个人签名时的书法笔力。 The aim of document management software is reducing the workload and improves the productivity of most offices. 文档管理软件的目标就是要减少大多数办公室的工作量并提高工作效率。 第3节 翻译练习10 We avoided using an expensive component by redesigning the circuit. 我们重新设计了电路，避免了使用一种昂贵的元件。 The majority of alloys are prepared by mixing metals in the molten state. 大多数合金是将熔态的金属混合制成。 A clean machine gives all concerned the feeling or producing a high-quality printing product. 一台洁净的机器给各有关人员的感觉是能生产出高质量印刷产品。 第3节 翻译练习11 Mounting the panel model on a short strut has the advantages of decreasing the tare drag of the setup. 把翼片模型安装在一个短支柱上，其优点是减少了安装支架的阻力。 There are four ways for transmitting power from the electric motor to the spindle. 有四种方法可以把动力从电动机传到主轴。 An important consideration in making resistance calculations is the effect of temperature on resistivity. 在进行电阻的计算时，应重点考虑的一点就是温度对电阻率的影响。 第3节 翻译练习12 The major advantages of the transistor as used in electronic circuits are light weight, small space, low power consumption. 使用在电子电路中的晶体管的主要优点是重量轻、体积小、耗电量低。 Association is the basis of conditioned reflexes. 心理联想是条件反射的基础。 Submarines can assume any desired depth between the surface and the sea floor by changing their densities. 潜水艇通过改变自身的密度可以达到介于海面与海底之间所期望的任何深度。 The need for after-treatment can be avoided by using better prepared feedstock. 利用一种较好的、经过特别处理的原料，就可以不必进行后处理。 Specialists in all branches of mechanical engineering are keenly aware of the necessity of replacing machines with periodic operation by continuously operating machines. 机械工程各部门的专家们都深深感到必须用连续操作的机器来代替间歇操作的机器。 The amount of heat given out by the heater increases in direct proportion to the length of time the heater is on. 加热机器所放出的热量与加热器开的时间长短成正比。 Robots will be carrying out many tasks at present carried out by men. 机器人将完成目前由人来做的许多工作。 The test specimen prepared from the test samples selected from copper rods shall meet the requirements of this standard. 用从铜棒中选取的试样制成的试件必须符合本标准的技术要求。 The only semiconductor element used in early 1940s-style microwave circuits was the crystal detector diode. 在20世纪40年代早期微波电路使用的唯一的半导体器件是晶体检波二极管。 The product should pass all the environment tests as specified in the table 6. 产品应用通过表6所规定的全部环境试验项目。 In fact, materials as used in transistors do not exist in nature but are man-made. 实际上，晶体管中所用的材料是人造的，在自然界中并不存在。 Curved surfaces may reflect light regularly. 曲面会规则地反光。 Whenever current flows in a circuit containing resistance, a voltage appears across the terminals of the resistance. 每当电流流过具有电阻的电路时，电阻两端之间会出现电压。 Automation makes skilled labor available for more creative occupation. 自动化技术使熟练的劳动者能从事更有创造性的职业。 The typical problem of circuit and network theory is to determine the currents caused by the application of a given voltage to a given circuit or network. 电路和网络理论的典型问题是确定将一定电压加于一定电路或网络所引起的电流。 第3节 翻译练习13 Pig iron contains a number of impurities, including carbon from the coke. 生铁含有一些杂质，其中包括来自焦炭的碳。 Every crane has a certain lifting capacity, ranging from a few tons to many hundreds of tons. 每台起重机均有一定的起重力，该起重力从几吨到几百吨不等。 The electric charges which flow in mental to form what is called electric current are electrons belonging to metal atoms. 在金属中流动从而形成所谓电流的电荷属于金属原子的电子。 第3节 翻译练习14 I found the spring removed from the machine unharmed. 我发现此弹簧从机器上拆下以后没有损伤。 A watt of power will keep a current of one ampere flowing in a circuit under a pressure of one volt. 一瓦电能使一安培电流在电压为一伏的回路中流动。 第3节 翻译练习15 Observed in unaccelebrated reference frames, Newton’s first two laws hold. 在非加速的参照系中作观察时，牛顿第一、第二定律才能成立。 Having been well insulated, the wire may be used as a conductor. 经过良好的绝缘之后，金属线可用作导体。 Having reached boiling point, water vaporizes more quickly. 水在达到沸点之后，蒸发得越来越快。 When making identifications, biometric systems read in a user’s characteristics. 进行身份鉴定时，生物统计学系统读入使用者的特征。 第3节 翻译练习16 Looking at a cross section of a water wave, we may see that it is periodic in character. 如果观察水波的横截面，我们就会发现水波具有周期性。 Living in a space shuttle, human beings will meet with some problems such as weightlessness and lacking of oxygen. 假如人类生活在航天飞机上，就会碰到失重和缺氧等问题。 Using a transformer, we can increase or decrease the voltage of an alternating current. 如果使用变压器，就可以升高或降低交流电的电压。 第3节 翻译练习17 Such a reaction can be very dangerous, causing the cutoff of your oxygen supply. 这种反应可能造成很大危险，因为它能切断你的氧气供应。 Designed to be earthquake-proof, the tunnel can move laterally up and down or slide endwise. 由于是按防震要求所设计的，这条隧道可以左右、上下移动或向两端延伸。 第3节 翻译练习18 Possessing many excellent features, the three-phase induction motor is not a variable-speed machine. 三相感应电动机虽有许多优点，但不是变速电机。 Highly mechanized, the food and textile industries still rely on the human senses for certain essential operations. 食品业和纺织业虽已高度机械化，扔依赖于人的感官来进行某些重要的工序。 Considered a difficult material to weld, aluminum is, in fact, one of the most readily weldable of all metals. 肃然铝被认为是一种难焊的材料，事实上确实所有金属中最容易焊接的金属之一。 第3节 翻译练习19 Bricks are produced in standard sizes, making them easy to handle. 通常的砖都具有一定的尺寸和规格，这样容易砌筑。 Its hot innermost constituents drifted farther inward, enlarging the protosun. 星云盘最里面的高温部分进一步向内漂动，使原始太阳增大。 The expanding gas rotates the turbine, thus giving up a large part of its power. 膨胀的气体转动涡轮机，从而放出了大部分的动力。 第3节 翻译练习20 Using a magnetic or electric field, the emanations from radioactive elements can be separated into three components——alpha particles, beta particles, and gamma rays. 发动机可以是气冷式的或是水冷式的，后者更为常见。 Depending on their method of functioning, a distinction is be to made between hydraulic and mechanical presses. 根据其工作方法，可以把压力机区分为水压机和机械压力机。 Bats fly through the darkest nights not hitting anything except their intended targets——months and other flying insects, which the bats hunt and eat. 蝙蝠在漆黑的夜晚飞翔，除了想要捕捉和吞噬目标——蛾子和其他飞虫——之外，不会碰到任何东西。 第3节 翻译练习21 The voltage being kept constant, the current varies inversely with the resistance. 电压保持不变时，电流和电阻成反比。 Simple substances consist of atoms, each substance having its special atoms. 简单物质都由原子组成，每种物质都有它特有的原子。 第4节 翻译练习1 All-mental locknuts can withstand temperatures above 300C。 全金属自锁螺母能耐300度以上的高温。 The network can take care of its own devices. 这种网络能监控自身的设备。 We can readily visualize an object carrying a charge. 我们能够很容易地观察到一个物体带电。 Heat cannot flow spontaneously from a cooler to a hotter body. 热决不会自发地从低温物体流向高温物体。 As shown in Fig.8, the resultant current could not fall to zero. 如图8所示，合成电流决不会降至零。 With expensive editing computers, you could edit video just like a document with cutting and passing. 使用昂贵的编辑用计算机，你可以像编辑文档一样编辑视频材料，对其进行剪切和粘贴。 A beam of electrons can be bent by passing it between a magnet’s poles. 使一束电子通过磁铁的两极之间，可使电子束方向偏斜。 This can hardly happen unless the fuel tank is broken. 这种情况几乎不可能发生，除非油箱破裂。 第4节 翻译练习2 In cold weather, water may freeze in the engine cooling system. 在寒冷的天气里，发动机冷却系统中的水可能会凝固。 An excessive pressure of steam might cause the boiler to explode. 过高的蒸汽压力可能会引起锅炉爆炸。 There are peptides that may change or improve, for example, creativity, intelligence, imagination, and memory. 有些肽可能改变或提高诸如创造力、智力、想象力和记忆力。 But if the star is very large (much bigger than our sun), this process of shrinking may be so intense that a black hole results. 但是如果这种恒星很大（比太阳大得多），它的收缩过程可能非常剧烈，结果产生黑洞。 I made a hole here in order that the temperature inside the case might be measured. 我在这里打了一个洞，以便测到盒子里面的温度。 We may illustrate molecular motion in liquids by the following experiment. 我们可以通过以下试验来说明液体中的分子运动。 Please test the insulation of the wire so that we may be sure it is safe to use. 请试验一下这根导线的绝缘性能，以使我们确信导线可安全使用。 If a way could be found to harness the reactions, they might be used to make valuable chemical products. 假如能找到一种利用这些反应的方法，这些反应或许能用来生产贵重的化学制品。 Were there no electric pressure in a semiconductor, the electron flow might not take place in it. 如果半导体没有电压，半导体内就不会产生电子流动。 第4节 翻译练习3 The drug must be taken at exactly the right time and in the right doses, and are only the rudimentary precursors of an eventual jet-lag or shift-work pill. 必须完全准时并严格按计量服用这些药，而且这些药只不过是未来的飞行时差或轮班工作药的初级形式。 The current rating of the cable must not be exceeded. 不得超过电缆的额定电流。 The oil pressure must not be under the scale, otherwise it will bring great damage to the engine. 油压不得低于刻度要求，否则会引起发动机严重损坏。 This must be interpreted as a sign of hypothyroidism. 这只可能解释为甲状腺机能减退的一种现象。 There must be something wrong with that generator; it does not work. 电机肯定出了毛病，它不工作了。 The units must have been installed by now. 机组现在一定安装好了。 第4节 翻译练习4 Need we make any adjustment to this meter before application? 使用之前我们有必要调试这台仪器吗？ This circuit cable need not be rated at any more than 23A. 这条电路电缆的额定值不必超过23A。 Once the reaction has started, no more external heat need be applied. 反应一开始就不需要外部加热了。 第4节 翻译练习5 Economic contracts shall be in written form. 经济合同必须采用书面形式。 A notice not smaller than 65mm by 50mm shall be fixed to the container marked “Danger, High Voltage.’ 在外壳上必须钉上一块面积不小于65mmX50mm的标牌，上写“高压、危险”字样。 The temperature range through which the equipment shall operate is 180°to 90°. 设备的工作温度一定要在180度到90度之间。 第4节 翻译练习6 Sometimes we should have the stresses at directions other than those given by the equations. 有时要与公式所定的方向不同的应力。 We should choose the right motor for each kind of work, since motors of different types differ in their characteristics. 既然不同类型的电动机的性能有别，我们应该按不同工种来选用适当的电动机。 Ships should not discharge oil into the open sea. 船舶不得把污油排入公海。 A spare set of brushes should be of proper rating. 一套备用电刷应有适当的定额。 Provided that the cost is reasonable, this design should be accepted. 倘若成本合理，这项设计有可能被采纳。 Should there be urgent situation, press this red button to switch off the electricity. 万一有紧急情况，请按红色按钮以切断电源。 Should the current be cut off, the coil will return to its original. 一旦切断电流，线圈即恢复到原来状态。 We use insulators for fear that electricity should leak away from the wire. 我们使用绝缘体，以免漏电。 We must check and recheck the results of our experiments lest there should be any errors in them. 我们必须反复核对实验结果，以免发生差错。 Electrochemical machining should have been better than mechanical methods of mental removal. 用电化加工方法本应该比用机械方法切削金属的效果好。 You should not have kept those cells in the damp place. 你本不该把那些电池放在那块潮湿的地方。 第4节 翻译练习7 The computer will be preprogrammed to draw macros. 计算机可按预编程序绘出宏指令表示的内容。 It may well be that speed alone will not be the main emphasis in the future aviation design. 在未来的飞机设计中，很可能不再单单强调速度。 Most people would describe water as a colorless liquid. 多数人会把水描述成无色的液体。 Part replacement will decrease if machine adjustments are checked on a regular basis. 假如机器调试精度得以定期检查的话，那么零件的更换也会减少。 Together, we will take action by phasing CFCs and other ozone-depleting chemicals out of our lives. 总的来说，我们可以采取行动，在我们的生活中逐步停止使用氟利昂和其他消耗臭氧的化学品。 Without its atmosphere the earth would have a very high daytime temperature. 假如没有大气层，地球白天的温度将会很高。 Sound will not travel through vacuum. 声音不能通过真空。 If the engine could be made to work in this way, it would have an efficiency of 100%. 假若能使发动机这样来工作，它会有100%的效率。 第5节 翻译练习1 For transmitting rotary motion and torque around corners, bevel gears are commonly used. 为了使转动和转矩能绕道传递，常常使用伞齿轮。 The types of roofs are, generally speaking, divided into two, these being flat and pitched. 通常，屋盖可分为平屋顶与坡屋顶两种。 The element values of the filter may be chosen as desired. 滤波器的额定值是可以任意选取的。 Some types of pneumonia can’t be treated with antibiotics. 有些类型的肺炎是不能用抗生素治疗的。 The pump is designed specially for use with the Doxford engine. 这种泵的设计专门用于与多克斯发动机配合使用。 第5节 翻译练习2 The problem was solved by adding a capacitor. 安装一个电容器就解决了这一问题。 This type of system was required by building with large glazed areas. 装配玻璃面积很大的建筑需要安装这种系统。 A vehicle was devised a few years ago which permitted movement over difficult land and could fly for a short distance. 几年前人们设计了一台能在难以行走的土地上移动并能短距离飞行的交通工具。 Attempts have been made to use fuel cells for central power stations but with little success. 人们所进行过的将燃料电池用于中心电站的尝试都未获成功。 Radioactivity is found on both sides of the failure plane in all cases. 在任何情况下，破断面的每一翼面都发现有放射性。 Three-phase current should be used for large industrial equipment 大型工业设备应使用三相电流。. Tigers are found in India and most of the countries of Southeast Asia. 印度以及东南亚地区的大多数国家都有老虎。 If one is discovered to have developed high blood-pressure or heart-disease, he is immediately transferred to light work. 如果发现谁得了高血压或心脏病，就立即调他去做轻松的工作。 第5节 翻译练习3 For any machine whose input and output forces are known, its mechanical advantage can be calculated. 对于任何机器来说，如果知其输入力和输出力，就能求出其机械效益。 Reinforced concrete roofs are often constructed nowadays, especially where there is a risk of fire. 从防火要求考虑，目前多采用钢筋混凝土屋顶。 An almost identical cracking problem was encountered in the production of cast 713 turbine blades. 在生产712铸造汽轮机叶片时，碰到了一个几乎相同的裂纹问题。 第5节 翻译练习4 When current is made to flow through a coil, the sort iron core is magnetized. 当电流通过线圈时，软铁心便被磁化。 The term is used to describe an interlinked system of documents. 该术语被用来描述文件连接系统。 Atoms in molecules are bound by covalent bonds. 分子式的原子被共价键所束缚。 The speed of a generator is controlled by the prime mover. 发电机的转速受原动机控制。 Without the ozone layer, plants and animals would also be affected. 如果没有臭氧层，动植物也将受到影响。 第5节 翻译练习5 All elements are made up of atoms which in turn are made up of electrons, protons, and other minute particles. 所有单质都有原子组成，而原子又由电子、质子及其他微小的粒子组成。 All the alternative routes are given to car drivers by computers. 所有供选择的路线都由计算机显示给汽车司机。 The transistor was created by two Bell scientists, Brattain and Bardeen. 晶体管是由贝尔实验室的两位科学家布拉顿和巴丁发明的。 Entire epochs have been named for materials. 人类往往用某种材料来命名一个时代。 His equipment is made from flat pieces of copper and aluminum arranged so that electricity can go through them. 他的设备是用几片扁平的铜片及铝片组成的，其组合方式可让电流通过。 第5节 翻译练习6 This process is characterized by the smelting reduction furnace with two-stage tuyeres of a coke packed bed type. 这种工艺是以使用带两极风口的焦炭填充床的熔融还原炉为特点的。 Oil is discharged from the tank by a pump. 油是靠泵压从罐中放出的。 Microwave circuits (e.g. , couplers, amplifiers, oscillators, detectors, etc.) were intensively developed during the World War two to meet the pressing military demands of radar, in particular. 在第二次世界大战期间，为了满足急迫的军事需求，尤其是对雷达的需求，微波电路（如耦合器、放大器、振荡器、检波器等等）得到了极大的发展。 Problems should be resolved in good time. 有问题要及时加以解决。 These circulation anomalies have long been recognized. 这些环流异常现象早就为人们所认识。 This method was adopted for the following reasons. 之所以采用这种方法，有以下几个原因。 Steel is widely used in engineering, for its properties are most suitable for construction purposes. 钢之所以广泛地用于工程中，因为钢的性能非常适合于建筑使用。 第5节 翻译练习7 Veterinary services should not be considered a luxury. 不应把兽医服务看成是一项奢侈服务。 In the case of an orbiting space vehicle, centripetal fore is applied to the vehicle by the earth’s gravity. 当宇宙飞行器沿轨道运行时，地球的引力把向心力作用于飞行器上。 When such motors are used, they are usually built into the equipment by the machinery manufacturer, as in portable tools, office machinery, and other equipment. 这类电动机的使用通常是由机械制造商把它们直接安装在设备中，如便携式工具、办公机械及其他设备。 第5节 翻译练习8 Naïve rats and frogs are said to have reacted wildly to such proposed environmental change. 据说首次用来做实验的鼠和蛙对这种拟定的环境改变都有剧烈的反应。 It is generally accepted that irradiation is destructive to human tissues. 一般认为，辐射对人体组织是有害的。 It has been observed that for a long time it was incorrectly believed that current flowed from positive to negative. 我们已经注意到，人们过去长期错误地认为电流是由正极流向负极的。 It is now known that food protein is not absorbed as such, but must first be broken down into constituent amino-acids. 人们已经发现，食物中的蛋白质不能按其原来的形式加以吸收，必须首先分解为氨基酸。 总复习题 The stator of the induction motor is made up of a laminated silicon-steel core and a stator winding. 感应电动机的定子由硅钢片制成的铁芯及定子绕组构成。 Since air has weight, it must press down on the surface of the earth. 由于空气具有重量，它必定对地球表面有压力。 Computer language is based on the binary system. 计算机语言以二进制为基础。 This electrical pressure acts much like water in a tank. 这种电压的作用很像是水箱中的水压。 The Spirotherm equipment gives the operator a good picture of the temperature distribution over the top of the burden. 利用Spirotherm装置，操作者可获得一个较好的炉顶物料温度分布图。 Again, the stainless steels do not have this second characteristic, but most metals do. 另外，不锈钢不具备这第二种特性，但大多数金属都具备。 Several research groups are concentrating on finding new methods of delivering drugs to the body. 几个研究小组都在集中精力探索向人体释放药物的新方法。 It is frequently advantageous to stake the surveying lines perpendicular to the known or presumed geological strike. （在做物探测量时）将侧线垂直于已知的或者假定的地质走向标出，通常是比较有利的。 It is impossible to secure real economic and political independence of a country without developing its heavy industry. 不发展重工业不可能确保一个国家经济和政治的真正独立。 It is necessary to have a very large heating surface within the boiler. 锅炉里面必须有很大的受热面。 According to Albert Einstein, it is possible to change mass and energy into each other without a loss. 根据爱因斯坦的观点，质量和能量可互相转换而没有任何损耗。 In this way it is possible to make strong magnets. 用这种方法可以制造出很强的磁铁。 Such a bearing is designed to provide lubrication to reduce friction. 这样的轴承用来提供润滑以减少摩擦。 The hopper machine gives a substantial increase in loading rate as against the standard loader. 与一般的装载机相比，这种漏斗车可以大大提高装载速度。 The reduced pressure causes the inlet valve to open. 压力降低使得进给阀门打开。 Gases exhaled by volcanoes became the atmosphere of Venus, Earth, and Mars. 火山喷出的气体形成了金星、地球和火星的大气层。 The operation allows surplus energy to be used. 这道工序可以使剩余的能量得到利用。 We burn fuels in engines to make them work. 燃料在发动机里燃烧以使机器工作。 One of the objects of a well designed circuit is to avoid interference between components. 设计良好的电路所要达到的目的之一便是避免元件之间的干扰。 In one kind of transistor, there are three wires fastened to the crystal of germanium. 有一种晶体管，在锗晶体上面牢系着三根导线。 In the United States the customary voltage for household use has become 110-120V since it was discovered that higher voltages could cause fatal accidents. 美国通常的家用电压是110-120伏，因为人们发现，更高的电压会造成致命的事故。 Plant height was highly correlated with maturity, indicating that population with short stems tends to be early in maturity. 植株的高度与成熟期有密切的关系，这说明矮秆群体往往会早熟。 All other conditions being equal, we should first adjust the instrument to “zero”. 其他条件相同的情况想，我们应先把仪器调整到“零位”。 In the 1930’s, it was found that the atom could be split, releasing huge quantities of energy. 20世纪30年代人们就发现原子可以分裂并释放出大量的能量。 On the other hand, owing to the smaller furnace the gas utilization and thermal efficiency might become low. 另一方面，由于炉子小了，气体的利用率和热效率可能要降低。 An equipment failure or accident on the moon could have left the astronauts stranded. 在月球上如果有一种设备失灵或出事会使宇航员们束手无策、进退两难。 In order to keep the instrument in a good state ready for use at any time, it should go through necessary calibration regularly. 为确保仪器经常处于良好的可使用状态，平时必须定期对仪器进行必要的检测。 If the rope should break, the pulley would fall down. 一旦绳子断了，滑轮就会掉下来。 Sometimes it is desired that both the driver and the driven wheel rotate in the same direction. 有时希望主动轮和从动轮都向同一方向转动。 It will be appreciated that the necessity of providing a commutator with its carbon brushes complicates the construction of the motor. 我们可以理解，必须给换向器装备碳刷会使电动机的结构复杂化。 An interesting machine has been made to replace workers for dangerous jobs. 已造出一种有趣的机器代替工人做危险的工作。 Ceramics have long been limited by their brittleness. 易碎这个弱点长期以来限制了陶瓷的发展。 Investigators suspect that the virus was brought into the country through waste food. 调查人员怀疑，食品垃圾把这种病毒带入了该国。 第9章 第1节 翻译练习1 Hydraulic springs are particularly suited for applications in which high load capacities and stiffness are required. 液压弹簧尤其适用于要求承载能力和刚度很高的地方。 We can regard the entire weight of a body as concentrated at its center of gravity. 我们可以认为物体的整个重量像是集中在物体的重心上。 Installing the electronic units in the ground and leasing telephone wires would cost $15 million. 安装地下电子装置和租借电话线就要耗资一千五百万美元。 Introduction of a newly-developed technique will enhance the prospects of success. 引进一项新开发的技术将增加成功的希望。 第1节 翻译练习2 Since the lines of magnetic force converge and diverge, there is the necessity for a component Br. 由于磁力线的汇聚和发散，就必须需要一个分量Br。 Attempts have even been made to rename the robot. 人们也一直在尝试给机器人重新命名。 第1节 翻译练习3 Several concepts are introduced: decision-making, modeling, dynamics, feedback, stability, and logical design. 这里介绍几个概念：判定、模拟、动力学、反馈、稳定性和逻辑设计等。 Provision is made within the circuitry to limit the transistor voltage. 电路已采取措施来限制晶体管的电压。 See to it that all troubles should be eliminated. 务必要排除所有故障。 No direct electrical connection to the rotor is provided. 转子没有直接的连接电线。 The hinge-pin reactions are found by taking a summation of the horizontal and vertical forces. 分别求出水平方向和垂直方向各力之和，即可得铰销反力。 Up to now, there have been three main options for encoding a message. 迄今为止，消息的编码有三种主要的选择。 Provision must be made for dissipating the heat that results from the sliding of surface. 必须采取措施驱散因表面摩擦所产生的热。 It can be concluded that copper oxide is a more stable compound than mercuric oxide. 我们可以断言，氧化铜是比氧化汞更为稳定的一种化合物。 From this experiment the conclusion is drawn that the theory of oppositely charged particles attracting each other is true. 由这一实验可以得出结论，带异性电荷的粒子相互吸引的这一说法是正确的。 第1节 翻译练习4 The experiments are designed to validate his theory. 这些试验的设计是用来证实他的理论的。 Good clocks have pendulums which are automatically compensated for temperature changes. 好钟的钟摆可以自动补偿温度的变化。 An atom of oxygen is 16 times as much as an atom of hydrogen in weight. 一个氧原子的质量相当于一个氢原子质量的16倍。 A semi-conductor material is poorer than a conductor in conductivity. 半导体材料的导电性比导体的差。 第1节 翻译练习5 The collapse of the dam caused the land being flooded. 由于水坝倒塌，土地因此被淹没。 Restricted movement led to an interruption of blood flow. 由于活动受限制导致血液流动受阻。 第1节 翻译练习6 Any friction between two surfaces results in a temperature rise of the materials. 两个表面之间的任何摩擦都会导致材料的温度升高。 The rivets contract as they cool, drawing the plates together. 铆钉随着冷却而收缩，从而使钢板紧紧地压在一起。 And the direction in which the sound is traveling tells the bat where the meal is located. 同时，声音传播的方向能告诉蝙蝠事物的位置。 第1节 翻译练习7 The experiment resulted in the discovery of a cure for cancer. 这一实验的结果是发现了一种治疗癌症的方法。 The application of surfactants aims to simplify work processes. 使用表面活性剂的目的就是简化工作工程。 第1节 翻译练习8 Weight varies slightly in different places of the earth, depending on the force of gravity. 物体的重量在地球上的不同地点都会稍有变化，它取决于引力的大小。 The dial is scaled into one hundred graduations. 该标度盘刻有分成100等分的标度。 第1节 翻译练习9 The pressure was determined to be 0.1 torr. 所测得的压力为0.1托。 The power station managed to maintain its supply of electricity day and night. 电站尽力地保持日夜供电。 第1节 翻译练习10 Measurement of the lateral strain can be accomplished using a lateral extensometer. 侧向应变可用侧向伸长计来测量。 Any body which is capable of doing work is considered to possess energy. 任何能做功的物体都具有能量。 第1节 翻译练习11 The moment when light leaves a distant star and the moment when it reaches our eyes are not simultaneous; they may be separated by millions of years. 光离开遥远的恒星的时刻和它到达我们眼睛的时刻不是同时的，期间可能相隔几百万年。 The basic goal of high-definition television is to increase the number of lines in a television picture, thus sharpening it. 高清晰度电视的基本目标是增加电视图像的扫描线数量，从而使图像清晰。 An added benefit is that less noise is generated. 一个附带的好处就是所产生的噪音小。 第1节 翻译练习12 Carbon dioxide is denser than air. 二氧化碳的密度比空气大。 Rubber is a better dielectric but a poorer insulator than air. 橡胶的介电性比空气好，但绝缘性比空气差。 第1节 翻译练习13 If you’re watching a game in the ballpark, the network will know that player profiles are what you need on your palm-sized computer. 如果你在球场观看一场比赛，网络会知道你希望掌上电脑提供的是每位球员的简介。 One of the well-known laws of physics is Ohm’s Law. 欧姆定律是物理学上著名的定律之一。 It is a matter of common experience that it is much easier to roll bodies along than to slide them. 通常的经验是物质向前滚动比向前滑动容易得多。 第1节 翻译练习14 These new machines are now in wide use. 这些新机器正在被广泛使用。 The sum of the power dissipation is equal to the power delivered by the current source. 总共消耗的功率等于电流源发出的功率。 第1节 翻译练习15 As most metals are malleable and ductile, they can be beaten into plates and drawn into wire. 由于大多数金属都具有延展性和韧性，所以可以压成薄板和拉成细丝。 The angular-contact bearing is of greater thrust capacity. 向心推力轴承具有较大的轴向承载能力。 第1节 翻译练习16 The iron in the ship caused a deviation of the magnetic needle of the compass. 船体里的铁引起指南针磁针的偏离。 All moving bodies have energy. 所有运动的物体都具有能量。 第1节 翻译练习17 A radio antenna should have a physical size of one-half wavelength or more. 无线电天线的实际尺寸应为办个波长或更大一些。 Animals and plants have characters with variation. 动植物的特性是可变的。 There are radioactive isotopes of every element, either those existing in nature or else those activated artificially. 每一元素都有放射性同位素，或是天然存在的，或是人工激活的。 These problems are still of primary concern to present-day physicists. 现代物理学家对这些问题仍然非常关心。 第1节 翻译练习18 Manual fire alarm station are installed on each floor at the stairs to be used for fire notification by the building occupants 每层楼的楼梯处装有手动消防警报器，便于楼内住户通知火情。 It all helps the claim that the raw material for life was imported from the clouds of space. 所有这些都有助于说明形成生命的原料是从星际空间的尘云输入的。 第1节 翻译练习19 This muscle “balancing” can help posture and promote more efficient movement. 这种肌肉的“平衡性”能帮助校正姿势，促进更有效的运动。 Being a good insulator, rubber strongly resists current flow. 橡胶是一种良好的绝缘体，它能基本组织电流的通过。 第1节 翻译练习20 The ability to control your quality level is important for desktop video producers. 控制品质水平的能力对桌面视频制作者是十分重要的。 Internal heat, trapped by the gases, fired up a protosun and ignited thermonuclear reactions. 被气体封住的内部热量点燃原始太阳，激起热核反应。 第1节 翻译练习21 There are two different kinds of electricity, which we call positive electricity and negative electricity. 电有两种：正电和负电。 There are different forms of energy: heat energy, light energy, sound energy, mechanical energy, electrical energy, etc. 能有各种不同的形式：热能、光能、声能、机械能和电能等。 There are two groups of metals: pure metals and their alloys. 金属有两大类，纯金属及其合金。 第1节 翻译练习22 Mathematics has the same educational function as classics used to have. 数学现在所起的教育作用和过去古典著作一样。 Copper has very high conductivity. 铜的导电率很高。 When you turn a light or electric appliance off, there will be electric voltage built up at the switch, but no current will flow. 当关上电灯或者电器时，在开关上有电压产生，但是没有电流流动。 It is a set of programs governing the way in which multimedia files are created and displayed on the Internet. 它是一套程序，这些程序控制着因特网上多媒体文件的建立和展示的方式。 第1节 翻译练习23 In this book I have given special prominence to the laws that govern gravity. 在这本书里，我特别强调了那些支配引力的定律。 A brief description of how transistors are manufactured is given here. 这里扼要地讲讲晶体管是如何制造的。 This type of spring is extensively used in electrical instruments, and deserves special consideration. 这种弹簧广泛地应用于电工仪表中，因此值得专门地考察一下。 In copper and most pure metals there is an appreciable increase in resistance with an increase in temperature. 在铜和大多数纯金属里，随着温度的升高，电阻也会明显地增大。 When a new or repaired machine is about to be put into service, a thorough examination for mechanical defects cannot be cancelled. 一台新机器或修好的机器投入使用时，必须仔细地检查有无机械缺陷。 What worries nuclear physicists is the safe disposal of nuclear waste. 令核物理学家担忧的是如何安全地处置核废料。 第1节 翻译练习24 In order to keep the engine speed within the limits which it was designed for, a device which is known was a governor is incorporated in the engine. 为了把发动机的速度保持在设计的范围之内，发动机内装有一个叫做限速器的装置。 Only a few metals are used commercially in their pure state. 只有少数几种金属以纯态被用在工商业上。 The heat supply was inadequate to maintain the liquid as its boiling point. 热的供给不足以使液态保持在其沸点。 第1节 翻译练习25 Quasi-stars broadcast powerful radio waves which may vary in strength. 类星体不断发出强大的无线电波，其强度可能各不相同。 Induction motors are simple in design, sturdy in construction. 感应电动机设计简单，结构牢固。 Above a certain critical temperature, steel will change in structure. 超过某一临界温度，钢的结构便会发生变化。 第1节 翻译练习26 In the atmosphere, the ratio by weight of the nitrogen and oxygen varies slightly about an average of 3:2:1. 大气中的氮和氧按重量的比例平均约为3:2:1。 The temperature coefficient of the resistance is positive for metals and negative for semiconductors. 金属的电阻温度系数的正的，而半导体的是负的。 第2节 翻译练习1 The indifference curve had no curvature at all. 无差异曲线根本没有弯度。 The inactive gas neither burns nor supports combustion. 惰性气体既不能燃烧，也不助燃。 Cast iron is not easily repaired by welding or brazing. 铸铁（制品）不易用熔焊或钎焊法修复。 Blowing method is no longer possible, especially in the case of thick work pieces. 尤其是厚工件，已不可能采用喷吹法。 第2节 翻译练习2 Computers are not well suited to manipulate pictures or other graphic data. 计算机不很适合于处理图像或其他图示数据。 Friction is not only undesirable. 摩擦并非总是不需要的。 An elastic material does not necessarily obey Hooke’s law. 并非任何一种弹性材料必定符合胡可定律。 第2节 翻译练习3 Such glass would bend like metal when dropped rather than shatter bits. 这种玻璃掉在地上会像金属一样弯曲而不碎裂。 This machine appears to be out of order. 这台机器似乎不正常。 A quick reality check confirms that the computer, far from reducing the amount of paper, has actually increased it. 实际情况明显反映出计算机不仅没有减少纸张用量，相反却使之增加。 The speed and versatility of the earliest computers were greatly inferior to those of a modern microcomputer. 早期计算机的速度和通用性远不如现代的微型计算机。 第2节 翻译练习4 Despite its many advantages, wood are not without its drawbacks as a fuel. 尽管木材有许多优点，但作为燃料不是没有缺点的。 Without substance, there could be no world. 没有物质就没有世界。 No flow of water occurs unless there is a difference in pressure. 没有压差，水就不会流动。 In the absence of electricity, large scale production is impossible. 有了电才可能进行大规模生产。 All these electric protective devices should not be unboxed or unwrapped until the moment for fitting has arrived. 要等到安装这些电气保护装置时才可打开包装箱或包装盒。 第2节 翻译练习5 There are few to support the view that in a highly efficient transit operation almost every vehicle should be capable of running almost every service. 很少有人赞成这样的观点，即在高效的交通运输作业中，几乎每一种机动车都应能够完成几乎所有的服务功能。 They found that the ozone damage over the Arctic was much less severe than the damage over the South Pole and that there was little increased risk to people living in the far north. 他们发现，北极臭氧层的破坏远不及南极厉害，这使得生活在北极地区的人们几乎没有增加危险。 第2节 翻译练习6 No significant difference between the experimental and control birds was observed. 没有观测到实验鸟和对照鸟之间存在明显的差异。 The object did not move because it was pushed. 该物体移送，不是因为有人推了它。 The circuit should be overloaded on no conditions. 电路在任何情况下都不得过载。 Even in the South Pole, no actual (hole) exists. 即使在南极也不存在实际的（臭氧）“空洞”。 We don’t think it only a hypothesis. 我们认为那不仅仅是一个假设。 We don’t consider that neutrons have charges. 我们认为中子不带电。 At no time and under no circumstances will they be the first to use nuclear weapons. 他们在任何时候和任何情况下都不首先使用核武器。 总复习题 He ascribed this disagreement to the oversimplified model. 他把这种不一致现象归因于模型过于简单。 Now iron and steelmaking processes are now reexamined worldwide. 现在世界范围内开始重新审视炼铁和炼钢工艺。 This disease is responsive to treatment with drug. 药物治疗这种病有良好的疗效。 Distilled water is needed in the laboratory in large quantities. 实验室里需要大量的蒸馏水。 Safety precautions should be observed at all times. 任何时候都应遵守安全预防措施。 The wing has a flat undersurface and a curved topsurface. 机翼的下表面是平的，上表面是弯曲的。 There exist many sources of energy, both potential and kinetic. 势能和动能都有许多来源。 In the sky, many planetary systems must be entirely lifeless. 天空的许多行星系必定是无生命的。 If the needle fails to remain at zero, readjust control No.1. 若果指针不能保持在零的位置上，应重新调整一号控制器。 The earth was not believed to be round but flat. 人们曾经认为地球是扁的而不是圆的。 Not enough power can be got out of the single-stage socket to get the satellite up to where it should be. 从单级火箭上不可能获得足够的功率把卫星送到所需的位置。 第10章 第1节 翻译练习1 We could use two resistors in series, or we could increase the value of the present single resistor. 我们可以用两个串联的电阻，或者我们可增加现有的一个（电阻）的电阻值。 Displacement is a vector and time is a scalar. 位移是一种矢量，而时间是一种标量。 Industrialization enables countries to raise their standards of living, but it is also necessary to improve methods of agriculture as well. 工业化能使国家提高其生活水平，但是也必须改进农业生产方法。 第1节 翻译练习2 The temperature would have continued to go up but that feedback took place. 要不是发生反馈的话，温度会继续上升。 The average kinetic energy of the molecules is increased and the temperature is raised. 分子的平均动能增加了，因而温度也升高了。 The output power can never equal the input power, for there are always losses. 将铅化合物加进汽油中以提高其辛烷值，从而也提高了发动机的性能。 第2节 翻译练习1 Where this new tool of investigation will ultimately take us is beyond my powers of prediction. 这一新的研究工具最终将把我们带至何方，我无法做出预测。 A more carefully prepared experiment would be possible to confirm your theory. 更加精心准备的实验有可能证实你的理论。 Whether life can exist on any planet other than the earth is very doubtful. 除地球外的任何别的行星上是否存在生命，是很值得怀疑的。 第2节 翻译练习2 It is likely that all the powder will dissolve at once. 全部粉末可能一下子全部溶解。 It is no longer a necessary consequence that an object thrown into the air must fall back to earth. 射入空中的物体一定会回到地面上来，这已不再是必然的结果。 It is quite natural therefore that all modern machines should preferably employ continuous rotary motion instead of periodic reciprocating motion. 所以，现有现代机器都尽量采用连续的回转运动来代替周期的往复运动，这是很自然的。 It is still to be discussed where the new substation will be built. 新变电站建在什么地方仍有待讨论。 第2节 翻译练习3 We use insulators to prevent electrical charges from going where they are not needed. 我们使用绝缘体来防止电荷跑到不需要电荷的地方去。 Faraday and Henry were trying to discover whether electricity could be produced from magnetism as a magnetic field was produced by an electric current. 法拉第和亨利都曾试图揭示，电是否可像磁场由电流产生那样由磁产生。 One might ask why the scientist feels so certain of the existence of these particles. 人们可能要问，科学家对这些粒子的存在为什么感到如此肯定。 第2节 翻译练习4 On the moon an astronaut will weigh only one sixth of what he weighed on earth. 宇航员在月球上的体重只有在地球上体重的六分之一。 We feed the program and the data into an input device, from where they are taken, through the control unit, into the store. 我们将程序和数据送入输入设备，从那里通过控制器把它们送入存储器。 第2节 翻译练习5 The consequence of heating a given copper rod is that it undergoes oxidation and forms an oxide. 加热一条铜棒的结果是它会氧化并形成一种氧化物。 The cutting speed of the tool is what matters. 刀具的切削速度才是重要的。 The assembly-line of the factory is where all the components are put together. 工厂的装配线是将所有的零部件装在一起的场所。 The first thing we need to find out is whether water contains air. 我们需要弄清楚的第一件事是水是否含有空气。 第2节 翻译练习6 At the end of last century, an important discovery was made, that everything was partly built of electrons. 上世纪末有一个重要发现，即一切东西都有一部分由电子组成。 In 1905 Einstein worked out a theory that matter and energy were not completely different things. 1905年，爱因斯坦提出了一个理论：物质和能并不是完全不同的东西。 第2节 翻译练习7 The proposal that more equipment should be imported from abroad is to be discussed at the meeting. 会上将讨论从国外进口更多设备的建议。 The problem that all machines in this factory must be controlled by computers will be solved before long. 该厂所有机器实现计算机控制的问题，不久就能解决。 第2节 翻译练习8 At that time, only a few scientists accepted the idea that there had been a large island in what is now the deepest part of this sea. 那时，只有少数几个科学家认为现在的这个海域最深的部分曾经有过一个大岛。 An outstanding advantage is the fact that the axial clearance is not limited. 其突出的一个优点就是轴向间隙不受限。 We were working on the supposition that they could improve the complex machine. 我们认为他们能改进这台复杂的机器。 第2节 翻译练习9 Some necessary measures were adopted in view of the fact that the event had happened unexpectedly. 由于事态的意外发生，我们采取了一些必要的措施。 Despite the fact that you are not the only person to blame, you are principally responsible for it. 你虽然不是唯一承担过失的人，但你要负主要责任。 第2节 翻译练习10 Obviously there was little probability that they would succeed in electrolysis. 很明显，他们在电解方面成功的可能性是很小的。 There is no certainty that the elastic material does not necessarily obey Hooke’s law. 人们不能确定，这种弹性材料是否符合胡可定律。 There are also suggestions that black holes could be used to create bombs in the future, by amplifying radio waves sent up to them. 还有一些建议，认为通过把发射到黑洞的无线电波增强，将来有可能利用黑洞制造炸弹。 第3节 翻译练习1 It is particularly useful for aspheric optics production where ordinary polishing kinematics is totally unsuitable for aspherics. 它特别适用于加工传统机械抛光无法做到的非球面光学产品。 Cloning doesn’t necessarily make cells grow old, and can even act as a fountain of youth, say researchers who have been investigating a group of cloned calves. 克隆牛犊的研究者们宣称：克隆不一定非使细胞老化不可，它甚至可以成为长生不老的源泉。 A system that mimics photosynthesis efficiently may be 50 years away. 一种能有效地模拟光合作用的系统的出现可能还需要50年。 第3节 翻译练习2 They rapturously commended the faultless organization of the aerial site and the skill of Eiffel’s engineers who, amongst other achievements, had perfected a special design of crane (Guyrnet type) that moved vertically along the lift rails. 他们兴高采烈地赞扬高空作业工地无懈可击的组织工作和埃菲尔铁塔的工程师们高超的技术。这些工程师的成就之一是完善了一种特殊设计的起重机（居耶钠型），这种起重机能沿着升降机轨道垂直移动。 As reported recently in Science, researchers at the University of Notre Dame are working on a method of building circuits that need only a tiny initial electrical charge to transfer information. 根据《科学》杂志最近的报道，诺查丹玛大学的研究人员正在开发一种电路设计方法，它只需微量的初始电荷便可以传输信息。 The sound to be recorded is picked up by a microphone which transforms sound waves into impulses of electric current. 所要记录的声音为传声器所接收，后者将声波转变为电流脉冲。 Already laser guns are being developed which could kill an enemy, or bring down an airplane or a missile at a great distance. 人们已在研制各类激光炮，这些激光炮能远距离杀死敌人，击落飞机或导弹。 A thermometer is a tube closed at both ends which contains a liquid. 温度计是一根两端密封，里面装有某种液体的玻璃管。 The sun gives us heat without which the earth would be a frozen world in which no life can exist. 太阳给我们提供热，没有这种热地球将会成为生命无法生存的一个冰冻的世界。 第3节 翻译练习3 Laser is the most powerful drilling machine, because there is nothing on earth which cannot be drilled by it. 激光器是打孔能力最强的钻机，因为它能给世上的任何物体钻孔。 There are many substances through which currents will not flow. 许多物质不导电。 However, there are many instances where additional tests are needed. 可是，在很多情况下需要进行附加测试。 第3节 翻译练习4 In a domino-like effect, the charge of the first of the first cell in the circuit charges all the cells that follow. 好像多米诺效应一样，电路中第一个电池的电荷能够使后面所有的电池充电。 A good understanding has been obtained of evaporation processes which are carried out at ordinary pressure. 人们对于常压下的蒸发过程已有了清楚的了解。 In the early days of the clipper ships, sailors who went on long voyages would often get a dangerous disease called scurvy. 在使用快速帆船的初期，远洋海员们往往会患一种叫做坏血病的危险疾病。 The hardness of the steel depends on the percentage of carbon it contains. 钢的硬度取决于其含碳量。 第3节 翻译练习5 A common complaint of travel agents is that Europeans, who account for over 40 percent of the tourist traffic, expect to see all of India in a fortnight in the same way that they may try to see Italy or France in a week. 旅游业经理的共同抱怨是：占游客总数百分之四十以上的欧洲人希望能有在一周内游览意大利或法国的那种方式，在两周内游览全印度。 The result, which have just been reported to Britain’s Medical Research Council, show that some of the divers who were apparently healthy had areas of brain damage similar to those found in stroke victims. 最近提交给英国医学研究委员会的检查结果报告表明：这些潜水员中有些人虽然表面上看起来很健康，但脑部有些区域出现同中风病人类似的病灶。 第3节 翻译练习6 For heavy multi-storey blocks built on poor soil, the foundation often consists of a watertight reinforced concrete open box, which also forms the basement. 若要在土质差的地方建高层建筑，经常采用不渗水的混凝土箱型基础，它也是地下室的一部分。 When a crystal melts, disorder is produced in the particles, which lose their fixed locations in the crystal lattice. 当一种晶体熔化时，粒子中便产生无序现象。这些粒子便失去其晶格中的固定位置。 Mass is to be distinguished from weight, which is measured by the pull of gravity on a body. 应把质量与重量区分开，后者是根据对物体的引力来测定的。 The transistor is a current-controlled device, as distinct from the vacuum tube, which is a voltage-controlled device. 晶体管是一种电流控制器件，它不同于真空管，后者是电压控制器件。 第3节 翻译练习7 The sun heats the earth, which make it possible for plants to grow. 太阳使地球变暖，这使植物生长成为可能。 A nation’s level of development can measured by its ability to produce food and fiber, which relates to their expertise in the area of Crop and Soil Sciences. 一个国家的发展水平可以通过它生产食品和纤维制品的能力来衡量，这涉及到其在作物与土壤学领域的专门技术。 Liquid water changes to vapor, which is called evaporation. 液态水变为蒸汽，这就叫做蒸发。 第3节 翻译练习8 World population is increasing at a rate with which food and other production may not be able to keep place. 世界人口在迅速增长，使得粮食和其他产品可能无法跟上其增长的速度。 The drill should be backed from the work frequently, which allows removal of chips and passage of coolant. 应经常后退钻头，以便能除去钻屑并使冷却液通过。 And at the same time they would foil gene pirates, who would see their stolen goods disappear before their very eyes. 同时还能挫败基因窃贼，因为他们会眼睁睁的看着他们偷来的东西就在眼前消失掉。 Strontium is named for Strontian, a Scottish village, where ore containing is was found. 锶是以一座叫做斯特朗西恩的苏格兰村庄命名的，因为含锶的矿石就是在那里发现的。 Cancer should be suspected in persons who have any of these symptoms and signs for unaccountable causes and for an unreasonable period. 如果病人具有任何这些症状和体症，病因难以说明，而且持续时间过长，就应怀疑病人换了癌症。 第3节 翻译练习9 Even if our measurements show the same velocity over different sections, it may be asserted that the motion is uniform only with the degree of accuracy that the measurements were made with. 虽然自动化机器有很多优点，但它们只能做人们吩咐它们要做的事。 The interpretation, which is not entirely convincing, is at least partly true. 这种解释虽不完全令人信服，至少有几分真实性。 Anyone who has tugged heavy hand baggage down endless airport corridors, or waited for a delayed flight in a sterile lounge will know how user-unfriendly many airports are in design terms. 任何人当他拖着沉重的随身行李，走过无止境的机场走廊，或者在枯燥乏味的休息室里等候延误的班机，都会体会到许多机场在设计上对旅客是多么不方便。 第3节 翻译练习10 The facts of science are not, as some think, dry and lifeless. 与某些人想象的相反，科学上的某些事实并不是那样的枯燥无味和没有生命力。 The patient did not have a heart attack as the doctor had feared. 与医生担心的相反，患者并没有复发心脏病。 第3节 翻译练习11 Glaxo Wellcome is developing a method of vaccine delivery where the vaccine is attached to tiny gold particles. 格莱索·威尔克姆正在开发一种疫苗释放方法，即将疫苗粘附在微金粒上。 Astronomers and scientists think that a black hole is a region of space (not a thing) into which matter has fallen and from which nothing can escape——not even light. 天文学家和科学家认为黑洞不是一种物体，而是太空的一个区域，即物质掉进去后，任何东西，甚至于光，都无法逃出。 第3节 翻译练习12 Episodes of low cardiac output which were accompanied by significant increases in PAP/AOP ratio occurred in 20 patients and were managed by alteration and administration of pulmonary vasodilators. 在20个患有低心输出血量发病的患者中，伴有肺动脉压和主动脉压比率明显增加，其处理方法是改善通气并给以肺血管扩张剂。 The ceramic will be made of oxide powders, using techniques that must be carried out only in an atmosphere of ultra-pure and inert nitrogen. 这种陶瓷用氧化物粉末制成，所采用的工艺必须在超高纯度和超高惰性的氮气中才能进行。 New evidence to be published later this month in the journal Science offers a simple explanation why two laboratories came to claim credit for the same discovery. 本月晚些时候将在《科学》杂志上公布新的证据，就为什么两个实验室对同一个发现都要求 荣誉权的问题提供一个简明的解释。 第3节 翻译练习13 Putting a restriction on the depth to which a diver can descend might be helpful. 对潜水员下潜的深度实行限制也许是有益的。 Nowhere in the whole domain of the motions of the natural world have we yet found any case to which the analysis of mechanics does not apply. 在自然界的整个运动领域里，我们还没有发现力学分析不适用的任何情况。 This is an incandescent bulb, the light of which travels in all directions. 这是一盏白炽灯，它的光是向四面八方传播的。 Some elements are known, the atoms of which usually do not combine with more than tone atom of any other element. 某些元素是众所周知的，这些元素的原子通常不能同其他任何元素的一个以上的原子相结合。 Air is a mixture, the components of which are of great use in the chemical industry. 空气是一种混合物，其成分在化学工业中大有用处。 第4节 翻译练习1 As we observe objects around us, one of the most noticeable properties is their motion. 当我们观察周围的物体时，最显著的特性之一是其运动性。 When an object is suspended by a single string, it is observed that the string hangs vertically. 当一物体用一根细绳悬挂起来时，可以看到绳子垂直的挂着。 When one form of energy disappears, other forms appear in equivalent amounts. 每当一种形式的能量消失时，就会出现等量的其他形式的能量。 第4节 翻译练习2 Our whole physical universe, when reduced to the simplest terms, is made up of two things, energy and matter. 我们的整个物质世界，如果用最简单的话来说，是由两样东西组成的，即能和物质。 We are always able to know the third one when we know the magnitudes of the other two. 如果已知其中的两个变量，我们就可以求出第三个变量。 第4节 翻译练习3 A body at rest will never move till a force compels it. 精致的物体在外力迫使它运动之前决不会运动。 Heat and temperature were confused until Joseph Black cleared up the subject in 1760. 在1760年约瑟夫·布莱克澄清了热和温度这个问题以前，人们一直将两者混为一谈。 Slide line C to the left, until it corresponds with line D. 将线C向左平移，直到与线D重合为止。 Boil the solution till it becomes free of H2S. 将该溶液一直加热到没有硫化氢为止。 Electric current does not flow in the circuit until we add a battery. 直到我们加上电池组后，电流才能在这条电路中流动。 第4节 翻译练习4 Once a satisfactory system of lubrication has been secured, the hardness of the interacting elements becomes critical. 一旦获得了满意的润滑系统，相互作用的元件的硬度就成为了关键因素。 Once airborne particles touch each other, they combine into a bunch of particles. 空气中的粒子一旦彼此相碰，就结合成一个粒子团。 If all the impending forces of gravitation and resistance could be removed, there is no reason why the ball, once it is in motion, should ever stop. 如果一切起阻碍作用的引力和阻力能被除去，就没有理由认为，球一旦处于运动中会再停下来。 第4节 翻译练习5 Since the arc burns in a closed volume, a high gas pressure will be obtained. 因为电弧在一个密闭容器中燃烧，将得到很高的压力。 Since from now on frequent reference will be made to sample and population, it is necessary to distinguish between the mean of a sample and the mean of population. 因为从现在起要常常提到样本和种群，所以有必要把样本和种群的均值区分开来。 The results of the investigation were not conclusive since the crucial experiment had been performed only once. 研究的结果还不是结论性的，因为决定性的实验只进行过一次。 第4节 翻译练习6 Where there is no need for electrical isolation an auto-transformer is sometimes employed. 在不需要电绝缘的地方，有时使用自耦变压器。 Where only small a variation in output is required, synchronous tap changing is often used. 在要求输出电压调节范围较小的电路中，常常采用同步抽头变换法。 第4节 翻译练习7 Where the bearing capacity is particularly poor or the quality of the soil varies considerably, a raft foundation is often recommended to support normal buildings. 若承载力特别低或土质差异巨大，通常用片筏基础支撑一般的建筑物。 Concrete foundations need not always be reinforced, but where the load to be carried is high and the veering capacity of the soil poor, heavy reinforcement is usually necessary. 混凝土基础不必总是用钢筋来加固。但是，若承受的载荷很大，而且地基的承载力又比较低，通常有必要用钢筋进行大力加固。 第4节 翻译练习8 Computer technology is advancing so rapidly that no book can ever be fully up to date. 计算机技术发展非常迅速，所以任何时候也不可能有一本书能及时充分的反映它的最新成就。 Gears play such an important part in machines that they have become the symbol for machinery. 齿轮在机器中起着相当重要的作用，以致它已成为机械的象征。 The bar is set next to a screw, so that it touches the screw when it is straight. 金属棒安装的位置紧靠着螺钉，这样，当金属棒伸直时就碰到螺钉。 第4节 翻译练习9 In order that electrons be accelerated in an applied field, they must be able to move to higher energy levels. 为了使电子能在外加场中加速，电子应能移到更高的能级。 The belt is adjusted so that it will fit tightly over both wheels. 为了减少摩擦，金属表面必须涂上润滑脂。 The complier must know its operation code and its parameter so that an instruction can be assembled. 为了能储存大量电荷，电容器通常用大面积的金属板制成。 Negative work should be maintained at as low a value as possible for any given pressure ratio, in order that a maximum amount of useful work may be obtained. 在给定的压力下，负功应尽可能维持在低的数值下，以便获得最大的有用功。 I am going to start up the generator in case the power goes off. 我去启动发电机，以免断电。 Set all screws so they bear evenly on leveling plates. 调整各个螺钉，使它们都均匀的压在调平板上。 第4节 翻译练习10 The pressure of a gas is inversely proportional to its volume if its temperature is kept constant. 如果温度保持不变，则气体压力和体积成反比。 As long as the current flows, the armature will keep rotating. 只要有电流流通，电枢就会不停的转动。 An observer will not see a rainbow unless there are drops of water suspended in the air. 如果没有小水滴悬在空中，观察者就看不到彩虹。 The law is true provided that the physical conditions of the circuit remain constant. 当电路的物理条件不变，这一定律就是正确的。 If the admissible gripping force is exceeded, a hydraulic overload protection is operated. 当夹紧力超过了允许值，液压超负荷防护装置就会起作用。 We can keep the steam engine at work, so long as we have means of producing heat. 我们能够使蒸汽一直运转，只要有办法产生热。 第4节 翻译练习11 Electricity flows through a wire just as water flows through a pipe. 电流通过导线，正像水流通过管道一样。 Exotic plastics, glass and ceramics will shape the future just as surely as have genetic engineering and computer science. 奇异的塑料、玻璃和陶瓷无疑将同遗传工程和计算机科学一样塑造着未来。 Solids expand and contract as liquids and gases do. 固体像液体和气体一样地膨胀和收缩。 第4节 翻译练习12 Although these particles are very light, their energies are considerable because of their high speeds. 虽然这些粒子很轻，但由于速度很快，因而能量很大。 Even if someone is not a programmer, he can have a great impact on piece of software by suggesting how to improve it to the development team. 即使一个人不是专业编程人员，他也可以通过向开发小组提出改进建议，而对一个软件产生极大的影响。 While the stars look like mere specks, they are in reality enormous bodies. 虽然看起来只是些光点，实际上星星都是庞然大物。 Though a little over 100 elements in nature, they combine to form thousands upon thousands of different substances in the world. 虽然在自然界中只有100多种元素，可是它们却构成世界上成千上万种物质。 No matter how small a stress is applied to a body, the body will yield a little. 作用在一物体上的应力无论多么小，该物体总会有一点变形。 第4节 翻译练习13 Virtual convergence will take the power on your desktop and make it available wherever you want it. 这种放大器无论信号变化怎样缓慢，都能放大输入信号。 The unique training of the chemical engineer becomes essential in these areas whenever processes involve the chemical or physical transformation of matter. 只要工艺过程涉及到物质的化学或物理转换，就必然要专门培训化学工程师。 第4节 翻译练习14 It is anticipated that LSI chips will show twice as high a reliability as they have now. 预计大规模集成电路芯片的可靠性比目前可提高1倍。 The electrons meet less resistance when conductor is cold than when it is hot. 导体冷的时候，电子遇到的阻力比导体热的时候小。 Electronic engineers are more interested in the application than in the development of semiconductor devices. 电子工程师对半导体器件的应用比对半导体器件的研究更感兴趣。 第5节 翻译练习1 We believe that the ratio is modest hypercholesterolemia since individuals with low or very high cholesterol concentrations are unlikely to have their risk of developing CHD (coronary heart disease) altered either by HDL-C measurement or the calculation of the ratio. 我们认为这一比率只适用于血胆固醇有些过高的病人，因为胆固醇偏低或过高的人得冠心病的可能性不大会因为他们的高密度脂蛋白胆固醇的高低或这一比率的大小而有所改变。 Now, a team of astronomers has discovered evidence that the object, whatever it may be, is spewing vast quantities of energetic particles that collide with a surrounding irregular ring of cold hydrogen gas. 现在，一组天文学家已经发现了证据，即这个天体（不管它是什么），在不断地喷出大量高能粒子，同周围的形状不规则的冷氢气环相碰撞。 However, in cases that had episodes of increased PAP/AOP ratio, the mean duration of function was increased to five days, and this was almost certainly related to the use of continuous tolazoline infusion through the catheter. 然而，在患有增加肺动脉压和主动脉压比率的病例中，平均效用时间增加到五天，这几乎肯定与通过导管继续输入抗肾上腺素有关。 第5节 翻译练习2 Just as a pace satellite, once it has got away from the pull of the earth’s atmosphere, continues to circle round and round the earth for ever, so an electric current circling a frozen ring of mercury should continue to flow for ever, if the temperature is kept below the essential four degrees above absolute zero. 如果把冷冻的水银环的温度保持在低于绝对零度以上4度的话，环绕水银环流动的电流就必定会不停的流动。正如人造卫星一旦摆脱地球大气的引力，就会永远绕地球运行一样。 It is very interesting to note the differently chosen operating mechanism by the different manufacturers, in spite of the fact that the operating mechanism has a major influence on the reliability of the circuit-breakers. 尽管操作装置对断路器的可靠性具有主要的影响，但注意不同的制造厂按不同形式选择操作装置非常有趣的。 Thus, marginal cost to the producer may fall below marginal cost from the point of view of the whole economy when extra output requires extra foreign exchange and when foreign exchange is particularly scarce. 以至当生产额外的产品需要额外的外汇，而外汇又很缺乏的情况下，生产者的边际成本可能低于从整个经济角度来看的边际成本。 第5节 翻译练习3 This development is in part a result of experimental studies indicating that favorable alterations in the determinants of myocardial oxygen consumption may reduce ischemic injury and that reduction in afterload may be associated with improved cardiac performance. 从某种角度上讲，这方面的进展是实验研究的结果。实验研究表明，心肌耗氧量的决定因素的改善可减轻局部缺血性损害，并且，负荷的减轻也能改善心肌功能。 Up to a point, flyovers and underpasses, being the first really decisive steps to speed up and diver traffic, have eased the situation, but a considerable contribution toward a satisfactory solution can be made by underground railway networks. 在某种程度上，立交桥和地下道的建设，在加速和分流交通方面迈出了具有决定意义的第一步，从而缓解了交通不畅的局面。但要从根本上解决交通问题，仍需依赖地铁系统。 In order to understand what happens during sintering of compacts, the changes in density, in dimensions, in metallographic structure and in mechanical properties during sintering must be studied from an experimental point of view, beginning with those in compacts from a single metal powder or from homogeneous solid solution alloy powders. 为了了解用单一金属粉末或同类固体溶解合金粉制成的压坯在烧结过程中发生的变化，必须从实验的观点研究烧结过程中压坯的密度、尺寸、金属结构和机械性能的变化情况。 第5节 翻译练习4 However, in our experience some patients, in whom a high pulmonary vascular resistance was successfully lowered by the above measures, have had episodes of increased pulmonary vascular resistance post-operatively accompanied by clinical deterioration, which in some cases was extremely rapid. 然而，根据我们的经验，通过上述措施，某些病人的肺血管阻力成功的降低了，但术后由于临床恶化并在某些病例中发展很快，所以仍有肺血管阻力增高的现象。 The nutritional dilemma of persons with AIDS, or PWAS, is that they must eat abundantly yet they must also avoid foodborne illness, juggle foods and medications, and surmount the poor appetite and indigestion caused by their medications and by AIDS itself. 艾滋病患者又称PWAS， 他们所遭遇的饮食困境表现为患者一方面必须大量进食，另一方面又不得不防范因饮食而导致的疾病，拒绝零食和用药，还要克服因治疗以及艾滋病本身而引发的食欲不振和消化不良。 What is questioned is whether a country like Britain has a chance, assuming it has the will, to succeed where so many have failed and even assuming that is has, should make the tremendous effort and take substantial financial risk of trying to leapfrog into leadership in entirely new technology or whether it should take the softer option of merely catching up with the rest of the industrialized world. 问题在于像英国这样一个国家，假定它有决心，是否在那么多的国家已告失败的情况下有取得成功的可能，即使有可能，是否应该做出巨大努力并冒相当大的财政风险，试图在完全新的技术领域跃居领导地位，或者是应该做较为轻松的选择，仅仅赶上工业世界其他国家。 总复习题 In the early days of the telegraph and the telephone, men observed that signals sometimes jumped the space between wires running next to each other. 在电报及电话发展的早期，人们注意到信号有时会跳过并行导线的空间。 To understand both sides of the question, some background on how energy is obtained from a nuclear reaction must be studied. 要理解这一问题的两个方面，必须研究有关如何由核反应获得能量的一些基本情况。 Voyager’s photographs may help explain how they (Neptune’s rings) formed. 旅行者号拍摄的照片也许有助于说明这些光环是怎样形成的。 If the water is heated, the particles move more quickly, which agrees with our theory. 如果把水加热，粒子运动就更快，这一现象是和我们的理论吻合的。 Radiant heat waves pass through a vacuum, but may be absorbed by bodies whose temperature is thereby raised. 辐射热波能通过真空，但能被一些物体所吸收，因而这些物体的温度便升高了。 And there was the possibility that a small electrical spark might accidentally bypass the most carefully planned circuit. 而且总有这种可能性——一个小小的电火花，可能会意外的绕过了最为精心设计的线路。 People see things differently in the light of the fact that they are materialists and idealists. 由于人们的观点有唯物、唯心之分，因而他们对事物的看法也就不同。 There was evidence that all atoms consists of a nucleus and electrons. 有证据表明，所有原子都由原子核和电子组成。 Generally speaking, we do not use materials in the form in which they occur in nature. 一般来说，我们并不用自然界中天然存在的那种形态的物质。 These motors are, as a rule, especially designed for the specific machines with which they are used. 总的来说，这些电动机是为使用它们的专门机器特别设计的。 A machine spindle has different speeds which the operator selects according to the work. 机床主轴有几种不同的速度，操作人员可以根据工件进行选用。 Now that we have examined several areas of natural science, perhaps it would be well to attempt to define science. 既然我们以考察了自然科学的若干方面，也许不妨可以试试给科学下一定义。 Since an ammeter must be placed in series with the circuit, the latter must be opened for insertion of the meter. 由于电流计必须与电路串联，故后者必须断开以插入电流计。 Many of them have more than one solid states, as in the case of phosphorus, which is known in three solid phase: black, more familiar red and yellow forms. 热是能的一种形式，这是大家都知道的。 A nuclear reactor gets energy from the loss in mass during the nuclear reactions, so we can consider mass a form of energy. 核反应堆在核反应期间由质量的损失而获得能量，因此我们可以把质量看作是能量的一种形式。 An automatic production line is excellent for the automotive industry, where thousands of identical parts are produced. 自动生产线很适用于汽车工业，因为那里生存成千上万个同样的零件。 If you are traveling forward in a train, surrounding objects outside appear to be moving backwards. 如果你在一列向前行驶的火车里，外面周围的东西好像是在向后移动。 Television equipment makes use of devices that can be considered optical because they depend on light rays for their operation. 电视装置所用的器件可看成光学器件，因为这些器件是靠光线来工作的。 If the laser drifts, an attempt should be made to scan the whole free spectral range as fast as possible. 如果激光漂移，则应尽快地尝试扫描整个自由谱区。 The adjustment must be repeated each time the vessel is changed. 每当更换容器时都要重新调整。 Each time the short circuit happens, the short circuit current runs the battery down. 每当短路发生时，短路电流就将电池的电能耗尽。 When pressure is applied to ice, part of it will melt. 假如对冰加压，一部分冰就会融化。 An object, once it is in motion, will persist in that motion because of its inertia. 物体一经运动，由于惯性就将继续保持其运动。 Seeing that heat can be used to drive machines, it is a form of energy. 由于热能够用来驱动机器，所以它是一种能。 The black stain usually occurs where parts are in contact with each other. 黑锈斑通常发生在零件相互接触之处。 In the subsequent years there was a trend of higher yields in tilled plots, although the increase was non-significant. 尽管在正常的情形下绝缘材料的性能很稳定，但在极端情况下，比如加压过高，高温或在某种化学物质作用下，绝缘材料的性能会遭到完全的破坏。 In general, there is a measurable difference in potential between the two electrodes whether the cell is passing a current or not. 通常，不论电池有无电流流过，两极之间均具有可测量的电位差。 It is evident that if in an oxygen converter carbon is replenished by continuous addition of coal and the exothermic combustion of carbon in the bath is balanced with the endothermic direct reduction of iron ore, and then the converter will be producing iron at a certain carbon content instead of steel. 很明显，如果在氧气转炉内碳是通过不断地添加煤来补充，而且熔池中碳的放热燃烧与铁矿吸热的直接还原相平衡，那么转炉可以生产含一定碳的铁而不是钢。 As shown by Sumitomo Metals the processes are not restricted to bottom blowing and a combination of top and bottom blowing is most likely to be chosen especially as post combustion of the CO is a most important possibility for the future. 住友金属公司的工作表明，这种工艺不仅局限于底吹，而且将来使一氧化碳产生二次燃烧成为最大可能时，组合式的顶一底吹会成为首选工艺。 The study of the chemical sensors was mainly concentrated on the subjects of selectivity, life, and cost; i.e. how to detect a specific material from the environment where many different substances co-exist (selectivity); how to maintain the sensor in the original condition (life); and how to economically achieve the targets (cost). 化学传感器的研究主要集中在选择性、寿命和成本上，即如何在很多不同物质共存的环境中测定某一特定物质（选择性）；怎样把传感器维持在初始状态（寿命）；怎样经济地实现目标（成本）。 The understanding of the mechanisms involved in the selectivity and reversibility of the sensors would be an interesting subject because it relates to a phenomenon of life, like crown ether and Valinomycin which are the simulation of the biologically selective membrane, the selection of the enzyme, microorganisms, anti-body, and organelle immobilized. 有关传感器的选择性喝可逆性机理的研究与了解将会是一个有趣的课题，因为它与生命现象有关：像王冠以太和结氨霉素，它们就是生物选择膜的模拟，也就是酶、微生物、抗体和细胞器官固定膜的选择。 Deformation is affected by the stress inherent in the metal, the microstructural characteristics of the starting material, the temperature at which the deformation occurs, the rate at which the deformation occurs, and the frictional restraint between the material being forged and the die surface. 变形会受到金属的内在应力、原始材料的微观结构特征、变形时的温度、变形的速度以及被锻造的材料与模具表面间的摩擦阻力的影响。 第11章 翻译练习1 The root systems of terrestrial plants perform two primary functions: one is the acquisition of soil-based resources (principally water and dissolved ions) and the other is anchorage. Other root system functions, such as storage, synthesis of growth regulators, propagation, and dispersal, can be seen as secondary. Little is known of the early evolution of the nonaerial parts of plants, but it is certain that most of the first land plants had poorly developed root systems. Such fragments as are preserved are of large diameter and sparingly and often dichotomously branched. Since early land plants were small and lived in very wet environments neither anchorage nor acquisition of water is likely to have been a serious problem. It is quite possible that the most difficult function for early root systems to perform was the acquisition of poorly mobile resources, especially photosphate. 陆生植物的根系有两个主要功能。一个是获得土壤养分的作用（主要是水分和溶解在水中的离子）。另一个是固定作用。根系的其他功能如贮存、生长调节剂的合成、繁殖和扩散则被看作是次要功能。我们对植物地下部分早期进化了解得比较少。但可以肯定的是，大多的早期陆生植物根系发育低。现存下来的早期陆生植物的根，直径大而分支较少，常是两叉的。由于早期陆生植物小且生活在非常潮湿的环境中，因此植物的固定和吸收水分都不可能成为严重的问题。很可能早期植物根系最难起到的作用是吸收养分，因为养分的移动性差，特别是吸收磷酸盐。 翻译练习2 Dies are usually made of cast iron. The dies should be split so that the cores and the casting can be readily removed, the cores preferably upwards so as not to interfere with gas heating of the die assembly from below. Where the die will not be tilted, sprues should be inclined, narrow, constricted at the bottom in front of the gate and arranged to fan out into the latter at an angle of 45 so as to avoid sharp corners. Several gates connected by a horizontal runner may be useful. 模具通常由铸铁制成。模具应制成可拆卸型，以确保方便地取出型芯和铸件。型芯最好朝上，以保证其不受在模具组建下方进行气体加热的影响。 模具在使用过程中不倾斜时，应在浇口前方底部设置倾斜，狭窄且缢缩的注入口，并使注入口以45度角展入模具底部，以避免出现急弯。有时可能用到由一条横浇道连起来的几个浇口。 翻译练习3 The suspensor used to be regarded merely as an anchorage device for the embryo, but it is now regarded as having an important role in the transfer of nutrients and plant growth regulators from the maternal tissues to the embryo. 过去人们将胚柄仅仅看作胚的固着器，但现在人们认为胚柄在把营养物质和植物生长调节因子从母体组织转移到胚中起着重要作用。当然在实验中对胚柄造成的破坏，影响胚的生长。在双子叶植物中，胚柄细胞经历了DNA内部复制，也就是DNA复制而核不分裂。尽管在植物界这是很普遍的现象，但胚柄代表了极端情况。例如，在红花菜豆的胚柄细胞中含有8192倍的DNA（即单倍体细胞中DNA的8192倍）。假定这些细胞最初是处于二倍体状态，这么大量的DNA意味着在核不分裂的情况下DNA复制12个周期。DNA内部复制的作用我们还完全不清楚。 翻译练习4 It was many hundreds of years before any further significant observations were made about the phenomenon of static electricity. Then it was discovered that many other materials besides amber could be charged by rubbing, which produced friction. A more important discovery was that there were two kinds of electrical charges. 数百年过去了，对静电现象的进一步观察才取得突破性成果。人们发现，除了琥珀之外还有许多其他材料也能摩擦起电。更为重要的发现了两种电荷的存在。 这两种电荷被称为正电荷与负电荷。正电荷用（+）号表示，负电荷用（—）号表示。这些符号今天仍然通用。人们还发现，同种电荷——同正或同负——相互排斥，而异种电荷——一正一负——则相互吸引。 人们更晚才知道，是一种叫做电子的物质微粒的移动引起电。电子三组成原子的一种微粒，而原子又是组成化学物质的基本单位。原子的中心是原子核，几乎包含原子的全部重量或者物质。原子核本身由两种不同的微粒，即质子和中子组成。 总复习题 Precision Forging Precision forging is normally taken to mean close-to-final form or close tolerance forging. In the final analysis it is not a special technology of its own, but a refinement of existing technologies to a point where the forged part can be used with little or no subsequent machining. The improvements cover not only the forging method proper, but extend to preheating, descaling, lubrication, and temperature control practices. 精密锻造 精密锻造通常指近终型锻造或小公差锻造。归根到底，它本身不是一项特殊的技术，而是对现有技术的改进。它生产的锻件很少经过或不经过后续加工就可以直接使用。这种改进不仅包括锻造方法本身，而且扩展到预热、除鳞、润滑和温度控制等。 是否使用精密锻造技术主要取决于附加锻造操作以及用刀具和取消机械加工之间的相对经济性问题。由于刀具开发的成本较高，精密锻造通常仅限于要求产品质量很高的生产中。 一个使用精密锻造的例子是涡轮叶片，现在它是用不锈钢和其他难以锻造的合金制造的。因为轻的叶片连接在相对重的基体上，涡轮叶片的形状不是特别适合于锻造。必须进行延长预变形，为实现此目标可以采用不同的生产方法。有的制造者通过镦粗其一端的方法生产，还有的挤压足够的材料形成叶片，但是在每种情况下，最后的模槽都是用于提高表面质量和保证较高的尺寸精度。 Antifriction Bearings Antifriction Bearings operate with rolling elements (either balls or rollers), and hence rolling resistance, rather than slicing friction, predominates. The cause of rolling resistance is the deformation of mating surfaces of the rolling element and the raceway on which it rolls. The three basic types of antifriction bearings are ball bearings, roller bearings, needle bearings. Ball and roller bearings can be designed to absorb thrust loads in addition to radial loads, whereas needle bearings are limited to radial load applications only. 滚动轴承 滚动轴承利用滚动体（滚珠或滚柱）来工作，因此占主导的是滚动阻力而非滑动摩擦力。滚动阻力的起因在于滚动体的配合面和它滚动的滚道的变形。滚动轴承的三种基本类型是：滚珠轴承、滚柱轴承和滚针轴承。滚珠和滚柱轴承在承受径向荷载之外还可承受轴向荷载，而滚针轴承仅限于承受径向荷载。 滚动（滚动接触）轴承的一个主要优点在于几乎完全消除了摩擦。因此，滚动轴承润滑剂的主要功能是帮助防腐及污垢污染。由于确实存在一定的摩擦，尤其是在滚动体与轴承座之间，润滑剂也必须带走这一滑动作用所产生的热，因此虽然有很小的摩擦，但是润滑剂仍然是必要的。 引起正常润滑的滚动轴承失效的原因是疲劳，它是发生在滚道的接触面或滚动体上的一种应力反向现象。这样，滚动轴承的寿命是以疲劳失效前轴滚动的转数来衡量的。轴承的载荷越大，其以转数为单位的寿命就越短。而且，轴的速度越快，轴承的寿命就越短。由于统计中要考虑到疲劳因素，所以也必须考虑失效的百分比概率。 了解各种类型的轴承的优点与缺点及它们的突出特点很有必要。例如，滚珠和滚柱轴承可以是自定位型以便调整轴的对中不准和偏移。此外，挡板及密封用于保护轴承以防外来污染物的污染。一些滚动轴承内装有密封好的润滑剂，这些润滑剂是由制造商提供的，使得轴承在整个使用过程中得到润滑。 In Situ Desulphurisation Partial removal of the sulfur values in fossil hydrocarbon fuels can be accomplished in place during the application of so called “in situ” recovery techniques. Perhaps the earliest of these techniques to be explored was in situ coal gasification. During the 1940’s and 1950’s, both the Russians and the British carried out extensive field trials with in situ coal gasification and demonstrated the practical feasibility of obtaining a low BTU gas product from the process. More recently in situ coal gasification trials have been conducted in Alberta and several projects in the Colorado oil shales have focused on in situ retorting of the shale to liberate the hydrocarbon. In situ recovery techniques using fire, steam flooding, or a combination of both, also appear to be one of the most practical routes for fluidizing the heavy bitumens of deeply buried oil sands thus enabling their recovery by drilled wells rather than mining. 现场脱硫 化石碳氢燃料所含硫的部分脱除可以在实施所谓的“就地”开采技术的过程中完成，这方面最早探索的技术大概是现场煤气化。在20世纪40和50年代，苏联和英国都进行了广泛的煤气化的现场试验，证明了此过程获得低BTU煤气产品的实际可行性。后来在亚伯达进行了现场煤气化实验。另外还有几项对科罗拉多页岩油的开发项目则集中研究对页岩油的现场提纯技术以产生碳氢化合物。采用燃烧、蒸汽注入或两者结合的就地开采技术也已经成为深层油砂中的重沥青流体化的最实际的技术途径，从而可以使用钻井法而不使用开矿法来开采这些沥青。 就脱硫而言，这种原地加工技术的最重要的优点大概在于可以达到需要的化学反应的温度和压力。如果在地面进行，则该温度和压力需要负责而昂贵的加工设备方能实现。这样可以就地实现化学反应状态，而如果将化石燃料开采出来以后再用传统的方法进行提炼精制，这样做既不切实际又不经济。在脱硫反应中这种高温高压条件特别重要。地面上的炼焦设备也许 可以模拟原地注入燃烧过程的氢转移反应，产生低分子量的碳氢化合物和硫化氢。因此，可以达到从有机硫化合物的母体中就地除硫的目标，而且可以出去更易于处理的气态H2S。 Seed Health Many pests and diseases are seed-transmitted; for example, the stem and bulb eelworm may be passed to the progeny via the see of Allium spp., while celery leaf spot can be transmitted by the infected seed. Many economically important plant viruses——for example, lettuce mosaic virus and tomato mosaic virus——are seed-transmitted. Virus in the seed or in the seed coat can lead to early initial field infection which spreads to other plants within the crop. 种子的健康 许多虫害和病害是通过种子传播的：例如茎线虫和球线虫可能通过葱属植物的种子传播，而芹菜叶斑病能通过感病的种子传播。从经济角度讲，许多造成很大经济损失的植物病毒，例如莴苣花叶病毒和番茄花叶病毒是通过种子传播的。种子内和种皮内的病毒能导致田间的初期感染，并在同种作物的其他植株间蔓延。 发展中国家的许多小规模种植者种植他们自己作物留的种子。他们常常忍不住从没有销路的作物中采集种子。此后导致下一代遗传特性差。小规模种植者不使用例如后代检测这样的技术。事实上，在一些国家许多大规模生产者也不使用这些相对简单的技术，因此种子改良的可能性，甚至维持原种水平的可能性有时也丧失了。 Nucleus The nucleus is usually more or less spherical, though nuclei with other shapes have also been observed. The nucleus is surrounded by and an envelope and contains the nuclear matrix and one or more nucleoli. 细胞核 尽管也观察到过其他形状的细胞核，但细胞核一般都是接近球形的。细胞核被膜包围着而且内含核基质和一个或多个核仁。在核质中有由脱氧核糖核酸和蛋白质组成的染色体。在染色体中对碱性染料有一定的亲和性的DNA和蛋白质的复合体称染色质。在分裂期间（核分裂之间）染色体解螺旋而且不能被分清。在这个阶段，在核质中常常可见到浓缩的染色深的染色质团。这种染色质称异染色质。比异染色质染色浅的染色质称常染色质。在分裂期间DNA合成，为染色体的复制过程做准备。核膜由两层单位膜组成。核膜之间狭窄的空间称核周腔。核膜和内质网相连。核膜上有一定规律地分布着的核孔。 本文来源：https://www.wddqw.com/doc/6298db53158884868762caaedd3383c4bb4cb4fd.html