专业英语习题解答.doc

1. When the cancer cells have invaded surrounding tissue or have spread through the blood or lymph to other parts of the body, complete removal becomes impossible.在癌症细胞感染了周围组织或通过血管或淋巴扩散到全身后就不能完全割除了。2. Factories everywhere are demanding for the new instruments with which it is possible to perform many experiments.各地的工厂都需要这种新仪器，用它能作许多试验。3. She obtain the honor by all students for her excellent teaching.她出色的教学水平赢得了广大学生的尊敬。4. Gases are frequently considered to incompressible.通常认为气体是可压缩的，而液体是不可压缩的。5. The ancients tried unsuccessfully to explain how a rainbow is formed. 古代人曾经试图说明虹是怎样产生的，但没有成功。6. There (in Germany)a group of amateur enthusiasts, inspired by dreams of inter- planetary travel, were conducting their own, occasionally fatal, experiments on liquid-fuelled rockets.德国有一些业余的火箭爱好者，在进行星旅行时的梦想激励下进行液体燃烧火箭实验，它们的实验有时是非常危险的。7. With the deve1opment of modern electrical engineering, power can be transmitted to wherever it is needed.随着现代电气工程的发展，人们能把电力输送到所需的的任何地方。8. Six medical scientists were honored in 1973 by the Gairdner Foundation of Toronto, Canada, for outstanding research.由于杰出的研究工作，六位科学家荣获了加拿大多伦多盖尔德纳基金的颁发的奖励。9. The first practical steam engine was invented by James Watt in 1776 . This is generally accepted as the beginning of the Industrial Revolution Then，the screw cutting lathe，invented by Henry Maudslay in 1797，became one of the first and most important of the power driven machine tools.第一个能够实际应用的蒸气机是由詹姆斯.瓦特在1776发明的，一般认为，那时候为工业革命的开始。亨利.莫尔兹在1797年发明的螺纹加工机床成为第一批重要的动力驱动的机床之一。10. In order to detect the time when a cutting tool should be changed，most modern machines are equipped with indicators that show the horsepower used during the machining operation When a tool becomes dull more horsepower is required for the operationwhich will show on the indicatorWhen this occursthe tool should he reconditioned immediately.为了知道什么时侯该换刀具，大部分现代机床都安装了指示器来显示切削加工所耗的功率。当刀具用钝时，加工就需耗更多的功率，并由指示器显示出来。一旦发生这种情况就应立即打磨刀具。11. All products that come cut of industry consist of at least one and often many types of materials. The most obvious example is the automobileA car contains a wide variety of materials, ranging from glass to steel to rubber, plus numerous other metals and plastic.工业生产的一切产品至少都是用一种，经常是许多种材料制成的。最明显的例子便是汽车，生产一辆汽车需用大量不同的材料，包括玻璃、钢材、橡胶以及许多其他的金属和塑料。12 The properties of a material originate from the internal structure of that material. This is analogous to saying that the operation of a TV set depends on the components and circuits within that setThe internal structure of materials involve atoms，and the way atoms are associated with their neighbors into crystals，molecules，and microstructures.一种材料的性能来自其内部结构。这好比说，一台电视机的运行依赖于电视机内部的零件和电路。材料的内部结构涉及到由原子和原子之间的相互关联而形成的晶体、分子和微结构。13 Characteristically，metals are opaque，ductile，and good conductor of heat and electricity Plastics(or polymers)，which usually contain light elements，and therefore have relatively low density，are generally insulators，and are flexible and formable at relatively low temperaturesCeramics，which contain compounds of both metallic and non metallic elements，are usually relatively resistant to severe mechanicalThermal，and chemical condition.从特点来看，金属不透明，有韧性、是热和电的良导体。塑料(聚合物)通常包含轻元素，因而密度较低，一般为绝缘体，并能在较低温度下弯折和成形。陶瓷是由金属和非金属元素的化合物构成，通常能抗恶劣的机械、温度和化学环境。14 Plastics and ceramics are nonmetals；however，plastics may be machined like metals, Plastics are classified into two typesthermoplastics and thermosets. The thermoplastics can be shaped and reshaped by heat and pressure but thermosets can not be reshaped because they undergo chemical changes as they harden. Ceramics are often employed by e11gineers when materials which call withstand high temperature are needed塑料和陶瓷是非金属。然而，塑料可象金属一样进行加工。塑料分成两类：热塑塑料和热固塑料。热塑塑料可通过加热相加压成形和再成形，而热固塑料却由于在硬化过程中发生了化学变化而不能再成形。工程师在需用耐高温材料时常常选用陶瓷。15 During the surface-grinding operations, heavy workpieces are either held in fixtures or clamped on the machine table by strap clamps and the like, whereas smaller workpieces are usually held by magnetic chucks.在表面磨削加工过程中，重的工件或者装在夹具上或者用压板或类似的东西压在机床工作台上，而小的工件通常用磁性卡盘装夹。16 Internal grinding is employed for grinding relatively short holes. as shown in Fig. 6. 3. The workpiece is held in a chuck or a special fixture. Both the grinding wheel and the workpiece rotate during the operation and feed is applied in the longitudinal direction.内圆磨削用来磨削想对较短的孔，如图6.3所示，工件被夹紧在卡盘或一个特殊的夹具上，在加工过程中，砂轮和工件都旋转，在纵向方向是作进给运动。17 Consequently, the peripheral velocity of the regulating wheel can be resolved into two components, namely, workpiece rotational speed and longitudinal feed. These can be given by the following equations.结果，导向轮的周向速度被分解成两个方向，即工件的旋转速度和纵向进给速度，它们可以用下面公式表示。18 The main dimensions of a grinding wheel are the outside diameter D, the bore diameter d, and the height H. These dimensions vary widely, depending upon the grinding process for which the wheel is to be used.砂轮的主要尺寸是外径D，孔径d和高度H，这些尺寸参数变化很大，它们取决于砂轮用于的磨削过程。19 As you may expect, the grain size of the abrasive particles(颗粒，微粒) of the wheel plays a fundamental role in determining the quality of ground surface obtained.正如你想的，砂轮颗粒的大小在决定获得的磨削质量起着决定的作用。20. Grinding makes use of abrasive particles to do the cutting Grinding operations may be classified asprecision or nonprecision，depending on the purposePrecision grinding is concerned with grinding to close tolerances and very smooth finish，Nonprecison grinding involves the removal of al where accuracy is not important.磨削利用磨粒来进行切削。磨削可根据不同的目的分为精磨和非精磨。精磨是为了紧公差和高光面修整的磨削，而非精磨是精确度要求不高的金属切削。21 The lathe is commonly called the father of the entire machine tool family，For turning operations，the lathe uses a singlepoint cutting tool which removes metal as it travels past the revolving workpiece. Turning operations are required to make many different cylindrical shapes，such as axes，gear blanks，pulleys，and threaded shaftsBoring. operations are performed to enlargefinish，and accurately 1ocate holes.车床通常被称为所有机床之父。在车削操作中，车床用个单刃切削刀具在旋转的工件上进行金属切削。车削用来切削出不同的圆柱形，如转轴、齿轮毛坯、滑轮、螺纹轴等。镗削用来扩大、精加工和加工精确定位孔。22 Minning removes metal with a revolvingmultiple cutting edge tool called milling CutterMilling cutters are made in many styles and sizesSome have as few as two cutting edges and others have 30 0r more. Milling can produce flat angled suffices，groves，slots，gearteeth，and other profiles，depending on the shape of the cutters being used.铣削用一个称为“铣刀”的旋转多刃刀具进行金属切削。铣刀有不同的式样和尺寸。有些铣刀只有两个刃口，而有些铣刀却有二十或更多的刃口。铣别可根据所用的铣刀形状分别加工平面或斜面、槽口、缝、齿轮齿及其它型面。23. In spite of that diversity of lathe-type machine tools, they all have common features with respect to construction and principle of operation.尽管车床的类型是多种多样的，但它们在结构和工作原理上都有共同的特征。24. The function of the gearbox is to provide a number of different spindle speeds (usually 6 up to 18 speeds). Some modern lathes have headstocks with infinitely variable spindle speeds, which employ frictional, electrical, or hydraulic drives.齿轮箱的作用是提供多种进给速度（通常是6到18级）。现在的车床的床头箱采作无级调速，由摩擦、电或者由液压驱动。25. It is actually an H-shaped block that slides on the lathe bed between the headstock and tailstock while being guided by the V-shaped guideways of the bed. The carriage can be moved either manually or mechanically by means of the apron and either the feed rod or the lead screw.它实际是一个H型块，通过床身上的V形导轨的导向，在床头箱和尾架之间的床身滑动。26. It involves pressing two hardened rolls with rough filelike surfaces against the rotating workpiece to cause plastic deformation of the workpiece metal.它通过用把两个象粗锉刀表面一样的硬的滚轮压在工件上引起工作金属的塑性变形。27. The cutting speed, which is usually given in surface feet per minute (SFM ), is the number of feet traveled in the circumferential direction by a given point on the surface (being cut )of the workpiece in 1 minute.切削速度，通常以英尺/分种表示，是在工件表面一个给定的点在圆周方向上一分钟内所走的英尺数。28. Jigs and fixtures are alike in that they both incorporate devices to ensure that the workpiece is correctly located and clamped, but they differ in that jigs incorporate means of tool guiding during the actual cutting operation, and fixtures do not.钻模和夹具是相似的，因为在它们都是为组合装置用来保证工件能够被正确的定位和夹紧，但是它们也有有所区别，钻模在实际加工过程中具有导向作用而夹具没有。29. Bolt holes often have 1.5mm or even 3.0mm clearance for the bolt, and the reader may doubt the necessity of making precision jigs for such work.螺栓孔与螺栓之间通常有1.5mm或者甚至有3mm的间隙，读者也许会产生疑问做这样的工作有必要制造精确的夹具吗。30. When work is located, as many of these freedom as possible must be eliminated, to ensure that the operation is performed with the required accuracy.当工件定位时，必须限制尽可能多的自由度以保证加工获得较高的精度。31. The workpiece must be supported beneath the point of clamping, to ensure that the forces are taken by the main frame of the jig or fixture, and on to the machine table and bed.工件必须被放在夹紧点下，保证切削力由钻模或夹具体来承受，结果作用在工作台或床身上。32. Jigs make it possible to drill, ream, and tap holes at much greater speeds and with greater accuracy than when the holes are produced by conventional hand methods.和用传统的手工加工方法相比，钻模能够以较大的加工速度和较高的精度进行钻孔、铰孔和攻丝。33. Cutting tools must also have high strength in order to be vibration and impact resistant，Strength in cutting tool material is not always proportional to hardnessSome of the hardest tool materials lack strength because they are too brittle切削刀具还必须具有高强度才能抗振动和抗冲击。切削刀具材料的强度并不都是与硬度成正比的。有些硬的刀具材料由于太脆而缺乏强度。34. Several of them have been developed largely because of the need to shape new high strength and temperature resistant alloys that are not easily worked by the older processes.其中的几种产生的原因主要是因为用来加工新出现的高强度和耐高温的合金，它们用传统的加工方法难易加工。35. The gap between the work and tool is filled with a suitable dielectric fluid, which is actually circulated under pressure, or a sufficient reservoir surrounding a workpiece is maintained, This is necessary, otherwise the dielectric will soon foul, with the metal debris coming off the workpiece.工件和刀具之间的间隙充满着一种适合的电解液，它们在一定的压力下做循环流动，或者在工件周围形成一个充足的储存区，这一点是十分必要的，否则由于工件上金属切削的脱落电解液就会变脏。36. The recent increase in the use of hard, high-strength, and temperature-resistant materials in engineering has necessitated the development of new machining techniques.近来，越来越多的硬、高强度工程材料的使用使得发展的新的加工工艺成为必要。37. The elimination of the mechanical stage also overcomes one difficulty inherent in conventional machining, namely, the increase in tool forces and tool wear encountered when machining the harder metals and alloys used in modern engineering practice.这种加工方法克服了传统加工方法存在的一个问题，也就是在现代工程实践中，当加工硬材料或合金时切削力和刀具磨损会增加很多。38. The current flows between the wheel, which is connected to the positive terminal, and the workpiece, which is connected to the negative terminal of a DC supply.电流在砂轮之间流动，它们连接到直流电源的正极，而工件连接到负