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第二章：内燃机（INTERNAL COMBUSTION ENGINE）1)Energy and power:Engines used in automobiles are internal combustion heat engines. They convert the chemical energy of the gasoline into heat within a power chamber that is called a combustion chamber. Heat energy released in the combustion chamber raises the temperature of the combustion gases within the chamber. The increase in gas temperature causes the pressure of the gases to increase. The pressure developed within the combustion chamber is applied to the head of a piston to produce a usable mechanical force, which is then converted into useful mechanical power.能源是用于生产电力。
化工能源是转化为燃料的燃烧的热量，这个过程被称为燃烧。
如果发动机燃烧发生在气缸内的地方，被称为发动机内部燃烧发动机。
如果燃烧发生在气缸外的地方，被称为发动机外部燃烧发动机。
用于汽车的能源叫内部燃烧高能源，高温能源在燃烧室里降低能缓解气体燃烧在气缸内的温度。
燃烧气体温度的升高引起气压变大，燃烧室内发展应用到了活塞产生一个可用的机械力，然后将其转换成有用的机械能。
2)Engine terms:Linking the piston by a connecting rod to a crankshaft causes the gas to rotate the shaft through half a turn. The power stroke "uses up" the gas, so means must be provided to expel the burnt gas and recharge the cylinder with a fresh petrol-air mixture: this control ofgas movement is the duty of the valves;活塞通过连杆和曲轴连接，使得气体带动曲轴旋转半圈。
（完整版）船舶专业英语（课文+翻译）Chapter 1 Ship Design（船舶设计）Lesson 2 Ships Categorized（船舶分类）2.1 Introduction（介绍）The forms a ship can take are innumerable. 一艘船能采用的外形是不可胜数的A vessel might appear to be a sleek seagoing hotel carrying passengers along to some exotic destination; a floating fortress bristling with missile launchers; 。
or an elongated box transporting tanks of crude oil and topped with complex pipe connections. 一艘船可以看做是将乘客一直运送到外国目的地的优美的远航宾馆。
竖立有导弹发射架的水面堡垒及甲板上铺盖有复杂管系的加长罐装原油运输轮None of these descriptions of external appearance, however, does justice to the ship system as a whole and integrated unit所有这些外部特点的描述都不能说明船舶系统是一个总的集合体self-sufficient,seaworthy, and adequately stable in its function as a secure habitat for crew and cargo. ——船员和货物的安全性功能：自给自足，适航，足够稳定。
This is the concept that the naval architect keeps in mind when designing the ship and that provides the basis for subsequent discussions, not only in this chapter but throughout the entire book.这是一个造船工程师设计船舶使必须记住的、能为以后讨论提供根据的观念，不仅涉及本章也贯穿全书。
专业英语短文翻译2南京邮电大学复习资料五:《专业英语》短文翻译1.The reader may ask , how does the demultiplexer know which groupof 8-digits relates to channel 1, 2, and so on ? Clearly this is important ! The problem is easily overcome by specifying a frame format , where at the start of each frame a unique sequence of pulses called the frame code , or synchronization word , is placed so as to identify the start of the frame. A circuit of the demultiplexer is arranged to detect the synchronization word, and thereby it knows that the next group of 8-digits corresponds to channel 1.2.Advances in audio, video and speech coding and compression algorithms and progress in Very Large System Integration technology influence the bit rate generated by a certain service and thus changethe service requirements for the network. In the future, new services with unknown requirement will appear. For the time being it is yet unclear, e. g. what the requirement in terms of bit rate for HDTV will be. A specialized network has great difficulties in adapting to changing or new service requirements.3.When the transmitter wishes to send data, it first places the line in a space level (i. e. , the complement of a mark) for one element period. This element is called the start bit and has a duration of T seconds. The transmitter then sends the character, 1 bit at a time, byplacing each successive bit on the line for a duration of T seconds, until all bits have been transmitted. Then a single parity bit is calculated by the transmitter and sent after the data bits. Finally, the transmitter sends a stop bit at a mark level (i. e. the same level as the idle state) for one or two bit periods. Now the transmitter may send another character whenever it wishes4.The cellular switch, which can be either analog or digital, switches calls to connect mobile subscribers to other mobile subscribers and to the nationwide telephone network.. It also contains data links providing supervision links between the processor and the switch and between the cell sites and the processor. The radio link carries the voice and signaling between the mobile unit and the cell site. Microwave radio links or wire lines carry both voice and data between the cellsite and the MTSO.5.Today's telecommunication networks are characterized by specialization . This means that for every individual telecommunication service at least one network exists that transports this service. A few examples of existing public networks are described below Computer data are transported in the public domain by a packet switched data network (PSDN) based on X.25 protocol6.Today’s telecommunication networks are characterized by specialization . This means that for every individual telecommunication service at least one network exists that transports this service. A few examples of existing public networks are described below:Computer data are transported in the public domain by a packet switched data network (PSDN) based on X.25 protocols.Television signals can be transported in three ways: broadcast via radio waves using ground antenna, by the coaxial tree network of the community antenna TV (CATV) network or recently via a satellite, using the so-called direct broadcast system (DBS)7.By far the most popular serial interface between a computer andits CRT (显示器) terminal isthe asynchronous serial interface . This interface is so called because the transmitted data and the received data are not synchronized over any extended period and therefore no special means of synchronizing the clocks at the transmitter and receiver is necessary. In fact, the asynchronous serial data link is a very old form of data transmission system and has its origin in the era of the第1页共4页南京邮电大学teleprinter.8.At the receiving end of an asynchronous serial data link, the receiver continually monitors the line looking for a start bit. Once the start bit has been detected, the receiver waits until the end of thestart bit and then samples the next N bits at their centers, using a clock generated locally by the receiver. As each incoming bit is sampled, it is used to construct a new character. When the received character has been assembled, its parity is calculated and compared with the receivedparity bit following the character. If they are not equal, a parityerror flag is set to indicate a transmission error.9.If we consider binary transmission , the complete informationabout a particular message will always be obtained by simply detecting the presence or absence of the pulse. By comparison, most other forms of transmission systems convey the message information using the shape , or level of the transmitted signal ; parameters are most easily affected by the noise and attenuation introduced by the transmission path . Consequently there is an inherent advantage for overcoming noisy environments by choosing digital transmission.10. The Internet is the largest repository of information which can provide very large network resources . The network resources can be divided into network facilities resources and network information resources . The network facilities resources provide us the ability of remote computation and communication . The network information resources provide us all kinds of information services , such as science , education , business , history , law , art , and , entertainment , etc11.The SDH standards are based on the principle of direct synchronous multiplexing which is the key to cost effective and flexible telecommunication networking. In essence, it means that individual tributary signals may be multiplexing directly into a higher rate SDH signal without intermediate stage of multiplexing. SDH Network Elements can then be interconnected directly with obvious cost and equipment savings over the existing network.12.Improvements in component performance, cost, and reliability by 1980 led to major commitments on the part of telephone companies. Fibre soon became the preferred transmission medium for long-haul trunks. Some early installations 0. 8 µm light sources and graded-index multimode fibre, but by 1983, designers of intercity links were thinking in terms of 1. 3 µm, single-mode systems. The single-mode fibere, used in conjunction with a 1. 3 µm laser, provides a bandwidth advantage which translates into increased repeater spacings for high data rate system.13.The individual elements of multimedia are already handled by a standard 486 personal computer, such things as audio, graphics and text, but the major challenge is in real time video, for this is the major business requirement and a necessity if multimedia systems are to become standard items for the desktop. This real time processing requires a vast amount of data storage and this is a function of the amount of information contained in a colour picture, for instance a normal640×480pixel colour picture requires well over 1 M bytes of storage to give the required quality, though for full motion video this is increased up to 100 M bytes of data.1.读者也许会问，解复用器怎么知道哪一组8位码对应于第一路、第二路及其他各路呢?显然这是很重要的。
2－A Why study geometry Many leading institutions of higher learning have recognized that positive benefits can be gained by all who study this branch of mathematics. This is evident from the fact that they require study of geometry as a prerequisite to matriculation in those schools. 许多居于领导地位的学术机构承认，所有学习这个数学分支的人都将得到确实的受益，许多学校把几何的学习作为入学考试的先决条件，从这一点上可以证明。
Geometry had its origin long ago in the measurement by the Babylonians and Egyptians of their lands inundated by the floods of the Nile River. The greek word geometry is derived from geo, meaning “earth” and metron, meaning “measure” . As early as 2000 . we find the land surveyors of these people re-establishing vanishing landmarks and boundaries by utilizing the truths of geometry . 几何学起源于很久以前巴比伦人和埃及人测量他们被尼罗河洪水淹没的土地，希腊语几何来源于geo ，意思是”土地“，和metron 意思是”测量“。
A. Classification of cells and organisms细胞和有机体的分类Cells are the basic units of living organism, with the exception of viruses whose structure and function are different from cells. Although a nerve cell looks entirely different from a red blood cell, their organizations are essentially the same. Even plant cells and animal cells share significant similarity in the overall organization. 除病毒外，细胞是生物体结构和功能的基本单位，虽然，一个神经细胞和一个血红细胞看起来完全不同，但它们的组织结构本质上是相同的，甚至植物细胞和动物细胞在整个组织、结构上具有相似性。
All cells are divided into two types: prokaryotic cells and eukaryotic cells. The prokaryotic cell does not have a nucleus. The eukaryotic cell contains a nucleus.所有细胞可分为两种类型;原核细胞和真核细胞。
原核细胞不具有细胞核，真核细胞具有细胞核。
Eukaryotes are the organisms made up of eukaryotic cells. They include protista, fungi, animals and plants. Prokaryotes include archaebacteria and eubacteria. They are single-cell organisms.真核生物是由真核细胞组成的有机体，他们包括原生生物真菌、动物和植物，原核生物包括古细菌和真细菌，他们是单细胞有机体。
专业英语八级-翻译(二)(总分：60.00，做题时间：90分钟)一、{{B}}Exercise One{{/B}}(总题数：1，分数：10.00)1.哲学家们以各种各样的方式解释世界。
哲学是言而不是行。
哲学家断乎改变不了自然与社会。
是不能也，非不为也。
哲学不是科学技术，不是生产力。
哲学是怀疑，是思虑，是静观，是探索。
严格来说，哲学不是解释宇宙，那是自然科学的事。
哲学家至多只能解释人生，解释自己，解释文本。
哲学也不是知识，不是知识体系，不是儿何学，物理学那样一大套公理、公式，可以解决实际生存问题。
哲学的精神永远是探究、怀疑、发问、深思；而不是提供现存答案。
哲学家有些不食人间烟火，他远离田野车间，甚至也不拿天文望远镜观察天体，而只是坐存静湍的书斋罩读书、思考、思考那究竟至极、虚无缫渺的本体问题。
哲学家孤苦伶仃，独处一室之中。
面对古往今来的大哲学家遗留下来的问题，他苦苦沉思。
他唯一的财富是文本，哲学因而就是解释文本，而不是解释宇宙。
哲学家只是一味地同古往今来的灵魂交谈——他读书，是同古昔人物交谈：他写作，是同子孙后代奁谈；他讲演，是同莘莘学子交谈；他沉思是同自己交谈。
他长于洞见，洞见未来；他善于遐想，遐想无限；他耽于梦幻，幻游彼岸；他富于关怀，关怀永恒。
他同远在天涯的哲人和精神交谈，在这个意义上，他视通万里，思接千载。
他伟大，他不朽，他同古往今来的灵魂对话。
以哲学为命运的人应当准备在崎岖小路上独行，没有目的，也不会有黄金滚滚而来。
告别鲜花、头衔、掌声和奖品，钟情于思，就会有真哲学。
（分数：10.00）__________________________________________________________________________________________ 正确答案：()解析：To some extent, philosophers tend to refrain from any secular involvements. A philosopher seldom frequents farmlands or factories, and he even never bothers to look through a telescope to make any observation of celestial bodies. He is only fond of staying in his personal library, in all its quietude, where he indulges himself in book reading and in musing, pondering on those intangible onto logical issues that he deems to be of ultimate significance. A philosopher is willing to surrender himself to utter loneliness and seclusion, confining himself to a room of his own, in a state of overwhelming solitude. In the face of the philosophical issues left over by great philosophical thinkers, ancient and modem, he contemplates painstakingly. The only wealth to his possession is texts. Therefore, the task of philosophy is to interpret texts rather than to interpret the universe. A philosopher is solely concerned with conducting dialogues with the great souls from ancient antiquity to the contemporary era. In reading books, he converses with the ancients. In writing his own books, he converses with the progeny. In delivering lectures, he converses with a multitude of young students. In contemplating, he converses with himself.二、{{B}}SECTION B English TO Chinese{{/B}}(总题数：1，分数：10.00)2.The effect of any writing on the public mind is mathematically measurable by its depth of thought.{{U}} How much water does it draw? If it awaken you to think, if it lift you from your feet with the great voice of eloquence. then the effect is to be wide. slow. permanent, over the minds of men; if the pages instruct you not. they will die like flies in the hour. The way to speak and write what shall not go out of fashion is. to speak and write sincerely. The argument which has not power to reach my own practice, I may well doubt, will fail to reach yours. But take Sidney's maxim: --"Look in thy heart, and write." He that writes to himself writes to an eternal public. That statement only is fit to be made public, which you have come at in attempting to satisfy your own curiosity. The writer who takes his subject from his ear, and not from his heart, should know that he has lost as much as he seems to have gained, and when the empty book has gathered all its praise, and half the people say, "What poetry! What genius!" it still needs fuel to make fire. {{/U}}That only profits which is profitable, Life alone can impart life; andthough we should burst, we can only be valued as we make ourselves valuable.（分数：10.00）__________________________________________________________________________________________ 正确答案：()解析：那么计算标准是什么呢?如果一部作品发人深省，如果它以其伟大雄辩的声音令你有醍醐灌顶之感，那么该作品对人类思想的影响便是宽广、渐进、永恒的。
专业英语翻译西张村桥Bridge as a transportation hinge in ensuring smooth flow of traffic plays a vital role，but the bridge structure might sueffer from many kinds of diseases during the service life which threaten the safety of the bridge . In this thesis, relying on the Xi Zhang Cun Bridge , established by the use of grillage finite element model, Calculated the structural performance influence of Overloading, temperature, wind, and bearings failure; Finally, given some suggestion for Safety management and maintenance of the Xi Zhang Cun bridge.1.Overloading mainly influence the upper structure of bridge. In the overload situation ,the internal force increase 50%~90%;the cross section of mid-span subjected to tensile stress ,the stress value will surpass Concrete tensile strength and Cause section cracking in Eccentric loading .Overloading lead to Counteracting force increases, what will accelerate the bearing damage. Overloading effect on the bridge related to the vehicle type ,The more concentrated vehicle axle weight, the greater the impact .To ensure the safety of the bridge, the Bridge managers should strengthen the management of passing vehicle, Prohibit the overload vehicles passing the bridge. For some heavy vehicles ,Overloading detection should be done earnestly before it passing the bridge .Simultaneously should avoid the heavy vehicles keeping to the side to go crowdedly, prevents the bridge partial stress oversized.2.The wind load is primary factor which causes the bridge lateral deformation, the maximal displacement of the pier top is 57.51mm under wind load. Because of the lateral deformation of the bearings, the girder and the bent cap have displacement difference ,the Maximum value is 98.38mm,this might lead to the girder run in to the anti-knock block. The maximal lateral deformation of piers is 7.28 mm under temperature gradient load, The maximum stress at the side toward the sunis-4.34MPa. When the wind blows to the bridge pier back positive side, The bridge pier stress is most disadvantageous, The stress at the back positive side may reach to -10.45MPa and the side toward the sun appears the tensile stress.Therefore,we should strengthen the bridge examination and maintenance, we Should pay attention to the bearings especially whether has the lateral shear distortion, the girder and the bent cap whether has the contact, Whether the bridge pier does appear the crack.3. Bearing failure mainly affect bridge local stress. At the same pivot, when a bearing hanging in the air, the counteracting force of adjacent bearings increase and other Counteracting force reduce. while peripheral bearings hanging in the air is most disadvantageous, compared to the original bridge, counteracting force can be increased to 2.7 times. bearing hanging in the air caused the shear and bending moment of the girder increasing, the maximum shear can increased to 2.76 times and the maximum bending moment can increase 20% when the side of bearing failed, the maximum shear can increased to 1.75 times and the maximum bending moment can increase 6% when the middle of bearing failed. The ratio of the largest shear after andbefore bearings hanging in the air is between 6.919 ~ 19.266 and the ratio of maximum positive and negative bending moment were 18.9 times and 70.76 times.桥梁作为交通枢纽在确保交通顺畅起着至关重要的作用,但桥梁结构可能在服役期遭受到各种各样的对其安全造成威胁的病害。
Chapter 2 Boiler第二章锅炉Air heater 空预器Commissioning 试运行Anchor 支座，固定Compressor 压缩机、压气机Anhydrous ammonia 无水氨Condenser 凝汽器Anthracite 无烟煤Containment 反应堆安全壳Atomized 雾化Convection 对流Austenitic 奥氏体钢Coolant 制冷剂Auxialiary 辅助机械Coordinated 坐标，定位Axis 轴Corten低合金耐腐蚀钢Bagasse 甘蔗渣Counterflow 逆流（换热器）Bare tube 光管Creep strength 蠕变强度Bark 树皮Criterion 标准Beam 梁，横梁Critical pressure 临界压力Bituminous coal 烟煤Culm 煤屑Blade 叶片Cyclone furnace 旋风炉Blast 鼓风Debris 残骸、有机残留物Blowdown 排污Decane 癸烷Boiler 锅炉Decay 分解Bulk 大块的Deposited 沉积，沉淀的Burner zone 燃烧器区域Deterioration 恶化Butane 丁烷Diesel oil 柴油Calcination 煅烧Differential 差动，微分Capacity 出力Distillate 馏出物Carbon steel 碳钢Distortion 变形Cerium 铈Division wall 分隔墙，双面水冷壁Chromium 铬Drainage 疏水Drum 汽包Circulating fluidized bed CFB 循环流化床锅炉Coal char 煤焦Dwell time 保留时间Cogenerator 热点联产机组Economizer 省煤器Combustion 燃烧Embrittlement 脆性，脆化Equalization 均衡，平衡Ingress进口，入口Erosive 侵蚀的，腐蚀的In-line 顺列Ethane 乙烷Inorganic 无机的Evaluate 评估，评价Ion 离子Evaporate 蒸发Jurisdiction 权限Excess air 过量空气Lignite 褐煤Extended surface 扩展受热面Lime 石灰Fatigue 疲劳Limestone 石灰石Feedwater 给谁Low alloy 低合金钢Ferrite 铁素体Low-volatile 低挥发分的Fin 鳍片，肋片Margin 裕量，安全系数Flange 法兰Matrix 矩阵Flue gas 烟气Membrane 膜Fouling 沾污Methane 甲烷Furnace 炉膛Mill 磨煤机Generator 发电机Molecule 分子Geological 地质的Molten 熔化Girth 环形Nitric oxide 氮氧化物Govern 控制、调节Nonpressure 非承压的Gravity 重力Nontoxic 无毒的Header 联箱，集箱Organisms 有机体Helical 螺旋状的Oxidation 氧化Helium 氦Peat 泥煤Heterogeneous 不均匀的Pendants superheat platen悬吊式屏式过热器Hopper 斗，料斗Pentane 戊烷Husk 壳，外壳Petrochemical 石油化工制品Hydraulic 水力的，液压的Petroleum 石油制品Ignite 点火Plasma spray coating 等离子喷涂Impurity 杂质Platen 屏Inert 惰性Polymer 聚合物Inferior 低级的，劣质的Pores 气孔，小孔Ingredients 成分Porosity多空的Potassium 钾Slurry 水煤浆Prandtl numbers 普朗特数Sodium 钠Prefabricated 预制的Solvents 溶剂Premium fuel 优质燃料Sootblower 吹灰器Pressure loss 压力损失Sour gas 含硫气体Primary air 一次风Specification 规格Propane 丙烷Stable ignition 稳定着火Proximate analysis 工业分析Stanton number 斯坦顿数Pulp 纸浆Saturated 饱和的Pyrites 黄铁矿Straw 稻草Radius 半径，范围Steam line blowing 蒸汽管路吹灰Rare earth element 稀土元素Steams 茎，杆Recuperator 间壁式换热器Stress corrosion 应力腐蚀Regenerator 回热器，蓄热器Structural formula 结构式Regulate 控制，调节Stud 双头螺栓Repercussions 反应Subbituminous 贫煤，次烟煤Reservoirs 储气罐Suction 真空，负压Residuale fuel oil 渣油Sulphur 硫Resonant 共振Superheater 过热器Retract缩回Swamp 沼泽Reynolds number 雷诺数Sweet gas 无硫气Rigid 刚性的，紧密地Switchgear 配电装置，开关装置Rollers 辊子Temperature-entropy 温熵图Scale 水垢，Tenacious 黏的Seal 密封Thermodynamics 热力学Sedimentary 沉积Tube bundles 管束Serpentine tube 蛇形管Tubular 管状的Shale 页岩Turbine 汽轮机Silica 二氧化硅Velocity 速度Silt 淤泥Vertical spidle mill 中速磨，立轴磨Single-phase 单相Vessel 容器Skin casing 外护板Viscosity 黏度Slag 结渣V olumetric expansion 体膨胀Vulnerable 易损的，薄弱的DEH 数字电液系统Wear磨损DNB 偏离核态沸腾Welded 焊接FDF 送风机Wingwall屏式凝渣管FGD 烟气脱硫Yttrim 釔FSSS 炉膛安全检测保护系统Abbreviations HRB 回热锅炉AFBC 常压流化床燃烧IDF 引风机AFCO 燃料自动切断IGCC 整体煤气化联合循环AFWC 给水自动切断LMTD 对数平均温差ASME 美国机械工程师协会MFT 主燃料切断ATM 标准大气压MUF 锅炉补给水BFP 锅炉给水泵NWL 正常水位BUT 按钮OFA 火上风，燃尽风BWC锅炉水浓度PFBC 增压流化床燃烧BYP 旁路SSC 刮板除渣机CFBB 循环流化床锅炉TGA 热重分析仪MCR 最大连续蒸发量UBC 未燃烧DAS 数据采集系统WFGD 湿法烟气脱硫2.1 IntroductionBoilers use heat to convert water into steam for a variety of applications. Primary among these are electric power generation and industrial process heating. Steam has become a key resource because of its wide availability, advantageous properties and non toxic nature. The steam flow rates and operating conditions can vary dramatically; from 1000lb/h (0.1kg/s) in one process use to more than 10 million lb/h (1260kg/s) in large electric power plant; from about 14.7 psi (1 bar) and 212ºF in some heating applications to more than 4500 psi (310bar) and 1100ºF (593℃) in advanced cycle power plant.2.1 简介SSC锅炉利用热量使水转变成蒸汽以进行各种利用。
专业英语翻译1.1、1.2、（2.1-2.4）、3.1、3.2、（3.4-3.7）、4.1、4.2P1~51.1汽车构造汽车发动机基本原理汽车包括五个基本组成部分，它们是：1.发动机：是汽车的动力源，包括燃油系统、润滑系统、冷却系统和电器部分。
2.车架：是支撑发动机、车轮、转向和制动系统以及车身。
3.动力传动系：它将动力由发动机（经离合器、变速箱、驱动轴、差速器和后轴）传至车轮。
4.车身5.车身附件；包括散热器、照明设备、风挡、刮雨器等等。
发动机是使汽车移动的动力源。
因为汽油是在发动机气缸或燃烧室内部燃烧，这种发动机通常称为内燃机。
这是相对于燃料在发动机外部燃烧的外燃机来说的（如蒸汽机）。
在发动机气缸内的燃烧产生动力。
由动力传动系统将动力由发动机传至车轮，车轮转动使用车辆行驶。
燃油系统在动力产生过程中起举足轻重的作用。
因为它向发动气缸中供给燃油。
在发动机的每个气缸中．汽油蒸汽和空气的混合汽体进入气缸，活塞上行在气缸内压缩混合气，然后电火花点燃压缩的混合气推动活塞下行。
当然，活塞不会被推出气缸外部，活塞在气缸内做简单的上下往复运动—活塞上行压缩混合气，当混合气燃烧时，活塞下行。
在动力驱动车轮转动之前，活塞的直线运动必须变为旋转运动。
这种转变由曲轴上的曲柄和连杆来实现。
发动机的气门使燃烧废气排到气缸外部、将新鲜的汽油蒸汽和空气带到气缸内部。
在气缸封闭端有两个开口，每个开口与一个气门相通。
气门是带长杆的精密加工阀体。
当气门关闭或落座时（也就是气门上行至开口处）开口被密封，这时气体不能通过气门泄漏。
当气门开启时，气体便可从开口流出。
2、气门被发动机凸轮轴上的凸轮驱动打开。
凸轮有一个最高点（或凸角），每当凸轮转动时，凸角转至气门挺柱下部并使挺柱向上运动。
挺柱通过推杆将向上的运动传气门摇臂绕其支撑点旋转向下推动气门杆，使气门下移打开。
当凸轮转动使凸角转离挺柱下端时，刚度较大的气门弹簧将气门推回原位落座。
气门弹簧靠弹簧座和锁销与气门杆上端相联接。
Biologists and chemists divide compounds into two principal classes, inorganic and organic. Inorganic compounds are defined as molecules, usually small, that typically lack carbon and in which ionic bonds may play an important role. Inorganic compounds include water, oxygen, carbon dioxide, and many salts, acids, and bases.生物学家和化学家分裂成两个主要种类化合物、无机和有机。
无机化合物被定义为分子,通常小,通常缺乏的碳离子束缚,那么它就能起到重要的作用。
无机化合物包括水、氧气、二氧化碳和许多盐、酸、和根据地。
化碳和许多盐、酸、和根据地。
All living organisms require a wide variety of inorganic compounds for growth, repair, maintenance, and reproduction. Water is one of the most important, as well as one of the rmost abundant, of these compounds, and it is particularly vital to microorganisms. Outside the cell, nutrients are dissolved in water, which facilitates their passage through cell membranes. And inside the cell , water is the medium for most chemical reactions. In fact, water is by far the most abundant component of almost all living cells. Water makes up 5% to 95% or more of each cell, the average being between 65% and 75%. Simply stated, no organism can survive without water 所有生物体需要多种无机化合物的增长、维修、维护、和繁衍。
学术英语（社科）Unit2二单元原文及翻译UNIT 2 Economist1.Every field of study has its own language and its own way of thinking. Mathematicians talk about axioms, integrals, and vector spaces. Psychologists talk about ego, id, and cognitive dissonance. Lawyers talk about venue, torts, and promissory estoppel.每个研究领域都有它自己的语言和思考方式。
数学家谈论定理、积分以及向量空间。
心理学家谈论自我、本能、以及认知的不一致性。
律师谈论犯罪地点、侵权行为以及约定的禁止翻供。
2.Economics is no different. Supply, demand, elasticity, comparative advantage, consumer surplus, deadweight loss—these terms are part of the economist’s language. In the coming chapters, you will encounter many new terms and some familiar words that economists use in specialized ways. At first, this new language may seem needlessly arcane. But, as you will see, its value lies in its ability to provide you a new and useful way of thinking about the world in which you live.经济学家也一样。
第二单元力学概论力学的基本概念：力学是用来处理运动，时间和力的科学分析的分支，它由静力学和动力学组成。
静力学研究静态系统的分析，这时，时间不是一个考虑的因素;动力学则是随时间变化的系统。
力是通过相配合的表面传递到机器各个构件的。
例如，从齿轮到轴或一个齿轮通过啮合齿传动到另一个齿轮或连杆通过轴承传到杠杆，从V带到滚轮或从凸轮到传动件。
有许多理由都必须知道力的大小。
力在边界及配合表面的分布必须要合理，其强度必须在构成表面的材料的工作极限内。
例如，如果作用在套筒轴承上的力太大，将会把油膜挤出，并导致金属表面的胶合，过热和轴承过快失效，动力学的研究主要是确定李的大小、时间和位置。
下面将说明一下我们这方面的研究力：我们最早的关于力的想法是源于我们对推、举和拉河中物体的需要。
因此力是一个物体对另一个物体的作用。
自觉对力的联系包括力作用的位置，方向和大小，这些称为力的特性。
物质：物质是一种材料或实物，如果它完全封闭则称为物体。
质量：牛顿吧质量定义为物体的数量，由体积和密度来衡量。
这定义并不是很多人满意的，因为密度是单位体积的质量。
通过猜想我们可以谅解牛顿，可能他并不认为那是个定义。
然而，他已经认识到了一个事实，那就是所有的物体都具有不同于重量的内在性质。
所以，尽管月球重量不同于地球重量，但一块月球上的岩石仍有特定不变的本质数量。
这个恒定的本质数量或物质食粮就是岩石的质量。
国际单位制最大的有点事它对任何物体有且仅有一个单位。
长度的单位为米，质量的单位为千克，力的单位为牛顿，时间的单位为秒等等。
为了和这种特性保持一致，就要求一个给定的单位或词不能仅一个被认可的技术名称在二个物理量中使用。
然而，习惯叫做“重量”的这个词已经在技术和非技术领域广泛使用，表示着物体所受的引力和其本身质量。
粒子：粒子就是指尺寸小到可以忽略的物体。
刚体：物体要么是弹性的，要么是塑性的，只要作用上力都会产生变形。
当物体形变量很小时，通常将其假想为刚体，即没有变形的能力，作此假想以便简化分析。
专业英语八级翻译-汉译英(二)(总分：100.00，做题时间：90分钟)一、{{B}}TRANSLATION{{/B}}(总题数：0，分数：0.00)二、{{B}}CHINESE TO ENGLISH{{/B}}(总题数：5，分数：100.00)1.华裔电脑名人王安博士说，影响他一生的事发生在他6岁之时。
{{U}}一天他外出玩耍，经过一棵大树时，突然有一个鸟巢掉在他的头上，里面滚出一只嗷嗷待哺的小麻雀。
他决定把它带回去喂养，连同鸟巢一起带回了家，走到家门口，突然相起妈妈不允许他在家里养小动物。
他轻轻地把小麻雀放在门后，急忙走进屋去请求妈妈，在他的哀求下妈妈破例答应了儿子。
王安兴奋地跑到门后，不料小麻雀已经不见了，一只黑猫在意犹未尽地擦拭着嘴巴。
王安为此伤心了很久。
从此，他记取了一个很大的教训，只要是自己认定的事情，决不可优柔寡断。
犹豫不决固然可以免去一些做错事的机会，但也失去了成功的机遇{{/U}}。
（分数：20.00）__________________________________________________________________________________________正确答案：(Dr. An Wang, a well-known Chinese American computer entrepreneur, once remarked that an incident that had a lifetime influence on him occurred when he was six. {{U}}One day, he ran outside to play. As he walked past a large tree from underneath, a bird nest fell on his head and out fluttered a baby sparrow crying piteously for food. He decided to keep the poor creature at home and took it along with its nest. He was about to enter the house when he remembered that his mother would not allow him to keep any pets. Gently, he placed the little sparrow behind the door and hurried in to seek approval from his mother, who finally bent the rule upon her son's pleas. Overjoyed, he ran back to the door, only to find the bird disappeared and a black cat rubbing its mouth with its paws after a delicious meal. This incident had saddened Wang for a long time. An important lesson he learned from it was: never hesitate over what one believes to be the right thing to do; indecision may allow one to avoid certain mistakes, but it may also deprive one of the opportunity to succeed{{/U}}.)解析：[解析] 电脑名人：根据语境将其具体化为“well-known computer entrepreneur”。
1 1－A What is mathematics Mathematics comes from man’s social practice, for example, industrial and agricultural production, commercial activities, military operations and scientific and technological researches. And in turn, mathematics serves the practice and plays a great role in all fields. No modern scientific and technological branches could be regularly developed without the application of mathematics.数学来源于人类的社会实践，比如工农业生产，商业活动， 军事行动和科学技术研究。反过来，数学服务于实践，并在各个领域中起着非常重要的作用。 没有应用数学，任何一个现在的科技的分支都不能正常发展。From the early need of man came the concepts of numbers and forms. Then, geometry developed out of problems of measuring land , and trigonometry came from problems of surveying . To deal with some more complex practical problems, man established and then solved equation with unknown numbers ,thus algebra occurred. Before 17th century, man confined himself to the elementary mathematics, i.e. , geometry, trigonometry and algebra, in which only the constants are considered.很早的时候，人类的需要产生了数和形式的概念，接着，测量土地的需要形成了几何，出于测量的需要产生了三角几何，为了处理更复杂的实际问题，人类建立和解决了带未知参数的方程，从而产生了代数学，17世纪前，人类局限于只考虑常数的初等数学，即几何，三角几何和代数。The rapid development of industry in 17th century promoted the progress of economics and technology and required dealing with variable quantities. The leap from constants to variable quantities brought about two new branches of mathematics----analytic geometry and calculus, which belong to the higher mathematics. Now there are many branches in higher mathematics, among which are mathematical analysis, higher algebra, differential equations, function theory and so on.17世纪工业的快速发展推动了经济技术的进步， 从而遇到需要处理变量的问题，从常数带变量的跳跃产生了两个新的数学分支-----解析几何和微积分，他们都属于高等数学，现在高等数学里面有很多分支，其中有数学分析，高等代数，微分方程，函数论等。Mathematicians study conceptions and propositions, Axioms, postulates, definitions and theorems are all propositions. Notations are a special and powerful tool of mathematics and are used to express conceptions and propositions very often. Formulas ,figures and charts are full of different symbols. Some of the best known symbols of mathematics are the Arabic numerals 1,2,3,4,5,6,7,8,9,0 and the signs of addition, subtraction , multiplication, division and equality.数学家研究的是概念和命题，公理，公设，定义和定理都是命题。符号是数学中一个特殊而有用的工具，常用于表达概念和命题。公式，图表都是不同的符号……..The conclusions in mathematics are obtained mainly by logical deductions and computation. For a long period of the history of mathematics, the centric place of mathematics methods was occupied by the logical deductions. Now , since electronic computers are developed promptly and used widely, the role of computation becomes more and more important. In our times, computation is not only used to deal with a lot of information and data, but also to carry out some work that merely could be done earlier by logical deductions, for example, the proof of most of geometrical 2
theorems.数学结论主要由逻辑推理和计算得到，在数学发展历史的很长时间内，逻辑推理一直占据着数学方法的中心地位，现在，由于电子计算机的迅速发展和广泛使用，计算机的地位越来越重要，现在计算机不仅用于处理大量的信息和数据，还可以完成一些之前只能由逻辑推理来做的工作，例如，大多数几何定理的证明。
1－B Equation1 An equation is a statement of the equality between two equal numbers or number symbols. Equation are of two kinds---- identities and equations of condition.An arithmetic or an algebraic identity is an equation. In such an equation either the two members are alike. Or become alike on the performance of the indicated operation.等式是关于两个数或者数的符号相等的一种描述。等式有两种－恒等式和条件等式。算术或者代数恒等式是等式。这种等式的两端要么一样，要么经过执行指定的运算后变成一样。An identity involving letters is true for any set of numerical values of the letters in it.An equation which is true only for certain values of a letter in it, or for certain sets of related values of two or more of its letters, is an equation of condition, or simply an equation. Thus 3x-5=7 is true for x=4 only; and 2x-y=0 is true for x=6 and y=2 and for many other pairs of values for x and y.含有字母的恒等式对其中字母的任一组数值都成立。一个等式若仅仅对其中一个字母的某些值成立，或对其中两个或着多个字母的若干组相关的值成立，则它是一个条件等式，简称方程。因此3x-5=7仅当x=4 时成立，而2x-y=0，当x=6,y=2时成立，且对x, y的其他许多对值也成立。A root of an equation is any number or number symbol which satisfies the equation.There are various kinds of equation. They are linear equation, quadratic equation, etc.方程的根是满足方程的任意数或者数的符号。方程有很多种，例如： 线性方程，二次方程等。To solve an equation means to find the value of the unknown term. To do this , we must, of course, change the terms about until the unknown term stands alone on one side of the equation, thus making it equal to something on the other side. We then obtain the value of the unknown and the answer to the question. To solve the equation, therefore, means to move and change the terms about without making the equation untrue, until only the unknown quantity is left on one side ,no matter which side.解方程意味着求未知项的值，为了求未知项的值，当然必须移项，直到未知项单独在方程的一边，令其等于方程的另一边，从而求得未知项的值，解决了问题。因此解方程意味着进行一系列的移项和同解变形，直到未知量被单独留在方程的一边，无论那一边。Equation are of very great use. We can use equation in many mathematical problems. We may notice that almost every problem gives us one or more statements that something is equal to something, this gives us equations, with which we may work if we need it.方程作用很大，可以用方程解决很多数学问题。注意到几乎每一个问题都给出一个或多个关于一个事情与另一个事情相等的陈述，这就给出了方程，利用该方程，如果我们需要的话，可以解方程。 2－A Why study geometry? Many leading institutions of higher learning have recognized that positive benefits can be gained by all who study this branch of mathematics. This is
