To one degree or another, most materials experience some type of interaction with a large number of diverse environments. Often, such interactions impair a material’s usefulness as a result of the deterioration of its mechanical properties (e.g., ductility and strength), other physical properties, or appearance. Occasionally, to the chagrin of a design engineer, the degradation behavior of a material for some application is ignored, with adverse consequences.
Deteriorative mechanisms are different for the three material types. In metals, there is actual material loss either by dissolution (corrosion) or by the formation of nonmetallic scale or film (oxidation). Ceramic materials are relatively resistant to deterioration, which usually occurs at elevated temperatures or in rather extreme environments; the process is frequently also called corrosion. For polymers, mechanisms and consequences differ from those for metals and ceramics, and the term degradation is most frequently used. Polymers may dissolve when exposed to a liquid solvent, or they may absorb the solvent and swell; also, electromagnetic radiation (primarily ultraviolet) and heat may cause alterations in their molecular structures.
Corrosion of metals is the spontaneous chemical (oxidative) destruction of metals under the effect of their environment. Most often it follows an electrochemical mechanism, where anodic dissolution (oxidation) of the metal and cathodic reduction of an oxidizing agent occur as coupled reactions. Sometimes a chemical mechanism is observed. Corrosion (rusting) of metals is causing huge losses to the economy. This process affects the metal structures of buildings and bridges, the equipment of chemical and metallurgical plants, river and sea vessels, underground pipelines, and other structures. In the United States, for instance, corrosion-related losses approach a figure of $100 billion per year, which is almost 5% of the gross national product. Direct losses attributable to corrosion include expenditures for the replacement of individual parts, units, entire lines or plants, and for various preventive and protective tasks (such as the application of coatings for corrosion protection). Indirect losses arise when corroded equipment leads to defective products that must be rejected; they also arise during downtime required for preventive maintenance or repair of equipment. About 30% of all steel and cast iron are lost because of corrosion. Part of this metal can be reprocessed as scrap, but about 10% is
irrevocably lost.
The significance of corrosion protection has risen sharply in recent years for a number of reasons: (1) because of efforts to reduce the metal content of parts (e.g., by using thinner metallic support structures); (2) with the use of new types of equipment and processes involving expensive equipment operated under extreme conditions, such as nuclear reactors and jet and rocket engines; and (3) in connection with the development of products having extremely thin metal films, such as printed circuit boards and integrated circuits.
Corrosion phenomena can be classified according to the type of corroding medium acting on the metal. Corrosion in nonelectrolytic media is distinguished from that in electrolytic media. The former include dry hot gases, organic liquids (e.g., gasoline), and molten metals. Electrolytic media are most diverse, and include ambient air (with moisture and other components), water (seawater, tap water) and aqueous solutions (acids, alkalies, salt solutions), moist soil (for underground pipelines, piles, etc.), melts, and nonaqueous electrolyte solutions.
Corrosion phenomena can also be classified according to the visible aspects of corrosive attack (Fig. 22.1). This may be general (continuous), affecting all of the exposed surface of a metallic object, or localized. General corrosion can be uniform and nonuniform. Depending on the width and depth of the segments affected by localized corrosion, we may speak of spot, pit (large or small), or subsurface corrosion. Often, intercrystalline corrosion is encountered, which propagates in the zones between individual metal crystallites. Cracks develop between or in individual crystals in the case of stress corrosion cracking.
For metallic materials, the corrosion process is normally electrochemical, that is, a chemical reaction in which there is transfer of electrons from one chemical species to another. Metal atoms characteristically lose or give up electrons in what is called an oxidation reaction. For example, the hypothetical metal M that has a valence of n (or n
valence electrons) may experience oxidation according to the reaction
in which M becomes an n+ positively charged ion and in the process loses its n valence
electrons; is used to symbolize an electron. Examples in which metals oxidize are
The site at which oxidation takes place is called the anode; oxidation is sometimes called
an anodic reaction.
The electrons generated from each metal atom that is oxidized must be transferred to and
become a part of another chemical species in what is termed a reduction reaction. For example, some metals undergo corrosion in acid solutions, which have a high concentration of hydrogen (H+) ions; the H+ ions are reduced as follows:
and hydrogen gas (H2) is evolved.
Any metal ions present in the solution may also be reduced; for ions that can exist
in more than one valence state (multivalent ions), reduction may occur by
in which the metal ion decreases its valence state by accepting an electron. Or a
metal may be totally reduced from an ionic to a neutral metallic state according to
Some corrosion prevention methods were treated relative to the eight forms of corrosion; however, only the measures specific to each of the various corrosion types were discussed.Now, some more general techniques are presented; these include material selection, environmental alteration, design, coatings, and cathodic protection.
Perhaps the most common and easiest way of preventing corrosion is through the judicious selection of materials once the corrosion environment has been characterized. Standard corrosion references are helpful in this respect. Here, cost may be a significant factor. It is not always economically feasible to employ the material that provides the optimum corrosion resistance; sometimes, either another alloy and/or some other measure must be used.
Changing the character of the environment, if possible, may also significantly influence corrosion. Lowering the fluid temperature and/or velocity usually produces a reduction in the rate at which corrosion occurs. Many times increasing or decreasing the concentration of some species in the solution will have a positive effect; for example, the metal may experience passivation.
Inhibitors are substances that, when added in relatively low concentrations to the environment, decrease its corrosiveness. Of course, the specific inhibitor depends both on the alloy and on the corrosive environment.There are several mechanisms that may
account for the effectiveness of inhibitors. Some react with and virtually eliminate a chemically active species in the solution (such as dissolved oxygen). Other inhibitor molecules attach themselves to the corroding surface and interfere ith either the oxidation or the reduction reaction, or form a very thin protective oating. Inhibitors are normally used in closed systems such as automobile radiators and steam boilers.
Several aspects of design consideration have already been discussed, especially with regard to galvanic and crevice corrosion and erosion–corrosion. In addition, the design should allow for complete drainage in the case of a shutdown, and easy washing. Since dissolved oxygen may enhance the corrosivity of many solutions, the design should, if possible, include provision for the exclusion of air.
Physical barriers to corrosion are applied on surfaces in the form of films and coatings. A large diversity of metallic and nonmetallic coating materials are available. It is essential that the coating maintain a high degree of surface adhesion, which undoubtedly requires some preapplication surface treatment. In most cases, the coating must be virtually nonreactive in the corrosive environment and resistant to mechanical damage that exposes the bare metal to the corrosive environment. All three material types—metals, ceramics, and polymers—are used as coatings for metals.
1.固相烧结：固态粉末在适当的温度，压力，气氛和时间条件下，通过物质与气孔之间的传质，变为坚硬、致密烧结体的过程。 液相烧结：有液相参加的烧结过程。 2.金属键:自由电子与原子核之间静电作用产生的键合力。 3.离子键：金属原子自己最外层的价电子给予非金属原子，使自己成为带正电的正离子，而非金属得到价电子后使自己成为带负电的负离子，这样正负离子靠它们之间的静电引力结合在一起。 共价键：由两个或多个电负性相差不大的原子间通过共用电子对而形成的化学键。氢键：由氢原子同时与两个电负性相差很大而原子半径较小的原子（O，F，N等）相结合而产生的具有比一般次价键大的键力。 弗兰克缺陷：间隙空位对缺陷 肖脱基缺陷：正负离子空位对的 奥氏体：γ铁内固溶有碳和(或)其他元素的、晶体结构为面心立方的固溶体。 布拉菲点阵:除考虑晶胞外形外，还考虑阵点位置所构成的点阵。 不全位错：柏氏矢量不等于点阵矢量整数倍的位错称为不全位错。 玻璃化转变温度：过冷液体随着温度的继续下降，过冷液体的黏度迅速增大，原子间的相互运动变得更加困难，所以当温度降至某一临界温度以下时，即固化成玻璃。这个临界温度称为玻璃化温度Tg。 表面能:表面原子处于不均匀的力场之中，所以其能量大大升高，高出的能量称为表面自由能（或表面能）。 半共格相界：若两相邻晶体在相界面处的晶面间距相差较大，则在相界面上不可能做到完全的一一对应，于是在界面上将产生一些位错，以降低界面的弹性应变能，这时界面上两相原子部分地保持匹配，这样的界面称为半共格界面或部分共格界面。 柏氏矢量:描述位错特征的一个重要矢量，它集中反映了位错区域内畸变总量的大小和方向，也使位错扫过后晶体相对滑动的量。 柏氏矢量物理意义： ①从位错的存在使得晶体中局部区域产生点阵畸变来说：一个反映位错性质以及由位错引起的晶格畸变大小的物理量。 ②从位错运动引起晶体宏观变形来说：表示该位错运动后能够在晶体中引起的相对位移。 部分位错：柏氏矢量小于点阵矢量的位错 包晶转变：在二元相图中，包晶转变就是已结晶的固相与剩余液相反应形成另一固相的恒温转变。 包析反应:由两个固相反应得到一个固相的过程为包析反应。 包析转变：两个一定成分的固相在恒温（T）下转变为一个新的固相的恒温反应。包析转变与包晶转变的相图特征类似，只是包析转变中没有液相，只有固相。 粗糙界面：界面的平衡结构约有一半的原子被固相原子占据而另一半位置空着，这时界面称为微观粗糙界面。 重合位置点阵：当两个相邻晶粒的位相差为某一值时，若设想两晶粒的点阵彼此通过晶界向对方延伸，则其中一些原子将出现有规律的相互重合。由这些原子重合位置所组成的比原来晶体点阵大的新点阵，称为重合位置点阵。 成分过冷；界面前沿液体中的实际温度低于由溶质分布所决定的凝固温度时产生的过冷。
期期末测试题 Ⅰ、Translate The Following Terms Into Chinese 、 1、entity concept 主题概念 2、depreciation折旧 3、double entry system 4、inventories 5、stable monetary unit 6、opening balance 7、current asset 8、financial report 9、prepaid expense 10、internal control 11、cash flow statement 12、cash basis 13、tangible fixed asset 14、managerial accounting 15、current liability 16、internal control 17、sales return and allowance 18、financial position 19、balance sheet 20、direct write-off method Ⅱ、Translate The Following Sentences Into Chinese 、 1、Accounting is often described as an information system、It is the system that measures business activities, processes into reports and communicates these findings to decision makers、 2、The primary users of financial information are investors and creditors、Secondary users include the public, government regulatory agencies, employees, customers, suppliers, industry groups, labor unions, other companies, and academic researchers、 3、There are two sources of assets、One is liabilities and the other is owner’s equity、Liabilities are obligations of an entity arising from past transactions or events, the settlement of which may result in the transfer or use of assets or services in the future、 资产有两个来源，一个就是负债，另一个就是所有者权益。负债就是由过去得交易或事件产生得实体得义务，其结算可能导致未来资产或服务得转让或使用。 4、Accounting elements are basic classification of accounting practices、They are essential units to present the financial position and operating result of an entity、In China, we have six groups of accounting elements、They are assets, liabilities, owner’s equity, revenue, expense and profit (income)、会计要素就是会计实践得基础分类。它们就是保护财务状况与实体经营
一．中古英语时期 ?Beowulf is the oldest poem in the English language, and the most important specimen (范例、典范)of Anglo-Saxon literature, and also the oldest surviving epic in the English language. ?The romance is a popular literary form in the medieval period（中世纪）. It uses verse or prose to sing knightly adventures or other heroic deeds. ?Geoffrey Chaucer, one of the greatest English poets, whose masterpiece, The Canterbury Tales（《坎特伯雷故事集》）,was one of the most important influences on the development of English literature. ?Chaucer is considered as the father of English poetry and the founder of English realism. 二．文艺复兴Renaissance ?Renaissance refers to the period between the 14th and mid-17th centuries. It marks a transition(过渡) from the medieval to the modern world. ?It started in Italy with the flowering of painting, sculpture（雕塑）and literature, and then spread to the rest of Europe. ?Humanism is the essence of Renaissance -----Man is the measure of all things. ?This was England’s Golden Age in literature. Queen Elizabeth reigned over the country in this period. The real mainstream of the English Renaissance is the Elizabethan drama. The most famous dramatists in the Renaissance England ? ?“Of Studies” is the most popular of Bacon’s 58 essays. ?Thomas More ——Utopia ?Edmund Spenser——The Faerie Queene 相关练习 ? 1. Which is the oldest poem in the English language? ? A. Utopia B. Faerie Queene ? C. Beowulf D. Hamlet ? 2. _____ is the father of English poetry. ? A. Edmund Spenser B. William Shakespeare ? C. Francis Bacon D. Geoffrey Chaucer ? 3. ____ is not a playwright during the Renaissance period on England. ? A. William Shakespeare B. Geoffrey Chaucer ? C. Christopher Marlowe D. Ben Johnson 三．莎士比亚William Shakespeare ?“All the world 's a stage, and all the men and women merely players.”——William Shakespeare ?William Shakespeare is considered the greatest playwright in the world and the finest poet who has written in the English language. Shakespeare understood people more than any other writers. He could create characters that have
常用1000个单词的机电英语 able [`eibl] adj.能够 abnormal [b`n:ml] adj.异常 abort [`b:t]中断,停止 absent [`bsnt] adj. 不在的，缺少的 acceleration [k.sel`rein] n. 加速，加速度access [`kses] vt. 存取 action [`kn]. 动作 actuator [`ktjueit]n.操作(执行)机构,执行器 address [`dres] 地址 adjust [`dst] 调整，校正 adjustable wrench 活扳手 adjustable [`dstbl] 可调整的 adjusting screw 调整螺钉 adjustment [`dstment] 调节、调节装置 air compressor空压机 [km`pres] 压缩机 air exhaust fan排气扇[ig`z:st] 排气，抽完 air [e]风，空气 alarm [`lam] 报警 align [`lain] 定位，对准，调整 alternating current AC 交流电 [:l`t:nt] 轮流，交替ambient temp 环境温度 ambient [`mbit] 周围的，环境的 ammeter [`mit] n. 电流表，安培计 amp [mp] n. 安培 ampere [`mp] n. 安培 amplifier [`mplifai] n. 放大器，扩音器 analog input [`nlg] 模拟量输入 analog output 模拟量输出 analog signal 模拟信号[`nlg] [`signl] analog [`nlg] 模拟 analog-to-digital A/D 模数转换 [`diditl] angle valve 角伐 angle [`gl] 角度 application program 应用程序 [.pli`kein] 请求,应用 arc [a:k] 电弧，弧光 area [`eri] 面积，区域 arrester [e`rest] 避雷器 assemble line装配线，生产线[`sembl] assemble [`sembl] 安装，组装 asynchronous motor 异步马达 [ei`sins] atomizing [`tms.fi] 雾化
材料科学基础常用英语词汇 材料的类型Types of materials, metals, ceramics, polymers, composites, elastomer 部分材料性质复习Review of selected properties of materials, 电导率和电阻率conductivity and resistivity, 热导率thermal conductivity, 应力和应变stress and strain, 弹性应变elastic strain, 塑性应变plastic strain, 屈服强度yield strength, 最大抗拉强度ultimate tensile strength, 最大强度ultimate strength, 延展性ductility, 伸长率elongation, 断面收缩率reduction of area, 颈缩necking, 断裂强度breaking strength, 韧性toughness, 硬度hardness, 疲劳强度fatigue strength, 蜂窝honeycomb, 热脆性heat shortness, 晶胞中的原子数atoms per cell,
点阵lattice, 阵点lattice point, 点阵参数lattice parameter, 密排六方hexagonal close-packed, 六方晶胞hexagonal unit cell, 体心立方body-centered cubic, 面心立方face-centered cubic, 弥勒指数Miller indices, 晶面crystal plane, 晶系crystal system, 晶向crystal direction, 相变机理Phase transformation mechanism: 成核生长相变nucleation–growth transition, 斯宾那多分解spinodal decomposition, 有序无序转变disordered-order transition, 马氏体相变martensite phase transformation，成核nucleation, 成核机理nucleation mechanism, 成核势垒nucleation barrier, 晶核，结晶中心nucleus of crystal, （金属组织的）基体quay, 基体，基块，基质，结合剂matrix, 子晶，雏晶matted crystal, 耔晶，晶种seed crystal, 耔晶取向seed orientation,
《财会专业英语》期终试卷 I.Put the following into corresponding groups. (15 points) 1.Cash on hand 2.Notes receivable 3.Advances to suppliers 4. Other receivables 5.Short-term loans 6.Intangible assets 7.Cost of production 8.Current year profit 9. Capital reserve 10.Long-term loans 11.Other payables 12. Con-operating expenses 13.Financial expenses 14.Cost of sale 15. Accrued payroll II.Please find the best answers to the following questions. (25 Points) 1. Aftin Co. performs services on account when Aftin collects the account receivable A.assets increase B.assets do not change C.owner’s equity d ecreases D.liabilities decrease 2. A balance sheet report . A. the assets, liabilities, and owner’s equity on a particular date B. the change in the owner’s capital during the period C. the cash receipt and cash payment during the period D. the difference between revenues and expenses during the period 3. The following information about the assets and liabilities at the end of 20 x 1 and 20 x 2 is given below: 20 x 1 20 x 2 Assets $ 75,000 $ 90,000 Liabilities 36,000 45,000 how much the owner’sequity at the end of 20 x 2 ? A.$ 4,500 B.$ 6,000 C.$ 45,000 D.$ 43,000
自动化专业英语常用词汇 acceleration transducer 加速度传感器 accumulated error 累积误差 AC-DC-AC frequency converter交-直-交变频器 AC (alternating current) electric drive 交流电子传动 active attitude stabilization 主动姿态稳定 adjoint operator 伴随算子 admissible error 容许误差 amplifying element 放大环节 analog-digital conversion 模数转换 operational amplifiers运算放大器 aperiodic decomposition 非周期分解 approximate reasoning 近似推理 a priori estimate 先验估计 articulated robot 关节型机器人 asymptotic stability 渐进稳定性 attained pose drift 实际位姿漂移 attitude acquisition 姿态捕获 AOCS (attitude and orbit control system) 姿态轨道控制系统attitude angular velocity 姿态角速度 attitude disturbance 姿态扰动 automatic manual station 自动-手动操作器 automaton 自动机 base coordinate system 基座坐标系 bellows pressure gauge 波纹管压力表 gauge测量仪器
材料科学基础专业词汇:第一章晶体结构 原子质量单位Atomic mass unit (amu) 原子数Atomic number 原子量Atomic weight 波尔原子模型Bohr atomic model 键能Bonding energy 库仑力Coulombic force 共价键Covalent bond 分子的构型molecular configuration 电子构型electronic configuration 负电的Electronegative 正电的Electropositive 基态Ground state 氢键Hydrogen bond 离子键Ionic bond 同位素Isotope 金属键Metallic bond 摩尔Mole 泡利不相容原理Pauli exclusion principle 元素周期表Periodic table 原子atom 分子molecule 分子量molecule weight 极性分子Polar molecule 量子数quantum number 价电子valence electron 范德华键van der waals bond 电子轨道electron orbitals 点群point group 对称要素symmetry elements 各向异性anisotropy 原子堆积因数Atomic packing factor (APF) 体心立方结构body-centered cubic (BCC) 面心立方结构face-centered cubic (FCC) 布拉格定律bragg’s law 配位数coordination number 晶体结构crystal structure 晶系crystal system 晶体的crystalline 衍射diffraction 中子衍射neutron diffraction 电子衍射electron diffraction 晶界grain boundary 六方密堆积hexagonal close-packed (HCP) 鲍林规则Pauling’s rules NaCl型结构NaCl－type structure CsCl型结构Caesium Chloride structure 闪锌矿型结构Blende-type structure 纤锌矿型结构Wurtzite structure 金红石型结构Rutile structure 萤石型结构Fluorite structure 钙钛矿型结构Perovskite-type structure 尖晶石型结构Spinel-type structure 硅酸盐结构Structure of silicates 岛状结构Island structure 链状结构Chain structure 层状结构Layer structure 架状结构Framework structure 滑石talc 叶蜡石pyrophyllite 高岭石kaolinite 石英quartz 长石feldspar 美橄榄石forsterite 各向同性的isotropic 各向异性的anisotropy 晶格lattice 晶格参数lattice parameters 密勒指数miller indices 非结晶的noncrystalline 多晶的polycrystalline 多晶形polymorphism 单晶single crystal 晶胞unit cell 电位electron states (化合)价valence
ACCOUNTING ENGLISH Middle-of-term Test Papers PartⅠ.Translating the following terms 1、Notes to financial statements 2、Accounting elements 3、Variable costs 4、Economic entity 5、Depreciation expense 6、Deferred income taxes 7、Nominal accounts 8、ROA 9、LIFO 10、Work in process 11、现金收支 12、原材料 13、制造费用 14、相关性 15、持续经营 16、复式记账 17、优先股 18、预付费用 19、购货退回与折让 20、永续盘存制
PartⅡ.True or False 1、 The accounting process generates financial reports for both “internal ”and “external”users. 2、The balance sheet reflects the basic accounting equation and the means of financing the organization's assets. 3、The existence of Accounts Receivable on the Balance Sheet indicates that the company has one or more creditors. 4、Liabilities are classified and presented in increasing order of liquidity. 5、Working capital equals current assets less current liabilities. 6、Declaration of dividends reduces the retained earnings portion of the owners' equity of the corporation and creates a liabilities called Dividends Payable. 7、A chart of accounts is a listing of the titles of all accounts. 8、The cash basis of accounting often violates the matching rule. 9、Closing entries convert real and nominal accounts to zero balance. 10、The work sheet is published with the balance sheet and income statement, as a supplementary statement. 11、A company's sustainable growth rate is the highest growth rate in sales it can attain without issuing new stock. 12、Only rapidly growing firms have growth management problems.
Fundamentals of Materials Science 材料科学基础名词与术语 第一章绪论 metal: 金属 ceramic: 陶瓷polymer: 聚合物Composites: 复合材料Semiconductors: 半导体Biomaterials: 生物材料 Processing: 加工过程 Structure: 组织结构 Properties: 性质 Performance: 使用性能 Mechanical properties: 力学性能 Electrical properties: 电性能 Thermal behavior: 热性能 Magnetic properties: 磁性能 Optical properties: 光性能 Deteriorative characteristics: 老 化特性 第二章原子结构与原子键 Atomic mass unit (amu): 原子质量单位 Atomic number: 原子数 Atomic weight: 原子量 Bohr atomic model: 波尔原子模型Bonding energy: 键能 Coulombic force: 库仑力 Covalent bond: 共价键 Dipole (electric): 偶极子electronic configuration: 电子构型electron state: 电位 Electronegative: 负电的 Electropositive: 正电的 Ground state: 基态 Hydrogen bond: 氢键 Ionic bond: 离子键 Isotope: 同位素 Metallic bond: 金属键 Mole: 摩尔 Molecule: 分子 Pauli exclusion principle: 泡利不相 容原理 Periodic table: 元素周期表 Polar molecule: 极性分子 Primary bonding: 强键 Quantum mechanics: 量子力学 Quantum number: 量子数 Secondary bonding: 弱键 valence electron: 价电子 van der waals bond: 范德华键 Wave-mechanical model: 波粒二象 性模型 第三章金属与陶瓷的结构 Allotropy: 同素异形现象 Amorphous: 无定形 Anion: 阴离子 Anisotropy: 各向异性 atomic packing factor(APF): 原子堆积因数body-centered cubic (BCC): 体心立方结构Bragg’s law: 布拉格定律 Cation: 阳离子 coordination number: 配位数 crystal structure: 晶体结构 crystal system: 晶系 crystalline: 晶体的 diffraction: 衍射 face-centered cubic (FCC): 面心立方结构第五章晶体缺陷 Alloy: 合金 A metallic substance that is composed of two or more elements. 由两种及以上元素组成的金属材料。 Weight percent (wt%)：质量百分数 Concentration specification on the basis of weight (or mass) of a particular element relative to the total alloy weight (or mass). Stoichiometry: 正常价化合物 For ionic compounds, the state of having exactly the ratio of cations to anions speci-fied by the chemical formula. 在离子化合物中，正、负离子的比例严格遵守化学公式定义的化合价关系。 Imperfection: 缺陷，不完整性 A deviation from perfection; normally applied to crystalline materials wherein there is a deviation from atomic/molecular order and/or continuity. 对完美性的偏离，在材料科学领域中通常指晶体材料中原子/分子在排列顺序/连续性上的偏离。 Point defect: 点缺陷 A crystalline defect associated with one or, at most, several atomic sites. 一种仅波及一个或数个原子的晶体缺陷。 Vacancy: 空位 A normally occupied lattice site from which an atom or ion is missing. 一个缺失原子或离子的晶格节点位置。 Vacancy diffusion: 空位扩散
一、选择题 1、The four-stroke cycle operates in which order __C__. A. intake, exhaust, power, compression B. intake, power, compression, exhaust C. intake, compression, power, exhaust 2、With the piston at the bottom of the cylinder, the ___C____ valve ___________ to allow the burned exhaust gas to be expelled to the exhaust system. A.intake, closes B. exhaust, closes C. exhaust, opens 3、A car engine's job is to ___B__ A. Convert fuel into heat B. Convert fuel into motion C. Convert fuel into exhaust 4、When the crankshaft completes four revolutions for a four-cycle engine, each cylinder will have gone through ____B____intake stroke(s). A.one B. two C. Three 5、___C___ is the life-blood of the engine. A. gas B. water C. Oil 6、What is the core of a car's engine___C___ A.The spark plug B. exhaust C. The cylinder 7、What determines the size and the placement of the engine block____C____ A. The number of spark plugs B. The number of pistons C. The number of cylinders 8、In the standard engine, each cylinder has ___A___. A.four valves B. two valves C. one valve 9、A crankshaft's job in an engine is to ___C___ A. Deliver fuel to the cylinders B. Keep cylinder heads in place C. Change linear motion into rotational motion 10、The _____C___ system on an internal combustion engine provides the spark that ignites the combustible air/fuel mixture in the combustion chamber. A.starting B. fuel C. igniting 二、填空题 1.Today’s average car contains more than 15000 separate, individual parts that must work together. These parts can be grouped into four major categories: body，engine，chassis and electrical system . 2.The direction motion of vehicle is controlled by a steering system. A basic steering system has 3 main parts: steering control mechanism ，steering gear and steering linkage mechanism which connecting wheels and steering gear . 3.The location of the driving axle determines whether the vehicle is classified as rear-wheel?drive ，front-wheel?drive ，four-wheel?drive and all-wheel drive. 4.The modern clutch9 is a single plate, dry disc . It consists of five major parts: flywheel, clutch disc , pressure plate assembly, throw-out bearing , and clutch linkage.
专业英语期末考试试卷A卷标准答案及评分标准（2009-2010第二学期） 一、Translate the following speciality vocabulary into Chinese (20×1=20) 标准答案：1.电气工程 2. 正电荷 3 .信道 4.家庭自动化 5.桌面应用软件 6.下降沿 7.波特率 8.红外线传感器9 数字信号10.激光技术 11光纤12.微处理器13振荡器14.半导体15.远程控制 16触发器17.阴极射线管18 代码错误19.波导管20.通信工程 评分标准：得分=做对的个数×1 二、Translate the following speciality vocabulary into English(10×1=10) 1.circuit 2.voltage 3.diode 4.triode 5.microwave oven 6.watchdog 7.sensor或transducer 8.current 9.transistor 10. magnifier或amplifier 评分标准：得分=做对的个数×1 四、Multiple choices. (2×10=20） 1-5 BCDBD 6-10 BAAAC 评分标准：得分=做对的个数×2 五、Translate the following sentences into Chinese (5×2=10) 1、电源有两种：电流源与电压源。 2、电子元器件分为有源元件与无源元件两类。 3、激光技术是用来测量物体的存在、传感器到物体之间的距离以及物体尺寸的一种技术。 4、计算机的“大脑”被称为微处理器。 5、串行口有四种工作模式。 六、Choose the right statements according to the following passage .（true(T) or false (F) (5×2=10)） P1: 1-5 T F T F T 评分标准：得分=做对的个数×2 七、Reading Comprehension(5×2=10)） 1-5 B C A D C 评分标准：得分=做对的个数×2
液压气动专业常用英语词汇 一、阀类 Solenoid valve 电磁阀 Check valve 单向阀 Cartridge valve 插装阀 Sandwich plate valve 叠加阀 Pilot valve 先导阀 Pilot operated check valve 液控单向阀Sub-plate mount 板式安装 Manifold block 集成块 Pressure relief valve 压力溢流阀 Flow valve 流量阀 Throttle valve 节流阀 Double throttle check valve 双单向节流阀Rotary knob 旋钮 Rectifier plate 节流板 Servo valve 伺服阀 Proportional valve 比例阀 Position feedback 位置反馈Progressive flow 渐增流量 De-energizing of solenoid 电磁铁释放 二、介质类 Phosphate ester (HFD-R) 磷酸甘油酯Water-glycol (HFC) 水-乙二醇Emulsion 乳化液 Inhibitor缓蚀剂 Synthetic lubricating oil 合成油 三、液压安装工程 Contamination 污染 Grout 灌浆 Failure 失效 Jog点动 Creep爬行 Abrasion 摩擦 Retract（活塞杆）伸出 Extension （活塞杆）缩回 Malfunction 误动作 Pickling 酸洗 Flushing 冲洗 Dipping process 槽式酸洗 Re-circulation 循环 Passivity 钝化Nitric acid 柠檬酸 Argon 氩气 Butt welding 对接焊 Socket welding 套管焊 Inert gas welding 惰性气体焊 四、管接头 Bite type fittings 卡套式管接头 Tube to tube fittings 接管接头 union 直通接管接头 union elbow 直角管接头 union tee 三通管接头 union cross 四通管接头 Mal stud fittings 端直通管接头 Bulkhead fittings 长直通管接头 Weld fittings 焊接式管接头 Female connector fittings 接头螺母Reducers extenders 变径管接头 Banjo fittings 铰接式管接头 Adjustable fittings/swivel nut 旋转接头 五、伺服阀及伺服系统性能参数Dynamic response 动态频响 DDV-direct drive valve 直动式伺服阀NFPA-National Fluid Power Association 美国流体控制学会 Phase lag 相位滞后 Nozzle flapper valve 喷嘴挡板阀 Servo-jet pilot valve 射流管阀 Dither 颤振电流 Coil impedance 线圈阻抗 Flow saturation 流量饱和 Linearity 线形度 Symmetry 对称性 Hysterics 滞环 Threshold 灵敏度 Lap 滞后 Pressure gain 压力增益 Null 零位 Null bias 零偏 Null shift 零飘 Frequency response 频率响应 Slope 曲线斜坡