材料科技英语第一章part 2 unit 13
科技英语课文翻译
Unit 1大规模研究发现：地球的“健康”每况愈下有史以来对地球进行的最大规模的科学分析结果表明，地球上的许多生态系统都达不到标准。
由联合国主持的《千年生态系统评估综合报告》指出，由于不可持续的使用，地球上将近三分之二的用来维持生命的生态系统（包括干净的水源、纯净的空气以及稳定的气候）正遭受破坏。
以上大部分的破坏都是人类在过去的半个世纪里造成的。
据报告分析，随着人类对食物、淡水、木材、纤维以及燃料等资源的需求日趋激增，环境发生了极大的变化，引发了诸如滥伐森林、化学污染等问题。
因此，该报告的作者警告说，照此下去，本已岌岌可危的生态环境将会在21世纪的上半叶进一步恶化。
这项历史性的研究由来自世界95个国家的政府部门以及民间组织的1,300多位科学家共同完成。
四年来，他们考察了地球上许多生物的生长环境、物种以及将他们联系起来的生态体系。
联合国环境规划署对该报告进行了编辑整理并于昨天在中国北京公布了研究结果。
在公布该报告的新闻发布会上，联合国秘书长科菲·安南指出：“只有了解环境及其运作过程，我们才能制定出必要的措施加以保护它。
”他还说，“只有珍惜所有宝贵的自然资源和人类资源，我们才有希望去建设一个可持续发展的未来。
”对社会经济的影响该报告对自然界的大部分生物多样性持悲观态度，地球上可能有10%—30%的哺乳动物，鸟类以及两栖动物濒临灭绝。
这次大规模生态调查是根据安南的《千年发展目标》展开的，该发展目标是由联合国发起的，旨在2015年之前大幅减少饥饿与极度贫困等社会经济问题。
总部位于内罗毕的联合国环境规划署执行主席克劳斯·托普弗说：“从某些方面来说，《千年生态系统评估综合报告》让我们首次认识到生态系统服务功能的经济价值，并使我们对尊重和保护地球生命维护系统有了新的见解。
”目前由于人类社会对地球环境的开发利用，食物供应不断增加，然而增长的速度仍然太慢，难以完成联合国制定的在2015年之前消除全球一半饥饿人口的目标。
科技英语课文翻译1-7
参考译文Unit 1课文A石油1油，和煤一样，存在于沉积岩中，而且可能由死去很长时间的生物有机体形成。
含有石油的岩石几乎都来源于海洋，所以形成石油的有机物一定是海洋生物，而不是树木。
2 石油，并不是来自于逐渐积聚的木质物质，而可能是来自于逐渐积聚的海洋生物的脂肪物质。
比如浮游生物：大量浮游在海水表层的单细胞生物。
3 有机物的脂肪物质主要由碳氢原子组成，因此并不需要太多的化学变化就可以形成石油。
生物有机体只需在缺氧的条件下沉积到海湾浅水处的淤泥里。
其脂肪不是分解腐烂，而是逐渐积聚，并在深层的淤泥里圈闭起来，进而经过细微的原子重组，最终形成石油。
4 油比水轻，呈液态，会经由上方覆盖的孔隙性岩石向上渗透，在地球上有些地区到达表层，古人将这些表层石油称为沥青、柏油或异庚烷。
在古代和中世纪，这些石油油苗常被看作药品而不是燃料。
5 当然，表层的油苗数量很少。
而石油油藏上方有时覆盖的是非孔隙性岩石。
石油向上渗透抵达该岩石，然后在岩石下方逐渐积聚形成油层。
若在上方的岩石上钻个孔，石油就可以通过该孔向上迁移。
有时压力过大，石油会向高空喷出。
1859年在宾夕法尼亚州，由埃德温·德雷克成功打出第一口井。
6 如果可以发现一个合适的地点（勘探人员已经识别出地下可能圈闭有石油的地层结构），那么就很容易抽取这一液体燃料，这要比派人到地下把大块的固体煤炭砍成小块要容易得多。
而且一旦获得石油，可以通过地上管道运输，而不必像煤一样，由运货车经过繁重的装卸任务来运输。
7 石油便于抽取，易于运输，促进了石油的应用。
石油可以蒸馏成不同的馏分，每种馏分均由特定大小的分子组成，分子越小，该馏分就越容易蒸发。
8 到19世纪下半叶，最重要的石油馏分是由中等大小的分子构成的煤油，它不易蒸发，被用于照明。
9 然而，到19世纪末人们研制出了内燃机。
内燃机是通过在汽缸里将空气与可燃气体混合，产生爆炸来提供动力的。
最便利的可燃气体是汽油——石油的又一馏分，由小分子构成，容易蒸发。
科技英语阅读课后参考答案-Unit1,3
科技英语阅读课后参考答案-Unit1,3Unit 1 MathematicsPart I EST Reading Reading 1Warm-up Questions: Work in pairs and discuss the following questions. 1. Who is Bertrand Russell? Bertrand Arthur William Russell (b.1872 – d.1970) was a British philosopher, logician, essayist and social critic best known for his work in mathematical logic and analytic philosophy. His most influential contributions include his defense of logicism (the view that mathematics is in some important sense reducible to logic), his refining of the predicate calculus introduced by Gottlob Frege (which still forms the basis of most contemporary logic), his defense of neutral monism (the view that the world consists of just one type of substance that is neither exclusively mental nor exclusively physical), and his theories of definite descriptions and logical atomism. Russell is generally recognized as one of the founders of modern analytic philosophy, and is regularly credited with being one of the most important logicians of the twentieth century. 2. What is Russell’s Paradox? Russell discovered the paradox that bears his name in 1901, while working on his Principles of Mathematics (1903). The paradox arises in connection with the set of all sets that are not members of themselves. Such a set, if it exists, will be a member of itself if and only if it is not a member of itself. The paradox is significant since, using classical logic, all sentences are entailed by a contradiction. Russell's discovery thus prompted a large amount of work in logic, set theory, and the philosophy and foundations of mathematics. 3. What effect did Russell’s Paradox have on Gottlob Fregg’s system? At first Frege observed that the consequences of Russell’s paradox are not immediately clear. For example, “Is it always permissible to speak of the extension of a concept, of a class? And if not, how do we recognize the exceptional cases? Can we always infer from the extension of one concept’s coinciding with that of a second, that every object which falls under the first concept also falls under the second? Because of these kinds of worries, Frege eventually felt forced to abandon many of his views. 4. What is Russell’s response to the paradox? Russell's own response to the paradox came with the development of his theory of types in 1903. It was clear to Russell that some restrictions needed to be placed upon the original comprehension (or abstraction) axiom of naive set theory, the axiom that formalizes the intuition that any coherent condition may be used to determine a set (or class). Russell's basic idea was that reference to sets such as the set of all sets that are not members of themselves could be avoided by arranging all sentences into a hierarchy, beginning with sentences about individuals at the lowest level, sentences about sets of individuals at the next lowest level,1sentences about sets of sets of individuals at the next lowest level, and so on Using a vicious circle principle similar to that adopted by the mathematician Henri Poincaré, and his own so-called "no class" theory of classes, Russell was able to explain why the unrestricted comprehension axiom fails: propositional functions, such as the function "x is a set," may not be applied to themselves since self-application would involve a vicious circle. On Russell's view, all objects for which a given condition (or predicate) holds must be at the same level or of the same "type." 5. Have you ever heard of Zermelo-Fraenkel set theory.? Can you give an account of it? Contradictions like Russell’s paradox arose from what was later called the unrestricted comprehension principle: the assumption that, for any property p, there is a set that contains all and only those sets that have p. In Zermelo’s system, the comprehension principle is eliminated in favour of several much more restrictive axioms: a. Axiom of extensionality. If two sets have the same members, then they are identical. b. Axiom of elementary sets. There exists a set with no members: the null, or empty, set. For any two objects a and b, there exists a set (unit set) having as its only member a, as well as a set having as its only members a and b. c. Axiom of separation. For any well-formed property p and any set S, there is a set, S1, containing all and only the members of S that have this property. That is, already existing sets can be partitioned or separated into parts by well-formed properties. d. Power-set axiom. If S is a set, then there exists a set, S1, that contains all and only the subsets of S. e. Union axiom. If S is a set (of sets), then there is a set containing all and only the membersof the sets contained in S. f. Axiom of choice. If S is a nonempty set containing sets no two of which have common members, then there exists a set that contains exactly one member from each member of S. g. Axiom of infinity. There exists at least one set that contains an infinite number of members. With the exception of (b), all these axioms allow new sets to be constructed from already-constructed sets by carefully constrained operations; the method embodies what has come to be known as the “iterative” conception of a set. /doc/a90df7ed551810a6f524860e.html/entries/russell/ Section C Post-reading TaskReading Comprehension1. Directions: Work on your own and fill in the blanks with the main idea. Part 1 (Para. 1): Brief introduction to Russell’s paradox Part 2 (Paras. 2-5): The effect of Russell’s paradox on Gottlob Frege’s system.2Para. 2: Russell’s paradox dealt a heavy blow to Frege’s attempts to develop a foundation for all of mathematics using symbolic logic. Para. 3: An illustration of Russell’s paradox in terms of sets Para. 4: Contradiction found in the set. Para. 5: Frege noticed the devastating effect of Russell’s paradox on his system and inability to solve it. Part 3 (Paras. 6-8): Solutions offered by mathematicians to Russel’s paradox Para. 6: Russell’s own response to the paradox with his "theory of types."Para. 7: Zermelo's solution to Russell's paradox Para. 8: What became of the effort to develop a logical foundation for all of mathematics? Part 4 (Para. 9): Correspondence between Russell and Frege on the paradox 2. Directions: Work in pairs and discuss the following questions. 1) What is the basic idea of Russell’s paradox? 2) How to explain Russell’s paradox in terms of sets? 3) Can you explain the contradiction found in the sets related to Russell’s paradox 4) Is Russell’s own response to the paradox workable? 5) Do you know Zermelo-Fraenkel set theory? (open) 3. Directions: Read the following passage carefully and fill in the blanks with the words you’ve learned in the text. Russell's own response to the paradox came with the development of his theory of types in 1903. It was clear to Russell that some restrictions needed to be placed upon the original comprehension (or abstraction) axiom of naive set theory, the axiom that formalizes the intuition that any coherent condition may be used to determine a set (or class). Russell's basic idea was that reference to sets such as the set of all sets that are not members of themselves could be avoided by arranging all sentences into a hierarchy, beginning with sentences about individuals at the lowest level, sentences about sets of individuals at the next lowest level, sentences about sets of sets of individuals at the next lowest level, and so on. Using a vicious circle principle similar to that adopted by the mathematician Henri Poincaré, and his own so-called "no class" theory of classes, Russell was able to explain why the unrestricted comprehension axiom fails: propositional functions, such as the function "x is a set," may not be applied to themselves since self-application would involve a vicious circle. On Russell's view, all objects for which a given condition (or predicate) holds must be at the same level or of the same "type."Vocabulary and Structure31. Word-building Directions: Give the correct form of the word according to the indication in the brackets. Then complete the sentences using the right form for each word. Use each word once. discover— (suffix) logic— (suffix) correspond—(suffix) describe—(suffix) contradict— (suffix) symbol—(suffix) form—(suffix) develop—(suffix) able—(prefix) equal—(suffix)1) The math may not have been new, but Duchin enjoyed the process of_________, and she got to work collaboratively with half a dozen other math whizzes.( discovery) 2) Packages can be sealed and can contain personal _________if it relates to the contents of the package.( correspondence) 3) New research indicates that the brain region may prefer_________ notation to other numeric representations .( symbolic) 4) To do this, an ideal model based on the _________ paradigm was constructed and then compared with a neutral model reflecting the further education system as it existed before the Act took effect.( equality) 5) Is this not in flagrant _________to Einstein's rule that signals do not travel faster than the velocity of light?( contradiction) 6) Sequential organization has the major advantage that the records are stored in a _________ order, presumably that sequence to which the records are normally required for printing and for soft copy reports.( logical) 7) The mathematical _________ of a zero-sum two-person game is not difficult to construct, and determining the optimal strategies and the value of the game is computationally straightforward.( description) 8) The proof we now know required the_________ unknown in Fermat's time.( development) of an entire field of mathematics that was9) Williams adds that many courses in geometry, “the one high school class that demands _________ reasoning,” have already been “gutted” and are no longer proof-based.( formal) 10) The concept of total aircraft ownership will become increasingly important should the traditional trade structure be _________to cover the expanse of technologies economically.( unable) 2. Directions: Complete the sentences with the words given in the brackets. Change the form if necessary. 1) The key to unraveling such apparent paradoxes is to characterize the initial set of possibilities ("initial" meaning before you receive any extra information) and then to eliminate possibilities based on that extra information. (base) 42) Indeed, this separation of meaning is reflected by the definition of "weak" in the OALD, with a distinct sense reserved for its use when pertaining to that of solutions (definition) 3) The resulting radical pollution control programme outlined by Nixon, calling for a 90 per cent reduction in vehicle emissions by 1980, not only led to him being credited (albeit briefly) as policy initiator of an environmental clean-up but also provided him with the chance to deal a blow to one of his most important opponents in the 1972 elections, Edmund Muskie (blow) 4) Singapore's continuing investments in education and training has brought a tenfold increase in our pool of Information Technology professionals and the Singapore worker has been consistently rated by BERI as the world's best in terms of technical skills, attitude and productivity. (term) 5) In this work he was led to topology, a still new kind of mathematics related to geometry, and to the study of shapes (compact manifolds) of all dimensions. (lead) 6) If there is no allowable string which spans the whole graph, then we can search in the same way as described above, but wherever the required path does not exist in the tree, check if that position in the tree is flagged for end-of-word (way) 7) During the past century, steps forward in physics have often come in the form of newly found particles; in engineering, more complex devices; in astronomy, farther planets and stars; in biology, rarer genes; and in chemistry, more useful materials and medications. (form) 8) A second reason for measurements is the more theoretical, put by Love as " the discovery of numerical relations between the quantities that can be measured to serve as a basis for the inductive determination of the form of the intrinsic energy function. " (serve) 9) Thus the optimum conditions for coastal terrace development would seem to be areas with small tidal ranges. Finally, tidal range is an important factor in the generation of tidal currents which may locally become of geomorphological importance (become) 10) The original double entrance doors to the booking hall had been replaced by an utterly incongruous picture window as had adjacent booking hall and waiting room windows. (replace) 3. Directions: Reorder the disordered parts of a sentence to make a complete sentence. 1) A simpleway to describe topology is as a 'rubber sheet geometry' — topologists study those properties of shapes that remain the same when the shapes are stretched or compressed. 2) Since the mid-1990s scientists have floated the idea that representations of numeric quantities, whether expressed as digits or as written words, are codified by the parietal cortex, a higher-processing region in the brain located just above the forehead. 3) As activity was monitored, located just above the forehead ,researchers noted changes under the assumption that the brain reduces activity as it becomes accustomed to a stimulus and then reactivates when a novel stimulus is presented. 4) That has not stopped physicists from devising new algorithms for the devices, which can calculate a lot faster than ordinary computers—in fact, exponentially faster, in quite a literal5sense. 5) Such a device would be made of metamaterial, a thicket of metal rings or other shapes that bends light in funny ways. 4. Directions: Change the following sentences into nominalized ones. 1) The passage of night could be marked by the appearance of 18 of these stars. 2) The full proof of Fermat's Last Theorem is contained in these two papers. 3) The concept of fixed-length hours, however, did not originate until the Hellenistic period. 4) There is a probability that my first sock is red because only one of the remaining three socks is red. 5) The importance of accurate data in quantitative modeling is central to using Bayes's theorem to calculate the probability of the existence of God.Discourse Understanding1. C. A "3 percent margin of error" means that there is a 95 percent chance that the survey result will be within 3 percent of the population value.2. E. How is it that a survey of only 1,000 people can reach this level of accuracy?3. G. The margin of error depends inversely on the square root of the sample size.4. A. The margin of error is a mathematical abstraction, and there are a number of reasons why actual errors in surveys are larger.5. F. Finally, the 3 percent margin of error is an understatement because opinions change.Reading 2 (/doc/a90df7ed551810a6f524860e.html/article.cfm?id=mandelbrot-set-1990-hor gan) Section A Pre-reading TaskWarm-up Questions /doc/a90df7ed551810a6f524860e.html/article.cfm?id=mandelbrot-set-1990 1. Who discovered the Mandelbrot set? This is not a trick question, not easy to answer. Many people including Mandelbrot have laid claim to the discovery. 2. Why was the set named after Benoit B. Mandelbrot? The set is named after Benoit B. Mandelbrot, a mathematician at the IBM Thomas J. Watson Research Center because he coined the term fractal to describe phenomena (such as coastlines, snowflakes, mountains and trees) whose patterns repeat themselves at smaller and smaller scales. 3. Why has there been so much controversy about who discovered the Mandelbrot set?6Mandelbrot claims that he and he alone discovered the Mandelbrot set, but there are other mathematicians who have challenged his claim. 4. What did the challengers say about Mandelbrot’s claim of discovery? Two mathematicians said that they independently discovered and described the set at about the same time as Mandelbrot did. And another mathematician also asserted that his work on the set not only predated Mandelbrot's efforts but also helped to guide them 5. Why did some professors support Mandelbrot’s claim? Mandelbrot deserves to have the set named after him, because his efforts brought the set to the attention of both the public and of the pure-mathematics community.Section C Post-reading TaskReading and Understanding1. Choose the best summary of the passage. C A B D2. Complete the sentences based on the text. 1) The term Mandelbrot set is used to refer both to a general class of_________________ and to a particular instance of such a set. （fractal sets） 2) 2.In general, a Mandelbrot set marks the set of points in the _________________ such that the corresponding Julia set is connected and not computable. （complex plane） 3) "The" Mandelbrot set is the set obtained from the _________________ z_(n+1)==z_n︿2+c with z_0==c, where points in the complex plane for which the orbit of z_n tend to infinity are in the set. （quadratic recurrence equation） does not4) Setting z_0 equal to any point in the set that is not a _________________ gives the same result. （periodic point） 5) The Mandelbrot set was originally called a _________________ by Mandelbrot. J. Hubbard and A. Douady proved that the Mandelbrot set is connected（ molecule） /doc/a90df7ed551810a6f524860e.html/11901033_d.html Language in Use1. Match the Chinese in the left column with the English in the right column. 迭代函数 iterative function 优先权之争 priority battle 分形特征 fractal properties7有意义 make sense 以越来越⼩的规模重复同⼀模式 patterns repeat themselves at smaller and smaller scales 混沌理论chaos theory 季刊 a quarterly journal 数学界 the mathematics community 波纹线 crisp lines 会议公报 proceedings of a conference 2. Join the following short sentences into longer ones. e.g. a. A fractal is generally a rough or fragmented geometric shape . b. The shape can be subdivided in parts. c. each part is (at least approximately) a reduced-size copy of the whole, a property called d. each part has a property of self-similarity. e.g. A fractal is generally "a rough or fragmentedgeometric shape that can be subdivided in parts, each of which is (at least approximately) a reduced-size copy of the whole", a property called self-similarity. 1) In addition to coining the term "fractal" to describe objects and surfaces which are irregular at various dimensions of scale, he also introduced such concepts as "fractal dimensions" and the particular fractal known as the Mandelbrot set, frequently represented with the mathematical formula z → z2 + c. 2) It appeared that things were settling into a pleasant and fruitful routine, with his school lessons supplemented by long talks with his uncle about classical analysis, the iterative work of Pierre Fatou and the equally fascinating Julia Sets generated by Gaston Julia 3) Just as the youthful Mandelbrot had passed his college entrance exams by translating algebraic problems into geometrical problems, and solving them by intuitively deducing the "perfected" shape, he here realized there was something deeper, something mathematical, behind these strange patterns. 4) But the beauty in Mandelbrot's models was not that they generated a deceitful randomness, but that they could generate graphed data whose visual pattern accurately mimicked the visual patterns created by real phenomena。
材料科学与工程专业英语1-18单元课后翻译答案
Unit 1 Translation.1."材料科学〞涉与到研究材料的结构与性能的关系.相反,材料工程是根据材料的结构与性质的关系来涉与或操控材料的结构以求制造出一系列可预定的性质.2.实际上,所有固体材料的重要性质可以分为六类：机械、电学、热学、磁学、光学、腐蚀性.3.除了结构与性质,材料科学与工程还有其他两个重要的组成部分,即加工与性能.4.工程师或科学家越熟悉材料的各种性质、结构、性能之间的关系以与材料的加工技术,根据以上的原则,他或她就会越自信与熟练地对材料进行更明智的选择.5.只有在少数情况下,材料才具有最优或最理想的综合性质.因此,有时候有必要为某一性质而牺牲另一性能.6.Interdisciplinary dielectric constantSolid material<s> heat capacityMechanical property electromagnetic radiationMaterial processing elastic modulus7.It was not until relatively recent times that scientists came to understand the relationships between the structural elements of materials and their properties.8. Materials engineering is to solve the problem during the manufacturing and application of materials.9.10.Mechanical properties relate deformation to an applied load or force.Unit 21.金属是电和热很好的导体,在可见光下不透明；擦亮的金属表面有金属光泽.2.陶瓷是典型的导热导电的绝缘体,并且比金属和聚合物具有更高的耐热温度和耐恶劣环境性能.3.用于高科技领域的材料有时也被称为先进材料.4.压电陶瓷在电场作用下膨胀和收缩；反之,当它们膨胀和收缩时,他们也能产生一个电场.5.随着能够观察单个原子或者分子的扫描探针显微镜的出现,操控和移动原子和分子以形成新结构成为可能,因此,我们能通过一些简单的原子水平的构建就可以设计出新的材料.6.advanced materials ceramic materialshigh-performance materials clay mineralsalloy implantglass fibre carbon nanotube7.Metallic materials have large numbers of nonlocalized electrons and many properties of metals are directlyattributable to these electrons.8.Many of polymeric materials are organic compounds with very large molecular structures.9.Semiconductors hace electrical properties that are intermediate between the electrical conductors<viz. metalsand metal alloys> and insulators<viz. ceramics and polymers>.10.Biomaterials must not produce toxic substances and must be compatible with body tissues.Unit 31．金属的行为〔性质〕不同于陶瓷的行为〔性质〕,陶瓷的行为〔性质〕不同于聚合物的行为〔性质〕. 2．原子结构主要影响化学性质、物理性质、热学性质、电学性能、磁性能、光学性能.微结构和宏观结构虽也能影响这些性能但是他们主要影响力学性能和化学反应速率.3．金属的强度表明原子是通过强的键结合在一起的.4．元素的原子序数表明该元素的原子核内带正电的质子数.而原子的原子量则表明该原子核中质子数与中子数.5．Microstructure macrostructureChemical reaction atomic weightBalanced electrical charge positively charged proton6. 100 atoms form thousands of different substances ranging from the air we breathe to the metal used to supporttall buildings,7．The facts suggests that metallic atoms are held together bu strong bonds.8. Microstructure which includes features that cannot be seen with the naked eye,but using a microscope.Macrostructure includes features that can be seen with the naked eye.9. The atomic weight is the sum of proton number and neutron number in the nucleus.Unit 41．当密度小于水的密度时,物体将漂浮在水面上,当密度大于水的密度时,物体会沉降.相似的,当比重小于1时,物体将漂浮在水面上,当比重大于1时,物体会沉降.2．由于相互排斥而往相反的方向移动,导致磁通量密度比真空中小,这种材料为反磁性材料.3．使磁通量密度提高1倍以上小于或等于10倍的材料叫顺磁性材料,使磁通量密度提高10倍以上的材料叫铁磁性材料.4．某些铁磁性材料,特别是一些粉末状或夹层铁,钢或镍合金的相对导磁率可高达1000000.反磁性材料的相对导磁率小于1,但是到目前还没有哪种材料的相对导磁率远小于1.5．当顺磁性或铁磁性的芯插入线圈时,其磁感应系数等于相对磁导率乘以空芯时的磁感应系数. 6．specific gravity boiling point magnetic inductioncoefficient of thermal conductivity glass transition temperaturenon-ferrous metals linear coefficient of thermal expansionmass per unit of volume7. Properties that describe how a substance changes into a completely different substance are called chemicalproperties.8. Phase is a physical property of matter and matter can exist in four phases: solid, liquid, gas and plasma.9. At some temperature below the melting point, polymers start to lose their crystalline structure but the moleculesremain linked in chains, which tesults in a soft and pliable material.10. In engineering applications, permeability is often expressed in relative, rather than in absolute.Unit 51. 金属的力学性能决定了材料的使用X围与期望的服役寿命.2. 因此,一般多测几次以得到力学性能,报导的数值一般是平均值或者计算的统计最小值.3．材料的承载方式极大地影响了材料的力学性能,也决定了材料失效形式,以与在失效前是否有预警. 4．然而,受力弯曲时会产生一个应力分布,应力大小与到轴线的垂直距离有关.5．材料受到低于临界压力即屈服强度的力时,材料才会发生弹性形变.6．Test specimen static loading force normal axisEngineering strain critical stress yield strength stress areaStress- strain curve7. Temperatures below room temperature generally cause an increase in strength properties of metallic alloys;while ductility, fracture toughness, and elongation usually decrease.8. From the respective of what is happening within a material, stress is the internal distribution of forces withina body that balance and react to the loads applied to it.9. Engineering strain is defined as the amount of deformation in the direction of the applied force divided bythe initial length of the material.10. A material with high strength and high ductility will hace more toughness than a material with low strengthand high ductility.Unit 61. 随着影响我们星球上人类生存条件的社会问题的即将出现,材料科学与工程界有责任和机遇通过解决未来世界的需求—在能量、交通、住房、饮食、回收和健康方面的需求来改变世界.2. 不发达国家的人口增长率远高于1.4%的世界平均人口增长率.3. 全球能源使用的预算在2025以前将以每年1.7%速度增长,这比世界人口增长率快多了.4. 此外,发达地区的人均能量使用量是不发达地区人均能量使用量的九倍以上.5. gross domestic product materials science and engineering market economySocietal issues economic index sanitationGross national product popilation growth rate6. Some things that have been constant over time are human innovation and creativity, the engineer’s ability toaddress societal needs, and the entrepreneurial spirit of engineering.7. We have witnessed the re-shaping of our lives through revolutions that hace taken place in medicine,telecommunications, and transportantion industries.8. Eighteen percent of the world’s population lacks access to safe drinking water and nearly 40% has no access tosanitation.9. Materials and society are interlinked, and it is only rational that we should see a close relation between the MSEresearch agenda and societal issues that affect the human condition on the globe.Unit 71.从化学角度来说,金属是一类容易失电子以形成正离子的元素,它与其他金属原子形成金属键.2.金属键的无方向性被认为是金属具有延展性的主要原因.3.存在着共价键的晶体只有在原子之间的键断裂的情况下变形,从而导致晶体破裂.4.合金特别是为满足更高应用要求的合金比如喷气发动机,可能含有十种以上的元素.5.delocalized electron electronic structurealkaline earth metal chemical cellnuclear charge electric conductivity6.Metals are sometimes described as a lattice of positive ions surrounded by a cloud of delocalized electrons.7.Metals in general have superior electric and thermal conductivity, high luster and density, and the ability to bedeformed under stress without cleaving.8.An alloy is a mixture of two or more elements in solid solution in which the major component is a metal.bining different ration of metals as alloys modifies the properties of pure metals to produce desirablecharacteristics.Unit 81.超耐热合金的发展非常依赖于化学与加工的创新,并主要受到航空和能源工业的推动.2.抗蠕变性能主要取决于晶体结构内位错速度的放缓.3.超耐热合金在加工方面的发展使超耐热合金的操作温度大幅度提高.4.单晶高温合金是运用改进的定向凝固技术而形成单晶的,因此在材料中并无晶界.5.faced-centred cubic crystal structure turbine entry temperaturemetallic materials phase stabilitynuclear reactor synthesis of nanoparticle6.Superalloys typically hace an sustenitic faced-centered cubic crystal structure.7.Superalloys are used where there is a need for high temperature strength and corrosion/oxidation resistance.8.Superalloys are widely used in aircraft ,submarines, nuclear reactors and military electric motors.9.At high temperatures the gaseous aluminum chloride<or fluoride> is transfereed to the surface of part anddiffuseds inside.Unit 91.腐蚀过程从本质上说是一个电化学的过程,有着与电池相同的本质特征.2. 从矿物中提炼金属所需能源的问题与后续的腐蚀和能量释放直接相关.3. 当电子与中和的正离子〔如电解液中的氢离子〕发生反应时,阴极处电子得以平衡.4．Protective film circuitFree electron electron transferMetal cation anode reaction5.Some metals, such as gold and silver, can be found in the earth in their natural, metallic state, and they havelittle tendency to corrode.6.Oxidation is the process of stripping electrons from an atom and reduction occurs when an electron is addedto an atom.7.If the surface becomes wet, corrosion may take place through ionic exchange in the surface water layerbetween the anode and cathode.8.Corrosion is commonly classification based on the appearance of the corroded material.Unit 101. 我们要观察〔研究〕这些性能,看它们与我们所期望的陶瓷的组成有多匹配.2. 在高于玻璃化转变温度的高温下,玻璃不再具有脆性行为,而表现为粘稠液体.3. 它们显示出优异的力学性能、抗腐蚀/氧化性能,或电学、光学抑或是磁学性能.4. 一般认为,先进是最近100年才发展起来的,而传统的基于粘土的陶瓷早已在25000多年前就被使用了.5. the glass transition temperature ionic-covalent bondStress distribution coefficient of thermal expansionGlass optical fibre materials science and engineeringSolid-oxide fuel cells electron microscopy6. Diamond, which is classified as a ceramic, has the highest thermal conductivity of any known material.7. Ceramic are stronger in compression than in tension, whereas metals have comparable tensile and compressivestrength.8. Ceramics generally have low toughness, although combining them in composites can dramatically improvethis property.9. The functions of ceramic products are dependent on their chemical composition and microstructure, whichdetermines their properties.Unit 111. 材料科学与工程领域经常是根据四大方面—合成与加工,结构与组成,性质与性能之间的相互联系来定义的.2．我们不仅要考虑具有完美晶格和理想结构〔的情况〕,我们也要考虑材料中不可避免的结构缺陷的存在,甚至是无定形的.3. 通过热压可使孔径减小从而得到高密度产品.4. 在运输时,厂方要提供关于产品危害方面的信息.5. crystalline ceramics grain boundaryAlkaline earth oxide oxide additiveTriple point saturation magnetizationTelevision tube the color scale6.To understand the behavior and properties of any material, it is essential to understand its structure.7.The grain size is determined by the size of the initial powder particles and the way in which they wereconsolidated.8.Transparent or translucent ceramics require that we limit the scattering of light by pores and second-phaseparticles.9.Alumina ceramics are used as electrical insulators because of theie high electrical resistivity and lowdielectric constant.Unit 121. 材料的选择是任何组分设计至关重要的环节,尤其在植入体和其它医疗器械方面是特别重要的.2. 我们能进行承载应用的三种主要材料是金属、聚合物和陶瓷.3. 高密度、高纯度的氧化铝被大量的用于植入物,特别是在需要承载压力的髋关节修复和牙移植中.4. 在陶瓷或陶瓷复合材料中,氧化锆的磨损率远远高于氧化锆铝的磨损率.5. controlled reaction stress shieldingTotal hip prosthese strain-to-failure ratioMechanical stress flexural strengthMartensitic transformation6.Biomaterial is a non-viable material used in a medical device intended to interact with biological systems.7.These repairs become necessary when the existing part becomes diseased, damaged, or just simply wears out.8.Because of its low density, cancellous bone has a lower E and higher strain-to-failure ratio than cortical bone.9.Eliminating stress shielding, by reducing E, is one of the primary motivations for the development ofbioceramic composites.10.There are questions concerning the long-term effect of radiation emission from zirconia ceramics.Unit 131. 聚合物的俗名叫塑料,这个词指的是一大类具有许多性质和用途的天然材料和合成材料.2. 聚合物合成是一个把叫做单体的小分子通过共价键的结合形成链的过程.3. 支化聚合物分子是由一条带有一个或多个侧基或支链的主链组成.一些特殊的支化聚合物有星型聚合物、梳状聚合物和刷状聚合物.4. 某些生物聚合物是由一系列不同的胆识结构却相关的单体组成的,例如聚核苷酸是由核苷组成的.5. persistence length cross-linkPolar monomer nucleic acidPolymerization polyelectrolyte6.Most commercially important polymers today are entirely synthetic and produced in high volume, onappropriately scaled organic synthetic techniques.7.Some biological polymers are composed of a variety of different but structurally related monomers, suchas polynucleotides composed of nucleotide sbunits.8. A polymer molecule with a high degree of crosslinking is referred to as a polymer network.9.In polymers, however, the molecular mass may be expressed in terms of degree of polymerization,essentially the number of monomer Units which comprise the polymer.Unit 141. 大量合成的聚合物具有碳-碳骨架,这是因为碳原子具有与其它原子形成更强更稳定的键的优异性能.2. 它们在一定X围内软化,这与完好晶体相具有非常明确的熔点不同.3. 分子量取决于其合成时的条件,因此分子量可能分布很宽或分布很窄.4. Goodyear 很偶然的发现了在橡胶中加入硫磺并加热这个混合物能使橡胶变硬,对氧化和化学进攻能力的敏感性降低.5. thermosetting plastic cross-sectional areaPolymerization reaction double bondChemical composition carboxylic acidMelting point degradation by oxidation6.Polymer with different chemical composition has different physical and chemical property.7. A thermosetting plastic is shaped through irreversible chemical processes and therefore cannot be reshapedreadily.8.Natural rubber is not a useful polymer because it is too soft and too chemically reactive.9.Various substances may be added to polymers to provide protection against the effects of sunlight or againstdegradation by oxidation.Unit 151. 逐渐增强的环境意识促使包装薄膜与其加工既要方便使用又要具有环境友好的特点.2. 显而易见,实现这些性能对控制和改进机械性能和阻隔性能是非常重要的.3. 在羧酸、醇、醛、酮的含氧生物降解过程中,由水和热引发的过氧化反应可以使之降解成低摩尔质量的物质,这就是碳氢聚合物力学性能降低的主要原因.4. 用持久耐用的聚合物做短期使用的包装材料并不合理,另外也是因为包装材料被食物污染后再进行物理回收是不切合实际的.5. natural gas packaging materialsAroma compound bioplastic materialChemical structure the life cycle of biomass6. Bacteria , fungi, enzymes start the bioassimilation giving rise to biomass and CO2 that finally form the humus.7. The bioplastic aim is to imitate the life cycle of biomass, which includes conservation of fossil resources, waterand CO2 production.8. During the oxo-degradation of carboxylic acid, molecules of alcohols, aldehydes and ketones degradable withlow molar mass are produced by peroxidation initiated by heat or light .9. While most of the commercialized biopolymer materials are biodegradable, these are not fully compostable inreal composting conditions, which vary with temperature and relative humidity.Unit 161. 比如,多相金属在微观尺度上是复合材料.但一般意义上的复合材料是指通过键的作用使两种或多种不同的材料结合在一起的材料..2. 最常见的是,复合材料有一个连续的叫基体的本体相,还有一个分散的非连续的叫增强相的相.3. 先进材料采用了树脂与纤维的复合材料,一般为碳/石墨,凯芙拉或玻璃纤维与环氧树脂的复合材料.纤维具有高的硬度,而聚合物树脂基体能保持复合材料的结构.4. 如果复合材料设计和制备合理的话,复合材料就既具有增强相的强度又具有基体的韧性从而得到了性能的理想组合,这是任何一种组分单独存在时所具备的性能.5. composite material reinforcement materialFiberglass matrix materialStrengthening mechanism conventional material6. A composite is commonly defined as a combination of two or more distinct materials, each of which retainsits own distinctive properties, to create a new material with properties that cannot be achieved by any of the components acting alone.7.Carbon-epoxy composties are two thirds the weight of aluminum, and two and a half times as stiff.Composites are resistant to fatigue damage and harsh enviroments, and are repairable.8.According to the conception of composite , reinforced plastics, metal-matrix composites, ceramic-matrixcomposites and concrete are composites.9.In fiber-reinforced composites, the fiber is the primary load-bearing component. Fiberglass and carbon fibercomposites are examples of fiber-reinforced composites.Unit 171. 震荡、撞击或者重复的周期性应力能导致两层的界面处发生薄层分离,这种情况叫剥离.2.3. 事实上,工业材料既要质轻又要牢固的要求是推动复合材料发展的主要动力.4. 提到飞机,值得铭记的是复合材料不像金属〔如铝〕那样在压力的作用下会完全解体.5. orthotropic thermosetThermoplastic Young’s ModulusMechanical property constants extreme enviroment6.In contrast, isotropic material < for example, aluminuim or steel>, in standard wrought forms, typicallyhave the same stiffness regardless of the directional orientation of the applied forces and /or moments.7.The greatest advantage of composite materials is strength and stiffness combined with lightness.8.This makes them ideal for use in products thar are exposed to extreme enviroments such as boats,chemical-handling equipments and spacecrafts.posites will never totally replace tranditional materials like steel, but in many cased they are just whatwe need.Unit 181. 具有相分离的聚合物共混材料经常出现纳米尺度的相.2 在过去几十年里研究的基于溶胶-凝胶化学的有机-无机纳米复合材料已基本淡出纳米复合材料的研究.3. 理解粒子的性质随着尺寸降低到纳米级别而发生改变,这对于优化所得到的纳米复合材料很重要.4. 廉价石墨的生产尚未实现,石墨的广泛使用呕待石墨合成技术的突破.5. electro-optical property bactericidal propertyBlock copolymer interfacial phenomenaExfoliated graphene morphology control6.The field of nanotechnology is one of the most popular areas for current research and development inbasically all technical discillines.7.Nanoscale is considered where the dimensions of the particle, platelet or fiber modification are in the rangeof 1～100nm.8.These improvements are key to future aircraft and wind energy turbine applications.9.Nanostructured surfaces have been noted to yield superhydrophobic character and exceptional adhesion.。
化学化工专业英语电子版课本
ContentPART 1 Introduction to Materials Science ＆Engineering 1 Unit 1 Materials Science and Engineering 1 Unit 2 Classification of Materials 9 Unit 3 Properties of Materials 17 Unit 4 Materials Science and Engineering: What does the Future Hold? 25 Part ⅡMETALLIC MATERLALS AND ALLOYS33 Unit 5 An Introduction to Metallic Materials 33 Unit 6 Metal Manufacturing Methods 47 Unit 7 Structure of Metallic Materials 57 Unit 8 Metal-Matrix Composites 68 Part ⅢCeramics 81 Unit 9 Introduction to Ceramics 81 Unit 10 Ceramic Structures —Crystalline and Noncrystalline 88 Unit 11 Ceramic Processing Methods 97 Unit 12 Advanced ceramic materials –Functional Ceramics 105 PARTⅣNANOMATERIALS 112 Unit 13 Introduction to Nanostructured Materials 112 Unit14 Preparation of Nanomaterials 117 Unit 15 Recent Scientific Advances 126 Unit 16 The Future of Nanostructure Science and Technology 130 Part ⅤPOLYMERS 136Unit17 A Brief Review in the Development of Synthetic Polymers 136 Unit18 Polymer synthesis: Polyethylene synthesis 146 Unit19 Polymer synthesis: Nylon synthesis 154 Unit 20 Processing and Properties Polymer Materials 165 PART VI POLYMERIC COMPOSITES 172 Unit21 Introduction to Polymeric Composite Materials 172 Unit22 Composition, Structure and Morphology of Polymeric Composites 178 Unit23 Manufacture of Polymer Composites 185 Unit24 Epoxy Resin Composites 191 Part 7 Biomaterial 196 Unit 25 Introduction to Biomaterials 196 Unit 26 Biocompatibility 205 Unit 27 Polymers as Biomaterials 213 Unit 28 Future of Biomaterials 224 PARTⅧMaterials and Environment 237 Unit29 Environmental Pollution & Control Related Materials 237 Unit30 Bio-degradable Polymer Materials 241 Unit 31 Environmental Friendly Inorganic Materials 248 Unit 32 A Perspective on the Future: Challenges and Opportunities 256 附录一科技英语构词法263 附录二科技英语语法及翻译简介269附录三：聚合物英缩写、全名、中文名对照表280附录四：练习题参考答案284PART 1 Introduction to Materials Science ＆EngineeringUnit 1Materials Science and EngineeringHistorical PerspectiveMaterials are probably more deep-seated in our culture than most of usrealize. Transportation, housing, clothing, communication, recreation, and food production —virtually every segment of our everyday lives is influenced to one degree or another by materials. Historically, the development and advancement of societies have been intimately tied to the members’ ability to produce and manipulate materi- als to fill their needs. In fact, early deep-seated根深蒂固的, 深层的civilizations have been designated by the level of their materials development (Stone Age, Bronze Age, Iron Age).The earliest humans had access to only a very limited number of materials, those that occur naturally: stone, wood, clay, skins, and so on. With time they discovered techniques for producing materials that had propertiessuperior to those of the natural ones; these new materials included pottery and various metals. Furthermore, it was discovered that the properties of a material could be altered by heat treatments and by the addition of other substances. At this point, materials utilization was totally a selection process that involved deciding from a given, rather limited set of materials the one best suited for an application by virtue of its characteristics.①It was not until relatively recent times that scientists came to understand the relationships between the structural elements of materials and their properties. This knowledge, acquired over approximately the past 100 years, has empowered them to fashion, to a large degree, the characteristics of materials. Thus, tens of thousands of different materials have evolved with rather specialized charac- teristics that meet the needs of our modern and complex society; these include metals, plastics, glasses, and fibers.The development of many technologies that make our existence so comfortable has been intimately associated with the accessibility of suitable materials. An advancement in the understanding of a material type is often the forerunner to the stepwise progression of a technology. For example, pottery // 陶器structural elements结构成分；property //.性能automobiles would not have been possibl- e without the availability of inexpensive steel or some other comparable substitute. In our contemporary era, sophisticated electronic devices rely on components that are made from what are called semiconducting materials.Materials Science and EngineeringThe discipline of materials science involves investigating the relationships that exist between the structures and properties of materials. In contrast, materials engineering is, on the basis of these structure–property correlations, designing or engineering the structure of a material to produce a predetermined set of properties.“Structure’’is at this point a nebulous term that deserves some explanation. In brief, the structure of a material usually relates to the arrangement of its internal components. Subatomic structure involves electrons within the individual atoms and interactions with their nuclei. On an atomic level, structure encompasses the organization of atoms or molecules relative to one another. The next larger structural realm, which contains large groups of atoms that are normally agglomerated together, is termed ‘‘microscopic,’’meaning that which is subject to direct observation using some type of microscope. Finally, structural elements that may be viewed with the naked eye are termed ‘‘macroscopic.’’The notion of ‘‘property’’ deserves elaboration. While in service use, all materials are exposed to external stimuli that evoke some type of response. stepwise//逐步的sophisticated//精制的，复杂的；semiconducting materials 半导体材料nebulous//含糊的，有歧义的subatomic//亚原子的microscopic//For example, a specimen subjected to forces will experience deformation; or a polished metal surface will reflect light. Property is a material trait in terms of the kind and magnitude of response to a specific imposed stimulus. Generally, definitions of properties are made independent of material shape and size.Virtually all important properties of solid materials may be grouped into six different categories: mechanical, electrical, thermal, magnetic, optical, and deteriorative. For each there is a characteristic type of stimulus capable of provoking different responses. Mechanical properties relate deformation to an applied load or force; examples include elastic modulus and strength. For electrical properties, such as electrical conductivity and dielectric constant, the stimulus is an electric field. The thermal behavior of solids can be represented in terms of heat capacity and thermal conductivity. Magnetic properties demonstrate the response of a material to the application of a magnetic field. For optical properties, the stimulus is electro- magnetic or light radiation; index of refraction and reflectivity are representative optical properties. Finally, deteriorative characteristics indicate the chemical reactivity of materials.In addition to structure and properties, two other important components are involved in the science and engineering of materials, viz. ‘‘processing’’and ‘‘performance.’’With regard to the relationships of these four components, the structure of a material will depend on how it is processed. 微观的// 宏观的deformation// 变形deteriorative//破坏（老化的）elastic modulus 弹性模量strength //强度；dielectric constant介电常数；heat capacity 热容量refraction。
科技英语译文
UNIT 1 日本人的赶时髦风鲍勃约翰斯顿对日本人生活习惯的观察[1]不久前，我到东京去修理MODEM，那个MODEM是个小盒子，我用它把文章通过电话线送到伦敦。
约在一年前我买这个MODEM 时惊奇地注意到它的产地是台湾，而不是日本。
当时，因为把日文手稿键入计算机的困难，使得通过MODEM来通信还不普及。
所以没有一家大的日本电子公司能生产出便宜的MODEM，如果考虑到日本人什么都能制造的话，这不能不说是个大的缺憾。
[2]我向商店的店员打听，他们是否还从台湾进口MODEM，不了，他向我保证现在所有的MODEM都是地产货，而我用的MODEM，只能以300“波特”（每秒比特）来传送，再也买不到了。
现在的替代产品速度更快，可达1200波特。
店员还告诉我，不久又会有2400波特的换代产品。
我问他对于个人用户来说是否有必要传送得那么快，他承认确实没必要，只是解释“这是日本人的方式，一旦出现比已有的更好的新产品，他们就要换新的，不管真的需要不需要。
”[3]那个星期的晚些时候，在一个完全不同，意想不到的场合，我又碰到了说明日本人的此种癖好的另一个例子。
我就日本刚建成的目前世界最大功率的粒子加速器一事，采访了东京大学的一名物理学教授。
他告诉我，他的同事们已经为这台新机器烦恼了，他们抱怨这台加速器太小了，因此提议放弃它，并支持建造更大，功率更强的加速器的计划。
而这一切发生在这台新加速器还来不及进行一次粒子碰撞的时候！这位教授，在美国生活多年，使得他与通常的日本学者相比明显地坦诚，他认为，“在日本，这是很典型的：我们设计和制造的东西总被每个人认为是过时的。
”[4]这两件事情让我不禁思考为什么日本人看起来总是不满意他们已有的东西，为什么他们总有一股冲动想跑出去买下每件最新的东西。
这是不是日用电子公司不休止的价格战导致了日本人的巴普洛夫条件反射，每当他们看到一则广告，忍受那句有魔力的语言“shin hatsu bali”——新上市时，总是不由自主地自动掏腰包（更多掏的是女用钱包，因为在日本，妻子通常负责家庭的开销）。
化学化工专业英语电子版课本.
ContentPART 1 Introduction to Materials Science &Engineering 1 Unit 1 Materials Science and Engineering 1 Unit 2 Classification of Materials 9 Unit 3 Properties of Materials 17 Unit 4 Materials Science and Engineering: What does the Future Hold? 25 PartⅡMETALLIC MATERLALS AND ALLOYS 33 Unit 5 An Introduction to Metallic Materials 33 Unit 6 Metal Manufacturing Methods 47 Unit 7 Structure of Metallic Materials 57 Unit 8 Metal-Matrix Composites 68 PartⅢCeramics 81 Unit 9 Introduction to Ceramics 81 Unit 10 Ceramic Structures —Crystalline and Noncrystalline 88 Unit 11 Ceramic Processing Methods 97 Unit 12 Advanced ceramic materials –Functional Ceramics 105 PARTⅣNANOMATERIALS 112 Unit 13 Introduction to Nanostructured Materials 112 Unit14 Preparation of Nanomaterials 117 Unit 15 Recent Scientific Advances 126 Unit 16 The Future of Nanostructure Science and Technology 130 PartⅤPOLYMERS 136 Unit17 A Brief Review in the Development of Synthetic Polymers 136 Unit18 Polymer synthesis: Polyethylene synthesis 146 Unit19 Polymer synthesis:Nylon synthesis 154 Unit 20 Processing and Properties Polymer Materials 165 PART VI POLYMERIC COMPOSITES 172 Unit21 Introduction to Polymeric Composite Materials 172 Unit22 Composition, Structure and Morphology of Polymeric Composites 178Unit23 Manufacture of Polymer Composites 185 Unit24 Epoxy Resin Composites 191 Part 7 Biomaterial 196 Unit 25 Introduction to Biomaterials 196 Unit 26 Biocompatibility 205 Unit 27 Polymers as Biomaterials 213 Unit 28 Future of Biomaterials 224 PARTⅧMaterials and Environment 237 Unit29 Environmental Pollution & Control Related Materials 237 Unit30 Bio-degradable Polymer Materials 241 Unit 31 Environmental Friendly Inorganic Materials 248 Unit 32 A Perspective on the Future: Challenges and Opportunities 256 附录一科技英语构词法263 附录二科技英语语法及翻译简介269附录三:聚合物英缩写、全名、中文名对照表280 附录四:练习题参考答案284 PART 1 Introduction to Materials Science &EngineeringUnit 1Materials Science and Engineering Historical PerspectiveMaterials are probably more deep-seated in our culture than most of us realize. Transportation, housing, clothing, communication, recreation, and food production —virtually every segment of our everyday lives is influenced to one degree or another by materials. Historically, the development and advancement of societies ha ve been intimately tied to the members‘ ability to produce and manipulate materi- als to fill their needs. In fact, early civilizations have been designated by the level of their materials development (Stone Age, Bronze Age, Iron Age.The earliest humans had access to only a very limited number of materials, those that occur naturally: stone, wood, clay, skins, and so on. With time they discovered techniques for producing materials that had properties superior to those of the natural ones; these new materials included pottery and various metals. Furthermore, it was discovered that the properties of a material could be altered by heat treatments and by the addition of other substances. At this point, materials utilization was totally a selection process that involved deciding from a given, rather limited set of materials the one best suited for an application by virtue of its characteristics.①It was not until relatively recent times that scientists came to understand the relationships between the structural elements of materials and their properties. This knowledge, acquired over approximately the past 100 years, has empowered them to fashion, to a large degree, the characteristics of materials. Thus, tens of thousands of different materials have evolved with rather specialized charac- teristics that meet the needs of our modern and complex society; these include metals, plastics, glasses, and fibers. deep-seated根深蒂固的, 深层的pottery / ☐☯❑♓陶器structural elements结构成分;property / ☐❑☐☜♦♓/⏹.性能The development of many technologies that make our existence so comfortable has been intimately associated with the accessibility of suitable materials. An advancement in the understanding of a material type is often the forerunner to the stepwise progression of a technology. For example, automobiles would not havebeen possibl- e without the availability of inexpensive steel or some other comparable substitute. In our contemporary era, sophisticated electronic devices rely on components that are made from what are called semiconducting materials. Materials Science and EngineeringThe discipline of materials science involves investigating the relationships that exist between the structures and properties of materials. In contrast, materials engineering is, on the basis of these structure–property correlations, designing or engineering the structure of a material to produce a predetermined set of properties.―Structure‘‘ is at this point a nebulous term that deserves some explanation. In brief, the structure of a material usually relates to the arrangement of its internal components. Subatomic structure involves electrons within the individual atoms and interactions with their nuclei. On an atomic level, structure encompasses the organization of atoms or molecules relative to one another. The next larger structural realm, which contains large groups of atoms that are normally agglomerated together, is termed‗‗microscopic,‘‘ meaning that which is subject to direct observation using some type of microscope. Finally, structural elements that may be viewed with the naked eye are termed ‗‗macroscopic.‘‘The notion of ‗‗property‘‘ deserves elaboration. While in service use, all materials are exposed to external stimuli that evoke some type of response. For example, aspecimen subjected to forces will experience deformation; or a polished metal surface will reflect light. Property is a material trait in terms of the kind and magnitude of response to a specific imposed stimulus. Generally, definitions of properties are made independent of material shape and size.Virtually all important properties of solid materials may be grouped into six different categories: mechanical, electrical, thermal, magnetic, optical, and stepwise /♦♦♏☐♦♋♓/ ♎逐步的sophisticated/♦☯♐♓♦♦♓♏♓♦♓♎/ ♎精制的,复杂的; semiconducting materials 半导体材料nebulous/ ⏹♏♌✞●☯♦/♎含糊的,有歧义的subatomic/ ♦✈♌☯❍♎亚原子的microscopic/❍♓❑☯☐♓♎微观的❍♋♍❑☐♦♍☐☐♓♍/❍✌❑☯✞☐♓♎宏观的deteriorative. For each there is a characteristic type of stimulus capable of provokingdifferent responses. Mechanical properties relate deformation to an applied load or force; examples include elastic modulus and strength. For electrical properties, such as electrical conductivity and dielectric constant, the stimulus is an electric field. The thermal behavior of solids can be represented in terms of heat capacity and thermalconductivity. Magnetic properties demonstrate the response of a material to the application of a magnetic field. For optical properties, the stimulus is electro- magnetic or light radiation; index of refraction and reflectivity are representative optical properties. Finally, deteriorative characteristics indicate the chemical reactivity of materials.In addition to structure and properties, two other important components are involved in the science and engineering of materials, viz. ‗‗processing‘‘ and‗‗performance.‘‘ With regard to the relationships of these four components, the structure of a material will depend on how it is processed. Furthermore, a material‘s perf ormance will be a function of its properties.Fig. 1.1 Photograph showing the light transmittance of three aluminum oxide specimens. From left to right: single crystal material (sapphire, which is transparent;a polycrystalline and fully dense (nonporous material, which is translucent; and a polycrystalline material that contains approximately 5% porosity, which is opaque. (Specimen preparation, P. A. Lessing; photography by J. Telford.We now present an example of these processing-structure-properties-perfor- mance principles with Figure 1.1, a photograph showing three thin disk specimens placed over some printed matter. It is obvious that the optical properties (i.e., the deformation/♎♓♐❍♏♓☞☯变形deteriorative/♎♓♓☯❑♓☯❑♏♓♦♓破坏(老化的elastic modulus 弹性模量strength /♦♦❑♏⏹♑强度;dielectric constant介电常数;heat capacity 热容量refraction/❑♓♐❑✌☞☯折射率; reflectivity/ ❑♓♐●♏♓♓♦♓/ 反射率processing/☐❑☯◆♏♦♓☠加工light transmittance of each of the three materials are different; the one on the left is transparent (i.e., virtually all of the reflected light passes through it, whereas the disks in the center and on the right are, respectively, translucent and opaque.All of these specimens are of the same material, aluminum oxide, but the leftmost one is what we call a single crystal—that is, it is highly perfect—which gives rise to its transparency. The center one is composed of numerous and verysmall single crystals that are all connected; the boundaries between these small crystals scatter a portion of the light reflected from the printed page, which makes this material optically translucent.②And finally, the specimen on the right is composed not only of many small, interconnected crystals, but also of a large number of very small pores or void spaces. These pores also effectively scatter the reflected light and render this material opaque.Thus, the structures of these three specimens are different in terms of crystal boundaries and pores, which affect the optical transmittance properties. Furthermore, each material was produced using a different processing technique. And, of course, if optical transmittance is an important parameter relative to the ultimate in-service application, the performance of each material will be different.Why Study Materials science and Engineering?Why do we study materials? Many an applied scientist or engineer, whether mechanical, civil, chemical, or electrical, will at one time or another be exposed to a design problem involving materials. Examples might include a transmission gear, the superstructure for a building, an oil refinery component, or an integrated circuit chip. Ofcourse, materials scientists and engineers are specialists who are totally involved in the investigation and design of materials.Many times, a materials problem is one of selecting the right material from the many thousands that are available. There are several criteria on which the final decision is normally based. First of all, the in-service conditions must be charac- terized, for these will dictate the properties required of the material. On only rare occasions does a material possess the maximum or ideal combination of properties. transmittance/♦❑✌❍♓♦☜⏹♦/ ⏹. 透射性sapphire /♦✌♐♓☯蓝宝石transparent/♦❑✌☐☪☯❑☯⏹♦/ ♎透明的;polycrystalline/ ☐♓❑♓♦♦☯♓多晶体; translucent/♦❑✌✞♎半透明的; opaque☯✞☐♏♓♎不透明的single crystal 单晶体Thus, it may be necessary to trade off one characteristic for another. The classic example involves strength and ductility; normally, a material having a high strength will have only a limited ductility. In such cases a reasonable compromise between two or more properties may be necessary.A second selection consideration is any deterioration of material properties that may occur during service operation. For example, significant reductions in mecha- nical strength may result from exposure to elevated temperatures or corrosive envir- onments.Finally, probably the overriding consideration is that of economics: What will the finished product cost? A material may be found that has the ideal set of proper- ties but is prohibitively expensive. Here again, some compromise is inevitable.The cost of a finished piece also includes any expense incurred during fabrication to produce the desired shape. The more familiar an engineer or scientist is with the various characteristics and structure–property relationships, as well as processing techniques of materials, the more proficient and confident he or she will be to make judicious materials choices based on these criteria.③Reference:William D. Callister, Materials science and engineering : anintroduction, Press:John Wiley & Sons, Inc.,2007;2-5 transmission gear传动齿轮dictate/♎♓♏♓决定trade off 权衡;折衷ductility♎✈♓●♓♦♓延展性/ ☯✞☯❑♋♓♎♓☠/♎最主要的judicious/♎✞✞♎♓☞☯♦/♎明智的Notes1.At this point, materials utilization was totally a selection process that involved deciding froma given, rather limited set of materials the one best suited for an application by virtue of itscharacteristics由此看来,材料的使用完全就是一个选择过程,且此过程又是根据材料的性质从许多的而不是非有限的材料中选择一种最适于某种用途的材料。
材料科学与工程_专业英语_Unit_2_Classification_of_Materials译文
Solid materials have been conveniently grouped into three basic classifications: metals, ceramics, and polymers. This scheme is based primarily on chemical makeup and atomic structure, and most materials fall into one distinct grouping or another, although there are some intermediates. In addition, there are three other groups of important engineering materials—composites, semiconductors, and biomaterials.译文：固体材料被便利的分为三个基本的类型：金属，陶瓷和聚合物。
这个分类是首先基于化学组成和原子结构来分的，大多数材料落在明显的一个类别里面，尽管有许多中间品。
除此之外，有三类其他重要的工程材料－复合材料，半导体材料和生物材料。
Composites consist of combinations of two or more different materials, whereas semiconductors are utilized because of their unusual electrical characteristics; biomaterials are implanted into the human body. A brief explanation of the material types and representative characteristics is offered next.译文：复合材料由两种或者两种以上不同的材料组成，然而半导体由于它们非同寻常的电学性质而得到使用；生物材料被移植进入人类的身体中。
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Part Ⅱ
polymers
Polysaccharides—多聚糖
淀粉（Starch） 菊糖（Lnulin） 树胶（Gums） 粘液（Mucilages） （多糖）由10个以上单糖分子缩合而 成，大多为无定形化合物，分子量较大， 水解后生成单糖或低聚糖
Part Ⅱ
polymers
Polypeptides —多肽
Part Ⅱ
polymers
Biological synthesis There are three main classes of biopolymers: polysaccharides,聚糖 polypeptides聚肽, and polynucleotides聚核苷酸. In living cells, they may be synthesized by enzyme-mediated processes, such as the formation of DNA catalyzed by DNA polymerase聚合酶.
Part Ⅱ
polymers
In 1922, Hermann Staudinger proposed that polymers consisted of long chains of atoms held together by covalent bonds, an idea which did not gain wide acceptance for over a decade and for which Staudinger was ultimately awarded the Nobel prize. Work by Wallace Carothers in the 1920s also demonstrated that polymers could be synthesized rationally from their constituent monomers.
Part Ⅱ
polymers
Synthetic polymer materials such as nylon尼龙, polyethylene, Teflon特富龙, and silicone 硅树脂 have formed the basis for a burgeoning polymer industry. These years have also shown significant developments in rational polymer synthesis. Most commercially important polymers today are entirely synthetic and produced in high volume on appropriately scaled organic synthetic techniques.
Part Ⅱ
polymers
Polymers are studied in the fields of polymer chemistry, polymer physics, and polymer science.
Part Ⅱ
polymers
Historical development
Starting in 1811, Henri Braconnot did pioneering work in derivative cellulose compounds, perhaps the earliest important work in polymer science. The development of vulcanization硫化 later in the nineteenth century improved the durability of the natural polymer rubber, signifying the first popularized semi-synthetic polymer.
Part Ⅱ
polymers
Typical Polymer
DNA
Part Ⅱ
polymers
Original text (P116~) While polymer in popular usage suggests plastic, the term of natural and synthetic materials with a wide variety of properties, including properties typically associated with plastics.
Part Ⅱ
polymers
Original text(P116)
A polymer is a large molecule (大分子 macromolecule) composed of repeating structural units结构单元 typically connected by covalent chemical bonds共价键. The word polymer is derived from the Greek words πολσ- - poly- meaning "many"; and μέρος - meros meaning "part".
Part Ⅱ
polymers
Polymer synthesis
Polymerization is the process of combining many small molecules小分子 known as monomers into a covalently bonded chain. During the polymerization process, some chemical groups may be lost from each monomer.. The distinct piece of each monomer that is incorporated into the polymer is known as a repeat unit 重复单元or monomer residue单体残基.
Part Ⅱ
polymers
Natural polymeric materials such as shellac虫胶, amber琥珀, and natural rubber天然橡胶 have been in use for centuries. Biopolymers 生物高分 子such as proteins蛋白质 and nucleic acids核酸 play crucial roles in biological processes. A variety of other natural polymers exist, such as cellulose纤维素, which is the main constituent of wood and paper.
是α－氨基酸以肽链连接在一起而形 成的化合物，它也是蛋白质水解的中 间产物。由20个以上的氨基酸残基组 成的肽。
Part Ⅱ
polymers
Polynucleotides —多核苷酸
RNA ----是遗传信息的 贮存和携带者
DNA ----参与遗传信 息表达的各过程
Part Ⅱ
polymers
The synthesis of proteins involves multiple enzymemediated processes to transcribe genetic information from the DNA to RNA and subsequently translate that information to synthesize the specified protein from amino acids氨基酸. The protein may be modified further following translation in order to provide appropriate structure and functioning.
Part Ⅱ
polymers
Unit 13
Part Ⅱ
polymers
Main line
1. What is the polymer?
2. Historical development 3. Polymer synthesis Laboratory synthesis Biological synthesis Modification of natural polymers 4. Polymer structure Monomer identity Chain linearity Chain length
Part Ⅱ
polymers
Laboratory synthesis Laboratory synthetic methods are generally divided into two categories, cnondensation polymerization缩合聚合 and addition polymerization 加成聚合 However, some newer methods such as plasma polymerization等离子体聚合 do not fit neatly into either category. Synthetic polymerization reactions may be carried out with or without a catalyst. Laboratory synthesis of biopolymers, especially of protein, is an area of intensive research.