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1、精選優(yōu)質(zhì)文檔-傾情為你奉上Lesson OneThe Development of RubberHere is a story about rubber.In the early part of the eighteen-hundreds, the Americans made use of natural for the first time. First they made overshoes to keep their feet dry. Then came a certain Mr. Mackintosh, who made coats of cloth covered with na
2、tural rubber. But these first rubber overshoes and raincoats were all soft and sticky in summer, and hard and unelastic in the winter when it was cold, the rubber we have today is not sticky but soft and elastic, though very strong-even in the warmest summer and the coldest winter. There would be no
3、 automobiles such as we have today without it. But at that time every attempt to make rubber hard and strong come to nothing. The early overshoes and raincoats were simply not good enough and their makers went out of business.Goodyear was living near some of these poor men and he got to work on this
4、 question of making rubber hard and strong. Once he started on this work, he was the sort of man who simply had to go on till he had overcome the trouble. First came the discovery that nitric acid (HNO3) made the rubber much better, and in a short time he was doing a small business in rubber shoes p
5、roduced in this way.Water, a friend of his had the idea that rubber might be made hard and strong if mixed with sulphur and put in the sun. Goodyear put his idea to the test , and saw that it did have more or less the desired effect, but only on the outside of the rubber. It is common knowledge now
6、that the way to make rubber hard and strong-to“vulcanize” it ,as we say , is by heating it with sulphur. Goodyear spent another four years, in which things went very hardly with him, before he made the discovery how to vulcanize rubber completely. When at last he did it, he had nothing left at all.
7、Everything of the smallest value had used to get money, even his childrens school-books.Almost every discovery or invention has come a sort of story behind it though they are not all quite such unhappy stories.New Words and Expressions1. made use of 使用,利用2. overshoe 套鞋(常用復(fù)數(shù))3. sticky 粘性的,(天氣)濕熱的4. e
8、lastic 彈性的,靈活的,有伸縮性的5. unelastic 沒有彈性的6. not.but 不是.而是.7. automobile rr (美語)汽車8. come to nothing 沒有結(jié)果,失敗9. simply 簡單地,真正地,樸素地10. out of business 停業(yè),歇業(yè)11. get to work on sth 開始做某事12. overcome 克服13. overcame, overcome14. nitric 含氮的15. acid (化學(xué))酸,酸的16. nitric acid 硝酸17. sulphur, sulfur (化學(xué))硫,硫磺18. put.
9、to the test 對進行試驗19. vulcanize 硫化20. at all 究意,全然,一點兒21. value 價值,評價22. school-books 教科書Lesson TwoThe Part by Rubber in Modern CivilizationRubber is indispensable to modern civilization. Its importance in every form of transport for tyres and tubes is self-evident and has been fully brought out. Abo
10、ut 80 per sent of all rubbers is used in the motor industry, mainly for tyres. This applies to passangers, goods transport, and private cars. Without rubber, the rarious form of transportation could not run, the communication system would break down.A large proportion of the remainder goes into what
11、 are known as mechanical goods, which include such articles as belting, packing, moulded good, hose and innumberable other tyres of products. Most of these articles are absolutely vital to the operation of the industry in general. Without them industry would come to a stand still.Rubber is of the gr
12、eatest possible importance in tyres on tractors for agricultural use. The change-over form steel wheels to pneumatlics has had a profound affect on agricultural development.The electrical industry is the large consumer. Rubber is of outstanding significance in the electrical industry as insulation,
13、particularly for eables. The reasons for its preeminent position are outstanding electrical properties, the good mechanical properties, and the ease with which it can be handled. Now Words and Expressions1. to play a part in 在方面起作用,對起作用2. modern 現(xiàn)代的,近代的,新式的3. civilization 文明,文化4. indispensable 絕對必要的
14、,不可缺少的5. transport 運輸6. tyre, tire 輪胎7. tube 管子,內(nèi)胎8. self-evident 自明的,不言而喻瓣9. bring out 說明,產(chǎn)生,顯出,發(fā)表,出版10. per cent 百分?jǐn)?shù)11. motor 發(fā)動機,電動機,馬達(dá)12. industry 工業(yè),產(chǎn)業(yè),刻苦13. mainly 主要地,大部分14. apply 應(yīng)用,申請15. passenger 乘客,旅客16. private 私人的,私有的,秘密的17. communication 通訊,傳播,交通18. system 系統(tǒng),體制,制度communication system
15、通訊系統(tǒng),交通體系19. proportion 比例20. remainder 剩余,余數(shù),剩下的人21. to be known as 通稱的,以著稱22. mechanical 機械的,力學(xué)的,工業(yè)的23. article 物品,文章24. belt 帶,膠帶25. pack 包,捆,堆,墊圈26. mould 模型27. hose 軟管,皮帶管28. inaumberable 無數(shù)的,數(shù)不清的29. absolutely 絕對地,完全地30. vital 生命的,非常的,有生命力的31. in general 總之,通常,一般說來32. come to a stand 停頓33. tra
16、ctor 拖拉機34. agricultural 農(nóng)業(yè)的35. change-over 調(diào)換,轉(zhuǎn)換36. wheel 車輪37. pneumatic 裝滿空氣的38. profound 深遠(yuǎn)的,很深的39. affect 影響40. electrical 電的41. consumer 消費者,消費品42. outstanding 顯著的,杰出的,未解決的43. significance 意義,重要性44. insulation 絕緣體45. cable 電纜46. pre-eminent 杰出的,卓越的47. property 財產(chǎn),性質(zhì)48. with ease with 輕易地Lesson
17、 ThreeNatural Rubber 、Synthetic Rubber and Reclaimed RubberNatural Rubber is a high molecular weight hydrocarbon which comes from the latex of many plants and is obtained by coagulation with chemicals, by drying, electrical coagulation and other processes. The most important producer is Hevea Brasil
18、iensis. The wild rubber produced form latex contains, besides the hydrocarbon, small quantities of protein, carbohydrates, resin-like substances, mineral salts and fatty acids. These other constituents act in part as natural accelerators and anti-oxidants and give the product processing properties w
19、hich do not exist in the pure hydrocarbon. Natural rubber is cis-1, 4-polyisoprene with the empirical formular (C5H8)nand the structural formular.CH3 CH2CCHCH2When vulcanized, rubber becomes highly extensible, shows fast recovery, and is highly elastic.“Synthetic rubber” is the common term, in fact
20、incorrect, for chemically different polymers with rubber-like properties. Since the term rubber applies to the original product, i.c. polyisoprene, the term synthetic rubber should strictly lerased only for synthetic “Natural Rubber”(cisl,4-polyisoprence). For polymers, with rubbery properties, whic
21、h do not have an identical structure to natural rubber, the terms artificial rubber, chemical rubber or synthesized rubber have been suggested. In modern usago the term rubber no longer refers to a chemically defined product but relates so physical properties, all synthetic polymers with properties
22、similar to those of natural rubber may therefore be classified as properties rubbers.In general, it may be stated tht synthetic rubber do not have all qualities of natural rubbers, but their special properties have made them more suitable than natural rubber for certain applications and they have ac
23、hieved a phenomenal technical importance.Reclaimed rubber is obtained by treating scrap vulcanized rubber by one of several methods, so that it becomes plastic again and can be handled on a mill and incorporated in a rubber compound, together with crude rubber.Reclaimed rubber contains all the ingre
24、dients of the original compound, except for the uncombined, or free sulfur. It was first used for economical resean that is to reduce the manufacturing cost. However, it was found that has also other advantages in addition to its lower cost. It fancilitates mastication and has very beneficial effect
25、 on calendaring and extruding. The quantity used varies to a great extent and some compounds are based exclusively on reclaimed rubber. However, reclaimed rubber affects some of the mechanical properties of the vulcanize ate unfavorably. Therefore, it is not used in case where high abrasion of tear
26、resistance or tensile strength is required.Now Words and Expressions1.natural 天然的,自然的,簡單的2.synthetic 人工的,合成的3.reclaim 收回,改正4.molecular 分子的5.hydrocarbon 烴,碳?xì)浠衔?.latex 膠乳7.coagulation 凝固,凝結(jié),凝聚8.producer 生產(chǎn)者9.Hevea Brasiliensis 巴西三葉橡膠樹10.wild 野生的11.quantity 數(shù)量,數(shù)12.protein 蛋白質(zhì)13.carbohydrate 碳水化合物14.re
27、sin-like 類樹脂的15.substance 物質(zhì)16.mineral 礦物,礦質(zhì)的17.salt 鹽mineral salt 金屬鹽18.fatty 脂肪的fatty acid 脂肪酸19.constituent 成分,組分20.accelerator 促進劑21.oxidant 氧化劑 anti-oxidant 防老劑,抗氧劑22.process 方法,過程23.exist 存在24.pure 純的,純凈的25.cis-polyisoprene 順式聚異戊二烯26.empirical 經(jīng)驗主義的,以經(jīng)驗為根據(jù)的27.formula 式,公式,配方28.structural 結(jié)構(gòu)上的2
28、9.extensible 可伸長的30.recovery 復(fù)原,復(fù)原性31.in fact 事實上,實際上32.incorrect 不正確的33.polymer 聚合物34.original 最初的,原來的35.i.e. 那就是,即36.strict 嚴(yán)格的37.identical 同一的,完全相同的38.artificial 人工的,人造的39.synthesise 合成,綜合40.usage 使用,用法,慣例,習(xí)慣41.refer 讀到,提到 refer to 參考,查閱,指42.define 解釋,給下定義43.relate 敘述,講,有關(guān),涉及(to)44 classify 分類,分級
29、,把分類45.state 陳述46.quality 質(zhì)量47.suitable 合適的48.application 使用,應(yīng)用49.phenomenal 驚人的50.scrape 刮,削,擦51.mill 開煉機52.incorporate 加入,綜合的pound 化合物,膠料54.crude 天然的,未加工的55.ingredient 配料,配合劑56.uncombined 未化合,未結(jié)合57.economical 經(jīng)濟的,節(jié)約的58.manufacture 制造59.cost 成本,花費60.in addition 另外61.facilitate 使容易,使便利,推進62.masticat
30、ion 塑煉63.beneficial 有益的,有利的64.calendar 壓延機,壓延65.extrude 擠出,壓出66.extent 范圍,廣闊,程度67.to be based on 以為根據(jù),根據(jù)68.exclusive 孤高的,排外的,專有的,唯一69.vulanizate 硫化膠 70.unfavorably 不利的,不順利地71.case 情況,事例72.abrasion 摩擦,磨損73.tear 撕裂74.resistance 抗耐性,耐力75.tensile 拉力的,抗張力的76.strength 力,強度Lesson FourVulcanizing Agents、Acc
31、elerators and ActivatorsDuring vulcanization, the long chain of the rubber molecules become crosslinked by reactions with the vulcanizing agent to form three-dimensional structures. In pratice, sulfur is used almost exclusively for vulcanization of rubber. Other vulcanizing agents, such as sulfur ch
32、loride, selenium, tellurium, and thiuram disulfide, are used only in special cases.Accelerations can increase the speed of reaction between sulphur and rubber, or lower the vulcanization temperature. They can also decrease the physical and technical properities of the vulcanizate.Inorganic accelerat
33、ors were discovered accidentally early in the history of the rubber industry when inorganic compounds were added go rubber as coloring agents and fillers. Among the basic salts and metal oxide recommended as accelerators, line, magnesium oxide, and litharge were the most common ones, litharge is sti
34、ll used to some extent, but its blackening effect on the vulcanizate limits its application to black compounds.Oenslagers discovery, in 1906, of the acceleration effect of aniline marked the beginning of a long line of organic accelerators which belong to many different groups.A very small quantity,
35、 about 1 per cent, of these organic compounds has a remarkable accelerating effect. Organic accelerators were classified according to their technical effects and were placed in the following categories:ultra-accelerators semi-ultra-accelerators medium-fast-acceleratorsslow acceleratorsActivators act
36、ivate accelerators. Most accelerators are much more active in presence of activators than they are alone. The activator reacts with the accelerators. As a result, an intermediate complex is formed. The complex is more effective in activating the sulphur present in the rubber mixture.There are two la
37、rge classes of activators: metal oxides and fatty acids. Representatives of both groups must be present simultaneously. The most common member of the first group is zinc oxide which is in the proportion of about 3 to 5 percent as activator in almost every rubber compound. The second group includes o
38、leic palmatic and especially stearic acid. They are used in amounts of 0.5 to 3 percent.New Words and Expressions1. agent 劑,媒介物,代理人2. activator 活化劑3. vulcanization 硫化4. chain 鏈,鏈條5. molecule 分子6. crosslink 交聯(lián)7. reaction 反應(yīng)8. dimensional 維的,度的,尺寸的9. structure 結(jié)構(gòu)10. chloride 氯化物11. selenium 硒12. tellu
39、rium 碲13. thiuram 秋蘭姆14. disulfide 二硫化物15. special 特殊的,專門的16. increase 增加,提高17. temperature 溫度18. decrease 減少,降低19. considerably 相當(dāng),大大地20. inorganic 無機的21. accidentally 意外地,無意地,偶然地22. recommend 介紹,推薦23. lime 氧化鈣,生石灰24. magnesium 鎂25. oxide 氧化物magnesium oxide 氧化鎂26. zinc 鋅27. litharge 一氧化鉛28. limit 限
40、制,限度29. aniline 苯胺30. organic 有機的31. remarkable 顯著的,明顯的32. according 依照according to 按照,依據(jù)33. technical 技術(shù)的,專門的34. category 種類,部門,范疇35. ultra 超,過渡的ultra-accelerators 超促進劑36. semi 半37. medium 中等(的),適度,普通38. activate 活化39. intermediate 中間的40. complex 絡(luò)合物,合成物,復(fù)雜的41. effective 有效的42. representative 代表,代表的43. simultaneously 同時發(fā)生地,同時進行44. include 包括45. oleic 油酸的46. palmatic 棕櫚酸47. stearic acid 硬脂酸Lesson FiveFillersMost rubber products contain fillers which belong to two groups: reinfor
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