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部分化學(xué)工程與工藝專業(yè)英語課文翻譯胡鳴劉霞編(已修改)

2024-11-09 23:25 本頁面
 

【正文】 1 Unit 1 Chemical Industry 化學(xué)工業(yè) of the Chemical Industry Although the use of chemicals dates back to the ancient civilizations, the evolution of what we know as the modern chemical industry started much more recently. It may be considered to have begun during the Industrial Revolution, about 1800, and developed to provide chemicals roe use by other industries. Examples are alkali for soapmaking, bleaching powder for cotton, and silica and sodium carbonate for glassmaking. It will be noted that these are all inanic chemicals. The anic chemicals industry started in the 1860s with the exploitation of William Henry Perkin‘s discovery if the first synthetic dyestuff—mauve. At the start of the twentieth century the emphasis on research on the applied aspects of chemistry in Germany had paid off handsomely, and by 1914 had resulted in the German chemical industry having 75% of the world market in chemicals. This was based on the discovery of new dyestuffs plus the development of both the contact process for sulphuric acid and the Haber process for ammonia. The later required a major technological breakthrough that of being able to carry out chemical reactions under conditions of very high pressure for the first time. The experience gained with this was to stand Germany in good stead, particularly with the rapidly increased demand for nitrogenbased pounds (ammonium salts for fertilizers and nitric acid for explosives manufacture) with the outbreak of world warⅠ in 1914. This initiated profound changes which continued during the interwar years (19181939). 1. 化學(xué)工業(yè)的起源 盡管化學(xué)品的使用可以追溯到古代文明時代,我們所謂的現(xiàn)代化學(xué)工業(yè)的發(fā)展卻是非常近代(才開始的)??梢哉J為它起源于工業(yè)革命其間,大約在 1800 年,并發(fā)展成為為其它工業(yè)部門提供化學(xué)原料的產(chǎn)業(yè)。比如制肥皂所用的堿,棉布生產(chǎn)所用的漂白粉,玻璃制造業(yè)所用的硅及 Na2CO3. 我們會注意到所有這些都是無機物。有機化學(xué)工業(yè)的開始是在十九世紀六十年代以 William Henry Perkin 發(fā)現(xiàn)第一種合成染料 —苯胺紫并加以開發(fā)利用為標志的。20 世紀初,德國花費大量資金用于實用化學(xué)方面的重點研究,到 1914 年,德國的化學(xué)工業(yè)在世界化學(xué)產(chǎn)品市場上占有 75%的份額。這要歸因于新染料的發(fā)現(xiàn)以及硫酸的接觸法生產(chǎn)和氨的哈伯生產(chǎn)工藝的發(fā)展。而后者需要較大的技術(shù)突破使得化學(xué)反應(yīng)第一次可以在非常高的壓力條件下進行。這方面所取得的成績對德國很有幫助。特別是由于 1914 年第一次世界大仗的爆發(fā),對以氮為基礎(chǔ)的化合物的需求飛速增長。這種深刻的改變一直持續(xù)到戰(zhàn)后( 19181939)。 date bake to/from: 回溯到 dated: 過時的,陳舊的 stand sb. in good stead: 對。很有幫助 Before reading the text below, try to answer following question: 1. When did the modern chemical industry start? 2. Can you give a definition for the chemical industry? 3. What are the contribution which the chemical industry has made to meet and satisfy our needs? 4. Is the chemical industry capital or laborintensive? Why? 2 Since 1940 the chemical industry has grown at a remarkable rate, although this has slowed significantly in recent years. The lion‘s share of this growth has been in the anic chemicals sector due to the development and growth of the petrochemicals area since 1950s. The explosives growth in petrochemicals in the 1960s and 1970s was largely due to the enormous increase in demand for synthetic polymers such as polyethylene, polypropylene, nylon, polyesters and epoxy resins. 1940 年以來,化學(xué)工業(yè)一直以引人注目的速度飛速發(fā)展。盡管這種發(fā)展的速度近年來已大大減慢?;瘜W(xué)工業(yè)的發(fā)展由于 1950 年以來石油化學(xué)領(lǐng)域的研究和開發(fā)大部分在有機化學(xué)方面取得。石油化工在 60 年代和 70 年代的迅猛發(fā)展主要是由于人們對于合成高聚物如聚乙烯、聚丙烯、尼龍、聚脂和環(huán)氧樹脂的需求巨大增加。 The chemical industry today is a very diverse sector of manufacturing industry, within which it plays a central role. It makes thousands of different chemicals which the general public only usually encounter as end or consumer products. These products are purchased because they have the required properties which make them suitable for some particular application, . a nonstick coating for pans or a weedkiller. Thus chemicals are ultimately sold for the effects that they produce. 今天的化學(xué)工業(yè)已經(jīng)是制造業(yè)中有著許多分支的部門,并且在制造業(yè)中起著核心的作用。它生產(chǎn)了數(shù)千種不同的化學(xué)產(chǎn)品,而人們通常只接觸到終端產(chǎn)品或消費品。這些產(chǎn)品被購買是因為他們具有某些性質(zhì)適合(人們)的一些特別的用途,例如,用于盆的不粘涂層或一種殺蟲劑。這些化學(xué)產(chǎn)品歸根到底是由于它們能產(chǎn)生的作用而被購買的。 2. Definition of the Chemical Industry At the turn of the century there would have been little difficulty in defining what constituted the chemical industry since only a very limited range of products was manufactured and these were clearly chemicals, ., alkali, sulphuric acid. At present, however, many intermediates to products produced, from raw materials like crude oil through (in some cases) many intermediates to products which may be used directly as consumer goods, or readily converted into them. The difficulty cones in deciding at which point in this sequence the particular operation ceases to be part of the chemical industry‘s sphere of activities. To consider a specific example to illustrate this dilemma, emulsion paints may contain poly (vinyl chloride) / poly (vinyl acetate). Clearly, synthesis of vinyl chloride (or acetate) and its polymerization are chemical activities. However, if formulation and mixing of the paint, including the polymer, is carried out by a branch of the multinational chemical pany which manufactured the ingredients, is this still part of the chemical industry of does it mow belong in the decorating industry? 2. 化學(xué)工業(yè)的定義 在本世紀初,要定義什么是化學(xué)工業(yè)是不太困難的,因為那時所生產(chǎn)的化學(xué)品是很有限的,而且是非常清楚的化學(xué)品,例如,燒堿,硫酸。然而現(xiàn)在有數(shù)千種化學(xué)產(chǎn)品被生產(chǎn),從一些原料物質(zhì)像用于制備許多的半成品的石油,到可以直接作為消費品或很容易轉(zhuǎn)化為消費品的商品。困難在于如何決定在一些特殊的生產(chǎn)過程中哪一個環(huán)節(jié)不再屬于化學(xué)工業(yè)的活動范疇。舉一個特殊的例子來描述一下這種困境。乳劑漆含有聚氯乙烯 /聚醋酸乙烯。顯然,氯乙烯(或醋酸乙烯)的合 成以及聚合是化學(xué)活動。然而,如果這種漆,包括高聚物,它的配制和混合是由一家制造配料的跨國化學(xué)公司完成的話,那它仍然是屬于化學(xué)工業(yè)呢還是應(yīng)當(dāng)歸屬于裝飾工業(yè)中去呢? 3 It is therefore apparent that, because of its diversity of operations and close links in many areas with other industries, there is no simple definition of the chemical industry. Instead each official body which collects and publishes statistics on manufacturing industry will have its definition as to which operations are classified as the chemical industry. It is important to bear this in mind when paring statistical information which is derived from several sources. 因此,很明顯,由于化學(xué)工業(yè)經(jīng)營的種類很多并在很多領(lǐng)域與其它工業(yè)有密切的聯(lián)系,所以不能對它下一個簡單的定義。相反的每一個收集和出版制造工業(yè)統(tǒng)計數(shù)據(jù)的官方機構(gòu)都會對如何屆定哪一類操作為化學(xué)工業(yè)有自己的定義。當(dāng)比較來自不同途徑的統(tǒng)計資料時,記住這點是很重要的。 3. T
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