化工類中英文文獻(xiàn)以及翻譯-化學(xué)工程-展示頁
2025-01-31 07:52本頁面
【正文】 en 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? 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. 3. The Need for Chemical Industry The chemical industry is concerned with converting raw materials, such as crude oil, firstly into chemical intermediates and then into a tremendous variety of other chemicals. These are then used to produce consumer products, which make our lives 3 more fortable or, in some cases such as pharmaceutical produces, help to maintain our wellbeing or even life itself. At each stage of these operations value is added to the produce and provided this added exceeds the raw material plus processing costs then a profit will be made on the operation. It is the aim of chemical industry to achieve this. It may seem strange in textbook this one to pose the question ―do we need a chemical industry?‖ However trying to answer this question will provide(ⅰ ) an indication of the range of the chemical industry’s activities, (ⅱ ) its influence on our lives in everyday terms, and (ⅲ ) how great is society’s need for a chemical industry. Our approach in answering the question will be to consider the industry’s contribution to meeting and satisfying our major needs. What are these? Clearly food (and drink) and health are paramount. Other which we shall consider in their turn are clothing and (briefly) shelter, leisure and transport. (1)Food. The chemical industry makes a major contribution to food production in at least three ways.
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