包邮化学化工基础英语

    近年来，高职高专商务英语专业的毕业生进入化工企业工作时，*大的困难是缺乏化学
化工知识、化学化工英语词汇、术语等，对仪器和设备的英文表达了解也不多。为了使学生
毕业后能尽快胜任化学化工外贸工作，化学化工类高职院校商贸英语专业开设化学化工基础
英语课程十分必要，为此化学工业出版社组织编写了本教材。
    本书选材来源于原版英文书籍、杂志、英语化学化工网站、国内外知名企业仪器设备样
本等资料。由三个部分20个单元构成，每个单元由课文、难点注释、词汇表、课后练习和
阅读材料组成。课文主要内容有无机化合物、有机化合物、高分子聚合物的命名和性质，精
细化工产品、分析检验仪器设备和化工生产设备的介绍，还包括相关企业和涉及化工产品的
品名、性质、储存、包装和危险品等级等内容。书后附有练习答案、课文中文参考译文、总
词汇表、化学化工常用构词、常见有机基团、常见有机化合物命名、元素名称及读法、常用
化工产品英文缩写与中文名称对照表等可供查阅。
    本书内容语言精炼、知识性强、覆盖面广、难度适中，可作为高职高专商务英语专业的
补充教材，也可作为高职高专化学化工专业英语教材，还可作为从事化工商贸活动和化工生
产、管理、经营、销售等专业人员的参考资料。
    本教材由天津渤海职业技术学院刘庆文担任主编，马竟担任副主编，天津渤海化工联合
进出口公司肖扬主审。其中第1～6单元由马竟编写，第7～13、15单元由刘庆文编写，第
14、16～20单元由湖南化工职业技术学院陈文娟编写，全书由刘庆文统稿。
    在本书编写过程中得到了许多同志的鼎力支持和热情帮助，中国远大集团远大海外经济
投资发展有限公司副总裁南泉、天津渤海化工集团公司教育培训中心常务副主任杨厚俊同
志、天津渤海化工联合进出口公司李锡琴、王艳华和李嘉庆同志对本书的编写都给予了具体
的建议和指导，天津渤海职业技术学院的范琳老师帮助录入了许多材料，在此一并表示衷心
的感谢。
    本书虽然经过多次补充和完善，但限于编者水平，书中不足之处在所难免，恳请广大读
者指正。
    编者
    2007年9月16日

 Unit 10  Fine Chemicals
     The fine chemical industry is an industry to produce fine chemical products. Fine chemi-
cal products and special chemical products are both called fine chemicals. Fine chemicals are
divided into 11 categories of pesticides, dyestuffs, coatings (including paints and inks), pig-
ments, reagents and high-purity chemicals, information chemicals (including photosensitive
materials and magnetic recording materials), food and feed additives, adhesives, catalysts
and auxiliaries, chemical drugs and chemicals for daily use.
                                          Pesticide
     Pesticide is biological, physical, or chemical agent used to kilt plants or animals that are
harmful to people in practice, the term pesticide is often applied only to chemical agents.
Various pesticides are known as insecticides, nematicides, fungicides, herbicides, and ro-
denticides, i. e. , agents primarily effective against insects, nematodes  or roundworms),
fungi, weeds, and rodents, respectively.
      Pesticides can be derived from plants (e. g. , pyrethrin, neem) or minerals, or they can
be chemically manufactured (e. g. , DDT, dich loro-diphenyltrichloroethane). Natural preda-
tors and other biological methods are also used. Among the biological agents, parasites and
predators feed on pests, pathogens sicken them, and pheromones interfere with insect mat-
ing. There are also genetically engineered pesticides, such as the toxin-producing Bacillus
strain used against moth larvae.
      Chemical pesticides are usually contact, stomach, or fumigant poisons. Contact poisons
may have immediate or delayed effects after physical contact with a pest. Fumigants, which
may initially have the form of a solid, liquid, or gas, kill pests while in a gaseous state.
      Some insecticides and fungicides are systemic, i.e. , they are translocated by a plant
from the area of application to other plant parts, where they affect only pests that feed on the
crop~. Nonselective pesticides can affect both the targeted pest and other organisms; selective
pesticides affect only the target pest. Persistent pesticides are those that remain in the envi-
ronment for a long time.
                                             Dye
      Dye is any substance, natural or synthetic, used to color various materials, especially
textiles, leather, and food. Natural dyes are so called because they are obtained from plants
(e. g. , alizarin, catechu, indigo, and logwood), from animals (e. g. , cochineal, kermes,
and Tyrian purple), and from certain naturally occurring minerals (e. g. , ocher and Prussian
blue). They have been almost entirely replaced in modern dyeing by synthetic dyes. Most of
these are prepared from coal tar, being formed from an aromatic hydrocarbon such as ben-
zene, from which indigo is derived, or anthracene, which yields alizarinz. Although some
 materials, e. g. , silk and wool, can be colored simply by being dipped in the dye (the dyes so
used are consequently called direct dyes), others, including cotton, commonly require the
use of a mordant. Alizarin is a mordant dye and the color it gives depends upon the mordant
used. Dyes are classified also as acidic or basic according to the medium required in the dyeing
process. A vat dye, e. g. , indigo, is so called from the method of its application; it is first
treated chemically so that it becomes soluble and is then used for coloring materials bathed in
a vat. When the materials become impregnated with the dye, they are removed and dried in
air, the indigo reverting to its original, insoluble form. The process by which a dye becomes
"attached" to the material it colors is not definitely known. One theory holds that a chemical
reaction takes place between the dye and the treated fiber; another proposes that the dye is
absorbed by the fiber.
                                          Pigment
      Pigment is a substance that imparts color to other materials. In paint, the pigment is a
powdered substance which, when mixed in the liquid vehicle, imparts color to a painted sur-
face. The pigments used in paints are nearly all metallic compounds, but organic compounds
are also used. Most black pigments are organic, e. g. , bone black (animal black or charcoal)
and lampblack. Some of the metallic pigments occur naturally. The brilliant and beautiful col-
oring of the rock and soil in some parts of the world. Yellow ocher, sienna, and umber are
oxides of iron. Litharge is a yellow oxide of lead. Red lead is also an oxide of this metal. Lead
chromate, or chrome yellow, is an important yellow pigment. White lead, or basic lead car-
bonate, is a pigment long in use; it is rendered more durable by mixture with zinc ox-
ide. Cadmium yellow is a sulfide of cadmium. Ultramarine is an important blue pigment, as is
Prussian blue (ferric ferrocyanide). Green pigment is produced by mixing Prussian blue and
chrome yellow. Vermilion (mercuric sulfide) is red. Pigments occur in plant and animal
bodies. The bright colors of plants, for example, are the result of the presence of such sub-
stances as chlorophyll (green) and xanthophyll (yellow), both of which are also found in
some animals. Among others are carotene, the yellow of carrots and certain other vegetables,
and anthocyanin, which imparts blue, red, and purple to flowers4. Blood receives its color
from the hemoglobin in the red corpuscles. Coloration of human skin is caused by the pres-
ence of pigments.
                                          Reagent
     A reagent or reactant is a material used to start a chemical reaction. For example hydro-
chloric' acid is the chemical reagent that would cause calcium carbonate to release carbon di-
oxide. Similarly, but less obvious, hydrochloric acid is the chemical reagent that reacts with
zinc to produce hydrogen, even though in this case the hydrogen comes from the acid and not
the metal. To classify any of the chemicals involved in a chemical reaction as the "reagent" is
thus largely a matter of convention or perspective.
     In another use of the term, when purchasing or preparing chemicals, "reagent" de-
 scribes chemical substances of sufficient purity for use in chemical analysis, chemical reac-
tions or physical testing. Purity standards for reagents are set by organizations such as
ASTM International. For instance, reagent-quality water must have very low levels of impu-
rities like sodium and chloride ions, silica, and bacteria, as well as a very high electrical re-
sistivity.
                                          Adhesive
      Adhesive is substance capable of sticking to surfaces of other substances and bonding
them to one another. The term adhesive cement is sometimes used in place of adhesive, espe-
cially when referring to a synthetic adhesive. Animal glue, a gelatin made from hides,
hooves, or bones, was probably known in prehistoric times; it remained the leading adhesive
until the 20th cent. It is now used especially in cabinetmaking. Animal glue is sold both as a
solid (either ground or in sheets, to be melted in a water-jacketed glue pot and applied while
hot) and as liquid glue (an acidic solution). Adhesives from vegetable sources are also impor-
tant; they include natural gums and resins,  mucilage,  and starch and starch deriva-
tives. They are commonly used for sizing paper and textiles and for labeling, sealing, and
manufacturing paper goods. Other adhesives derived from animal and vegetable sources in-
clude blood  glue,  casein  glue,  fish  glue,  rubber  adhesives,  and  cellulose  deriva-
tives. Adhesives having special properties are prepared from synthetic resins. Some synthetic
adhesives, such as the epoxy resins, are strong enough to be used in construction in place of
welding or riveting. Adhesive tapes have a coating of pressure-sensitive adhesive.
                                           Catalyst
      Catalyst is substance that can cause a change in the rate of a chemical reaction without
itself being consumed in the reaction. Substances that increase the rate of reaction are called
positive catalysts or, simply, catalysts, while substances that decrease the rate of reaction
are called negative catalysts or inhibitors.
      Enzymes are the commonest and most efficient of the catalysts found in nature. Most of
 the chemical reactions that occur in the human body and in other living things are high-ener-
gy reactions that would occur slowly, if at all, without the catalysis provided by en-
zymes. For example, in the absence of catalysis, it takes several weeks for starch to hydro-
 lyze to glucose; a trace of the enzyme ptyalin, found in human saliva, accelerates the reaction
 so that starches can be digested. Some enzymes increase reaction rates by a factor of one bil-
 lion or more. Enzymes are generally specific catalysts; that is, they catalyze only one reaction
 of one particular reactant (called its substrate). Usually the enzyme and its substrate have
 complementary structures and can bond together to form a complex that is more reactive due
 to the presence of functional groups in the enzyme, which stabilize the transition state of the
 reaction or lower the activation energy. The toxicity of certain substances (e. g. , carbon
 monoxide and the nerve gases) is due to their inhibition of life-sustaining catalytic reactions
 in the body.