首页
登录
职称英语
【1】 [br] 【5】 [originaltext] Chemistry deals with the materials of which the w
【1】 [br] 【5】 [originaltext] Chemistry deals with the materials of which the w
游客
2025-01-10
11
管理
问题
【1】 [br] 【5】
Chemistry deals with the materials of which the world is composed and the changes they many undergo. All of us, whether we are farmers, merchants, doctors, mechanics, chemists, housewives, or students, use this science directly or indirectly in a thousand ways every day. Our lives are made longer, healthier, richer, more convenient, and more pleasant because of chemistry.
We need only consider our daily routine activities to appreciate the part chemistry plays in everyday life. The clock that wakes us in the morning probably has in its mechanism half a dozen different metals or alloys, all of which were prepared by chemical processes. The clothes we put on were bleached and dyed chemically, or perhaps woven from synthetic materials produced by chemical processes devised by man. The leather in our shoes was tanned and dyed with chemicals. The water with which we wash is chemically treated to purify, and, sometimes, to soften it. The soap, toothpaste, shaving cream or cosmetics we use are all chemical products. Chemistry is involved in the glass and silvering of the mirror, in the manufacture of light bulbs, and the paint and plaster on our walls. The food for breakfast is cooked, digested, and assimilated in our bodies by chemical processes. We drive to work or school in and automobile which may Be constructed of a hundred different kinds of steel, to say nothing of the other metals and alloys, plastics, rubber, and fuels and lubricants which power or protect it. All of these were prepared by chemical processes.
The science of medicine draws heavily upon chemistry, and many of us are alive today because of chemical products. Evidence indicates that, in ancient Rome, life expectancy averaged 22 years. Yet, in 1912 life expectancy in the United States averaged about 49 years. Now it has reached 70 for men and 73 for women. Chemistry and its products have played an important part in this increase in the life span of man.
Modern surgery is dependent upon anesthetics and antiseptics. Ether was first used as an anesthetic by Long in 1842. Chloroform was used a few years later. Before that time the patient might have been given opium derivatives or whiskey, or he might simply have been held down. Surgery was necessarily very crude and limited. Semmelweis in 1847 discovered that the hands, instruments, and clothing of the doctor could carry infection, and demanded that doctors maintain higher standards of cleanliness. In 1877 in Germany, Koch proved that germs caused disease or infection, and that they could often be controlled by chemicals. Pasteur’s work on the destruction of bacteria in food was done in the early 1860s.
The sulfa drugs developed in the 1930s proved to be powerful weapons against disease, and a little later the antibiotics were an even more important breakthrough in the fight against germs. Epidemics of typhus, cholera, diphtheria, and smallpox, which once swept the land, bringing death or disfiguration, are virtually a thing of the past now in most of the world. Chemistry bas played a mighty part in their defeat. The great strides being made in modern medicine are largely the result of an increasing knowledge of the chemical reactions that take place in the most complex of all chemical systems, the human body. Fortunately, most of us do not need a profound knowledge of chemistry in order to use the chemical processes and chemical products of modern living. Some understanding of the principles, processes, and applications of chemistry, nevertheless, should be a part of the background of every educated person.
选项
答案
materials
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3906466.html
相关试题推荐
[originaltext]PassageOne:Chinaisrichinwildlifespecies.Thereareabo
[originaltext]PassageOne:Chinaisrichinwildlifespecies.Thereareabo
[originaltext]1.ApartfromthefactthatChinaisoneofthefastestgrowinge
[originaltext]1.ApartfromthefactthatChinaisoneofthefastestgrowinge
[originaltext]IfirstwenttotheAmazonbasinin1974,ononeofmyfirst
[originaltext]W:Whatpeoplelearnisthattheyareinthehandsofassassins.
[originaltext]W:Whatpeoplelearnisthattheyareinthehandsofassassins.
[originaltext]W:Whatpeoplelearnisthattheyareinthehandsofassassins.
[originaltext]Ahigh-poweredZimbabweandelegation,whichisoptimistictha
[originaltext]Ahigh-poweredZimbabweandelegation,whichisoptimistictha
随机试题
Whatistheconversationmainlyabout?[br][originaltext]W:Bob,youwenttoB
FiveCommonMistakesinConversationsandTheirSolutionsI.NotlisteningA
SummaryListentothepassage.Forquestions26-30,completethenotesusingno
Forwelloveracentury,onestreetinNewYorkCityhasbeenknownforthe
预应力混凝土桥梁用金属波纹管承受集中荷载作用下抗渗漏性能试验介质必须用纯水泥浆。
参与私募债券认购和转让的合格投资者应符合的条件有( )。?A.经有关金融监管部
()适用0.3‰的印花税税率。A.技术合同 B.建筑安装工程承包
慢性支气管炎所致阻塞性肺气肿多为A.小叶中央型 B.全小叶型 C.混合型
该小额贷款公司执行的贷款利率政策为( )。查看材料A.上限控制、下限放开
评价心功能最常用的检查方法是A.常规心电图 B.超声心动图 C.动态心电图
最新回复
(
0
)