首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Air Pollution Air pollution is typically caused by【1】_____ran by the factories of modern industrial na-
Air Pollution Air pollution is typically caused by【1】_____ran by the factories of modern industrial na-
admin
2012-12-30
68
问题
Air Pollution
Air pollution is typically caused by【1】_____ran by
the factories of modern industrial na- 【1】_____
tions, automobiles, trains, planes, and buses. Each year, plenty of wastes get into the air.
It does great harm to people,
【2】_____the eyes and chests. Many people become ill, and the 【2】_____
death raw among elderly people and people with lung disorders climbs rapidly caused by a weather 【3】 【3】_____
_____called a temperature【4】_____. 【4】_____
At least half of the pollutants in the air come from the engines of motor vehicles. As they burn
fuel, they give off carbon monoxide as a waste, a colorless, odorless gas, and a deadly poison. Thisproblem can be solved by special devices designed to
make the engine burn the fuel more【5】_____. 【5】_____
Some manufacturers use electricity or other means that will reduce pollution.
Coal and oil are also an important resource of waste.
It is irritating to the【6】_____. Sonic 【6】_____
cities have passed laws that allow coal and oil to be burned only if their sulfur content is low. Thereis no air pollution of the ordinary kind. But the【7】_____materials in these plants could present a 【7】_____
danger in an accident. Also, there is a problem in disposing of the radioactive wastes in a way that will not endanger the environment.
Another type of pollution, called heat pollution,
is caused by both the fuel-burning and【8】 【8】_____
_____plants. It may also kill fish and their eggs, or【9】_____with their growth. 【9】_____
Totally, physicists,
many power plants and【10】_____should work together to study new 【10】____
ways of generating electricity.
【4】
Air Pollution
A great deal of energy is needed to run the factories of modern industrial nations. Automobiles, trains, planes, and buses need energy, too. Nearly all of this energy is produced in the same way—by burning fuels. The burning produces wastes. Some of the wastes get into the air, causing air pollution.
Government officials in the United States estimate that 200, 000, 000 tons of these wastes enter the air each year—1 ton for each person in the country!
A curtain of smog often hangs over big cities. It irritates the eyes and chests. The word "smog" is a combination of the words "smoke" and "fog", but "smog" itself is a mixture of many more ingredients. It begins with some of the pollution from burning: carbon monoxide, and oxides of nitrogen and sulfur are among them. Some of the pollutants react with one another to form new irritating substances. Energy is needed for the reactions, and it is supplied by the light of the sun. The resulting mixture is photochemical smog. ("Photo" means light.) It can be deadly.
In London, Tokyo, New York, and other cities, a weather condition called a temperature inversion allows smog to hang over the city for several days at a time. Many people become ill, and the death rate among elderly people and people with lung disorders climbs rapidly.
At least half of the pollutants in the air come from the engines of motor vehicles. As they burn fuel, they give off carbon monoxide as a waste. Carbon monoxide is a colorless, odorless gas, and a deadly poison. The amount of carbon monoxide that an engine gives off can be reduced by special devices designed to make the engine burn the fuel more efficienfiy.
Automobile manufacturers are working on experimental cars run by electricity or other means that will reduce pollution. City governments in various parts of the world have begun to close certain streets to automobile traffic, hoping to lower pollution levels. Many city planners believe that cities, or at least their central areas should be kept free of automobiles.
Motor vehicles are not the only air polluters. Coal and oil, used to heat homes and factories and to generate electricity, contain small amounts of sulfur. When the fuels are burned, sulfur dioxide, a poisonous gas, is produced. It is irritating to the lungs. Sonic cities have passed laws that allow coal and oil to be burned only if their sulfur content is low.
Most electricity is generated by steam turbines. About half of the sulfur ,dioxide in the air comes from burning fuel to make steam. Nuclear power plants do not burn fuel, so there is no air pollution of the ordinary kind. But the radioactive materials in these plants could present a danger in an accident. Also, there is a problem in disposing of the radioactive wastes in a way that will not endanger the environment.
Another type of pollution, called thermal (heat) pollution, is caused by both the fuel-burning and nuclear plants. Both need huge amounts of cold waters which is warmed as it cools the steam. When it is returned to the river, the warm water may stimulate the growth of weeds. It may also kill fish and their eggs, or interfere with their growth.
Physicists are studying new ways of generating electricity that may be tess damaging to the environmeni. In the meantime, many power plants are being modernized to give off less polluting material. Also, engineers try to design and locate new power plants to do minimum damage to the environment.
选项
答案
inversion
解析
转载请注明原文地址:https://kaotiyun.com/show/2VaO777K
0
专业英语八级
相关试题推荐
ErnestHemingwayisoneofthemostfamousAmericannovelists,short-stowwritersandessayists,whosesimpleprosestyleinthe
I.CausesofBreakdownsin(1)【1】______1.Onstudents’part—insufficientcommandoverthe(2)ofEnglish【2】______—p
Beguninthelate1960sbyPentagonweaponsresearchersasasystemforeasingcommunicationbetweencomputersindisparateelec
SevenTypesofEvidenceItisimportanttolearntouseevidenceinargumentativewriting,becausewithoutevidence,youcan’t
Humour(alsospelledhumor)istheabilityorqualityofpeople,objects,orsituationstoevokefeelingsofamusementinother
TheFederalGovernmentsthecentralgovernmentoftheUnitedStates.Itisdividedintothreebranches:theExecutive,theLegi
Kidnappingsaroundtheworldhavetypicallyhadoneoftwomajorgoals:publicityforalocalpoliticalcauseorasaformof"f
TheEnglishVocabularyVocabularyisacompleteinventoryofthewordsinalanguage.Itcanbedividedintoactivevocabulary
A、ifheisfromtheEuropeanCommunityB、ifheisfromtheCommonwealthC、ifheintendstostayinUKformorethansixmonthsD
BythetimeIbeganteachingintheearly1970s,everyonealreadyseemedtobeinbusinessforhimself,lookingforthebestdea
随机试题
Theyare____ofdifferentpresses(出版社).Nowtheyarehavingameetinginoneofthe____office.
男孩,3岁,低热,稍咳2天,今全身可见水疱疹,诊断为水痘。去年因患肾病住院治疗至今。有关水痘,以下哪项是错误的
混凝土重力坝中横缝的主要作用是()。
自动化仪表分项工程应按仪表类别和()划分。
某项目的基准收益率i0=14%,其净现值NPV=18.8万元。现为了计算其内部收益率,分别用i1=13%,i2=16%,i3=17%进行试算,得出NPV1=33.2万元,NPV2=一6.1万元,NPV3=-10.8万元。则采用内插法求得的最接近精确解的内部
设计市场风险限额体系时应综合考虑的因素包括()。Ⅰ.自身业务性质,规模和复杂程度Ⅱ.内部控制水平Ⅲ.压力测试结果Ⅳ.能够承担的市场风险水平
下列车辆免征车辆购置税的有()。
下列对世界科技革命的说法不成立的是:
Comparisonsweredrawnbetweenthedevelopmentoftelevisioninthe20thcenturyandthediffusionofprintinginthe15thand1
Comparisonandcontrastareoftenused______inadvertisements.
最新回复
(
0
)