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
About two-thirds of the world’s population is expected to live in cities by the year 2020 and, according to the United Nations,
About two-thirds of the world’s population is expected to live in cities by the year 2020 and, according to the United Nations,
admin
2023-03-07
62
问题
About two-thirds of the world’s population is expected to live in cities by the year 2020 and, according to the United Nations, approximately 3.7 billion people will inhabit urban areas some 10 years later. As cities grow, so do the number of buildings that characterize them: office towers, factories, shopping malls and high-rise apartment buildings. These structures depend on artificial ventilation systems to keep clean and cool air flowing to the people inside. We know these systems by the term "air-conditioning"
Although many of us may feel air-conditioners bring relief from hot, humid or polluted outside air, they pose many potential health hazards. Much research has looked at how the circulation of air inside a closed environment—such as an office building—can spread disease or expose occupants to harmful chemicals.
One of the more widely publicized dangers is that of Legionnaire’s disease, which first recognized in the 1970s. This was found to have affected people in buildings with air-conditioning systems in which warm air pumped out of the system’s cooling towers was somehow sucked back into the air intake, in most cases due to poor design. This warm air was, needless to say, the perfect environment for the rapid growth of disease carrying bacteria originating from outside the building, where it existed in liarmless quantities. The warm, bacteria-laden air was combined with cooled conditioned air and was then circulated around various parts of the building. Studies showed that even people outside such buildings were at risk if they walked past air exhaust
ducts
. Cases of Legionnaire’s disease are becoming fewer with newer system designs and modifications to older systems, but many older buildings, particularly in developing countries, require constant monitoring.
The ways in which air-conditioners work to "clean" the air can inadvertently cause health problems, too. One such way is with the use of an electrostatic precipitator, which removes dust and smoke particles from the air. What precipitators also do, however, is to emit large quantities of positive air ions into the ventilation system. A growing number of studies show that overexposure to positive air ions can result in headaches, fatigue and feelings of irritation.
Large air-conditioning systems add water to the air they circulate by means of humidifiers. In older systems, the water used for this process is kept in special reservoirs, the bottoms of which provide breeding grounds for bacteria and fungi which can find their way into the ventilation system. The risk to human health from this situation has been highlighted by the fact that the immune systems of approximately half of workers in air-conditioned office buildings have developed antibodies to fight off the organisms found at the bottom of system reservoirs. Chemical disinfectants, called "biocides", that are added to reservoirs to make them germ-free are dangerous in their own right in sufficient quantities, as they often contain compounds such as pentachlorophenol, which is strongly linked to abdominal cancers.
Finally, it should be pointed out that the artificial climatic environment created by air-conditioners can also adversely affect us. In a natural environment, whether indoor or outdoor, there are small variations in temperature and humidity. Indeed, the human body has long been accustomed to these normal changes. In an air-conditioned living or work environment, however, body temperatures remain well under 37° C, our normal temperature. This leads to a weakened immune system and thus greater susceptibility to diseases such as colds and flu.
Bacteria came into a ventilation system when _____.
选项
A、cool air was sucked into it
B、warm air was sucked back
C、cool air was sucked back
D、warm air was sucked into it
答案
B
解析
由第3段第2、3句可知,由于设计不良,一些空调的热空气又会被吸进来,而热空气带有大量的细菌,故选B“当热空气被抽回时”。
转载请注明原文地址:https://kaotiyun.com/show/DXcD777K
本试题收录于:
CATTI三级笔译综合能力题库翻译专业资格(CATTI)分类
0
CATTI三级笔译综合能力
翻译专业资格(CATTI)
相关试题推荐
"Juststicktoscience."ThisisacommonadmonitionthatSciencereceiveswhenwepublishcommentariesandnewsstoriesonpoli
AdecadeagobiologistsidentifiedaremoteprotectedareainnorthernLaos,calledNamEt-PhouLouey,asthecountry’sprobable
Inflationisn’tnew,butpricerisescanstillshock.IrecentlyholidayedintheHamptons,atonybeachareaoutsideNewYork,
Peoplewhousuallychowdownonchillipeppersmayliveforlongerandhaveasignificantlyreducedriskofdyingfromcardiovas
WhydopeoplereadnegativeInternetcommentsanddootherthingsthatwillobviouslybepainful?Becausehumanshaveaninheren
Duringthelast15years,theEarth’ssurfacetemperatureroseatarateof0.04℃adecade,farslowerthanthe0.18℃)increase
Justsevenyearsago,theTexasLegislatureprescribedthatallhighschoolersmustpasstwomathcoursesandgeometrytogradua
Justsevenyearsago,theTexasLegislatureprescribedthatallhighschoolersmustpasstwomathcoursesandgeometrytogradua
TheaverageBritishpeoplegetsix-and-a-halfhours’sleepanight,accordingtotheSleepCouncil.Ithasbeenknownforsomet
Canada’spremiers(theleadersofprovincialgovernment),iftheyhaveanybreathleftaftercomplainingaboutOttawaattheirl
随机试题
甲恳求国有公司财务主管乙,从单位挪用10万元供他炒股,并将一块名表送给乙。乙做假账将10万元交与甲,甲表示尽快归还。20日后,乙用个人财产归还单位10万元。关于本案,下列哪一选项是错误的?()(2012/2/20)
阑尾炎时闭孔内肌试验阳性,其临床意义在于
A.一级召回B.二级召回C.三级召回D.无需召回使用医疗器械可能或者已经引起暂时的或者可逆的健康危害的,应实施
齐某在A市B区利用网络捏造和散布虚假事实,宣称刘某系当地黑社会组织“大哥”,A市中级法院院长王某为其“保护伞”。刘某以齐某诽谤为由,向B区法院提起自诉。关于本案处理,下列哪一选项是正确的?(2017年卷二24题)
财政政策的种类大致可以分为()
业主委员会与业主大会选聘的物业管理企业订立的书面物业服务合同内容中应包括的内容有()等。
Alanworkedinanofficeinthecity.Heworkedveryhardandreallylookedforwardtohisholiday.Heusuallywenttotheseasi
Giventhatmanypeople’smoods(情结)areregulatedbythechemicalactionofchocolate,itwasprobablyonlyamatteroftimebef
抵销与提存
Readingtooneselfisamodernactivitythatwasalmostunknowntothescholarsoftheclassicalandmedievalworlds,whileduri
最新回复
(
0
)