大学英语四级级阅读理解每日一练Word下载.docx

大学英语四级级阅读理解每日一练Word下载.docx

《大学英语四级级阅读理解每日一练Word下载.docx》由会员分享，可在线阅读，更多相关《大学英语四级级阅读理解每日一练Word下载.docx（5页珍藏版）》请在冰豆网上搜索。

Recentresearchhasclaimedthatanexcessofpositiveionsintheaircanhaveanilleffectonpeoplesphysicalorpsychologicalhealth.WhatarepositiveionsWell，theairisfullofions，electricallychargedparticles，andgenerallythereisaroughbalancebetweenthepositiveandthenegativecharged.Butsometimesthisbalancebecomesdisturbedandalargerproportionofpositiveionsarefound.Thishappensnaturallybeforethunderstorm，earthquakeswhenwindssuchastheMistral，HamsinorSharavareblowingincertaincountries.Oritcanbecausedbyabuild-upofstaticelectricityindoorsfromcarpetsorclothingmadeofman-madefibres，orfromTVsets，duplicatorsorcomputerdisplayscreens.　　Whenalargenumberofpositiveionsarepresentintheairmanypeopleexperienceunpleasanteffectssuchasheadaches，fatigue，irritability，andsomeparticularlysensitivepeoplesuffernauseaorevenmentaldisturbance.Animalsarealsoaffected，particularlybeforeearthquakes，snakeshavebeenobservedtocomeoutofhibernation，ratstofleefromtheirburrows，dogshowlandcatsjumpaboutunaccountably.ThishasledtheUSGeographicalSurveytofundanetworkofvolunteerstowatchanimalsinanefforttoforeseesuchdisastersbeforetheyhitvulnerableareassuchasCalifornia.　　Conversely，whenlargenumbersofnegativeionsarepresent，thenpeoplehaveafeelingofwell-being.Naturalconditionsthatproducetheselargeamountsarenearthesea，closetowaterfallsorfountains，orinanyplacewherewaterissprayed，orformsaspray.Thisprobablyaccountsforthebeneficialeffectofaholidaybythesea，orinthemountainswithtumblingstreamsorwaterfalls.　　Toincreasethesupplyofnegativeionsindoors，somescientistsrecommendtheuseofionisers：

smallportablemachines，whichgeneratenegativeions.Theyclaimthationisersnotonlycleanandrefreshtheairbutalsoimprovethehealthofpeoplesensitivetoexcesspositiveions.Ofcourse，therearethedetractors，otherscientists，whodismisssuchclaimsandareskepticalaboutnegative/positiveionresearch.Thereforepeoplecanonlymakeuptheirownmindsbyobservingtheeffectsonthemselves，oronothers，ofanegativerichorpoorenvironment.Afterallitisdebatablewhetherdependingonseismicreadingstoanticipateearthquakesismoreeffectivethanwatchingthecat.

1.Whateffectdoesexceedingpositiveionizationhaveonsomepeople

A.Theythinktheyareinsane.　　B.Theyfeelratherbad-temperedandshort-fussed.　　C.Theybecomeviolentlysick.　　D.Theyaretootiredtodoanything.

2.Inaccordancewiththepassage，staticelectricitycanbecausedby___.

A.usinghome-madeelectricalgoods.　　B.wearingclothesmadeofnaturalmaterials.　　C.walkingonartificialfloorcoverings.　　D.copyingTVprogramsonacomputer.

3.Ahighnegativeioncountislikelytobefound___.

A.nearapoundwithawaterpump.　　B.closetoaslow-flowingriver.　　C.highinsomebarrenmountains.　　D.byarotatingwatersprinkler.

4.Whatkindofmachinecangeneratenegativeionsindoors

A.Ionisers.　　B.Air-conditioners.　　C.Exhaust-fans　　D.Vacuumpumps.

5.Somescientistsbelievethat___.

A.watchinganimalstoanticipateearthquakesismoreeffectivethandependingonseismography.

B.theunusualbehaviorofanimalscannotbetrusted.

C.neitherwatchingnorusingseismographsisreliable.

D.earthquake

答案：

BCDAA

二

Whichissafer-stayingathome，travelingtoworkonpublictransport，orworkingintheofficeSurprisingly，eachofthesecarriesthesamerisk，whichisverylow.However，whataboutflyingcomparedtoworkinginthechemicalindustryUnfortunately，theformeris65timesriskierthanthelatter!

Infact，theaccidentrateofworkersinthechemicalindustryislessthanthatofalmostanyofhumanactivity，andalmostassafeasstayingathome.

Thetroublewiththechemicalindustryisthatwhenthingsgowrongtheyoftencausedeathtothoselivingnearby.Itisthiswhichmakeschemicalaccidentssonewsworthy.Fortunately，theyareextremelyrare.ThemostfamousoneshappenedatTexasCity（1947），Flixborough（1974），Seveso（1976），Pemex（1984）andBhopal（1984）。

Someofthesearealwaysinthemindsofthepeopleeventhoughthelossoflifewassmall.NoonediedatSeveso，andonly28workersatFlixborough.TheworstaccidentofallwasBhopal，whereupto3，000werekilled.TheTexasCityexplosionoffertilizerkilled552.ThePemexfireatastorageplantfornaturalgasinthesuburbsofMexicoCitytook542lives，justamonthbeforetheunfortunateeventatBhopal.

Someexpertshavediscussedtheseaccidentsandusedeachaccidenttoillustrateaparticulardanger.ThustheTexasCityexplosionwascausedbytonsofammoniumnitrate（硝酸铵），whichissafeunlessstoredingreatquantity.TheFlixboroughfireballwasthefaultofmanagement，whichtoo