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时间:2018-10-22
《2017职称英语《理工a》阅读理解练习题及答案》由会员上传分享,免费在线阅读,更多相关内容在应用文档-天天文库。
1、精品文档2017职称英语《理工A》阅读理解练习题及答案Anundergroundrevolutionbeginsthiswinter.Withtheflip(轻击)ofaswitch,0,000homesinonepartofDetroitwillsoonbecom#ethefirstinthecountrytoreceiveelectricitytransmittedbyice-coldhigh-performancecables.OtherAmericancitiesareexpectedtofollowDetroit’sexampl
2、eintheyearsahead,whichcouldconserveenormousamountsofpower.ThenewelectricalcablesattheFrisbiepowerstationinDetroitarerevolutionarybecausetheyaremadeofsuperconductors.Asuperconductorisamaterialthattransmitselectricitywithlittleornoresistance.Resistanceisthedegreetowhichasub
3、stanceresistselectriccurrent.Allcom#monelectricalconductorshaveacertainamountofelectricalresistance.Theyconvertatleastsomeoftheelectricalenergypassingthroughthemintowasteheat.Superconductorsdon’t.Nooneunderstandshowsuperconductivityworks.Itjustdoes.Makingsuperconductorsis
4、n’teasy.Asuperconductormaterialhastobecooledtoanextremelylowtemperaturetoloseitsresistance.The2016全新精品资料-全新公文范文-全程指导写作–独家原创9/9精品文档firstsuperconductors,mademorethan0yearsago,hadtobecooledto-26degreesCelsiusbeforetheylosttheirresistance.Newersuperconductingmaterialslosethei
5、rresistanceat-14degreesCelsius.ThesuperconductorscableinstalledattheFrisbiestationismadeofaceramicmaterialthatcontainscopper,oxygen,bismuth(铋),strontium(锶),andcalcium(钙).Aceramicisahard,strongcom#poundmadefromclayorminerals.Thesuperconductingceramichasbeenfashionedintoata
6、pethatiswrappedlengthwisearoundalongtubefilledwithliquidnitrogen.Liquidnitrogenissupercoldandlowersthetemperatureoftheceramictapetothepointwhereitconveyselectricitywithzeroresistance.TheUnitedStateslosesanenormousamountofelectricityeachyeartoresistance.Becausecooledsuperc
7、onductorshavenoresistance,theywastemuchlesspower.OthercitiesarewatchingtheFrisbieexperimentinthehopethattheymightswitchtosuperconductingcableandconservepower,too.1.Whatisthebenefitoftherevolutionmentionedinthefirst2016全新精品资料-全新公文范文-全程指导写作–独家原创9/9精品文档paragraph?A.Withaflipo
8、fswish,electricitycanbetransmitted.B.OtherAmericancitiescanbenefitfromthehigh-performancecables.
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