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(完整word版)2014年雅思阅读模拟试题及答案解析(3)-推荐文档.doc

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Timetocoolit 1REFRIGERATORSaretheepitomeofclunkytechnology：solid，reliableandjustalittlebitdull.Theyhavenotchangedmuchoverthepastcentury，butthentheyhavenotneededto.Theyarebasedonarobustandeffectiveidea--drawheatfromthethingyouwanttocoolbyevaporatingaliquidnexttoit，andthendumpthatheatbypumpingthevapourelsewhereandcondensingit.Thismethodofpumpingheatfromoneplacetoanotherservedmankindwellwhenrefrigerators'mainjobswerepreservingfoodand，asairconditioners，coolingbuildings.Today'shigh-techworld，however，demandshigh-techrefrigeration.Heatpumpsarenolongeruptothejob.Thesearchisonforsomethingtoreplacethem. 2Onesetofcandidatesareknownasparaelectricmaterials.Theseactlikebatterieswhentheyundergoatemperaturechange：attachelectrodestothemandtheygenerateacurrent.Thiseffectisusedininfra-redcameras.Anarrayoftinypiecesofparaelectricmaterialcansensetheheatradiatedby，forexample，aperson，andthepatternofthearray'selectricaloutputscanthenbeusedtoconstructanimage.Butuntilrecentlynoonehadbotheredmuchwiththeinverseofthisprocess.Thatinverseexists，however.Applyanappropriatecurrenttoaparaelectricmaterialanditwillcooldown. 3SomeonewhoislookingatthisinverseeffectisAlexMischenko，ofCambridgeUniversity.Usingcommerciallyavailableparaelectricfilm，heandhiscolleagueshavegeneratedtemperaturedropsfivetimesbiggerthananypreviouslyrecorded.Thatmaybeenoughtochangethephenomenonfromalaboratorycuriositytosomethingwithcommercialapplications. 4Astowhatthoseapplicationsmightbe，DrMischenkoisstillalittlehazy.Hehas，nevertheless，setupacompanytopursuethem.Heforeseesputtinghisdiscoverytouseinmoreefficientdomesticfridgesandairconditioners.Therealmoney，though，maybeincoolingcomputers. 5Gadgetscontainingmicroprocessorshavebeengettinghotterforalongtime.OneconsequenceofMoore'sLaw，whichdescribesthedoublingofthenumberoftransistorsonachipevery18months，isthattheamountofheatproduceddoublesaswell.Infact，itmorethandoubles，becausebesidesincreasinginnumber，thecomponentsaregettingfaster.Heatisreleasedeverytimealogicaloperationisperformedinsid