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      中學生英語演講稿the great race

      前言:本站為你精心整理了中學生英語演講稿the great race范文,希望能為你的創(chuàng)作提供參考價值,我們的客服老師可以幫助你提供個性化的參考范文,歡迎咨詢。

      中學生英語演講稿the great race

      英語演講稿

      thegreatrace

      automakersspeedtowardthefuture

      lastnight,wheniwassurfingonthenet,iwasattractedbyaword:

      hydrogeneconomy.ididn''''tknowwhatitmeant,andmaybemostofyou

      didn''''t,either.soiwentonreadingandfinallygotit.andtoday,ifeel

      soluckytotellyousomethingaboutit.andiamgoingtodividemy

      speechinto4parts.

      let''''sbeginourfirstpart.

      scienceorsciencefiction?

      iusedtoreadalotofsciencefiction.thefutureofenergyand

      transportationweresubjectsclosetomyheart.thelimitlesspowerof

      coldfusion.thewonderofmatter-antimatterreactors.thechallengeof

      dilithiumcrystalsandwarpdrive.ialmostbelievedit.iwantedto

      believeit.butasitturnsout,thefutureofenergyisandalwayshas

      beenallaroundus.itisasnaturalaswind,sunlightandwater.science

      overtakessciencefictionandgivesus…h(huán)ydrogen!iadmitthatitis

      terriblyanticlimactic.butthenwemustrealizethatthischanges

      everything.especiallyinenvironmentalprotection.butwhenwillthe

      hydrogeneconomygethere?

      powerfulmotivation

      prioritiesarechanging.youonceheardabouttheworld''''ssupplyofoil

      runningout,whichitis.weonceworriedabouttheecologicaleffectsof

      automobilepollution.butnow,thebattlecryissecurity.weneedenergy

      securityandpowermaderighthereathomeandlotsofit.wonderful,

      abundant,clean,renewable,sustainablepower.weneedtobeaboutthe

      taskoffindingalternativefuelsandenergysources.inthemeantime,we

      needtowanourselvesfromdependenceonmid-eastoil,useouroil,use

      ouroilmoreefficientlyand,almostasanafterthought,lowerlevelsof

      pollutionfromourvehicles.

      efficiencyandcleanliness,whileperhapsbeingnexttogodliness,have

      latelytakenabackseattosecurity.however,researchanddevelopment

      effortsaremutuallybeneficial.thenextgenerationoffuelwillbeboth

      cleanerandlocallymade.majorautomanufacturersandoilcompanieshave

      oftenbeenseenaspartoftheproblem(wecan''''tbuywhattheyrefuseto

      make).but,fromtheirperspective,theycan''''tsellwhatwedon''''twantto

      buy..tothem,itisourpenchantforgas-guzzlingsportsutilityvehicles

      thatisdangerous,wastefulandsuddenlyunpatriotic.

      hydrogensourcesandsupplyinfrastructure

      hydrogenisabundant,buttherearesupplyproblems.hydrogenisalmost

      neverfoundinitspureform.itisalreadycombinedwithotherelements

      toformwateroranynumberoforganiccompounds.togetpurehydrogen,

      youhavetoseparateitfromsomething.inthecaseofwater,theprocess

      iscalledelectrolysis.inhydrocarbonfuels,itiscalledreformation.

      althoughhydrogenhasbeensuccessfullyreformedfromallmajorfuels,

      industrialapplicationsforhydrogentodaygenerallyrelyonreformingit

      fromnaturalgas.thistechniquecanatbestbeashort-termsolutionif

      thegoalistobeindependentfromfossilfuels.othersourcesofhydrogen

      includeglucose,sodiumborohydrideandevenbacterialcomposting.notall

      ofthesewillmakethecut.renewabilityisakeyissue.themoney,time

      andefforttoturngtasfillingstations,hydrogenfillingstationsis

      mindandbudget-boggling.

      theotherproblemissupplyinfrastructure.themoney,timeandeffortto

      turngasfillingstations.thereisconsiderablementalenergygoinginto

      solvingtheseproblems,buttheywillnotbeso;vedquicklyorcheaply.at

      leastibelieve.

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