天童美语英语四级阅读模拟题及详解答案Word文件下载.docx

天童美语英语四级阅读模拟题及详解答案Word文件下载.docx

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　　[E]settle

　　[F]cautious

　　[G]cooperate

　　[H]greatly

　　[I]dropping

　　[J]hardly

　　[K]intense

　　[L]focus

　　[M]aspiration

　　[N]critical

　　[O]procedure

　　参考答案：

　　1.D

　　2.I

　　3.N

　　4.G

　　5.H

　　6.F

　　7.A

　　8.C

　　9.L

　　10.B

　　Here’stheTotallyAmazingWonderMaterialThatCouldRevolutionizeTechnology

　　A.Inthetechnologyindustry,everynewproductorserviceseemstocomewiththepromisethatitisaninnovationwiththepotentialtochangetheworld.Graphene（石墨烯），aformofcarbon，mightactuallydojustthat.

　　B.“Grapheneisawonderfulmaterial，”JeanieLau，aprofessorofphysicsattheUniversityofCaliforniaatRiverside，toldFortune.“Itconductsheat10timesbetterthancopperandelectricity100timesbetterthansilicon，istransparentlikeplastic，extremelylightweight,extremelystrong,yetflexibleandelastic.Inthepastdecade，ithastakenthescientificandtechnologycommunitiesbystorm，andhasbecomethemostpromisingelectronicmaterialtosupplementorreplacesilicon.”

　　C.Graphenehasalreadyfounditswayintoanumberofcompellingapplications，Lausaid.Forinstance，“sinceitisbothtransparentandelectricallyconductive—twoattributesrarelyfoundinthesamematerialinnature—ithastremendouspotentialasthetransparentelectrodeinmonitors.displays;

solarcells，andtouchscreens，”sheexplained.“CompaniessuchasSamsungthatinvestheavilyinthisareahavealreadysecuredpatents，producedprototypes，andareexpectedtobringproductstomarketinafewyears.”Wearableelectronicdevices，aviationcomponents，broadbandphotodetectors（光电检测器），radiation-resistantcoatings，sensors，andenergystorageareamongnumerousotherareasofactiveresearch.Lausaid.

　　D.Formanyresearchersandinvestors，theultimateapplicationisgraphene-basedtransistors，thebuildingblocksofmodemelectronics.Butgettingtheremaytakesometime.

　　Achildofgraphite

　　E.Firstproducedinalabbackin2004，grapheneisessentiallyasinglelayerofpurecarbonatomsbondedtogetherinahoneycomblatticesothinit’sactuallyconsideredtwo-dimensional.“Wegenerallyregardanythinglessthan10layersofgrapheneasgraphene;

otherwise，it’sgraphite，”saidAravindVijayaraghavan，alecturerinnanomaterialsattheUniversityofManchester.

　　F.Even“graphene”isabitofanumbrellaterm.“Tooversimplify,therearetwomajortypesofgraphene，”MichaelPatterson，CEOofGrapheneFrontiers，said.Thefirst：

“Nanoplatelets，”whicharepowdersorflakesmadefromgraphite.Thesehavebeenaroundforawhileandare“notreallysuper-sexy,”Pattersonsaid.“Youmixthemintopolymers（聚合物）orinksorrubberstomakethemconductive.”Inflakeform，grapheneisalreadyonitswaytobecomingacommodity,Pattersonadded.Theothertype—insheetorfilmform—iswheregraphene’sbiggestpromiselies.Graphenesheetshave“incrediblepotentialforelectronics，”Pattersonsaid.Inthenearterm，thatpotentialmaymanifestinsituationswherethequantityrequirementsare“notthatgreat”andwherequalityorconductivitydoesn’thavetobeashigh，suchasinbasictouch-screenapplications，hesaid.Productsthatusegrapheneinthiswaycouldarrivetomarketinthenextsixto12months.

　　G.Lookingalittlefurtherout，graphenecanbeemployedinmembranesusedforwaterdesalination.Lockheed-MartinalreadyhasapatentedproductknownasPerforene.“It’srealanditworks，butitwon’tbeeconomicallyviableuntiltheproductreachesanindustrialscalewherethecostismeasuredinpenniespersquareinch”ratherthandollarsortensofdollarspersquareinch，Pattersonexplained.

　　“That’swherewe’reworkingtoday.”

　　‘It’sexpensiveandlow-capacity’

　　H.Butuseofgrapheneinsemiconductors—thetechnology’sHolyGrail—islikelyadecadeaway.“Manyofthechallengespresentedbygraphenearecommontomostnewmaterials，”PaulSmith,apatentassociatewiththeIntellectualPropertyLawGroupatFenwick&

West，toldFortune.“Thetrickisfiguringouthowtosynthesizegrapheneinawaythatfirstismanufacturablebeyondlabscale;

second，preservesthedesirablepropertiesofthematerial;

andthird，canbeintegratedintoaproductortechnology.”

　　I.Synthesizinggrapheneinsheetformisconsiderablymoreexpensiveandtime-consumingthanproducinggrapheneflakes.Whereasthelattertypicallyinvolvesa“quickanddirty”processbywhichbulkgraphiteisdisassembledintomillionsoftinypieces，Lauexplained，largesheetsofgraphenearecarefully“grown”onsubstrates（基板）suchascopper，germanium，orsiliconcarbide.

　　J.Graphenesheetsarealsopronetodefectsand“verydifficulttomakeingoodquality,”RonMertens，ownerandeditorofGraphene-Info.tom，said.Productioncapacityisalsoverylimited.“Therearethousandsofsmallcompaniesthatcanmakegraphene，butit’sexpensiveandlow-capacity,”Mertenssaid.alroundwafermeasuringoneinchindiameter,forinstance，costsabout$100，headded.

　　K.Aneventhornierobstacleonthewaytographenetransistorsisthefactthatthematerialhasno“bandgap，”anessentialpropertythatallowstransistorstobeturnedonandoffwithoutleakingelectronicchargeinthe“off”state，saidEliasTowe，aprofessorofelectricalandcomputerengineeringatCarnegieMellonUniversity.

　　L.“Band-gapengineeringhasbeenandremainsthebiggestchallengeinthedevelopmentofgraphenetransistorsandcomputerchips.”Lausaid.Itrequirescontrollingthematerialalmostdownattheatomiclevel，and“that’sreallypushingtheedgesofexistingtechnology,”Pattersonsaid.“In10years，we’11starttoseetheseproblemssolved.”

　　‘Itislargelyamatteroftime’

　　M.Ifgrapheneistosucceedasareplacementforsilicon，everyunitofcostandperformancewillmakeadifference，Towesaid.

　　N.“Siliconishardtodisplace，withallthebillionsdollarsofinvestmentsmadeinmanufacturinginfrastructure，”hesaid.“Areplacementforsiliconhastoofferextraordinaryperformanceatextremelyrock-bottomcosttocompelindustrytochangeitsway.”

　　O.Thoughgrapheneisjust10yearsold—incontrast,useofsiliconintransistorsdatestotheearly1950s—considerableprogresshasalreadybeenmade.Forexample，thelargestgraphenesheetwasproducedbyhandinalaboratoryeightyearsago;

itswidthwaslessthanthatofahumanhair.“Nowadays，roll-to-rollprintingofgraphenesheetsupto100meterslonghasbeenachieved，”Lausaid.“Withtheincreasinginterest，investment，andresearchingraphene-basedtechnology,Ithinkitislargelyamatteroftimebeforetheeconomyofscalekicksinandtrulylow-cost，large-scaleproductionofhigh-qualitygrapheneisaccomplished，”sheadded.

　　46.Nanoplateletisthepowder-orflake-typeofgraphenethathasbeenusedforsometimetomakeconductorsandthatisbeinglaunchedonthemarket.

　　47.Toencourageindustrytoreplacesiliconwithgraphene，itisnecessaryforgraphenetoprovidehighpropertyatanextremelylowexpense.

　　48.Whilegrapheneflakesareroughlyprocessedwithbulkgraphite，graphenesheetsarecarefullymadeonsubstrateslikecopper，germanium，orsiliconcarbide.

　　49.Inthepasttenyears.graphenehasbecomeahottopicamongthescientificandtechnologygroups.

　　50.Perforenewon’tcomeintothemarketbeforeitcanbemanufacturedataverylowcost.

　　51.Despiteofamuchyoungeragethansilicon，greatprogresshasbeenmadeingraphene;

andwitheverincreasinginterest，investmentandresearchingraphenetechnology,it’sprobabletomanufacturecost-effectivegrapheneofhighquality.

　　52.Graphenehasbeenattemptedtobeusedforplentyofnoticeableapplications.

　　53.Yetitstillneedstotaketenyearsforgraphenetobeusedinsemiconductors，whichliesattheheartofthetechnology.

　　54.Withtoday’stechnology,itisstillimpossibletocontrolmaterialdownattheatomiclevel.

　　55.EliasTowepointedoutthathavingno“bandgap”，thedispensablefeatureoftransistors，makesitmoredifficulttoproducegraphenetransistors.

　　46.Nanoplateletisthepowder-orflake-typeofgraphenethathasbeenusedforsometimetomakeconductorsandthatisbeinglaunchedonthemarket.纳米片是粉末状或者薄片状的石墨烯，被用于制作导体已经有一段