首页
试卷库
试题库
当前位置：
X题卡
>
所有题目
>
题目详情
Robotic Highway Cones A University of Nebraska professor has developed robotic cones and barr...
查看本题答案
包含此试题的试卷
理工类《单选集》真题及答案
点击查看
你可能感兴趣的试题
RoboticHighwayCones??AUniversityofNebraskaprofesso
—Whattimeshallweleavefortheairport?—It'sfoggytoday
whether the highway will
whether will the highway
when the highway will
when will the highway
RoboticHighwayCones AUniversityofNebraskaprofes
why
where
when
what
RoboticHighwayCones AUniversityofNebraskaprofes
employ
observe
remove
instruct
RoboticHighwayCones AUniversityofNebraskaprofes
benefit
protect
learn
inspire
Technologyismakinglifeeasierforsomedairyfarmers.Th
Whatistrueofroboticdrivers?
It will take some time before robotic drivers can be put to practical use．
Robotic drivers are not allowed to drive on busy roads．
Robotic drivers can never replace human drivers．
Robotic drivers are too expensive to use．
RoboticHighwayCones AUniversityofNebraskaprofes
proceeds
functions
finishes
improves
RoboticHighwayCones AUniversityofNebraskaprofes
applied
asked
called
argued
RoboticHighwayCones AUniversityofNebraskaprofes
helpful
beautiful
small
huge
SchoolsofroboticfishcouldbesentintotheThamestoprod
RoboticHighwayCones AUniversityofNebraskaprofes
idea
report
demand
fund
RoboticHighwayCones AUniversityofNebraskaprofes
saving
marketing
moving
devising
RoboticHighwayCones AUniversityofNebraskaprofes
at
on
in
with
RoboticHighwayCones AUniversityofNebraskaprofes
clean
important
entire
original
RoboticHighwayCones AUniversityofNebraskaprofes
If
While
Since
Because
RoboticHighwayCones AUniversityofNebraskaprofes
Kindly
Normally
Greatly
Strangely
RoboticHighwayConesAUniversityofNebraskaprofessorh
RoboticHighwayCones AUniversityofNebraskaprofes
block
cut
set
turn
RoboticHighwayCones AUniversityofNebraskaprofes
work
place
order
action
热门试题
更多
ADHDLinkedtoAirPollutants Childrenhaveanincreasedofattentionproblemsseenasearlyasgradeschool.Iftheirnosesinhaled吸入acertaintypeofairpollutionwhentheywerepregnant.That’sthefindingofanewstudy.Releasedwhenthingsaren’tburnedcompletelythispollutionisknownaspolycyclicaromatichydrocarbonsorPAHs.ThebiggestsourcesofthesePAHs:theburningoffossilfuelswoodandtrash. FredericaPereraworksatColumbiaUniversity’sMailmanSchoolofPublicHealthisNewYorkCity.Sheresearcheshowexposuretothingsintheenvironmentaffectschildren’shealthinanewstudysheandherteamstudiedtheexposuretoairpollutionof233nonsmokingpregnantwomeninNewYorkCity.Becauseburningtobaccocanspew排放PAHsintotheairandlungsPerera’steamfocusedonnonsmokers.Theresearcherswantedtoprobe探查othersourcesofPAHsonesthat’swouldhavebeenhardforanindividualtoavoid. Theteamstartedbytestingthebloodofeachwomanduringpregnancy.ThereasonAnyPAHsinawoman’sbloodwouldalsobeavailabletothebabyinherwomb.Nineyearslatertheresearchersinvestigatedsignsofattentionproblemsinthosechildrennowage9.Theyaskedeachchild’smotheraseriesofquestions.Theseincludedwhateverherchildhadproblemsdoingthingsthatneededsustained长期的mentaleffortsuchashomeworkorgameswithfriends.Thescientistsalsoaskedifthekidshadtroublefollowinginstructionsormadefrequentcarelessmistakes.AllofthesecanbesymptomsofadisordercalledAttentionDeficitHyperactivityDisorderorADHD.AboutoneinU.S.childrenhasADHD. AmongthewomenstudiedtrafficandhomeheatingweretheprimarysourcesofairpollutionexposurePereraandherteamsuspect.SomeofthesewomenhadlowlevelsofPAHsintheirblood.Ohtershadhighlevels.Thosewithhighlevelswerefivetimesaslikelytohavechildrenwhoshowedattentionproblemsbyage9.ThenewfindingswerepublishedNovember5inthejournalPLOSONE. NonsmokingmotherswereselectedbecausetheeffectofsmokingonPAHswasunclear.
{{*HTML*}}{{B}}第三篇{{/B}} ??????? ??????????? ??{{B}}UndergroundCoalFires--aLoomingCatastrophe{{/B}}? ?CoalburningdeepundergroundinChinaIndiaandIndonesiaisthreatening theenvironmentandhumanlifescientistshavewarned.Theselarge-scale undergroundblazescausethegroundtemperaturetoheatupandkillsurrounding vegetationproducegreenhousegasesandcanevenigniteforestfiresapanel ofscientiststoldtheannualmeetingoftheAmericanAssociationforthe AdvancementofScienceinDenver.Theresultingreleaseofpoisonouselements likearsenicandmercurycanalsopollutelocalwatersourcesandsoilsthey warned.??CoalfiresareaglobalcatastrophesaidAssociate ProfessorGlennStracherofEastGeorgiaCollegeinSwainsboroUSA.But surprisinglyfewpeopleknowaboutthem.??Coalcanheatuponits ownandeventuallycatchfireandburnifthereisacontinuousoxygensupply. Theheatproducedisnotcausedtodisappearandundertherightcombinationsof sunlightandoxygencantriggerspontaneouscatchingfireandburning.Thiscan occurundergroundincoalstockpilesabandonedminesorevenascoalis transported.SuchfiresinChinaconsumeupto200milliontonesofcoalper yeardelegatesweretold.IncomparisontheU.S.economyconsumesaboutone billiontonesofcoalannuallysaidStracherwhoseanalysisofthelikely impactofcoalfireshasbeenacceptedforpublicationintheInternational JournalofCoalEcology.Onceunderwaycoalfirescanbumfordecadeseven centuries.Intheprocesstheyreleaselargevolumesofgreenhousegases poisonousfumesandblackparticlesintotheatmosphere.??The membersofthepaneldiscussedtheimpactthesefiresmaybehavingonglobal andregionalclimatechangeandagreedthattheundergroundnatureofthefires makesthemdifficulttodetect.OneofthemembersofthepanelAssistant ProfessorPaulVanDijkoftheInternationalInstituteforGeo-Information ScienceandEarthObservationintheNetherlandshasbeenworkingwiththe Chinesegovernmenttodetectandmonitorfiresinthenorthernregionsofthe country.??Ultimatelytheremotesensingandothertechniques shouldallowscientiststoestimatehowmuchcarbondioxidethesefiresare emitting.OnesuggestedmethodofcontainingthefireswaspresentedbyGary ColaizzioftheengineeringfirmGoodsonwhichhasdevelopedaheat-resistant groutathinmortarusedtofillcracksandcreviceswhichisdesignedtobe pumpedintothecoalfiretocutofftheoxygen supply.WhatdidStracheranalyzeinhisarticlepublishedintheInternationalJournalofCoalEcology?
{{*HTML*}}阅读下面的短文文章中有5处空白文章后面有6组文字请根据文章的内容选择5组文字将其分别放回文章原有位置以恢复文章原貌 ?????????? ??????????? ???{{B}}WatchingMicrocurrentsFlow{{/B}}??Wecan nowwatchelectricityasitflowsthrougheventhetiniestcircuits.Byscanning themagneticfieldgeneratedaselectriccurrentsflowthroughobjects physicistshavemanaged{{U}}?46?{{/U}}.Thetechnologywillallow manufacturerstoscanmicrochipsforfaultsaswellasrevealingmicroscopic defectsinanythingfromaircrafttobanknotes.??GangXiaoand BenSchragatBrownUniversityinProvidenceRhodeIslandvisualizethe currentbymeasuringsubtlechangesinthemagneticfieldofanobjectand {{U}}?47?{{/U}}??Theirsensorisadaptedfroman existingpieceoftechnologythatisusedtomeasurelargemagneticfieldsin computerharddrives.Weredesignedthemagneticsensortomakeitcapableof measuringveryweakchangesinmagneticfieldssaysXiao.??The resultingdeviceiscapableofdetectingacurrentasweakas10microamperes evenwhenthewireisburieddeepwithinachipanditshowsupfeaturesas smallas40nanometersacross.??Atpresentengineerslookingfor defectsinachiphavetopeeloffthelayersandexaminethecircuitsvisually; thisisoneoftheobstacles{{U}}?48?{{/U}}.Butthenewmagnetic microscopeissensitiveenoughtolookinsidechipsandrevealfaultssuchas shortcircuitsnicksinthewiresorelectromigration--whereadenseareaof currentpicksupsurroundingatomsandmovesthemalong.Itislikewatchinga riverflowexplainsXiao.??Aswellasscanningtinycircuits themicroscopecanbeusedtorevealtheinternalstructureofanyobject capableofconductingelectricity.Forexampleitcouldlookdirectlyat microscopiccracksinanaeroplane’sfuselage{{U}}?49?{{/U}}.The techniquecannotyetpickupelectricalactivityinthehumanbrainbecausethe currentthereistoosmallbutXiaodoesn’truleitoutinthefuture.Ican neversayneverhesays.??Althoughtheresearchershaveonly justmadethetechnicaldetailsofthemicroscopepublicitisalreadyonsale fromelectronicscompanyMicroMagneticsinFallRiverMassachusetts.Itis currentlythesizeofarefrigeratorandtakesseveralminutestoscana circuitbutXiaoandSchragareworking{{U}}?50?{{/U}}.A.to shrinkittothesizeofadesktopcomputerandcutthescanningtimeto30 secondsB.tomakingchipsanysmallerC.totaketinychipswe requireD.topicturetheprogressofthecurrentsE.convertingthe informationintoacolorpictureshowingthedensityofcurrentateach pointF.faultsinthemetalstripofaforgedbanknoteorbacteriaina watersample
Therewasasimultaneoustrialtakingplaceinthenextbuilding.
Theseproductsareinferiortothosewebroughtlastyear.
{{*HTML*}}阅读下面的短文文章中有5处空白文章后面有6组文字请根据文章的内容选择5组文字将其分别放回文章原有位置以恢复文章原貌 ?????????? ??????????? ???{{B}}WatchingMicrocurrentsFlow{{/B}}??Wecan nowwatchelectricityasitflowsthrougheventhetiniestcircuits.Byscanning themagneticfieldgeneratedaselectriccurrentsflowthroughobjects physicistshavemanaged{{U}}?46?{{/U}}.Thetechnologywillallow manufacturerstoscanmicrochipsforfaultsaswellasrevealingmicroscopic defectsinanythingfromaircrafttobanknotes.??GangXiaoand BenSchragatBrownUniversityinProvidenceRhodeIslandvisualizethe currentbymeasuringsubtlechangesinthemagneticfieldofanobjectand {{U}}?47?{{/U}}??Theirsensorisadaptedfroman existingpieceoftechnologythatisusedtomeasurelargemagneticfieldsin computerharddrives.Weredesignedthemagneticsensortomakeitcapableof measuringveryweakchangesinmagneticfieldssaysXiao.??The resultingdeviceiscapableofdetectingacurrentasweakas10microamperes evenwhenthewireisburieddeepwithinachipanditshowsupfeaturesas smallas40nanometersacross.??Atpresentengineerslookingfor defectsinachiphavetopeeloffthelayersandexaminethecircuitsvisually; thisisoneoftheobstacles{{U}}?48?{{/U}}.Butthenewmagnetic microscopeissensitiveenoughtolookinsidechipsandrevealfaultssuchas shortcircuitsnicksinthewiresorelectromigration--whereadenseareaof currentpicksupsurroundingatomsandmovesthemalong.Itislikewatchinga riverflowexplainsXiao.??Aswellasscanningtinycircuits themicroscopecanbeusedtorevealtheinternalstructureofanyobject capableofconductingelectricity.Forexampleitcouldlookdirectlyat microscopiccracksinanaeroplane’sfuselage{{U}}?49?{{/U}}.The techniquecannotyetpickupelectricalactivityinthehumanbrainbecausethe currentthereistoosmallbutXiaodoesn’truleitoutinthefuture.Ican neversayneverhesays.??Althoughtheresearchershaveonly justmadethetechnicaldetailsofthemicroscopepublicitisalreadyonsale fromelectronicscompanyMicroMagneticsinFallRiverMassachusetts.Itis currentlythesizeofarefrigeratorandtakesseveralminutestoscana circuitbutXiaoandSchragareworking{{U}}?50?{{/U}}.A.to shrinkittothesizeofadesktopcomputerandcutthescanningtimeto30 secondsB.tomakingchipsanysmallerC.totaketinychipswe requireD.topicturetheprogressofthecurrentsE.convertingthe informationintoacolorpictureshowingthedensityofcurrentateach pointF.faultsinthemetalstripofaforgedbanknoteorbacteriaina watersample
ADHDLinkedtoAirPollutants Childrenhaveanincreasedofattentionproblemsseenasearlyasgradeschool.Iftheirnosesinhaled吸入acertaintypeofairpollutionwhentheywerepregnant.That’sthefindingofanewstudy.Releasedwhenthingsaren’tburnedcompletelythispollutionisknownaspolycyclicaromatichydrocarbonsorPAHs.ThebiggestsourcesofthesePAHs:theburningoffossilfuelswoodandtrash. FredericaPereraworksatColumbiaUniversity’sMailmanSchoolofPublicHealthisNewYorkCity.Sheresearcheshowexposuretothingsintheenvironmentaffectschildren’shealthinanewstudysheandherteamstudiedtheexposuretoairpollutionof233nonsmokingpregnantwomeninNewYorkCity.Becauseburningtobaccocanspew排放PAHsintotheairandlungsPerera’steamfocusedonnonsmokers.Theresearcherswantedtoprobe探查othersourcesofPAHsonesthat’swouldhavebeenhardforanindividualtoavoid. Theteamstartedbytestingthebloodofeachwomanduringpregnancy.ThereasonAnyPAHsinawoman’sbloodwouldalsobeavailabletothebabyinherwomb.Nineyearslatertheresearchersinvestigatedsignsofattentionproblemsinthosechildrennowage9.Theyaskedeachchild’smotheraseriesofquestions.Theseincludedwhateverherchildhadproblemsdoingthingsthatneededsustained长期的mentaleffortsuchashomeworkorgameswithfriends.Thescientistsalsoaskedifthekidshadtroublefollowinginstructionsormadefrequentcarelessmistakes.AllofthesecanbesymptomsofadisordercalledAttentionDeficitHyperactivityDisorderorADHD.AboutoneinU.S.childrenhasADHD. AmongthewomenstudiedtrafficandhomeheatingweretheprimarysourcesofairpollutionexposurePereraandherteamsuspect.SomeofthesewomenhadlowlevelsofPAHsintheirblood.Ohtershadhighlevels.Thosewithhighlevelswerefivetimesaslikelytohavechildrenwhoshowedattentionproblemsbyage9.ThenewfindingswerepublishedNovember5inthejournalPLOSONE. TrafficandhomeheatingwereconsideredtobethebiggestsourcesofPAHsforthesubjectsintheresearch.
Hesaidsomeharshwordsabouthisbrother.
{{*HTML*}}阅读下面的短文文中有15处空白每处空白给出了4个选项请根据短文的内容从4个选项中选择1个最佳答案 ??????? ??????????? ?????{{B}}ABiologicalClock{{/B}}? ?Everylivingthinghaswhatscientistscallabiologicalclockthat controlsbehavior.Thebiologicalclocktells{{U}}?51?{{/U}}whento formflowersandwhentheflowersshouldopen.Ittells{{U}}?52?{{/U}} whentoleavetheprotectivecocoonsandflyawayandittellsanimalsand humanbeingswhentoeatsleepandwake.??Eventsoutsidethe plantandanimal{{U}}?53?{{/U}}theactionsofsomebiologicalclocks. Scientistsrecentlyfoundforexamplethatatinyanimalchangesthecolorof itsfur{{U}}?54?{{/U}}thenumberofhoursofdaylight.Intheshort {{U}}?55?{{/U}}ofwinteritsfurbecomeswhite.Thefurbecomesgray brownincolorinthelongerhoursofdaylightinsummer.??Inner signalscontrolotherbiologicalclocks.Germanscientistsfoundthatsomekind ofinternalclockseemstoorderbirdstobegintheirlongmigration {{U}}?56?{{/U}}twiceeachyear.Birds{{U}}?57?{{/U}}flying becomerestlesswhenitistimeforthetrip{{U}}?58?{{/U}}they becomecalmagainwhenthetimeoftheflighthasended.? ?Scientistssaytheyarebeginningtolearnwhich{{U}}?59?{{/U}} ofthebraincontainbiologicalclocks.AnAmericanresearcherMartinMoorhead saidasmallgroupofcellsnearthefrontofthebrain{{U}}?60?{{/U}} tocontrolthetimingofsomeofouractions.These{{U}}?61?{{/U}} tellapersonwhento{{U}}?62?{{/U}}whentosleepandwhentoseek food.Scientistssaythereprobablyareotherbiologicalclockcellsthat controlotherbodyactivities.??Dr.Moorheadisstudying {{U}}?63?{{/U}}ourbiologicalclocksaffectthewaywedoourwork. Forexamplemostofushavegreatdifficultyifwemustoftenchangeto differentworkhours.??{{U}}?64?{{/U}}cantakemany daysforahumanbodytoacceptthemajorchangeinworkhours.Dr.Moorhead saidindustrialofficialsshouldhaveabetterunderstandingofbiological clocksandhowtheyaffectworkers.Hesaid{{U}}?65?{{/U}} understandingcouldcutsicknessandaccidentsatworkandwouldhelpincreasea factory’sproduction.
{{*HTML*}}下面有3篇短文每篇短文后有5道题每题后面有4个选项请仔细阅读短文并根据短文回答其后面的问题从4个选项中选择1个最佳答案{{B}}第一篇{{/B}} ??????? ??????????? ????{{B}}Snowflakes{{/B}}??You’veprobably heardthatnotwosnowflakesarealike.Ofcoursenobodyhaseverconfirmed thatstatementbyexaminingeveryoneoftheestimatedoneseptillionsnowflakes thatdrifttoEartheachyear.StillKennethLibbrechtaprofessoratthe CaliforniaInstituteofTechnologyisconfidentthatthestatementis true.??Snowflakesaren’tflakysaysLibbrecht.Attheirbasic levelthey’recrystalline.Thelatticeofeverysnowflakeissix-sidedin shape.Thesimplestsnowcrystalsaresix-sidedflatplatesandsix-sided columns.Suchcrystalsarecommoninplaceswheretheairisextremelycoldand dry.Snowcrystalsacquiretheirspecialbeautywhentheirsimplesix-sided symmetryblossoms.Undertherightconditionseachofthesixcomersofa crystalsproutswhatiscalledanarm.Inamatterofminutesthearmscan becomehighlyornateandgivethecrystalastarlikeappearance.? ?Severalfactorsintheenvironmentaffecttheshapeandgrowthrateofa snowcrystal.Onefactorishumidity.Crystalsgrowfasterandinmoreintricate shapeashumidityincreases.Asecondfactorisairtemperature.Asnowflakeis bornwhenseveralmoleculesofwatervaporinacloudlandonaspeckofdust andfreezetoformasimplecrystal.Astheyoungcrystalbopsaroundinthe clouditpassesthroughairpocketsofvaryingtemperatures.Ifthecrystal passesthroughapocketofairthatissay-15degreesCelsiusitwillgrow quicklyandsproutsixarmssaysLibbrecht.Ifthecrystalisthentossedinto awarmerpocketoneabout-10℃thearms’tipswillstopgrowingquicklyand formsix-sidedplates.Ifthecrystalthendriftsintoanevenwarmerpocketof about-5℃itstopandbottomwillgrowmorequicklythanitssidesandbecome morecolumnlikeinshape.??Inthecourseofitslifespana snow-crystalmightflutterthroughmanywarmerandcolderpocketsacquiringa complicatedanduniquegrowthhistory.Suchahistorywillgiverisetoa snowflakethatisunlikeanyother.Eacharmonthesnowflakewilllookexactly likeeveryotheronebutthecrystalitselfwillbeoneofakind.? ?UsinghiscoolingtanksLibbrechthaslearnedhowtocreatesnowcrystals ofdifferentshapes--platescolumnsneedlesetc.Libbrechthasevenrefined histechniquessothathecanmakecrystalsthatlookhighlysimilartoone another.Stillhelacksthecontroltomanufactureidenticaltwinsnowflakes.A slightdifferenceinhumidityandtemperaturecanupsetthegrowthprofileofa crystal.Libbrechtisnotableto
Iwillnottoleratethatsortofbehaviorinmyclass.
{{*HTML*}}{{B}}第二篇{{/B}} ??????? ????????{{B}}PoweringaCity?It’s aBreeze.{{/B}}??Thegracefulwoodenwindmillsthathavebrokenup theflatDutchlandscapeforcenturies--anationalsymbollikewoodenshoes andtulips--yieldedlongagotoungainlymetal-poleturbines.? ?Nowwindmillsarebreakingintoanewfrontier.Thoughstillinits teethingstagestheurbanturbineisahigh-techwindmilldesignedto generateenergyfromtherooftopsofbusycities.Lighterquieterandoften moreefficientthanruralcounterpartstheytakeadvantageoftheextreme turbulenceandrapidshiftsindirectionthatcharacterizeurbanwind patterns.??Prototypeshavebeensuccessfullytestedinseveral DutchcitiesandthecitygovernmentintheHaguehasrecentlyagreedtobegin alarge-scaledeploymentin2003.?CurrentmodelscostUS＄8000toUS ＄12000andcangeneratebetween3000and7000kilowatthoursofelectricity peryear.AtypicalDutchhouseholduses3500kilowatthoursperyearwhilein theUnitedStatesthisfigurejumpstoaround10000kilowatthours.? ?Butsofartheyarebeingdesignedmoreforpublicorcommercial buildingsthanforprivatehomes.Thesmallestofthecurrentmodelsweigh roughly200kilogramsandcanbeinstalledonaroofinafewhourswithout usingacrane.??GermanyFinlandandDenmarkhavealsobeen experimentingwiththetechnologybuttheever-practicalDutcharenatural pioneersinurbanwindpowermainlybecauseofthelackofspace.The Netherlandswith16millionpeoplecrowdedintoacountrytwicethesizeof SloveniaisthemostdenselypopulatedinEurope.??Problems remainhoweverforexamplepublicsafetyconcernsandsostrictstandards shouldbeappliedtoanypotentialmanufacturers.Vibrationsarethemain probleminskyscraper-highturbine.Peopledon’tknowwhatitwouldbeliketo workthereinanofficenexttooneofthebigturbines.Itmightbetoo hectic.??Meanwhileprojectsareunderwaytouseminimillsto generatepowerforlifeboatsstreetlightsandportablegenerators.Ithink thethingaboutwindpoweristhatyoucanuseitinawholerangeof situationssaidCorinMillaisoftheEuropeanWindEnergyAssociation.It’s averylocaltechnologyandyoucanuseitrightinyourbackyard.Idon’t thinkanybodywantsanuclearpowerplantintheir backyard.Whichstatementbestdescribestheurbanturbinementionedinthesecondparagraph?
{{*HTML*}}阅读下面的短文文中有15处空白每处空白给出了4个选项请根据短文的内容从4个选项中选择1个最佳答案 ??????? ??????????? ?????{{B}}ABiologicalClock{{/B}}? ?Everylivingthinghaswhatscientistscallabiologicalclockthat controlsbehavior.Thebiologicalclocktells{{U}}?51?{{/U}}whento formflowersandwhentheflowersshouldopen.Ittells{{U}}?52?{{/U}} whentoleavetheprotectivecocoonsandflyawayandittellsanimalsand humanbeingswhentoeatsleepandwake.??Eventsoutsidethe plantandanimal{{U}}?53?{{/U}}theactionsofsomebiologicalclocks. Scientistsrecentlyfoundforexamplethatatinyanimalchangesthecolorof itsfur{{U}}?54?{{/U}}thenumberofhoursofdaylight.Intheshort {{U}}?55?{{/U}}ofwinteritsfurbecomeswhite.Thefurbecomesgray brownincolorinthelongerhoursofdaylightinsummer.??Inner signalscontrolotherbiologicalclocks.Germanscientistsfoundthatsomekind ofinternalclockseemstoorderbirdstobegintheirlongmigration {{U}}?56?{{/U}}twiceeachyear.Birds{{U}}?57?{{/U}}flying becomerestlesswhenitistimeforthetrip{{U}}?58?{{/U}}they becomecalmagainwhenthetimeoftheflighthasended.? ?Scientistssaytheyarebeginningtolearnwhich{{U}}?59?{{/U}} ofthebraincontainbiologicalclocks.AnAmericanresearcherMartinMoorhead saidasmallgroupofcellsnearthefrontofthebrain{{U}}?60?{{/U}} tocontrolthetimingofsomeofouractions.These{{U}}?61?{{/U}} tellapersonwhento{{U}}?62?{{/U}}whentosleepandwhentoseek food.Scientistssaythereprobablyareotherbiologicalclockcellsthat controlotherbodyactivities.??Dr.Moorheadisstudying {{U}}?63?{{/U}}ourbiologicalclocksaffectthewaywedoourwork. Forexamplemostofushavegreatdifficultyifwemustoftenchangeto differentworkhours.??{{U}}?64?{{/U}}cantakemany daysforahumanbodytoacceptthemajorchangeinworkhours.Dr.Moorhead saidindustrialofficialsshouldhaveabetterunderstandingofbiological clocksandhowtheyaffectworkers.Hesaid{{U}}?65?{{/U}} understandingcouldcutsicknessandaccidentsatworkandwouldhelpincreasea factory’sproduction.
Thedoctorsdidnotrevealthetruthtohim.
ADHDLinkedtoAirPollutants Childrenhaveanincreasedofattentionproblemsseenasearlyasgradeschool.Iftheirnosesinhaled吸入acertaintypeofairpollutionwhentheywerepregnant.That’sthefindingofanewstudy.Releasedwhenthingsaren’tburnedcompletelythispollutionisknownaspolycyclicaromatichydrocarbonsorPAHs.ThebiggestsourcesofthesePAHs:theburningoffossilfuelswoodandtrash. FredericaPereraworksatColumbiaUniversity’sMailmanSchoolofPublicHealthisNewYorkCity.Sheresearcheshowexposuretothingsintheenvironmentaffectschildren’shealthinanewstudysheandherteamstudiedtheexposuretoairpollutionof233nonsmokingpregnantwomeninNewYorkCity.Becauseburningtobaccocanspew排放PAHsintotheairandlungsPerera’steamfocusedonnonsmokers.Theresearcherswantedtoprobe探查othersourcesofPAHsonesthat’swouldhavebeenhardforanindividualtoavoid. Theteamstartedbytestingthebloodofeachwomanduringpregnancy.ThereasonAnyPAHsinawoman’sbloodwouldalsobeavailabletothebabyinherwomb.Nineyearslatertheresearchersinvestigatedsignsofattentionproblemsinthosechildrennowage9.Theyaskedeachchild’smotheraseriesofquestions.Theseincludedwhateverherchildhadproblemsdoingthingsthatneededsustained长期的mentaleffortsuchashomeworkorgameswithfriends.Thescientistsalsoaskedifthekidshadtroublefollowinginstructionsormadefrequentcarelessmistakes.AllofthesecanbesymptomsofadisordercalledAttentionDeficitHyperactivityDisorderorADHD.AboutoneinU.S.childrenhasADHD. AmongthewomenstudiedtrafficandhomeheatingweretheprimarysourcesofairpollutionexposurePereraandherteamsuspect.SomeofthesewomenhadlowlevelsofPAHsintheirblood.Ohtershadhighlevels.Thosewithhighlevelswerefivetimesaslikelytohavechildrenwhoshowedattentionproblemsbyage9.ThenewfindingswerepublishedNovember5inthejournalPLOSONE. KidswithADHDcommonlyfailinschool.
{{*HTML*}}下面有3篇短文每篇短文后有5道题每题后面有4个选项请仔细阅读短文并根据短文回答其后面的问题从4个选项中选择1个最佳答案{{B}}第一篇{{/B}} ??????? ??????????? ????{{B}}Snowflakes{{/B}}??You’veprobably heardthatnotwosnowflakesarealike.Ofcoursenobodyhaseverconfirmed thatstatementbyexaminingeveryoneoftheestimatedoneseptillionsnowflakes thatdrifttoEartheachyear.StillKennethLibbrechtaprofessoratthe CaliforniaInstituteofTechnologyisconfidentthatthestatementis true.??Snowflakesaren’tflakysaysLibbrecht.Attheirbasic levelthey’recrystalline.Thelatticeofeverysnowflakeissix-sidedin shape.Thesimplestsnowcrystalsaresix-sidedflatplatesandsix-sided columns.Suchcrystalsarecommoninplaceswheretheairisextremelycoldand dry.Snowcrystalsacquiretheirspecialbeautywhentheirsimplesix-sided symmetryblossoms.Undertherightconditionseachofthesixcomersofa crystalsproutswhatiscalledanarm.Inamatterofminutesthearmscan becomehighlyornateandgivethecrystalastarlikeappearance.? ?Severalfactorsintheenvironmentaffecttheshapeandgrowthrateofa snowcrystal.Onefactorishumidity.Crystalsgrowfasterandinmoreintricate shapeashumidityincreases.Asecondfactorisairtemperature.Asnowflakeis bornwhenseveralmoleculesofwatervaporinacloudlandonaspeckofdust andfreezetoformasimplecrystal.Astheyoungcrystalbopsaroundinthe clouditpassesthroughairpocketsofvaryingtemperatures.Ifthecrystal passesthroughapocketofairthatissay-15degreesCelsiusitwillgrow quicklyandsproutsixarmssaysLibbrecht.Ifthecrystalisthentossedinto awarmerpocketoneabout-10℃thearms’tipswillstopgrowingquicklyand formsix-sidedplates.Ifthecrystalthendriftsintoanevenwarmerpocketof about-5℃itstopandbottomwillgrowmorequicklythanitssidesandbecome morecolumnlikeinshape.??Inthecourseofitslifespana snow-crystalmightflutterthroughmanywarmerandcolderpocketsacquiringa complicatedanduniquegrowthhistory.Suchahistorywillgiverisetoa snowflakethatisunlikeanyother.Eacharmonthesnowflakewilllookexactly likeeveryotheronebutthecrystalitselfwillbeoneofakind.? ?UsinghiscoolingtanksLibbrechthaslearnedhowtocreatesnowcrystals ofdifferentshapes--platescolumnsneedlesetc.Libbrechthasevenrefined histechniquessothathecanmakecrystalsthatlookhighlysimilartoone another.Stillhelacksthecontroltomanufactureidenticaltwinsnowflakes.A slightdifferenceinhumidityandtemperaturecanupsetthegrowthprofileofa crystal.Whatarethefactorsthataffecttheshapeandgrowthrateofasnowcrystal?
{{*HTML*}}阅读下面的短文文中有15处空白每处空白给出了4个选项请根据短文的内容从4个选项中选择1个最佳答案 ??????? ??????????? ?????{{B}}ABiologicalClock{{/B}}? ?Everylivingthinghaswhatscientistscallabiologicalclockthat controlsbehavior.Thebiologicalclocktells{{U}}?51?{{/U}}whento formflowersandwhentheflowersshouldopen.Ittells{{U}}?52?{{/U}} whentoleavetheprotectivecocoonsandflyawayandittellsanimalsand humanbeingswhentoeatsleepandwake.??Eventsoutsidethe plantandanimal{{U}}?53?{{/U}}theactionsofsomebiologicalclocks. Scientistsrecentlyfoundforexamplethatatinyanimalchangesthecolorof itsfur{{U}}?54?{{/U}}thenumberofhoursofdaylight.Intheshort {{U}}?55?{{/U}}ofwinteritsfurbecomeswhite.Thefurbecomesgray brownincolorinthelongerhoursofdaylightinsummer.??Inner signalscontrolotherbiologicalclocks.Germanscientistsfoundthatsomekind ofinternalclockseemstoorderbirdstobegintheirlongmigration {{U}}?56?{{/U}}twiceeachyear.Birds{{U}}?57?{{/U}}flying becomerestlesswhenitistimeforthetrip{{U}}?58?{{/U}}they becomecalmagainwhenthetimeoftheflighthasended.? ?Scientistssaytheyarebeginningtolearnwhich{{U}}?59?{{/U}} ofthebraincontainbiologicalclocks.AnAmericanresearcherMartinMoorhead saidasmallgroupofcellsnearthefrontofthebrain{{U}}?60?{{/U}} tocontrolthetimingofsomeofouractions.These{{U}}?61?{{/U}} tellapersonwhento{{U}}?62?{{/U}}whentosleepandwhentoseek food.Scientistssaythereprobablyareotherbiologicalclockcellsthat controlotherbodyactivities.??Dr.Moorheadisstudying {{U}}?63?{{/U}}ourbiologicalclocksaffectthewaywedoourwork. Forexamplemostofushavegreatdifficultyifwemustoftenchangeto differentworkhours.??{{U}}?64?{{/U}}cantakemany daysforahumanbodytoacceptthemajorchangeinworkhours.Dr.Moorhead saidindustrialofficialsshouldhaveabetterunderstandingofbiological clocksandhowtheyaffectworkers.Hesaid{{U}}?65?{{/U}} understandingcouldcutsicknessandaccidentsatworkandwouldhelpincreasea factory’sproduction.
{{*HTML*}}阅读下面的短文文中有15处空白每处空白给出了4个选项请根据短文的内容从4个选项中选择1个最佳答案 ??????? ??????????? ?????{{B}}ABiologicalClock{{/B}}? ?Everylivingthinghaswhatscientistscallabiologicalclockthat controlsbehavior.Thebiologicalclocktells{{U}}?51?{{/U}}whento formflowersandwhentheflowersshouldopen.Ittells{{U}}?52?{{/U}} whentoleavetheprotectivecocoonsandflyawayandittellsanimalsand humanbeingswhentoeatsleepandwake.??Eventsoutsidethe plantandanimal{{U}}?53?{{/U}}theactionsofsomebiologicalclocks. Scientistsrecentlyfoundforexamplethatatinyanimalchangesthecolorof itsfur{{U}}?54?{{/U}}thenumberofhoursofdaylight.Intheshort {{U}}?55?{{/U}}ofwinteritsfurbecomeswhite.Thefurbecomesgray brownincolorinthelongerhoursofdaylightinsummer.??Inner signalscontrolotherbiologicalclocks.Germanscientistsfoundthatsomekind ofinternalclockseemstoorderbirdstobegintheirlongmigration {{U}}?56?{{/U}}twiceeachyear.Birds{{U}}?57?{{/U}}flying becomerestlesswhenitistimeforthetrip{{U}}?58?{{/U}}they becomecalmagainwhenthetimeoftheflighthasended.? ?Scientistssaytheyarebeginningtolearnwhich{{U}}?59?{{/U}} ofthebraincontainbiologicalclocks.AnAmericanresearcherMartinMoorhead saidasmallgroupofcellsnearthefrontofthebrain{{U}}?60?{{/U}} tocontrolthetimingofsomeofouractions.These{{U}}?61?{{/U}} tellapersonwhento{{U}}?62?{{/U}}whentosleepandwhentoseek food.Scientistssaythereprobablyareotherbiologicalclockcellsthat controlotherbodyactivities.??Dr.Moorheadisstudying {{U}}?63?{{/U}}ourbiologicalclocksaffectthewaywedoourwork. Forexamplemostofushavegreatdifficultyifwemustoftenchangeto differentworkhours.??{{U}}?64?{{/U}}cantakemany daysforahumanbodytoacceptthemajorchangeinworkhours.Dr.Moorhead saidindustrialofficialsshouldhaveabetterunderstandingofbiological clocksandhowtheyaffectworkers.Hesaid{{U}}?65?{{/U}} understandingcouldcutsicknessandaccidentsatworkandwouldhelpincreasea factory’sproduction.
{{*HTML*}}阅读下面的短文文中有15处空白每处空白给出了4个选项请根据短文的内容从4个选项中选择1个最佳答案 ??????? ??????????? ?????{{B}}ABiologicalClock{{/B}}? ?Everylivingthinghaswhatscientistscallabiologicalclockthat controlsbehavior.Thebiologicalclocktells{{U}}?51?{{/U}}whento formflowersandwhentheflowersshouldopen.Ittells{{U}}?52?{{/U}} whentoleavetheprotectivecocoonsandflyawayandittellsanimalsand humanbeingswhentoeatsleepandwake.??Eventsoutsidethe plantandanimal{{U}}?53?{{/U}}theactionsofsomebiologicalclocks. Scientistsrecentlyfoundforexamplethatatinyanimalchangesthecolorof itsfur{{U}}?54?{{/U}}thenumberofhoursofdaylight.Intheshort {{U}}?55?{{/U}}ofwinteritsfurbecomeswhite.Thefurbecomesgray brownincolorinthelongerhoursofdaylightinsummer.??Inner signalscontrolotherbiologicalclocks.Germanscientistsfoundthatsomekind ofinternalclockseemstoorderbirdstobegintheirlongmigration {{U}}?56?{{/U}}twiceeachyear.Birds{{U}}?57?{{/U}}flying becomerestlesswhenitistimeforthetrip{{U}}?58?{{/U}}they becomecalmagainwhenthetimeoftheflighthasended.? ?Scientistssaytheyarebeginningtolearnwhich{{U}}?59?{{/U}} ofthebraincontainbiologicalclocks.AnAmericanresearcherMartinMoorhead saidasmallgroupofcellsnearthefrontofthebrain{{U}}?60?{{/U}} tocontrolthetimingofsomeofouractions.These{{U}}?61?{{/U}} tellapersonwhento{{U}}?62?{{/U}}whentosleepandwhentoseek food.Scientistssaythereprobablyareotherbiologicalclockcellsthat controlotherbodyactivities.??Dr.Moorheadisstudying {{U}}?63?{{/U}}ourbiologicalclocksaffectthewaywedoourwork. Forexamplemostofushavegreatdifficultyifwemustoftenchangeto differentworkhours.??{{U}}?64?{{/U}}cantakemany daysforahumanbodytoacceptthemajorchangeinworkhours.Dr.Moorhead saidindustrialofficialsshouldhaveabetterunderstandingofbiological clocksandhowtheyaffectworkers.Hesaid{{U}}?65?{{/U}} understandingcouldcutsicknessandaccidentsatworkandwouldhelpincreasea factory’sproduction.
{{*HTML*}}阅读下面的短文文中有15处空白每处空白给出了4个选项请根据短文的内容从4个选项中选择1个最佳答案 ??????? ??????????? ?????{{B}}ABiologicalClock{{/B}}? ?Everylivingthinghaswhatscientistscallabiologicalclockthat controlsbehavior.Thebiologicalclocktells{{U}}?51?{{/U}}whento formflowersandwhentheflowersshouldopen.Ittells{{U}}?52?{{/U}} whentoleavetheprotectivecocoonsandflyawayandittellsanimalsand humanbeingswhentoeatsleepandwake.??Eventsoutsidethe plantandanimal{{U}}?53?{{/U}}theactionsofsomebiologicalclocks. Scientistsrecentlyfoundforexamplethatatinyanimalchangesthecolorof itsfur{{U}}?54?{{/U}}thenumberofhoursofdaylight.Intheshort {{U}}?55?{{/U}}ofwinteritsfurbecomeswhite.Thefurbecomesgray brownincolorinthelongerhoursofdaylightinsummer.??Inner signalscontrolotherbiologicalclocks.Germanscientistsfoundthatsomekind ofinternalclockseemstoorderbirdstobegintheirlongmigration {{U}}?56?{{/U}}twiceeachyear.Birds{{U}}?57?{{/U}}flying becomerestlesswhenitistimeforthetrip{{U}}?58?{{/U}}they becomecalmagainwhenthetimeoftheflighthasended.? ?Scientistssaytheyarebeginningtolearnwhich{{U}}?59?{{/U}} ofthebraincontainbiologicalclocks.AnAmericanresearcherMartinMoorhead saidasmallgroupofcellsnearthefrontofthebrain{{U}}?60?{{/U}} tocontrolthetimingofsomeofouractions.These{{U}}?61?{{/U}} tellapersonwhento{{U}}?62?{{/U}}whentosleepandwhentoseek food.Scientistssaythereprobablyareotherbiologicalclockcellsthat controlotherbodyactivities.??Dr.Moorheadisstudying {{U}}?63?{{/U}}ourbiologicalclocksaffectthewaywedoourwork. Forexamplemostofushavegreatdifficultyifwemustoftenchangeto differentworkhours.??{{U}}?64?{{/U}}cantakemany daysforahumanbodytoacceptthemajorchangeinworkhours.Dr.Moorhead saidindustrialofficialsshouldhaveabetterunderstandingofbiological clocksandhowtheyaffectworkers.Hesaid{{U}}?65?{{/U}} understandingcouldcutsicknessandaccidentsatworkandwouldhelpincreasea factory’sproduction.
{{*HTML*}}{{B}}第二篇{{/B}} ??????? ????????{{B}}PoweringaCity?It’s aBreeze.{{/B}}??Thegracefulwoodenwindmillsthathavebrokenup theflatDutchlandscapeforcenturies--anationalsymbollikewoodenshoes andtulips--yieldedlongagotoungainlymetal-poleturbines.? ?Nowwindmillsarebreakingintoanewfrontier.Thoughstillinits teethingstagestheurbanturbineisahigh-techwindmilldesignedto generateenergyfromtherooftopsofbusycities.Lighterquieterandoften moreefficientthanruralcounterpartstheytakeadvantageoftheextreme turbulenceandrapidshiftsindirectionthatcharacterizeurbanwind patterns.??Prototypeshavebeensuccessfullytestedinseveral DutchcitiesandthecitygovernmentintheHaguehasrecentlyagreedtobegin alarge-scaledeploymentin2003.?CurrentmodelscostUS＄8000toUS ＄12000andcangeneratebetween3000and7000kilowatthoursofelectricity peryear.AtypicalDutchhouseholduses3500kilowatthoursperyearwhilein theUnitedStatesthisfigurejumpstoaround10000kilowatthours.? ?Butsofartheyarebeingdesignedmoreforpublicorcommercial buildingsthanforprivatehomes.Thesmallestofthecurrentmodelsweigh roughly200kilogramsandcanbeinstalledonaroofinafewhourswithout usingacrane.??GermanyFinlandandDenmarkhavealsobeen experimentingwiththetechnologybuttheever-practicalDutcharenatural pioneersinurbanwindpowermainlybecauseofthelackofspace.The Netherlandswith16millionpeoplecrowdedintoacountrytwicethesizeof SloveniaisthemostdenselypopulatedinEurope.??Problems remainhoweverforexamplepublicsafetyconcernsandsostrictstandards shouldbeappliedtoanypotentialmanufacturers.Vibrationsarethemain probleminskyscraper-highturbine.Peopledon’tknowwhatitwouldbeliketo workthereinanofficenexttooneofthebigturbines.Itmightbetoo hectic.??Meanwhileprojectsareunderwaytouseminimillsto generatepowerforlifeboatsstreetlightsandportablegenerators.Ithink thethingaboutwindpoweristhatyoucanuseitinawholerangeof situationssaidCorinMillaisoftheEuropeanWindEnergyAssociation.It’s averylocaltechnologyandyoucanuseitrightinyourbackyard.Idon’t thinkanybodywantsanuclearpowerplantintheir backyard.Netherlandsleadsintheurbanturbinetechnologybecause
{{*HTML*}}阅读下面的短文文中有15处空白每处空白给出了4个选项请根据短文的内容从4个选项中选择1个最佳答案 ??????? ??????????? ?????{{B}}ABiologicalClock{{/B}}? ?Everylivingthinghaswhatscientistscallabiologicalclockthat controlsbehavior.Thebiologicalclocktells{{U}}?51?{{/U}}whento formflowersandwhentheflowersshouldopen.Ittells{{U}}?52?{{/U}} whentoleavetheprotectivecocoonsandflyawayandittellsanimalsand humanbeingswhentoeatsleepandwake.??Eventsoutsidethe plantandanimal{{U}}?53?{{/U}}theactionsofsomebiologicalclocks. Scientistsrecentlyfoundforexamplethatatinyanimalchangesthecolorof itsfur{{U}}?54?{{/U}}thenumberofhoursofdaylight.Intheshort {{U}}?55?{{/U}}ofwinteritsfurbecomeswhite.Thefurbecomesgray brownincolorinthelongerhoursofdaylightinsummer.??Inner signalscontrolotherbiologicalclocks.Germanscientistsfoundthatsomekind ofinternalclockseemstoorderbirdstobegintheirlongmigration {{U}}?56?{{/U}}twiceeachyear.Birds{{U}}?57?{{/U}}flying becomerestlesswhenitistimeforthetrip{{U}}?58?{{/U}}they becomecalmagainwhenthetimeoftheflighthasended.? ?Scientistssaytheyarebeginningtolearnwhich{{U}}?59?{{/U}} ofthebraincontainbiologicalclocks.AnAmericanresearcherMartinMoorhead saidasmallgroupofcellsnearthefrontofthebrain{{U}}?60?{{/U}} tocontrolthetimingofsomeofouractions.These{{U}}?61?{{/U}} tellapersonwhento{{U}}?62?{{/U}}whentosleepandwhentoseek food.Scientistssaythereprobablyareotherbiologicalclockcellsthat controlotherbodyactivities.??Dr.Moorheadisstudying {{U}}?63?{{/U}}ourbiologicalclocksaffectthewaywedoourwork. Forexamplemostofushavegreatdifficultyifwemustoftenchangeto differentworkhours.??{{U}}?64?{{/U}}cantakemany daysforahumanbodytoacceptthemajorchangeinworkhours.Dr.Moorhead saidindustrialofficialsshouldhaveabetterunderstandingofbiological clocksandhowtheyaffectworkers.Hesaid{{U}}?65?{{/U}} understandingcouldcutsicknessandaccidentsatworkandwouldhelpincreasea factory’sproduction.
{{*HTML*}}{{B}}第三篇{{/B}} ??????? ??????????? ??{{B}}UndergroundCoalFires--aLoomingCatastrophe{{/B}}? ?CoalburningdeepundergroundinChinaIndiaandIndonesiaisthreatening theenvironmentandhumanlifescientistshavewarned.Theselarge-scale undergroundblazescausethegroundtemperaturetoheatupandkillsurrounding vegetationproducegreenhousegasesandcanevenigniteforestfiresapanel ofscientiststoldtheannualmeetingoftheAmericanAssociationforthe AdvancementofScienceinDenver.Theresultingreleaseofpoisonouselements likearsenicandmercurycanalsopollutelocalwatersourcesandsoilsthey warned.??CoalfiresareaglobalcatastrophesaidAssociate ProfessorGlennStracherofEastGeorgiaCollegeinSwainsboroUSA.But surprisinglyfewpeopleknowaboutthem.??Coalcanheatuponits ownandeventuallycatchfireandburnifthereisacontinuousoxygensupply. Theheatproducedisnotcausedtodisappearandundertherightcombinationsof sunlightandoxygencantriggerspontaneouscatchingfireandburning.Thiscan occurundergroundincoalstockpilesabandonedminesorevenascoalis transported.SuchfiresinChinaconsumeupto200milliontonesofcoalper yeardelegatesweretold.IncomparisontheU.S.economyconsumesaboutone billiontonesofcoalannuallysaidStracherwhoseanalysisofthelikely impactofcoalfireshasbeenacceptedforpublicationintheInternational JournalofCoalEcology.Onceunderwaycoalfirescanbumfordecadeseven centuries.Intheprocesstheyreleaselargevolumesofgreenhousegases poisonousfumesandblackparticlesintotheatmosphere.??The membersofthepaneldiscussedtheimpactthesefiresmaybehavingonglobal andregionalclimatechangeandagreedthattheundergroundnatureofthefires makesthemdifficulttodetect.OneofthemembersofthepanelAssistant ProfessorPaulVanDijkoftheInternationalInstituteforGeo-Information ScienceandEarthObservationintheNetherlandshasbeenworkingwiththe Chinesegovernmenttodetectandmonitorfiresinthenorthernregionsofthe country.??Ultimatelytheremotesensingandothertechniques shouldallowscientiststoestimatehowmuchcarbondioxidethesefiresare emitting.OnesuggestedmethodofcontainingthefireswaspresentedbyGary ColaizzioftheengineeringfirmGoodsonwhichhasdevelopedaheat-resistant groutathinmortarusedtofillcracksandcreviceswhichisdesignedtobe pumpedintothecoalfiretocutofftheoxygen supply.Accordingtothefirstparagraphoneofthewarningsgivenbythescientistsisthat
Thelawcarriesapenaltyofuptothreeyearsinprison.
{{*HTML*}}阅读下面这篇短文短文后有2项测试任务1第23～26题要求．从所给的6个选项中为第2～5段每段选择1个正确的小标题2第27～30题要求从所给的6个选项中选择4个正确选项分别完成每个句子 ?????????? ??????????{{B}}TheMir SpaceStation{{/B}}??1?TheRussianMirSpaceStationwhich camedownin2001atlastafter15yearsofpioneeringtheconceptoflong-term humanspaceflightisrememberedforitsaccomplishmentsinthehumanspace flighthistory.Itcanbecreditedwithmanyfirstsinspace.??2 ?DuringMir’slifetimeRussiaspentaboutUS＄4.2billiontobuildand maintainthestation.??3?TheSovietUnionlaunchedMir whichwasdesignedtolastfromthreetofiveyearsonFebruary201986and housed104astronautsover12yearsandsevenmonthsmostofwhomwerenot Russian.Infactitbecamethefirstinternationalspacestationbyplaying hostto62peoplefrom11countries.From1995through1998sevenastronauts fromtheUnitedStatestookturnslivingonMirforuptosixmonthseach.They wereamongthe37Americanswhovisitedthestationduringninestopoversby spaceshuttles.??4?Themorethan400milliontheUnited StatesprovidedRussianforthevisitsnotonlykeptMiroperatingbutalso gavetheAmericansandtheirpartnersintheinternationalstationproject valuableexperienceinlong-termflightandmultinationaloperations.? ?5?AdebatecontinuesoverMir’scontributionstoscience.Duringits existenceMirwasthelaboratoryfor23000experimentsandcarriedscientific equipmentestimatedtobeworth＄80millionfrommanynations.Experimentson Mirarecreditedwitharangeoffindingsfromthefirstsolidmeasurementof therationofheavyheliumatomsinspacetohowtogrowwheatinspace.Butfor thosefavouringhumanspaceexplorationMirshowedthatpeoplecouldliveand workinspacelongenoughforatriptoMars.Thelongestsinglestayinspace isthe437.7daysthatRussianastronautValeryPolyakovspentonMirfrom1994 to1995.AndSergieAvdeyevaccumulated747.6daysinspaceinthreetripsto thespacestation.ThelongestAmericanstaywasthatofShannonLucidwho spent188daysaboardMirin1996.??6?Despitethemany firstsMiraccomplished1997wasabadyearoutof15forMir.In1997an oxygengeneratorcaughtfire.Laterthemaincomputersystembrokedown causingthestationtodriftseveraltimesandtherewerepower failures.??7?Mostoftheseproblemswererepairedwith AmericanhelpandsuppliersbutMir’sreputationasaspacestationwas ruined.??8?Mir’ssetbacksarenothingthoughwhenwe comparethemwithitsaccomplishments.Mirwasatremendoussuccesswhichwill berememberedasamilestoneinspaceexplorationandthespacestationthat showedlong-termhumanhabitationinspacewaspossible.Butit’stimetomove ontothenextgeneration.TheInternationalSpaceStationbeingbuiltwillbe betterbutitowesagreatdebttoMir.WhenwethinkofMirintermsofitsachievementsitssetbacksare?______.
ADHDLinkedtoAirPollutants Childrenhaveanincreasedofattentionproblemsseenasearlyasgradeschool.Iftheirnosesinhaled吸入acertaintypeofairpollutionwhentheywerepregnant.That’sthefindingofanewstudy.Releasedwhenthingsaren’tburnedcompletelythispollutionisknownaspolycyclicaromatichydrocarbonsorPAHs.ThebiggestsourcesofthesePAHs:theburningoffossilfuelswoodandtrash. FredericaPereraworksatColumbiaUniversity’sMailmanSchoolofPublicHealthisNewYorkCity.Sheresearcheshowexposuretothingsintheenvironmentaffectschildren’shealthinanewstudysheandherteamstudiedtheexposuretoairpollutionof233nonsmokingpregnantwomeninNewYorkCity.Becauseburningtobaccocanspew排放PAHsintotheairandlungsPerera’steamfocusedonnonsmokers.Theresearcherswantedtoprobe探查othersourcesofPAHsonesthat’swouldhavebeenhardforanindividualtoavoid. Theteamstartedbytestingthebloodofeachwomanduringpregnancy.ThereasonAnyPAHsinawoman’sbloodwouldalsobeavailabletothebabyinherwomb.Nineyearslatertheresearchersinvestigatedsignsofattentionproblemsinthosechildrennowage9.Theyaskedeachchild’smotheraseriesofquestions.Theseincludedwhateverherchildhadproblemsdoingthingsthatneededsustained长期的mentaleffortsuchashomeworkorgameswithfriends.Thescientistsalsoaskedifthekidshadtroublefollowinginstructionsormadefrequentcarelessmistakes.AllofthesecanbesymptomsofadisordercalledAttentionDeficitHyperactivityDisorderorADHD.AboutoneinU.S.childrenhasADHD. AmongthewomenstudiedtrafficandhomeheatingweretheprimarysourcesofairpollutionexposurePereraandherteamsuspect.SomeofthesewomenhadlowlevelsofPAHsintheirblood.Ohtershadhighlevels.Thosewithhighlevelswerefivetimesaslikelytohavechildrenwhoshowedattentionproblemsbyage9.ThenewfindingswerepublishedNovember5inthejournalPLOSONE. PereraandherteamchosenonsmokingpregnantwomenalloverAmerica.
Mostpeoplefindrejectionhardtoaccept.
{{*HTML*}}下面有3篇短文每篇短文后有5道题每题后面有4个选项请仔细阅读短文并根据短文回答其后面的问题从4个选项中选择1个最佳答案{{B}}第一篇{{/B}} ??????? ??????????? ????{{B}}Snowflakes{{/B}}??You’veprobably heardthatnotwosnowflakesarealike.Ofcoursenobodyhaseverconfirmed thatstatementbyexaminingeveryoneoftheestimatedoneseptillionsnowflakes thatdrifttoEartheachyear.StillKennethLibbrechtaprofessoratthe CaliforniaInstituteofTechnologyisconfidentthatthestatementis true.??Snowflakesaren’tflakysaysLibbrecht.Attheirbasic levelthey’recrystalline.Thelatticeofeverysnowflakeissix-sidedin shape.Thesimplestsnowcrystalsaresix-sidedflatplatesandsix-sided columns.Suchcrystalsarecommoninplaceswheretheairisextremelycoldand dry.Snowcrystalsacquiretheirspecialbeautywhentheirsimplesix-sided symmetryblossoms.Undertherightconditionseachofthesixcomersofa crystalsproutswhatiscalledanarm.Inamatterofminutesthearmscan becomehighlyornateandgivethecrystalastarlikeappearance.? ?Severalfactorsintheenvironmentaffecttheshapeandgrowthrateofa snowcrystal.Onefactorishumidity.Crystalsgrowfasterandinmoreintricate shapeashumidityincreases.Asecondfactorisairtemperature.Asnowflakeis bornwhenseveralmoleculesofwatervaporinacloudlandonaspeckofdust andfreezetoformasimplecrystal.Astheyoungcrystalbopsaroundinthe clouditpassesthroughairpocketsofvaryingtemperatures.Ifthecrystal passesthroughapocketofairthatissay-15degreesCelsiusitwillgrow quicklyandsproutsixarmssaysLibbrecht.Ifthecrystalisthentossedinto awarmerpocketoneabout-10℃thearms’tipswillstopgrowingquicklyand formsix-sidedplates.Ifthecrystalthendriftsintoanevenwarmerpocketof about-5℃itstopandbottomwillgrowmorequicklythanitssidesandbecome morecolumnlikeinshape.??Inthecourseofitslifespana snow-crystalmightflutterthroughmanywarmerandcolderpocketsacquiringa complicatedanduniquegrowthhistory.Suchahistorywillgiverisetoa snowflakethatisunlikeanyother.Eacharmonthesnowflakewilllookexactly likeeveryotheronebutthecrystalitselfwillbeoneofakind.? ?UsinghiscoolingtanksLibbrechthaslearnedhowtocreatesnowcrystals ofdifferentshapes--platescolumnsneedlesetc.Libbrechthasevenrefined histechniquessothathecanmakecrystalsthatlookhighlysimilartoone another.Stillhelacksthecontroltomanufactureidenticaltwinsnowflakes.A slightdifferenceinhumidityandtemperaturecanupsetthegrowthprofileofa crystal.WhatdoesProfessorLibbrechtbelievetobetrue?
{{*HTML*}}阅读下面的短文文中有15处空白每处空白给出了4个选项请根据短文的内容从4个选项中选择1个最佳答案 ??????? ??????????? ?????{{B}}ABiologicalClock{{/B}}? ?Everylivingthinghaswhatscientistscallabiologicalclockthat controlsbehavior.Thebiologicalclocktells{{U}}?51?{{/U}}whento formflowersandwhentheflowersshouldopen.Ittells{{U}}?52?{{/U}} whentoleavetheprotectivecocoonsandflyawayandittellsanimalsand humanbeingswhentoeatsleepandwake.??Eventsoutsidethe plantandanimal{{U}}?53?{{/U}}theactionsofsomebiologicalclocks. Scientistsrecentlyfoundforexamplethatatinyanimalchangesthecolorof itsfur{{U}}?54?{{/U}}thenumberofhoursofdaylight.Intheshort {{U}}?55?{{/U}}ofwinteritsfurbecomeswhite.Thefurbecomesgray brownincolorinthelongerhoursofdaylightinsummer.??Inner signalscontrolotherbiologicalclocks.Germanscientistsfoundthatsomekind ofinternalclockseemstoorderbirdstobegintheirlongmigration {{U}}?56?{{/U}}twiceeachyear.Birds{{U}}?57?{{/U}}flying becomerestlesswhenitistimeforthetrip{{U}}?58?{{/U}}they becomecalmagainwhenthetimeoftheflighthasended.? ?Scientistssaytheyarebeginningtolearnwhich{{U}}?59?{{/U}} ofthebraincontainbiologicalclocks.AnAmericanresearcherMartinMoorhead saidasmallgroupofcellsnearthefrontofthebrain{{U}}?60?{{/U}} tocontrolthetimingofsomeofouractions.These{{U}}?61?{{/U}} tellapersonwhento{{U}}?62?{{/U}}whentosleepandwhentoseek food.Scientistssaythereprobablyareotherbiologicalclockcellsthat controlotherbodyactivities.??Dr.Moorheadisstudying {{U}}?63?{{/U}}ourbiologicalclocksaffectthewaywedoourwork. Forexamplemostofushavegreatdifficultyifwemustoftenchangeto differentworkhours.??{{U}}?64?{{/U}}cantakemany daysforahumanbodytoacceptthemajorchangeinworkhours.Dr.Moorhead saidindustrialofficialsshouldhaveabetterunderstandingofbiological clocksandhowtheyaffectworkers.Hesaid{{U}}?65?{{/U}} understandingcouldcutsicknessandaccidentsatworkandwouldhelpincreasea factory’sproduction.
{{*HTML*}}{{B}}第三篇{{/B}} ??????? ??????????? ??{{B}}UndergroundCoalFires--aLoomingCatastrophe{{/B}}? ?CoalburningdeepundergroundinChinaIndiaandIndonesiaisthreatening theenvironmentandhumanlifescientistshavewarned.Theselarge-scale undergroundblazescausethegroundtemperaturetoheatupandkillsurrounding vegetationproducegreenhousegasesandcanevenigniteforestfiresapanel ofscientiststoldtheannualmeetingoftheAmericanAssociationforthe AdvancementofScienceinDenver.Theresultingreleaseofpoisonouselements likearsenicandmercurycanalsopollutelocalwatersourcesandsoilsthey warned.??CoalfiresareaglobalcatastrophesaidAssociate ProfessorGlennStracherofEastGeorgiaCollegeinSwainsboroUSA.But surprisinglyfewpeopleknowaboutthem.??Coalcanheatuponits ownandeventuallycatchfireandburnifthereisacontinuousoxygensupply. Theheatproducedisnotcausedtodisappearandundertherightcombinationsof sunlightandoxygencantriggerspontaneouscatchingfireandburning.Thiscan occurundergroundincoalstockpilesabandonedminesorevenascoalis transported.SuchfiresinChinaconsumeupto200milliontonesofcoalper yeardelegatesweretold.IncomparisontheU.S.economyconsumesaboutone billiontonesofcoalannuallysaidStracherwhoseanalysisofthelikely impactofcoalfireshasbeenacceptedforpublicationintheInternational JournalofCoalEcology.Onceunderwaycoalfirescanbumfordecadeseven centuries.Intheprocesstheyreleaselargevolumesofgreenhousegases poisonousfumesandblackparticlesintotheatmosphere.??The membersofthepaneldiscussedtheimpactthesefiresmaybehavingonglobal andregionalclimatechangeandagreedthattheundergroundnatureofthefires makesthemdifficulttodetect.OneofthemembersofthepanelAssistant ProfessorPaulVanDijkoftheInternationalInstituteforGeo-Information ScienceandEarthObservationintheNetherlandshasbeenworkingwiththe Chinesegovernmenttodetectandmonitorfiresinthenorthernregionsofthe country.??Ultimatelytheremotesensingandothertechniques shouldallowscientiststoestimatehowmuchcarbondioxidethesefiresare emitting.OnesuggestedmethodofcontainingthefireswaspresentedbyGary ColaizzioftheengineeringfirmGoodsonwhichhasdevelopedaheat-resistant groutathinmortarusedtofillcracksandcreviceswhichisdesignedtobe pumpedintothecoalfiretocutofftheoxygen supply.Accordingtothefifthparagraphwhatisthesuggestedmethodtocontrolundergroundfires?
热门题库
更多
中石油职称英语
理工类
卫生类
综合类
国际货运代理师
报关水平测试
报检员
物流员(四级)
助理物流师(三级)
物流师(二级)
高级物流师(一级)
物流案例分析
单证员基础理论与知识
单证员缮制与操作
国际货运代理理论与实务
外贸综合业务
湘公网安备 43130202000226号