组合焊缝的试件与角焊缝试件的区别是前者试件()。

A、管壁较厚
B、板太厚
C、开带角度坡口、有利于焊透
D、开I形坡口
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Ifyoucomparethequalityofourgoodwiththatofothercountry,youwillseeourpriceisveryreasonable.

Shonaneedstodofurtherresearchinorderto____.

A、presentthegovernmentwithherfindings
B、decidethelevelofextrafundingneeded
C、identifythepreferencesofthepublic

1.AEuropeanspacecrafttookofftodaytospearheadthesearchforanother"Earth"amongthestars.

2.TheCorotspacetelescopeblastedoffaboardaRussianSoyuzrocketfromtheBaikonurcosmodromeinKazakhstanshortlyafter2.20pm.

3.Corot,shortforconvectionrotationandplanetarytransits,isthefirstinstrumentcapableoffindingsmallrockyplanetsbeyondthesolarsystem.Anysuchplanetsituatedintherightorbitstandsagoodchanceofhavingliquidwateronitssurface,andquitepossiblylife,althoughaleadingscientistinvolvedintheprojectsaiditwasunlikelytofind"anylittlegreenmen".

4.DevelopedbytheFrenchspaceagency,CNES,andpartneredbytheEuropeanSpaceAgency(ESA),Austria,Belgium,Germany,BrazilandSpain,Corotwillmonitoraround120,000starswithits27cmtelescopefromapolarorbit514milesabovetheEarth.Overtwoandahalfyears,itwillfocusonfivetosixdifferentareasofthesky,measuringthebrightnessofabout10,000starsevery512seconds.

5."Atthepresentmomentwearehopingtofindoutmoreaboutthenatureofplanetsaroundstarswhicharepotentialhabitats.Wearelookingathabitableplanets,notinhabitedplanets.Wearenotgoingtofindanylittlegreenmen,"ProfessorIanRoxburgh,anESAscientistwhohasbeeninvolvedwithCorotsinceitsinception,toldtheBBCRadio4Todayprogramme.

6.ProfRoxburghsaiditwashopedCorotwouldfind"rockyplanetsthatcoulddevelopanatmosphereand,iftheyaretherightdistancefromtheirparentstar,theycouldhavewater".

7.Tosearchforplanets,thetelescopewilllookforthedimmingofstarlightcausedwhenanobjectpassesinfrontofastar,knownasa"transit".Althoughitwilltakemoresophisticatedspacetelescopesplannedinthenext10yearstoconfirmthepresenceofanEarth-likeplanetwithoxygenandliquidwater,Corotwillletscientistsknowwheretopointtheirlenses.

8.MeasurementsofminutechangesinbrightnesswillenablescientiststodetectgiantJupiter-likegasplanetsaswellassmallrockyones.Itistherockyplanets-thatcouldbenobiggerthanabouttwicethesizeoftheEarth-whichwillcausethemostexcitement.Scientistsexpecttofindbetween10and40ofthesesmallerplanets.

9.Corotwillalsoprobeintostellarinteriorsbystudyingtheacousticwavesthatrippleacrossthesurfaceofstars,atechniquecalled"asteroseismology".

10.Thenatureoftheripplesallowsastronomerstocalculateastar’sprecisemass,ageandchemicalcomposition.

11."Aplanetpassinginfrontofastarcanbedetectedbythefallinlightfromthatstar.Smalloscillationsofthestaralsoproducechangesinthelightemitted,whichrevealwhatthestarismadeofandhowtheyarestructuredinternally.Thisdatawillprovideamajorboosttoourunderstandingofhowstarsformandevolve,"ProfRoxburghsaid.

12.Sincethediscoveryin1995ofthefirst"exoplanet"-aplanetorbitingastarotherthantheSun-morethan200othershavebeenfoundbyground-basedobservatories.

13.Untilnowtheusualmethodoffindingexoplanetshasbeentodetectthe"wobble"theirgravityimpartsonparentstars.ButonlygiantgaseousplanetsbiggerthanJupitercanbefoundthisway,andtheyareunlikelytoharbourlife.

14.Inthe2010s,ESAplanstolaunchDarwin,afleetoffourorfiveinterlinkedspacetelescopesthatwillnotonlyspotsmallrockyplanets,butanalysetheiratmospheresforsignsofbiologicalactivity.

15.Ataroundthesametime,theUSspaceagency,Nasa,willlaunchTerrestrialPlanetFinder,anotherspacetelescopedesignedtolocateEarth-likeplanets.

ChoosetheappropriateletterfromA-Dforquestion1.

1.Corotisaninstrumentwhich

(A)canhelptosearchforcertainplanets

(B)isusedtofindplanetsintheorbit

(C)canlocateplanetswithhumanbeings

(D)canspotanyplanetswithwater.

Dothefollowingstatementsagreewiththeinformationgiveninthereadingpassage?Forquestions2-5write

TRUEifthestatementagreeswiththeinformation

FALSEifthestatementcontraictstheinformation

NOTGIVENifthereisnoinformationonthisinthepassage

2.Scientistsaretryingtofindoutabouttheplanetsthatcanbeinhabited.

3.BBCRadio4recentlyfocusesonthebroadcastingofCorot.

4.Passingobjectsmightcauseafallinlight.

5.CorotcantellwhetherthereisanotherEarth-likeplanet.

Basedonyourreadingofthepassage,completethesentencesbelowwithwordstakenfromthepassage.UseNOMORETHANTHREEWORDSforeachanswer.

Withmeasurements,scientistswillbeabletosearchforsomegaseousandrockyplanets.Theywillbeextremelyexcitediftheycandiscoversomesmall6.__________,theexpectednumberofwhichcouldbeupto7.__________.

Corotwillenablescientiststostudythe8.__________ofstars.Inthisway,astar’smass,ageandchemicalcompositioncanbecalculated.

AccordingtoProfRoxburgh,changesinlightcanbecausedbypassingplanetsorstar9.__________.Therelatedstatisticscangainusabetter10.__________ofthestarformationandevolvement.

Observatorieshavefoundmanyexoplanets,whichare11.__________otherstarsthantheSun.Thecommonwayusedinfindingexoplanetscanonlydetecthugegasplanets,whichdonot12.___________.

WiththelaunchingofDarwin,astronomerswillbeabletoanalysewhetherthoserockyplanetshave13.__________forlife.

Thespeakersuggestsostrichfarmsareprofitablebecause____

A、littleinitialoutlayisrequired
B、farmedbirdsareveryproductive
C、thereisagoodmarketforthemeat

Whatisnotthemeetingprocess?

A、Introduction
B、Discussed
C、Information
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