2012年职称英语等级考试用书(理工类)b2012新增部分

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1、第三+八篇"LifeFormFound"onSaturrTsTitanScientistssaytheyhavediscoveredhintsofalienlife1ontheSaturn'smoon2・ThediscoveryofasortoflifewasannouncedafterresearchersattheUSspaceagency’NASA^analyzeddatafromspacecraftCassini4,whichpointedtoztheexistenceofmethane-basedfor

2、moflifeonSaturn'sbiggestmoon.Scientistshavereportedlydiscoveredcluesshowingprimitivealienbeingsare"breathing”inTitan'sdenseatmospherefilledwithhydrogen・TheyarguethathydrogengetsabsorbedbeforehittingTitan'splanet-likesurfacecoveredwithmethanelakesandrivers・Thi

3、sztheysay,pointstotheexisteneeofsome"bugsn5consumingthehydrogenatthesurfaceofthemoonlessthanhalfthesizeoftheEarth."Wesuggestedhydrogenconsumptionbecauseit'stheobviousgasforlifetoconsumeonTitan,similartothewayweconsumeoxygenonEarth,"saysNASAscientistChrisMcKay

4、."Ifthesesignsdoturnouttobeasignoflifejtwouldbedoublyexcitingbecauseitwouldrepresentasecondformoflifeindependentfromwater-basedlifeonEarth."Todate,scientistshavenotyetdetectedthisformoflifeanywhere,thoughthereareliquid-water-basedmicroorganismsonEarththatgrow

5、wellonmethaneorproduceitasawasteproduct・OnTitan,wheretemperaturesarearound90Kelvin^minus290degreesFarenheit）,amethanebasedorganismwouldhavetouseasubstancethatisliquidasitsmediumforlivingprocesses,butnotwateritself・WaterisfrozensolidonTitan'ssurfaceandmuchtooc

6、oldtosupportlifeasweknowit.ScientistshadexpectedtheSun'sinteractionswithchemicalsintheatmospheretoproduceacoatingofacetyleneonTitan'ssurface・ButCassinidetectednoacetyleneonthesurface・TheabsenceofdetectableacetyleneontheTitan*ssurfacecanverywellhaveanon-biolog

7、icalexplanation,saidMarkAllen,aprincipalinvestigator7oftheNASATitanteam."Scientificconservatismsuggeststhatabiologicalexplanationshouldbethelastchoiceafterallnon・biologicalexplanationsareaddressed/'Allensaid・"Wehavealotofworktodotoruleout8possiblenon・biologic

8、alexplanations・Itismorelikelythatachemicalprocesszwithoutbiology,canexplaintheseresults."词汇：Saturn/'saeton/n.土星methane/'mi^ein/n.甲烷,j召气Titan/'taiten/n.土卫六acetylene/e'setilkn/n.乙块alien/'ei