江蘇高考科技說明文匯編

1、江蘇高中英語【科技說明文】真題匯編江蘇高中英語【科技說明文】真題匯編AIfadiversurfacestooquicklyhemaysufferthebends.Nitrogen(氮)dissolved(溶解)inhisbloodissuddenlyliberatedbythereductionofpressure.Theconsequenceifthebubbles(氣泡)accumulateinajointissharppainab

2、entbody—thusthename.Ifthebubblesfminhislungshisbraintheconsequencecanbedeath.Otherairbreathinganimalsalsosufferthisdecompression(減壓)sicknessiftheysurfacetoofast:whalesfexample.solongagodidichthyosaurs.Thattheseancientsea

3、animalsgotthebendscanbeseenfromtheirbones.Ifbubblesofnitrogenfminsidethebonetheycancutoffitsbloodsupply.Thiskillsthecellsintheboneconsequentlyweakensitsometimestothepointofcollapse.Fossil(化石)bonesthathavecavedinonthemsel

4、vesarethusasignthattheanimaloncehadthebends.BruceRothschildoftheUniversityofKansasknewallthiswhenhebeganastudyofichthyosaurbonestofindouthowwidespreadtheproblemwasinthepast.Whatheparticularlywantedtoinvestigatewashowicht

5、hyosaursadaptedtotheproblemofdecompressionoverthe150millionyears.Tothisendhehiscolleaguestraveledthewld’snaturalhistymuseumslookingathundredsofichthyosaursfromtheTriassicperiodfromthelaterJurassicCretaceousperiods.Whenhe

6、startedheassumedthatsignsofthebendswouldberarerinyoungerfossilsreflectingtheirgradualevolutionofmeasurestodealwithdecompression.Insteadhewasastonishedtodiscovertheopposite.Methan15%ofJurassicCretaceousichthyosaurshadsuff

7、eredthebendsbefetheydiedbutnotasingleTriassicspecimen(標(biāo)本)showedevidenceofthatstofinjury.Ifichthyosaursdidevolveanantidecompressionmeanstheyclearlydidsoquickly—moststrangelytheylostitafterwards.ButthatisnotwhatDrRothschil

8、dthinkshappened.Hesuspectsitwasevolutioninotheranimalsthatcausedthechange.Whalesthatsufferthebendsoftendosobecausetheyhavesurfacedtoescapeapredat(捕食動物)suchasalargeshark.OneofthefeaturesofJurassicoceanswasanabundanceoflar

9、gesharkscrocodilesbothofwhichwerefondofichthyosaurlunches.Triassicoceansbytodate:shiningnearinfraredlight(NIR近紅外線)onthedruginthecapsule.Theideaofusinglighttoliberatethedruginthecapsuleisn’tnew.Researchersaroundtheglobeha

10、vedevelopedpolymers(聚合物)othermaterialsthatbegintobreakdownwhentheyabsbeitherultraviolet(UV紫外線)visiblelight.ButtissuesalsoreadilyabsbUVvisiblelightwhichmeansthedrugreleasecanbetriggeredonlyneartheskinwherethelightcanreach

11、thecapsule.NIRlightlargelypassesthroughtissuessoresearchershavetriedtouseitasatrigger.Butfewcompounds(化合物)absbNIRwellgothroughchemicalchanges.ThatchangedlastyearwhenAdahAlmutairiachemistattheUniversityofCalifniaSiegorept

12、edthatshehercolleagueshaddesignedapolymerthatbreaksdownwhenitabsbsNIRlight.TheirpolymerusedacommerciallyavailableNIRabsbinggroupcalledonitrobenzyl(ONB).WhentheycatchthelightONBgroupsfalloffthepolymerleadingtoitsbreakdown

13、.ButONBisonlyasosoNIRabsberitcouldbepoisonoustocellswhenitseparatesfromthepolymer.SoAlmutairihercolleaguesreptedcreatinganewmaterialfcapsulesthat’sevenbetter.Thisoneconsistsofalongchainofcompoundscalledcresolgroupslinked

14、inapolymer.Cresolcontainsreactive(易反應(yīng)的)componentsthatmakeithighlyunstableinitspolymericfmafeatureAlmutairihercolleaguesusetotheiradvantage.Afterpolymerizingthecresolstheycapeachreactivecomponentwithalightabsbingcompoundc

15、alledBhc.WhentheBhcsabsbNIRlightthereactivegroupsareexposedbreakthelongpolymerintotwoshtchains.Shiningadditionallightcontinuesthisbreakdownpotentiallyreleasinganydrugsinthecapsule.What’smeAlmutairisaysBhcis10timesbettera

16、tabsbingNIRthanisONBisnotpoisonoustocells.63.AccdingtothepassagewhichofthefollowingcouldbethebesttriggerA.Temperaturechange.B.NIRlight.C.Aciditychange.D.UVlight.64.WhyisONBunsatisfactyA.ItbreaksdownwhenitabsbsNIRlight.B.