英语长篇阅读文章.docx

英语长篇阅读文章.docx

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英语长篇阅读文章

英语长篇阅读文章

　　对于语言学习者而言,阅读是语言输入的重要方式。

阅读策略是语言学习者为了提高阅读理解而采取的技巧和方法。

下面是小编带来的英语长篇阅读文章，欢迎阅读!

　　英语长篇阅读文章1

　　科技与自然

　　Technologythatimitatesnature

　　Biomimetics:

Engineersareincreasinglytakingaleafoutofnaturesbookwhenlookingforsolutionstodesignproblems

　　AFTERtakinghisdogforawalkonedayintheearly1940s,GeorgedeMestral,aSwissinventor,becamecuriousabouttheseedsoftheburdockplantthathadattachedthemselvestohisclothesandtothedogsfur.Underamicroscope,helookedcloselyatthehook-and-loopsystemthattheseedshaveevolvedtohitchhikeonpassinganimalsandaidpollination,andherealisedthatthesameapproachcouldbeusedtojoinotherthingstogether.TheresultwasVelcraproductthatwasarguablymorethanthreebillionyearsinthemaking,sincethatishowlongthenaturalmechanismthatinspiredittooktoevolve.

　　Velcroisprobablythemostfamousandcertainlythemostsuccessfulexampleofbiologicalmimicry,orbiomimetics.Infieldsfromroboticstomaterialsscience,technologistsareincreasinglyborrowingideasfromnature,andwithgoodreason:

naturesdesignshave,bydefinition,stoodthetestoftime,soitwouldbefoolishtoignorethem.Yettransplantingnaturaldesignsintoman-madetechnologiesisstillahit-or-missaffair.

　　Engineersdependonbiologiststodiscoverinterestingmechanismsforthemtoexploit,saysJulianVincent,thedirectoroftheCentreforBiomimeticandNaturalTechnologiesattheUniversityofBathinEngland.Soheandhiscolleagueshavebeenworkingonaschemetoenableengineerstobypassthebiologistsandtapintonaturesingenuitydirectly,viaadatabaseofbiologicalpatents.Theideaisthatthisdatabasewillletanyonesearchthroughawiderangeofbiologicalmechanismsandpropertiestofindnaturalsolutionstotechnologicalproblems.

　　Hownottoreinventthewheel

　　Surelyhumanintellect,andthedeliberateapplicationofdesignknowledge,candevisebettermechanismsthanthemindless,randomprocessofevolution?

Farfromit.Overbillionsofyearsoftrialanderror,naturehasdevisedeffectivesolutionstoallsortsofcomplicatedreal-worldproblems.Taketheslipperytaskofcontrollingasubmersiblevehicle,forexample.Usingpropellers,itisincrediblydifficulttomakerefinedmovements.ButNektonResearch,acompanybasedinDurham,NorthCarolina,hasdevelopedarobotfishcalledMadeleinethatmanoeuvresusingfinsinstead.

　　Insomecases,engineerscanspenddecadesinventingandperfectinganewtechnology,onlytodiscoverthatnaturebeatthemtoit.TheVenusflowerbasket,forexample,akindofdeep-seasponge,hasspinyskeletaloutgrowthsthatareremarkablysimilar,bothinappearanceandopticalproperties,tocommercialopticalfibres,notesJoannaAizenberg,aresearcheratLucentTechnologysBellLaboratoriesinNewJersey.Andsometimesthesystemsfoundinnaturecanmakeeventhemostadvancedtechnologieslookprimitivebycomparison,shesays.

　　Theskeletonsofbrittlestars,whichareseacreaturesrelatedtostarfishandseaurchins,containthousandsoftinylensesthatcollectivelyformasingle,distributedeye.Thisenablesbrittlestarstoescapepredatorsanddistinguishbetweennightandday.Besideshavingunusualopticalpropertiesandbeingverysmalleachisjustone-twentiethofamillimetreindiameterthelenseshaveanothertrickofparticularrelevancetomicro-opticalsystems.Althoughthelensesarefixedinshape,theyareconnectedviaanetworkoffluid-filledchannels,containingalight-absorbingpigment.Thecreaturecanvarythecontrastofthelensesbycontrollingthisfluid.Thesameideacanbeappliedinman-madelenses,saysDrAizenberg.Thesearemadefromsiliconandsocannotchangetheirproperties,shesays.Butbycopyingthebrittlestarsfluidicsystem,shehasbeenabletomakebiomimeticlensarrayswiththesameflexibility.

　　Anotherdemonstrationofthepowerofbiomimeticscomesfromthegecko.Thislizardsabilitytowalkupwallsandalongceilingsisofmuchinterest,andnotonlytofansofSpider-Man.Twogroupsofresearchers,oneledbyAndreGeimatManchesterUniversityandtheotherbyRonFearingattheUniversityofCalifornia,Berkeley,haveindependentlydevelopedwaystocopythegeckosabilitytoclingtowalls.Thesecretofthegeckossuccessliesinthetinyhair-likestructures,calledsetae,thatcoveritsfeet.Insteadofsecretingastickysubstance,asyoumightexpect,theyowetheiradhesivepropertiestoincrediblyweakintermolecularattractiveforces.ThesevanderWaalsforces,astheyareknown,whichexistbetweenanytwoadjacentobjects,arisebetweenthesetaeandthewalltowhichthegeckoisclinging.Normallysuchforcesarenegligible,butthesetae,withtheirspatula-liketips,maximisethesurfaceareaincontactwiththewall.Theweakforces,multipliedacrossthousandsofsetae,arethensufficienttoholdthelizardsweight.

　　BoththeBritishandAmericanteamshaveshownthattheintricatedesignofthesemicroscopicsetaecanbereproducedusingsyntheticmaterials.DrGeimcallstheresultgeckotape.Thetechnologyisstillsomeyearsawayfromcommercialisation,saysThomasKennyofStanfordUniversity,whoisamemberofDrFearingsgroup.Butwhenitdoesreachthemarket,ratherthanbeingusedtomakewall-crawlinggloves,itwillprobablybeusedasanalternativetoVelcro,orinstickingplasters.Indeed,saysDrKenny,itcouldbeparticularlyusefulinmedicalapplicationswherechemicaladhesivescannotbeused.

　　Whileitisfarfromobviousthatgeckosfeetcouldinspireanewkindofstickingplaster,therearesomefieldssuchasroboticsinwhichborrowingdesignsfromnatureisself-evidentlythesensiblethingtodo.ThenextgenerationofplanetaryexplorationvehiclesbeingdesignedbyAmericasspaceagency,NASA,forexample,willhavelegsratherthanwheels.Thatisbecauselegscangetyouplacesthatwheelscannot,saysDrKenny.Wheelsworkwellonflatsurfaces,butaremuchlessefficientonuneventerrain.ScientistsatNASAsAmesResearchCentreinMountainView,California,areevaluatinganeight-leggedwalkingrobotmodelledonascorpion,andAmericasDefenceAdvancedResearchProjectsAgency（DARPA）isfundingresearchintofour-leggedrobotdogs,withaviewtoapplyingthetechnologyonthebattlefield.

　　Havinglegsisonlyhalfthestoryitshowyoucontrolthemthatcounts,saysJosephAyers,abiologistandneurophysiologistatNortheasternUniversity,Massachusetts.Hehasspentrecentyearsdevelopingabiomimeticroboticlobsterthatdoesnotjustlooklikealobsterbutactuallyemulatespartsofalobstersnervoussystemtocontrolitswalkingbehaviour.Thecontrolsystemofthescorpionrobot,whichisbeingdevelopedbyNASAinconjunctionwiththeUniversityofBremeninGermany,isalsobiologicallyinspired.Meanwhile,aFinnishtechnologyfirm,Plustech,hasdevelopedasix-leggedtractorforuseinforestry.Clamberingoverfallenlogsandupsteephills,itcancrossterrainthatwouldbeimpassableinawheeledvehicle.

　　Otherexamplesofbiomimeticsabound:

Autotype,amaterialsfirm,hasdevelopedaplasticfilmbasedonthecomplexmicrostructuresfoundinmotheyes,whichhaveevolvedtocollectasmuchlightaspossiblewithoutreflection.Whenappliedtothescreenofamobilephone,thefilmreducesreflectionsandimprovesreadability,andimprovesbatterylifesincethereislessneedtoilluminatethescreen.ResearchersattheUniversityofFlorida,meanwhile,havedevisedacoatinginspiredbytherough,bristlyskinofsharks.Itcanbeappliedtothehullsofshipsandsubmarinestopreventalgaeandbarnaclesfromattachingthemselves.AtPennStateUniversity,engineershavedesignedaircraftwingsthatcanchangeshapeindifferentphasesofflight,justasbirdswingsdo.AndDrVincenthasdevisedasmartfabric,inspiredbythewayinwhichpineconesopenandclosedependingonthehumidity,thatcouldbeusedtomakeclothingthatadjuststochangingbodytemperaturesandkeepsthewearercool.

　　Fromhit-and-misstopoint-and-click

　　Yetdespiteallthesesuccesses,biomimeticsstilldependsfartooheavilyonserendipity,saysDrVincent.Heestimatesthatthereisonlya10%overlapbetweenbiologicalandtechnologicalmechanismsusedtosolveparticularproblems.Inotherwords,thereisstillanenormousnumberofpotentiallyusefulmechanismsthathaveyettobeexploited.Theproblemisthattheengineerslookingforsolutionsdependonbiologistshavingalreadyfoundthemandthetwogroupsmoveindifferentcirclesandspeakverydifferentlanguages.Anaturalmechanismorpropertymustfirstbediscoveredbybiologists,describedintechnologicalterms,andthenpickedupbyanengineerwhorecognisesitspotential.

　　Thisprocessisentirelythewrongwayround,saysDrVincent.Tobeeffective,biomimeticsshouldbeprovidingexamplesofsuitabletechnologiesfrombiologywhichfulfiltherequirementsofaparticularengineeringproblem,heexplains.Thatiswhyheandhiscolleagues,withfundingfromBritainsEngineeringandPhysicalSciencesResearchCouncil,havespentthepastthreeyearsbuildingadatabaseofbiologicaltrickswhichengineerswillbeabletoaccesstofindnaturalsolutionstotheirdesignproblems.Asearchofthedatabasewiththekeywordpropulsion,forexample,producesarangeofpropulsionmechanismsusedbyjellyfish,frogsandcrustaceans.

　　ThedatabasecanalsobequeriedusingatechniquedevelopedinRussia,knownasthetheoryofinventiveproblemsolving,orTRIZ.Inessence,thisisasetofrulesthatbreaksdownaproblemintosmallerparts,andthosepartsintoparticularfunctionsthatmustbeperformedb