简介：Ingasturbineengines,laminar-turbulenttransitionoccurs.However,generally,theturbulencemodelstodescribesuchtransitionresultsintooearlyandtooshorttransition.Combiningaturbulencemodelwithadescriptionofintermittency,i.e.thefractionoftimetheflowisturbulentduringthetransitionphase,canimproveit.Bylettinggrowtheintermittencyfromzerotounity,startandevolutionoftransitioncanbeimposed.Inthispaper,amethodwhereadynamicequationofintermittencycombiningwithatwo-equationk-ωturbulencemodelisdescribed.Thisintermittencyfactorisapremultiplicatoroftheturbulentviscositycomputedbytheturbulencemodel.FollowingasuggestionbyMenteretal.[1],thestartoftransitioniscomputedbasedonlocalvariables.

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简介：《K文件》这本有占奇怪的左图右文的书，是一群有点奇怪的K客玩出来的，K客是一群艺术玩家，他们几乎无所不玩，无所不玩而后快，他们提出的口号是：一、用自己的玩法去玩。二、人人都是艺术家。然后，他们使用PS、鼠标笔、某种奇怪的文字，各种随手物件和一个开窍的大脑，开始去K。

简介：Inthisstudy,weattempttheanalysisofthepassageflowinthecentrifugalimpellerusingFEMwith/withouttheturbulencemodel,andcomparethisresultwiththeexperimentalresult.TheturbulencemodelisthelowReynoldsk-εmodelproposedbyChien.WeusetheGSMACmethodfortheReynoldsaveragedNavier-Stokesequations,theEulerexplicitmethodforthetransportequationsoftheturbulentkineticenergyandthedissipationrate.AllequationsarediscretizedbytheGalerkin'smethod.Atthemidpassageofthecentrifugalimpeller,thepassagewisevelocitycomponenttendstoincreaseinthepressure-to-suctiondirection,andtheothercomponenttowardthepressuresurfacetendstobelargeintheregionofthemiddleblade-to-bladetothehubside.Thetipleakagesappeararoundtheregionofthemiddleblade-to-bladenearthecasingtogetherwiththesecondaryflowtowardthesuctionsurface.Thesephenomenacorrespondwiththeexperimentalresult,qualitatively.

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简介：In2010,theBESCollaboration[1]foundaclearenhancementintheK0K0massdistributionintheJ=ψ!ηK0K0decay.SuchanenhancementisusuallyasignatureofanL=0resonancearoundthreshold,whichinthiscasewouldcorrespondstoanh1statewithquantumnumbersIG(JPC)=0??(1+??).Thish1statewaspredictedbytheChiralUnitarytheoryintheKKinteraction.Becauseoftheconversationlaw,thisstatecanonlydecaytoK0K0channel,andcanbestudiedefficientlyintheJ=ψ!ηK0K0decay.

简介：Mixedalcoholisofgreatpromiseasoctaneimproverinautomotivefuel,andhopefultoreplacetheMTBEtoreducetheenvironmentalpollution,Inthisfield,alkali-promtedmolybdenum-basedcatalystshavebeengivenspecialinterestbecauseoftheirexcellentsulfur-toleranceforsynthesisofmixedalcoholfromCO+H2,Itwasreportedthatthecoblatisafavorablepromoterforenhancingalcoholproduction,especiallyforimprovingtheselectivityforC2+alcohol[1-3],moreover,stronginteractionbetweenConandMoisinfavorofmixedalcoholsynthesis[4].Recently,weprparedakindofK-Co-Moultrafineparticlesbysol-gelmethodanditshowsmuchsmallerparticlesizebuthigheractivtyandselectivitytowardalcoholformationthantheonepreparedbyconventionalmethod[5],TheaimofthepresentworkistoresearchthemicostructuresoftheMoandCospeciesintheK-Co-Mosamplespreparedbydifferentmethod.

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简介：Thenextgenerationofadvancedlightsourcesrequiresphotonswithlargeaveragefluxandhighbrightness,whichneedsadvancedelectrongunmatchedwithexcellentphotocathodematerials.K2CsSbphotocathodehastheadvantagesofhighquantumefficiency,longlifetimeandinstantaneousresponse.ThisstudyintroducesthedesignofasetofK2CsSbphotocathodepreparationsystemsanddetailedpreparationprocessofK2CsSbphotocathodes,includingsequentialdepositionprocessandco-depositionprocess,andfinallydevelopsaK2CsSbphotocathode.Theinfluenceoflaserpoweronthequantumefficiencyisalsoinvestigated.

简介：Thebaryonspectrumandthebaryoncouplingsaretwoofthemostimportantissuesinhadronicphysicsandtheyareattractingmuchattention.Bothontheexperimentalandtheoreticalsides,thenucleonexcitedstatesbelow2.0GeVhavebeenextensivelystudied[1].However,thecurrentinformationforthepropertiesofstatesaroundorabove2.0GeVisscarce.Ontheotherhand,inthisenergyregion,manytheoreticalapproacheshavepredictedmissingNstates,whichhavenotbeensofarobserved.Hence,thestudyofthepossibleroleplayedbythe2.0GeVregionnucleonresonancesintheavailableaccuratedataistimelyandcouldshedlightintothecomplicateddynamicsthatgovernsthehighexcitednucleonspectrum.

简介：Westudythegeneralrepresentationsofpositivepartialtranspose(PPT)statesinCKCMCN.ForthePPTstateswithrank-Nacanonicalformisobtained,fromwhichasufficientseparabilityconditionispresented.

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简介：Inordertodeepentheunderstandingoftherelationshipbetweenfundamentalproperties（including:microstructureandcomposition）andphotocatalyticperformance,fourbismuthatecompounds,including:LiBiO3,NaBiO3,KBiO3,andAgBiO3,areregardedasresearchexamplesinthepresentwork,becausetheyhaveparticularcrystalstructuresandsimilarcompositions.Usingdensityfunctionaltheorycalculations,theirstructural,electronic,andopticalpropertiesareinvestigatedandcomparedsystematically.Firstofall,thecalculatedresultsofcrystalstructuresandopticalpropertiesareinagreementwithavailablepublishedexperimentaldata.Basedonthecalculatedresults,itisfoundthatthetunneledorlayeredmicro-structuralpropertiesleadtothestrongerinteractionbetweenbismuthandoxygen,andtheweakerinteractionbetweenalkaline-earthmetaland[BiO6]octahedron,resultinginthefeatureofmulti-bandgapsinthecasesofLiBiO3,NaBiO3,andKBiO3.ThisconclusionissupportedbythecaseofAgBiO3,inwhichthefeatureofmulti-bandgapsdisappears,duetothestrongerinteractionbetweenthenoblemetaland[BiO6]octahedron.Thesepropertieshavesignificantadvantagesinthephotocatalyticperformance:absorbinglowenergyphotons,rapidlytransferringenergycarriers.Furthermore,thefeaturesofelectronicstructuresofbismuthatecompoundsarewellreflectedbytheabsorptionspectra,whichcouldbeconfirmedbyexperimentalmeasurementsinpractice.Combinedwiththecalculatedresults,itcouldbeconsideredthatthecrystalstructuresandcompositionsofthephotocatalystdeterminetheelectronicstructuresandopticalproperties,andsubsequentlydeterminethecorrespondingphotocatalyticperformance.Thus,anovelBi-basedphotocatalystdrivenbyvisible-lightcouldbedesignedbyutilizingspecificcompositionstoformfavorableelectronicstructuresorspecificmicro-structurestoformabeneficialchannelforenergycarriers.

简介：我们学习了物质，研究了物质的有关属性．那么，自然界的物质结构又是怎样的呢？由于物质内部的结构无法用肉眼观察，我们应该用什么方法来探究物质内部的微观结构呢？

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简介：ThispaperdevelopsamodifiedTaitequationofstate(EOS)fortrans-decahydronaphthalenewithfourparametersA,B,V0andP0beingtreatedaslinearfunctionsoftemperature.Thecoefficientscontainedinthesefunctionsaredeterminedthroughfittingtheexperimentalcompressiondataintheliteraturebetween293Kand446Kandatpressuresfrom10to200MPa.Expressionsforthethermalexpansivity,isothermalcompressibilityandthermodynamicquantitiesarededucedandthenumericalresultsareanalyticallyderived.ThenumericalresultsshowthattheprecisionofthemodifiedTaitEOSdevelopedinthispaperissuperiortotheEOSintheliterature.