简介:Crackopeningdisplacement(COD)wasappliedtocharacterizethefractureinitiationofthetoughhighdensitypolyethylene.Normalsinglesidenotchedthree-pointbendspecimensandsilicarubberreplicatechniqueswereusedtostudythecharacteristicCODofhigh-densitypolyethylenepipeanditsbutt-fusionjointsincludingtheweldfusionzoneandheataffectedzoneatdifferenttemperaturefrom-78℃to20℃.TestingresultsshowthatthecharacteristicCODappearstodependonthestructuralfeaturesthataredeterminedbyweldingprocessandthetestingtemperature.Asthetemperatureislowered,thecharacteristicCODofallzonesstudieddecreases.Becausetheweldingprocesssignificantlychangessomestructuralfeatureofthematerial,characteristicCODoftheweldfusionzoneisthesmallestoneamongthoseofthethreezones.TheresultscanbeusedfortheengineeringdesignandfailureanalysisofHDPEpipe.
简介:Waveguidesuperlattices,aspecialtypeofwaveguidearrays,canbedesignedtoachieveverylowcrosstalkatsubmicrometer/subwavelengthpitches.Thetheoreticalframeworkanddesignrationalesforsuchwaveguidesuperlatticeswillbepresentedindepth.Waveguidesidewallroughnesscanhelptodeterthecoherentcouplingbetweenidenticalwaveguidesinnearbysupercells,butitalsoinducesrandomfluctuationoftransmission.Statisticalbehaviorofthetransmissionduetoroughnessinawaveguidesuperlatticeissystematicallytreated.Complextransmissioncharacteristicsduetospectraloscillationandrandomroughnesswillbepresented,andtheirevolutionwiththesuperlatticelengthwillbeanalyzed.
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简介:Ahigh-density,high-fluxcirculatingfluidizedbed(CFB)riser(100mminIDand10.614minheight)wasappliedinawiderangeofoperatingconditions(withsolidfluxesupto400kg/m2sandsuperficialgasvelocitiesupto12m/s)toexamineitsradialnon-uniformitydynamics.Thesolidsholdupwasdeterminedthroughtheuseofafiber-opticprobeat11axiallevels.Theresultsindicatedthatunderalloperatingconditions,thehighsuperficialgasvelocityandlowsolidfluxesmaintainedalowradialnon-uniformityindex(RNI).Thehigh-density/fluxCFBriserhadseveraluniquecharacteristics,sothatthepeakoftheradialsolidsholdupprofileoccurredatapositionwithr/R=0.8.TheRNIandsolidsholdupatthecross-sectionalpositionhadagoodlogarithmicrelationshipatthelow-densitycondition(withameansolidsholdupof<0.2),andtheRNIdecreasedwhenthemeansolidsholdupexceeded0.2.InvestigationofthedynamicsofstratifiedinjectionrevealedthatthefeedratiohadanimportanteffectonGsandonsolidsholdupdistribution.Anovel"<"shapedaxialsolidsholdupprofilewasfound.Gsdecreasedsharplywhentheup-flowfeedratioexceeded0.5,andRNIwaslowestwhentheup-flowfeedratiowas1.
简介:BackgroundThisstudytestedthehypothesisthatmoderatealcoholintakeexertsitscardioprotectiveeffectmainlythroughanincreaseintheserumlevelofhigh-densitylipoproteincholesterol.MethodsandResultsIntheCohortofNorway(CONOR)study,149729adultparticipants,recruitedfrom1994to2003,werefollowedbylinkagetotheCauseofDeathRegistryuntil2006.Atrecruitment,questionnairedataonalcoholintakewerecollected,andtheconcentrationofhigh-densitylipoproteincholesterolinserumwasmeasured.UsingCoxregression,wefoundthattheadjustedhazardratioformenfordyingfromcoronaryheartdiseasewas0.52(95%confidenceinterval,0.39-0.69)whenconsumingalcoholmorethanonceaweekcomparedwithneverorrarely.Theratiochangedonlyslightly,to0.55(0.41-0.73),aftertheregressionmodelincludedtheserumlevelofhigh-densitycholesterol.Forwomen,thecorrespondinghazardratioswere0.62(0.32-1.23)and0.68(0.34-1.34),respectively.ConclusionsAlcoholintakeisrelatedtoareducedriskofdeathfromcoronaryheartdiseaseinthefollow-upofalarge,population-basedNorwegiancohortstudywithextensivecontrolforconfoundingfactors.Ourfindingssuggestthattheserumlevelofhigh-densitycholesterolisnotanimportantintermediatevariableinthepossiblecausalpathwaybetweenmoderatealcoholintakeandcoronaryheartdisease.
简介:ThephotoluminescencepropertiesofBiTaO4∶Pr3+andBiTaO4atroomtemperaturewerestudied,andtheinfraredtransmissionanddiffusionreflectionspectraofBiTaO4weremeasured.ThephotoluminescencespectrumofBiTaO4peaksatabout420,440and465nm.Therehasanobviousexcitationbandfrom330to370nm.ThephotoluminescencespectrumofBiTaO4∶Pr3+consistsofthecharacteristicemissionofPr3+,anditsmainpeakisat606nmfrom3P0→3H6transitionofPr3+.Itsexcitationspectrumconsistsofthewidebandwithmaximumat325nm,thewidebandintherangeof375~430nm,andthecharacteristicexcitationofPr3+.Thebandsat325nmand375~430nmmaybefromtheabsorptionofthechargetransfertransitionofthetantalategroupanddefectenergylevelsinitsforbiddenband,respectively.ThereisenergytransferfromhosttoPr3+.BecauseboththehostdensityandphotoluminescencepeakintensityofBiTaO4∶Pr3+aresuperiortoPbWO4,BiTaO4∶Pr3+maybeapotentialheavyscintillator.
简介:锌(Zn)缺乏是限制米饭庄稼生长和产量的主要土壤限制,然而,忍耐机制的基因控制仍然糟糕被理解。这里,我们介绍了有希望的loci和候选人基因交谈忍耐给Zn缺乏并且通过协会分析识别了用一365?在多样的aus(半野的类型米饭)的K单个核苷酸多型性(SNP)标记数组面板。容忍的就职与相对稀罕的压力症状展出了更高的生长率。染色体上的二loci7和9强烈在一个山峰压力阶段在Zn缺乏下面与植物活力被联系。从一样的试验性的阴谋基于以前的microarray数据,我们加亮其表达式被重要遗传型或环境效果在Zn下面伴随的四候选人基因缺乏。网络基因本体论支持了已知的忍耐机制,例如维生素酸小径,并且也建议了光合作用基因的重要性克服Zn缺乏症状。
简介:TheAtomicWeaponsEstablishment(AWE)istaskedwithsupportingContinuousAtSeaDeterrence(CASD)bycertifyingtheperformanceandsafetyofthenationaldeterrentintheComprehensiveTestBanTreaty(CTBT)era.Thismeansthatrecoursetofurtherundergroundtestingisnotpossible,andcertificationmustbeachievedbysupplementingthehistoricaldatawiththeuseofcomputercalculation.Inordertofacilitatethis,AWEoperatessomeofthelargestsupercomputersintheUK.Tovalidatethecomputercodes,andindeedthedesignerswhoareusingthem,itisnecessarytocarryoutfurtherexperimentsintherightregimes.Anexcellentwaytomeetmanyoftherequirementsformaterialpropertydataandtoprovideconfidenceinthevalidityofthealgorithmsisthroughexperimentscarriedoutonhighpowerlaserfacilities.
简介:Recentresearchactivitiesrelevanttohighenergydensityphysics(HEDP)drivenbytheheavyionbeamattheInstituteofModernPhysics,ChineseAcademyofSciencesarepresented.RadiographyofstaticobjectswiththefastextractedhighenergycarbonionbeamfromtheCoolingStorageRingisdiscussed.Investigationofthelowenergyheavyionbeamandplasmainteractionisreported.WithHEDPresearchasoneofthemaingoals,theprojectHIAF(HighIntensityheavy-ionAcceleratorFacility),proposedbytheInstituteofModernPhysicsasthe12thfive-year-planofChina,isintroduced.
简介:高密度聚乙烯(HDPE)的薄墙样品经由注射塑造,不同注射速度从100mm/s到1200mm/s被准备。在张力的力量和幼仔模量的重要减少与增加注射速度被观察。为了在这后面调查机制,减少,取向,分子的重量,分子的重量分发,融化流动率,crystallinity和水晶HDPE的形态学用二维的宽角度的X光检查衍射(2D-WAXD)被描绘,胶化浸透层析(GPC),毛状的电流测定和微分扫描热量测定(DSC)分别地。这被表明取向,分子的重量,分子的重量分发,融化流动率和crystallinity没与增加有明显的变化注射速度。不过,扩大的链晶体的内容或大合拢的链晶体被发现与增加注射速度减少。因此,在张力的性质的减少被扩大的链晶体或大合拢的链晶体的减少的内容主要贡献,这被结束。这研究为高速度注射塑造的申请向工业提供珍贵信息。
简介:AnewtypeofSiO_2-MgO-CaO(SMC)whiskerwasusedtomodifyhighdensitypolyethylene(HDPE).Themeltingbehaviorandcrystallinitywereinvestigatedbydifferentialscanningcalorimetry(DSC).ThedispersionofwhiskersandinterfacialadhesioninthepreparedHDPE/SMCwhiskercompositeswereinvestigatedbyscanningelectronmicroscopy(SEM).Themechanicalpropertieswereevaluatedbymechanicaltestsanddynamicmechanicalanalysis(DMA).DSCdataindicatedthatthemeltingtemperatureandthecrystall...
简介:Adetailedstudywasperformedonthecrystalstructuresofpan-milledhigh-densitypolyethylene(HDPE)usingdifferentialscanningcalorimetry(DSC)andX-raydiffraction.ThecrystallinityofHDPEfirstdecreasedslightly,followedbyagradualincreasewithincreasingmillingtimes.Monocliniccrystalsappearedafter4cyclesofmilling.Withincreasingtimesofmilling,theproportionofmonocliniccrystalsincreasedsignificantlywhiletheproportionoforthorhombiccrystalsdecreasedgradually.Withincreasingtimesofmilling,thecrystallitesizeoforthorhombicformdecreasedgreatly,whilethesizeofmonocliniccrystalliteskeptalmostconstantduringmilling.
简介:Anenergyapproachisproposedtodescribetheelectromigrationinducedgrainrotationunderhighcurrentdensity.Thedrivingforceisassumedtoarisefromthegrain-boundaryenergyreductionandincreaseoftheinnerenergyfromthejouleheating.Energydissipatesbythegrainboundarydiffusionunderelectromigrationandviscousboundaryslidingisconsidered.Basedontheconservationofenergyproductionanddissipation,anequilibriumequationisdevelopedtopredictthegrainrotationrateanalytically.Itisrecognizedthatthegrainrotateswiththereducingofelectricalresistivityandinverselyproportionaltothegrainlength.Thetheoreticalpredictioniscomparedwiththeexperimentaldata,whichshowsgoodaccuracyontherotationtrendandthespecificrotationrate.
简介:LatticeBoltzmannmethodisoneofthewidelyusedinmultiphasefluidflow.However,thetwomaindisadvantagesofthismethodaretheinstabilityofnumericalcalculationsduetothelargedensityratiooftwophasesandimpossibilityofthetemperaturedistributiontobefedbackintothevelocitydistributionfunctionwhenthetemperatureissimulated.BasedonthecombinationprescribedbyInamuro,thelargedensityratiotwo-phaseflowmodelandthermalmodelmakesthedensityratioofthemodelsimulationtobeincreasedto2778:1byoptimizingtheinterfacedistributionfunctionoftwo-phasewhichimprovestheaccuracyofdifferentialformat.Thephasetransitiontermisaddedassourcetermintothedistributionfunctioncontrollingtwophaseorderparameterstodescribethetemperatureeffectonthegas-liquidphasetransition.Thelatentheatgeneratedfromthephasechangeisalsoaddedasasourcetermintothetemperaturedistributionfunctionwhichsimulatesthemovementoftheflowunderthecommoncouplingofdensity,velocity,pressureandtemperature.Thedensityandthetemperaturedistributionofsinglebubblearesimulated.Comparisonofthesimulationresultswithexperimentalresultsindicatesagoodagreementpointingouttheeffectivenessoftheimprovedmodel.
简介:Flowbatterieswithhighenergydensityandlongcyclelifehavebeenpursuedtoadvancetheprogressofenergystorageandgridapplication.Non-aqueousbatterieswithwidevoltagewindowsrepresentapromisingtechnologywithoutthelimitationofwaterelectrolysis,buttheysufferfromlowelectrolyteconcentrationandunsatisfactorybatteryperformance.Here,anon-aqueouslithiumbrominerechargeablebatteryisproposed,whichisbasedonBr2/Br-andLi+/Liasactiveredoxpairs,withfastredoxkineticsandgoodstability.TheLi/Brbatterycombinestheadvantagesofhighoutputvoltage(3.1V),electrolyteconcentration(3.0mol/L),maximumpowerdensity(29.1mW/cm2)andpracticalenergydensity(232.6Wh/kg).Additionally,thebatterydisplaysacolumbicefficiency(CE)of90.0%,avoltageefficiency(VE)of88.0%andanenergyefficiency(EE)of80.0%at1.0mA/cm2aftercontinuouslyrunningformorethan1000cycles,whichisbyfarthelongestcyclelifereportedfornon-aqueousflowbatteries.
简介:AnalgorithmforcomputationofcloudmotionwindshasbeendevelopedattheNationalSatelliteMeteorologicalCenterinChina.Since1997,ithasbeenappliedtocalculatethecloudmotionwindsfora1.25lat.×1.25long.meshoverthenorthwestPacificregionwiththesatellitedatafromGMS-5.Thedevelopmentofthetropicalcyclonesisstudied.Itshowsthatthetropicalcycloneisusuallyintriguedbythewesterlyjetstreamsattheupperlevelsofthetroposphere,whichmaybecausedbymid-latitudetroughswellextendingintothetropics.Duringtheprimeseasonofsummer,thewesterlyflowingequatorwardoftheTUTTmayalsobeacauseforthegenerationoftyphoons.
简介:Inthispaperwereviewthedesignanddevelopmentofa100J,10Hznanosecondpulsedlaser,codenamedDiPOLE100X,beingbuiltattheCentralLaserFacility(CLF).This1kWaveragepowerdiode-pumpedsolid-statelaser(DPSSL)isbasedonamasteroscillatorpoweramplifier(MOPA)design,whichincludestwocryogenicgascooledamplifierstagesbasedonDiPOLEmulti-slabceramicYb:YAGamplifiertechnologydevelopedattheCLF.Thelaserwillproducepulsesbetween2and15nsindurationwithprecise,arbitrarilyselectableshapes,atpulserepetitionratesupto10Hz,allowingreal-timeshapeoptimizationforcompressionexperiments.Oncecompleted,thelaserwillbedeliveredtotheEuropeanX-rayFreeElectronLaser(XFEL)facilityinGermanyasaUK-fundedcontributioninkind,whereitwillbeusedtostudyextremestatesofmatterattheHighEnergyDensity(HED)instrument.