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378 个结果
  • 简介:Wenumericallydemonstrateanovelultra-broadbandpolarization-independentmetamaterialperfectabsorberinthevisibleandnear-infraredregioninvolvingthephase-changematerialGe2Sb2Te5(GST).Thenovelperfectabsorberschemeconsistsofanarrayofhigh-indexstrong-absorbanceGSTsquareresonatorsseparatedfromacontinuousAusubstratebyalow-indexlosslessdielectriclayer(silica)andahigh-indexGSTplanarcavity.Threeabsorptionpeakswiththemaximalabsorbanceupto99.94%areachieved,owingtotheexcitationofplasmon-likedipolarorquadrupoleresonancesfromthehigh-indexGSTresonatorsandcavityresonancesgeneratedbytheGSTplanarcavity.Theintensitiesandpositionsoftheabsorptionpeaksshowstrongdependenceonstructuralparameters.AheattransfermodelisusedtoinvestigatethetemporalvariationoftemperaturewithintheGSTregion.TheresultsshowthatthetemperatureofamorphousGSTcanreachupto433Kofthephasetransitiontemperaturefromroomtemperatureinjust0.37nswitharelativelylowincidentlightintensityof1.11×108W∕m2,duetotheenhancedultra-broadbandlightabsorbancethroughstrongplasmonresonancesandcavityresonanceintheabsorber.Thestudysuggestsafeasiblemeanstolowerthepowerrequirementsforphotonicdevicesbasedonathermalphasechangeviaengineeringultra-broadbandlightabsorbers.

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  • 简介:Anewpotassiumnitrate(KNO_3)/diatomiteshape-stabilizedcompositephasechangematerial(SSCPCM)waspreparedbythemixingandsinteringmethod.KNO_3servedasthephasechangematerial(PCM)forthermalenergystorage,whilediatomiteactedasthecarriermatrixtoprovidethestructuralstrengthandpreventtheleakageofPCM.ItwasfoundthatKNO_3couldberetained65wt%intoporesandonsurfacesofdiatomitewithouttheleakageofmeltedKNO_3fromtheSS-CPCM.ThecalculatedfillingrateofmoltenKNO_3thatcouldenterintothedisc-likeshapeporeofdiatomiteverifiedthescanningelectronicmicroscopyimagesofSS-CPCM.X-raydiffractionandFouriertransforminfraredspectroscopyresultsshowedthatnoreactionoccurredbetweenKNO_3anddiatomite,performinggoodcompatibility.Accordingtothedifferentialscanningcalorimetryresults,after50thermalcycles,thephasechangetemperaturesformeltingandfreezingofSS-CPCMwith65wt%KNO_3werechangedfrom330.23°Cand332.90°Cto330.11°Cand332.84°Candcorrespondinglatentheatsvariedfrom60.52J/gand47.30J/gto54.64J/gand41.25J/g,respectively.TheKNO_3/diatomiteSS-CPCMmaybeconsideredasapotentialstoragemediainsolarpowerplantsforthermalenergystorage.

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  • 简介:海洋的循环和气候的学习要求能精确地模仿tracer旋涡散开和移流的模型。传统的Eulerian坐标能由于轴的不正确的排列介绍大人工的水平扩散性/粘性,这被显示出。因此,如此的模型能涂锋利的前面并且介绍另外的数字人工制品。为有相对低的分辨率的模拟,大侧面的散开明确地在模型被使用;因此,如此的数字散开不能是一个问题。随水平分辨率的增加,然而,在通常使用的Eulerian坐标与水平移流联系的人工的扩散性/粘性可以为精确地为海洋发行量建模成为最挑战性的障碍之一。Isopycnal旋涡散开(混合)广泛地在数字模型被使用了。普通智慧是沿着isopycnal混合是精力免费。然而,小心的考试表明这不是事实。事实上,旋涡散开能概念上被分开成二步:激动人心并且subscale散开。由于thermobaric效果,激动人心,或交换水集中,沿着isopycnal,表面处于吝啬的状态与GPE的变化被联系。这是不稳定性的一种新类型,叫了thermobaric不稳定性。另外,由于cabbelingsubscale,水包裹的散开总是导致GPE的版本。GPE的版本可以由于激动人心的isopycnal和subscale散开导致thermobaric不稳定性。

  • 标签: 涡流扩散 数值扩散 重力势能 对流 能量学 水平分辨率
  • 简介:StaticCoulombstresschangeinducedbyearthquakeslipisfrequentlyusedtoexplainearthquakeactivitiesandaftershockdistribution.However,someparametersfortheCoulombstresscalculationareunabletobewellconstrainedfromlaboratoryexperimentsandfieldobservations.DifferentparametersmaydirectlyaffectthepatternofstaticCoulombstress.ThestaticCoulombstresschangesinducedbytheWenchuanearthquakecalculatedbysixresearchgroupsarenotconsistentwitheachother.Toinvestigatehowtheparametersaffectthecalculationresults,wechangetheparametersinturnthroughmodelingandcomparetheresultsofdifferentcalculationparameters.Wefindthatgravity,positionandstrikeofreceiverfaultshavelittleinfluenceoncoseismicCoulombstresscalculations,butotherparameterscanchangethevalueandsignoftheresultsinvariousdegreesespeciallyaroundtheearthquakeruptureplane.ThereforetheuncertaintyanalysisofstaticCoulombstresschangeinducedbyearthquakeshouldbetakenintoconsiderationintheearthquakehazardanalysis.

  • 标签: 不确定性分析 库仑应力 地震发生 应力变化 静态 汶川
  • 简介:ThisArticlepresentsathreedimensionalnumericalmodelinvestigatingthermalperformanceandhydrodynamicsfeaturesoftheconfinedslotjetimpingementusingslurryofNanoEncapsulatedPhaseChangeMaterial(NEPCM)asacoolant.Theslurryiscomposedofwaterasabasefluidandn-octadecaneNEPCMparticleswithmeandiameterof100nmsuspendedinit.AsinglephasefluidapproachisemployedtomodeltheNEPCMslurry.ThethermophysicalpropertiesoftheNEPCMslurryarecomputedusingmodernapproachesbeingproposedrecentlyandgoverningequationsaresolvedwithacommercialFiniteVolumebasedcode.TheeffectsofjetReynoldsnumbervaryingfrom100to600andparticlevolumefractionrangingfrom0%to28%areconsidered.ThecomputedresultsarevalidatedbycomparingNusseltnumbervaluesatstagnationpointwiththepreviouslypublishedresultswithwaterasworkingfluid.ItwasfoundthataddingNEPCMtothebasefluidresultswithconsiderableamountofheattransferenhancement.ThehighestvaluesofheattransfercoefficientsareobservedatH/W=4andC_m=0.28.However,duetothehigherviscosityofslurrycomparedwiththebasefluid,theslurrycanproducedrasticincreaseinpressuredropofthesystemthatincreaseswithNEPCMparticleloadingandjetReynoldsnumber.

  • 标签: 三维数值模型 相变材料 数值研究 浆料粘度 冲击冷却 射流
  • 简介:Usingatimeseriesmethodthatcombinesboththepersistentscattererandsmallbaselineapproaches,weanalyzed9scenesEnvisatASARdataovertheL’Aquilaearthquake,andobtainedaShocke’sdisplacementfieldanditsevolutionprocesses.Theresultsshowthat:(1)EnvisatASARclearlydetectedthewholeprocessesofdisplacementfieldoftheL’Aquilaearthquake,anddistinctvariationsatdifferentstagesofthedisplacementfield.(2)Preseismiccreepdisplacement?displacementmutationwhenfaulting?constantlysloweddownaftertheearthquake.(3)Theareaofthestrongestdeformationandgroundrupturewasalow-lyingovaldepressionregiontothesoutheast.Surfacefaultingwithinazoneofabout22km914km,withanorientationof135°,occurredalongtheNW-strikingandSW-dippingPaganica-S.Demetrionormalfault.(4)Inanalyzinganareaofabout54km959km,boundedbynorth–southaxistotheepicenter,thedisplacementfieldhassignificantcharacteristicsofawatershed:westwardoftheepicentershowsupliftwithmaximumof130mminline-of-sight(LOS),andeastoftheepicenterwasaregionwith220mmofmaximumsubsidenceintheLOS,concentratingontherupturezone,themajorityofwhichformedinthecourseoffaultingandsubsequence.

  • 标签: 位移场 线方法 地震 散射 永久 ENVISAT
  • 简介:做Si的Ge(2)sb(2)Te(5)电影被dc劈啪作响magnetronco与Ge2Sb2Te5和Si目标准备了。在在两结晶化温度和阶段转变温度fromface-centred-cubic(fcc)的增加的Te(5)电影结果分阶段执行到的Ge(2)sb(2)的Si的增加六角形(十六进制)阶段。Ge2Sb2Te5电影的抵抗力显示出重要增加,Si做。当在这部电影做Si的11.8at.%时,在退火的460度C以后的抵抗力与undopedGe2Sb2Te5电影相比从64~99终止从1~11m终止(.)厘米和动态抵抗增加增加。这对写阶段变化随机存取记忆的当前的减小很有用。

  • 标签: GE2SB2TE5薄膜 掺杂 随机存储 相变 结晶温度
  • 简介:OnthebasisofthepreviousstudiesofthelayeredcrustalmodelintheYutianarea,combinedwiththefieldGPScontinuousobservationdata,weroughlyestimatetheviscouscoefficientofeachlayer.Withtheviscoelastichorizontallayermodel,wecalculatetheviscoelasticco-seismicCoulombstresschangecausedbytheYutianM_S7.3earthquakes2008and2014respectively.BasedontheCoulombstresschange,usingthecalculationmethodof"direct"aftershockfrequency,wecomeupwiththetheoreticalearthquakefrequencydirectlyrelatedtothemainshockandtheco-seismicCoulombstresschangeinthestudyarea.Thenweputforwardamethod,basedonthecomparisonoftheoreticalandactualearthquakefrequencyorthecomparisonbetweentheoreticalandpracticalearthquakefrequency-distancedecaycurvefittingresiduals,toestimatethemagnitudeofamaximumsequentearthquake,directlyrelatedtothemainshockco-seismicCoulombstresschange.Resultscalculatedbydifferentmethodsshowthatthemaximumfollow-upearthquakemagnitudecausedbythecoseismicCoulombstresschangeliesfromM_S7.2toM_S7.5followingYutianM_S7.3earthquakein2008;butthatofthe2014YutianM_S7.3earthquakeisM_S6.3.TheformerisveryclosetotheYutianM_S7.3earthquakein2014.Becauseofthesamemagnitude,relativelyclosespatialdistance,shorttimeinterval,thesameregionoftheexternalforce,thestrongcorrelationbetweentwoseismictectonicandaclearstressinteraction,wethusconsiderthatthetwoYutianM_S7.3earthquakesin2008and2014constituteapairofgeneralizeddoubleshocktypeearthquake.Thisisconsistentwiththesequencetypecharacteristicofpast"doubleshock"earthquakesintheregion.Inthispaper,theinfluenceofthemagnitudelowerlimitandtheb-valueintherelationshipofG-Rontheresultsisdiscussed.Asaresult,whentheviscoelasticcoseismicCoulombstressvariationisdetermined,thelowerlimitofmagnitudehaslittleeffectonthemaximumsequentearthquakemagnitude

  • 标签: 最大地震震级 库仑应力 应力变化 估计 黏弹性 地震频率
  • 简介:UsingaregionalclimatemodelMM5nestedtoanatmosphericglobalclimatemodelCCM3,aseriesofsimulationsandsensitivityexperimentshavebeenperformedtoinvestigatetherelativeLGMclimateresponsetochangesofland-seadistribution,vegetation,andlarge-scalecirculationbackgroundoverChina.Modelresultsshowthatcomparedwiththepresentclimate,thefluctuationsofsea-landdistributionineasternAsiaduringtheLGMresultinthetemperaturedecreaseinwinterandincreaseinsummer.IthassignificantimpactonthetemperatureandprecipitationintheeastcoastalregionofChina.TheimpactonprecipitationintheeastcoastalregionofChinaisthemostsignificantone,with25%-50%decreaseinthetotalprecipitationchangeduringtheLGM.Ontheotherhand,thechangesinsea-landdistributionhavelessinfluenceontheclimateofinlandandwesternpartofChina.DuringtheLGM,significantchangesinvegetationresultintemperaturealternatingwithwinterincreaseandsummerdecrease,butdifferencesintheannualmeantemperatureareminor.DuringtheLGM,theglobalclimate,i.e.,thelarge-scalecirculationbackgroundhaschangedsignificantly.ThesechangeshavesignificantinfluencesontemperatureandprecipitationoverChina.Theyresultinconsiderabletemperaturedecreasesinthisarea,anddirecttheprimarypatternsandcharacteristicsoftemperaturechanges.Resultsdisplaythat,northeasternChinahasthegreatesttemperaturedecrease,andthetemperaturedecreaseintheTibetanPlateauislargerthanintheeasternpartofChinalocatedatthesamelatitude.Moreover,thechangeoflarge-scalecirculationbackgroundalsocontrolsthepatternofprecipitationchange.Resultsalsoshowthat,mostofthechangesinprecipitationoverwesternandnortheasternpartsofChinaaretheconsequencesofchanginglarge-scalecirculationbackground,ofwhich50%-75%ofprecipitationchangesovernorthernandeasternChinaaretheresultsofchangesinlarge-scalecirculationbackground.OverChina,theLGM

  • 标签: 海岸分布 植被 患流量 LGM 中国 气候
  • 简介:Netprimaryproduction(NPP)ofcroprepresentsthecapacityofsequestratingatmosphericCO_2inagro-ecosystem,anditplaysanimportantroleinterrestrialcarboncycling.BylinkingtheCrop-CmodelwithclimatechangescenarioprojectedbyacoupledGCMFGOALSviageographicalinformationsystem(GIS)techniques,cropNPPinChinawassimulatedfrom2000to2050.ThenationalaveragedsurfaceairtemperaturefromFGOALSisprojectedtoincreaseby1.0℃overthisperiodandthecorrespondingatmosphericCO_2concentrationis535ppmby2050undertheIPCCAIBscenario.Withaspatialresolutionof10×10km~2,modelsimulationindicatedthatanannualaverageincreaseof0.6TgCyr~(-1)(Tg=10~(12)g)wouldbepossibleundertheAIBscenario.TheNPPinthelate2040swouldincreaseby5%(30TgC)withinthe98×10~6hm~2croplandareaincontrastwiththatintheearly2000s.AfurtherinvestigationsuggestedthatchangesintheNPPwouldnotbeevenlydistributedinChina.AhigherincreasewouldoccurinamajorityofregionslocatedineasternandnorthwesternChina,whileaslightreductionwouldappearinHebeiandTianjininnorthernChina.ThespatialcharacteristicsofthecropNPPchangeareattributedprimarilytotheunevendistributionoftemperaturechange.

  • 标签: 农作物 净初级生产量 农业生态系统 气候变化 作物-碳模型
  • 简介:CryogenianDatangpo形成在在Sturtian和Marinoan冰川期之间的间冰期的时间期间被扔。我们在东北贵州从基础Datangpo形成学习了氮同位素作文和黑页岩的瞬间的内容,华南,海洋的氧化还原作用变化和氮在间冰期的时间期间骑车一次尝试重建。象geochemical侧面一样基于岩石层位学,基础黑页岩能被划分成四间隔:间隔1有最低15N价值(+5.0);在间隔2,15N价值在+6.4和+7.4(第一座山峰)之间变化;15在+6附近的N;并且间隔4被它的更高的15N价值,在+6.7和+7.8(第二座山峰)之间。瞬间的丰富因素的价值与上升stratigraphic趋势从56.8~2.6减少。它在Sturtian冻结成冰以后立即显示了那,在在到Yangtze站台的南部的边缘的斜坡的架之间的过渡地区上面的海洋的海水被成层,与浅海水是oxic,但是深水beingsulfidic。随后,尽管有一个oxic条件的短出现,高denitrification率在表面海水在扩展suboxic区域占优势,并且深海水仍然是缺氧或平的euxinic。

  • 标签: 中国南方地区 氧化还原 间冰期 大塘坡 氮循环 钼含量
  • 简介:Si16Sb84-based线房间阶段变化随机存取记忆(PCRAM),在哪个Si16Sb84阶段变化线被听电极与nanoscale差距联系,被为重设操作的最低当前、测量的脉搏宽度是的电子横梁平版印刷术制作115μA和18ns,分别地为再结晶的测量最短的脉搏宽度是110ns,与1.5V的应用脉搏振幅。为有不同的线长度的线房间的集合和重设电流是坚定的。106的耐力与上面的电阻比率骑车800被完成了。

  • 标签: 低能耗相位 SiSb 薄膜 电极