简介:Amodificationofthetransitionstatetheoryforevaporationandcondensationispresentedbyanalysingthekineticcharacteristicsofliquid-vapourinterphasetransport.Inthemodifiedtransitionstatetheory,themovingorientationofmoleculesisintroducedintothecalculationofthefreevolumeoftheactivatedcomplex.Thecondensationcoefficientsofargonatdifferenttemperaturesarecalculatedwiththemodifiedtransitionstatetheory.Theresultsagreewellwiththosefrommoleculardynamicssimulations.
简介:Thevolumeexpansionofthestuff(e.g.tobaccostem)isofgreatimportancetoanincreaseintheproductqualityandadecreaseintheproductioncost.Thispaterputsforwardthebasicconfigurationandtheexpansionmechanismofanewtypeofjetpressurizationevaporationexpansionapparatur.Bythethermodynamiccalculationoftheapparatus,wegivevariationsinsteampressureonvariouscrosssectionsoftheflowsystemfortheapparatus,manufactureasamplemachine,andfinishruntestsofthemachine.Thetestresultsshowthattheapparatusmaymaketherelativeincreaseinfillvalueoftobaccostemhigherthan75%,andmaycausethesteamconsumptionrequiredintheexpansionprocessofeachkilogramstemtoreducedabout40%comparedwithconventionalexpansionapparatus.Additionally,theconfigurationoftheapparatusissimpleandsmall,itscostofmanufactureisverylow,andbothitsoperationandmaintenanceareextremelyconvenient.
简介:Evaporationofsessilewaterdropletonpolydimethylsiloxane(PDMS)surfaceswiththreedi?erentcuringratios(5:1,10:1,and20:1)wasexperimentallyinvestigatedinthispaper.Weshowthattheconstantcontactradius(CCR)evaporationonsurfacewithhighcuringratiolastslongerthanthatwithlowcuringratio.WealsomeasuredYoung’smoduliofPDMSfilmsbyusingatomicforcemicroscopy(AFM)andsimulatedsurfacedeformationofPDMSfilmsinducedbysessilewaterdroplet.WithincreasingcuringratioofPDMSfilm,Young’smodulusofPDMSfilmisgettinglower,andthentherewillbelargersurfacedeformationandmoreelasticstoredenergy.Sincesuchenergyactsasabarriertokeepthethree-phasecontactlinepinned,thusitwillresultinlongerCCRevaporationonPDMSsurfacewithhighercuringratio.
简介:Modifiedrefractivity(M)profileisanimportantparametertodescribetheatmosphericrefractionenvironment,aswellasakeyfactorinuniquelyevaluatingelectromagneticpropagationeffects.Inordertoimprovethemodel-derivedMprofileinstable(especiallyverystable)conditions,threenonlinearsimilarityfunctions,namelyBH91,CB05,SHEBA07,areintroducedinthispapertoimprovetheoriginalBabin_V25model,andtheperformancesofthesemodifiedmodelsareverifiedbasedonthehydrometeorologicalobservationsfromtowerplatforms,whicharefinallycomparedwiththeoriginalBabin_V25modelandLocal_HYQ92model.Resultsshowthatintroducingnonlinearsimilarityfunctionscansignificantlyimprovethemodel-derivedMprofile;especially,thenewlydevelopedSHEBA07functionsmanagetoreducethepredictedrootmeansquare(rms)differencesofMandMslope(forboth0-5mand5-40m)by64.5%,16.6%,and60.4%,respectivelyinstableconditions.Unfortunately,thisimprovedmethodreactslittleontheevaporationductheight;incontrast,Local_HYQ92modeliscapableofreducingthepredictedrmsdifferencesofM,Mslope(forboth0-5mand5-40m),andevaporationductheightby76.7%,40.2%,83.7%,and58.0%respectively.Finally,anewrecommendationismadetoapplyLocal_HYQ92andBabin_SHEBA07inverystableconditionsconsideringthatMslopeismoreimportantthanevaporationductheightandabsoluteMvalueinuniquelydeterminingelectromagneticpropagationeffects.
简介:Manystudieshaveinvestigatedevaporationofsessiledropsinanattempttounderstandtheeffectofwettingontheevaporationprocess.Recentlyinteresthasalsoincreasedinthedepositionofparticlesfromsuchdrops,withevaporativemassfluxbeingdeemedtoberesponsibleforring-likedeposits,andcounteractionofthemassfluxbyMarangoniconvectionexplainingmoreuniformdepositionpatterns.Understandingofsuchdepositionprocessesisimportantinbiologicalapplications,suchastheLitostest-systemendorsedbytheRussianMinistryofHealthfordiagnosisofurolithiasisandtheevaporationofcolloidaldropsfordepositingandorganizingproteinsandDNA.Inmostcaseswheredepositionfromevaporatingdropshasbeenstudied,velocityinformationisinferredfromthefinaldepositionpatternorfrommathematicalmodelingbasedonsimplifiedmodelsofthephysicsoftheevaporationprocess.Inthisstudywehavedirectlymeasuredtheflowvelocitiesinthebaseofsessiledrops,usingmicroparticleimagevelocimetry,viewingthedropfrombelow,throughthecoverslide.Forwaterdrops,aradialpatternofflowwasobservedwithamaximumvelocityclosetobutnotatthepinnedouteredge.For‘azeotropic’ethanol/watermixtures,thevelocityfieldismorechaotictobeginwith,passingthroughaphaseinvolvingthreeorfourrecirculationcellsandfinallyhavingthesameradialpatternasforwaterdrops.
简介:Howtocontrolmeltcompositionisthekeyforgettinghighqualityalloymelt.Thepapermadethefollowingefforts:(1)TheactivitycoefficientsinTi-15-3melthavebeencalculated.(2)Takingadvantageoftheactivitycoefficients,theevaporationlossesofcomponentsinTi-15-3meltduringISMprocesshavebeenstudied.Thecalculatedresultsshowthatthereisacriticalvacuumdegree(about1.33Pa)duringmeltingprocess.
简介:Thevariabilityinglobaloceanicevaporationdatasetswasexaminedfortheperiod1988-2000.ThesedatasetsaresatelliteestimatesbasedonbulkaerodynamicformulationsandincludetheNASA/GoddardSpaceFlightCenterSatellite-basedSurfaceTurbulentFluxversion2(GSSTF2),theJapanese-oceanfluxusingremotesensingobservations(J-OFURO),andtheHamburgOcean-AtmosphereParametersandFluxesfromSatelliteversion2(HOAPS2).TheNationalCenterforEnvironmentalPrediction(NCEP)reanalysisisalsoincludedforcomparison.Anincreaseinglobalaveragesurfacelatentheatflux(SLHF)canbeobservedinallthedatasets.Empiricalmodedecomposition(EMD)showslong-termincreasesthatstartedaround1990forallremotesensingdatasets.TheeffectofMt.Pinatuboeruptionin1991isclearlyevidentinHOAPS2butisindependentofthelong-termincrease.Linearregressionanalysesshowincreasesof9.4%,13.0%,7.3%,and3.9%forGSSTF2,J-OFURO,HOAPS2andNCEP,fortheperiodsofthedatasets.Empiricalorthogonalfunction(EOF)analysesshowthatthepatternofthefirstEOFofalldatasetsisconsistentwithadecadalvariationassociatedwiththeenhancementofthetropicalHadleycirculation,whichissupportedbyothersatelliteobservations.ThesecondEOFofallfourdatasetsisanENSOmode,andthecorrelationsbetweentheirtimeseriesandanSOIare0.74,0.71,0.59,and0.61forGSSTF2,J-OFURO,HOAPS2,andNCEPinthatorder.WhentheHadleymodesareremovedfromtheremotesensingdata,theresidueglobalincreasesarereducedto2.2%,7.3%,and<1%forGSSTF2,J-OFUROandHOAPS,respectively.IftheENSOmodeisusedasacalibrationstandardforthedatasets,theHadleymodeisatleastcomparableto,ifnotlargerthan,theENSOmodeduringourstudyperiod.
简介:Molybdenumoxidenanostructuredthinfilmsweregrownonfluorinedopedtinoxide(FTO),indiumdopedtinoxide(ITO)andordinaryglasssubstratesbythermalevaporationprocesswithoutvacuumandcatalystsusingmolybdenumtrioxide(MoO3)powderasasourcematerialandoxygenasacarriergas.Variousmorphologiesincludingnanobelts,disksandhexagonalrod-likenanostructureswereobtainedbychangingthesourceandsubstratetemperaturesduringthegrowthofMoO3thinfilms.Structuralparameters,morphology,compositionandsurfacefeaturesofthefilmswerecharacterizedbyXRD,SEM,EDAX,XPS,AFMandRamanspectroscopy.Thefilmswereorthorhombicinstructurewithpreferredorientationalong(010)plane.Morphologyanalysisrevealsrandomlyalignednanobeltswith40nminthicknessandawidthof800nmand3–12mminlength.Thediskshave1.5μmdiameters,1μmthicknessandhexagonalrod-likenanostructureswithalength,breathandwidthof2μm,1μmand100nmareformed.ThesampleswereinvestigatedunderdarkandphotocurrentconditionsinH2SO4aqueoussolutionasafunctionofappliedpotential.ThephotocurrentdensityofsamplespreparedonITOandFTOsubstratesampleswerecomparedandtheresultsarediscussed.
简介:生物土壤外壳为在干旱、半干旱的desertification区域改进生态的环境用作一个前卫。它是本地生态的环境正在承担的改进的水平的好指示物。在荒芜的区域,水状况是改进生态的环境的一个关键因素。作为第一层保护,生物外壳由于他们保存并且维持潮湿的能力在本地植被继任起一个重要作用。把在Ningxia省的Yanchi荒芜的Maowusu用作一个例子,在三年研究以后,当研究反对,这篇论文包括在Artemisiaordosica的盖子下面的地衣,苔藓和cyanobacterial选择三种生物外壳。这研究的结果显示那,外壳越近生物到Artemisiaordosica植被,他们越thicker变得。在Artemisiaordosica植被的一样的位置,苔藓外壳的厚度最高,由cyanobacterial外壳的地衣外壳,和厚度列在后面最低。生物土壤外壳范围保护土壤层的自然的水内容免受0~5 的伤害;厘米。另外,它完成掉落的水到更深渗透,并且不能阻止表面水内容有效地蒸发。堵住水渗入的生物外壳的效果随降雨的增加减少。在一样的降雨水平,苔藓外壳提供最强壮的水渗入阻塞,由地衣外壳和cyanobacterial外壳列在后面。随降雨的增加,水渗入的深度增加。在一样的降雨水平,水渗入深度的关系如下:cyanobacterial外壳>地衣外壳>苔藓外壳。随生物外壳厚度的增加,他们堵住水渗入能力更强壮,并且水渗入的深度更小。生物外壳上的模仿的降雨过程的特征上的分析证明沙的土地能被使用适当人工的生物外壳造一个持续森林保护系统并且在desertification区域创造一个稳定的生态系统修理。
简介:Abaroclinicsemi-geostrophicmodelwithevaporation-windfeedbackmechanism(EWFM)andCISKisestablished,twonon-dimensionalparametersaandηareintroducedtorepresentEWFMandCISK,respectively.Analyticsolutionsofthemodelsystemareobtained,dynamicsanalysesandthemodelatmospherecalculationsfurtherconfirmthatEWFMandCISKareveryimportantphysicalprocessesinleadingtothelow-frequencyoscillationsinthetropics.
简介:AresearchonkineticsofAlevaporationfromliquidU—Alalloyswasmadeinavacuuminductionmelting(VIM)furnaceat1673—1843K.TheevaporationrateofAlwasfoundtobefirstorderwithrespecttoAlcontentinthemelt.TheoverallmasstransfercoefficientofAlwasdeterminedanditwasfoundthattheevaporationrateofAlincreasedwithincreasingtemperatures.TheapparentactivationenergyofAlevaporationat1673-1843Kwas171.5kJmol-1.ThevalueofmasstransfercoefficientofAlintheliquidphasewasestimatedtobe3.77×10-6,7.41×10-6,and9.40×10-6ms-1at1673,1753,and1843K,respectively.Meanwhile,ratedeterminingstepswerediscussedanditwasconcludedthattheevaporationrateofAlismainlycontrolledbyliquidphasemasstransfer.
简介:Aprocesssuitableforproductiononalargescaleofcoldlightmirrorforfilmprojectorisintroduced.DepositionparametersrequiredforproducingTiO2/SiO2opticalmultialyersystemsbyelectronbeamevaporationofTiO2andSiO2startingmaterialsareinvestigated.Manufactureandtechniquesofcoldmirrorandtheadhesion,stability,wearandcorrosionresistanceofcoldmirrorbythisprocessarediscussed.Theresultshowsthatcoldmirrorproducedhasgoodopticalpropertiesandbetteradhesion.
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简介:ThispaperdealswiththeformingageoftheShuiquangougold-bearingalkalinerockwiththehelpofthesinglezirconPb-evaporationmethod.Theapparentage(16-7-1667Ma)gotformcrystallinezircongraindomains,wherethereexistsanalmostenclosedsystem,isingoodagreementwithzirconU-Pbconventionalupperinterceptage(1718Ma),suggestingthattheShuiquangougold-bearingalkalirockintrudedat1600-1700Maago.
简介:水晶的Au5Si2/Si异质接面nanowires(Au5Si2/SiNWs)被热蒸发的SiO粉末在一个低真空系统在厚黄金涂的硅底层上获得。生产Au5Si2/Si异质接面的结构分析被采用一台传播电子显微镜(TEM)和一个选择区域执行电的衍射计。化学作文被纳入TEM的一个精力散的X光分光镜学习。一个二拍子的圆舞生长模型被建议描述Au5Si2/SiNWs的形成。在第一步期间,水晶的SiNWs经由在相对高的温度把帮助氧化物的生长过程与vapour-liquid-solid模型相结合的生长机制被形成。在第二步,preformedSiNWs的温度减少和减少片断与残余Au反应由一个solid-liquid-solid过程形成单个水晶的Au5Si2nanowires。现在的工作应该基于nanowires为未来合成和高质量的金silicidenanowires和微电子设备的研究是有用的。