学科分类
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6 个结果
  • 简介:Capacitydepletionisanimportantinformationrequiredforplanningofmultipurposereservoirs.Itisacomplexphenomenoninvolvingdiversefieldslikesurfacehydrology,sedimenttransport,variedflowhydraulicsandsoilconsolidation.Properassessmentofcapacityreductionishelpfulinascertainingthelifeofthereservoirandtheprojectbenefitsforcost/benefitanalysis.Inthisstudydimensionallyconsistentequationsfordepositionvolumeandthetrapefficiencyhavebeenobtained.Methodsofobtainingtheparametersinvolvedtheseequationshavealsobeenindicated.Itwasfoundthatthereisgoodagreementwiththefielddata.Itishopedthattheequationsareusefultodesignengineer.

  • 标签: Consolidation Dams Reservoir RESERVOIR life RESERVOIR
  • 简介:DepletionmodeHEMTwithrefractorymetalsilicideWSigatehasbeende-signedandfabricated.Epicated.Epitaxialmodulationdopingmaterialsweregrownbyahome-madeMBEsystem.Thegatelengthandwidthforlownoisedepletiondeviceswere1.2~1.5μmand2×160μmrespectively.Theelectronmobilityofthefabricateddevicesistypically6080cm^2/V·sat300Kand68000cm^2/V·sat77K.Thesheetelectronconcentrationnsis9×10^11cm^-2,Thesource-draincontactswithAuGeNi/Auwerefabricatedusingevaporatingandlift-offtechnique.tofurtherreducethecontactresistance,thewaferalloyedat520℃for3mininthehydrogen(H2)gas.SchottkygatewasformedusingWSi.Thetranseon-ductanceofthedepletionmodedeviceis110~130mS/mmatroomtemperature,Thede-vicescanbeappliedincommunicationsatelliteatmicrowavefreqencyof3.83GHzandradarreceiverat1.5GHz.Itsnoisefigureisabout2~3dB.

  • 标签: 硅化物 跨导 MBE材料 耗尽型HEMT 半导体工艺 难熔金属
  • 简介:根据接受比率方法,对在从另一个仔细放的大范围的一个大范围和一个盘子之间的弄空相互作用的影响被蒙特卡罗模拟学习。数字结果证明弄空潜力和弄空力量被仔细放的大范围的存在影响;大范围越近被放到他们,影响将是越多larger。而且,从另一个大范围的影响在弄空相互作用比到距离对角度更敏感。

  • 标签: 损耗力量 胶体悬浮 接收比率 蒙特卡洛模拟 数字结果
  • 简介:AerosolsampleswerecollectedonboardtheresearchvesselXuelongduringtheFifteenthChineseAntarcticResearchExpedition(CHINAREXV)inNovember1998-April1999andtheFirstChineseArcticResearchExpeditioninJuly-September1999.TheareastraversedbytheexpeditionarycruisesincludetheArcticOcean,thewesternNorthPacificOceanandtheeasternIndianOcean,covering75°N-69°Sand75°E-133°W.AerosolsampleswerealsotakenattheChineseZhongshanStationinEastAntarcticaduringtheCHINAREXV.Analysisofthesamplesyieldedconcentrationsofnon-sea-saltsulfateandothersolublechemicalspeciesinthemarineboundarylayer.Thedatasuggestthatthechemicalcompositionofthemarineaerosolsisinfluencedbythreemajorsources:continentalairmasses,primaryoceanicemissions,andsecondarymarineaerosolsoriginatedfromoceanicemissions.Theresultsshowthat,awingtostronganthropogenicsulfuremissionsfromtheAsiancontinent,non-sea-saltsulfateconcentrationsintheNorthernHemisphere(thewesternNorthPacific)marineaerosolaresignificantlyhigherthanthoseintheSouthernHemisphere(theeasternIndianOcean).Aerosolnon-sea-saltsulfateconcentrationsappeartobeinverselycorrelatedwithaerosolnon-sea-saltchloridewhichshowssignificantlynegativevalues,indicatingthelossofchloridebyseasalts,inmostaerosolsamples.SincegaseousHClmaybeinvolvedinchemicalreactionsthatdepleteatmosphericozoneinthemarineboundarylayer(MBL),highlevelsofacidicnon-sea-salt-sulfatereleasedbyhumanactivitiesinthelowandmid-latitudesoftheNorthernHemispheremaybecomeanimportantpotentialcontributortothelossofatmosphericozoneintheMBL.

  • 标签: non-sea-salt SULFATE MARINE BOUNDARY LAYER CHLORIDE
  • 简介:Aone-dimensionaltime-dependentphotochemicalmodelisusedtosimulatetheinfluenceofion-producedNOxandHOxradicalsontheAntarcticozonedepletioninpolarnightandpolarspringatalatitudeof73degreessouth.Verticaltransportandnitrogen-oxygen(NOx).hydrogen-oxygen(HOx)productionbyionicreactionshavebeenintroducedintothemodel.NOxandHOxproducedbyprecipitatingionsaretransportedintothelowerstratospherebyverticalmotionandhavesomeeffectsinthedevelopmentoftheAntarcticozonedepletion.Fromwinterthroughspringthecalculatedozonecolumndecreasesto269.4DU.However,thisvalueissignificantlyhigherthanthetotalozoneobservedatseveralAntarcticozonestations.

  • 标签: ozone PHOTOCHEMICAL depletion LATITUDE night polar