简介:TheHTScurrentleadsofsuperconductingmagnetsforlargescalefusiondevicesandhighenergyparticlecolliderscanreducethepowerconsumptionforcoolingby2/3comparedwithconventionalleads.Theresistivesectionsofhigh-ratedcurrentleadsareusuallymadeofaheatexchangercooledbygasflow.Thesupplyofthecoolingmassflowincursmorethan90%ofthecoolingcostfortheHTSleads.Themassflowraterequirementdependsnotonlyonthelengthandmaterialoftheresistiveheatexchanger,butalsoontheheattransfercoefficientandHEXsurface,thejointresistanceatthecoldendanditscoolingapproach.Thedesignandoperationofasheet-stackHEXwithalargerspecificsurfaceandamuchsmallerhydraulicdiameterarepresentedinthepaper.ThetestresultsofanHTSleadoptimizedfor8kAshowthata98.4%efficiencycanbeachieved.
简介:ThemagneticfusionreactorusingtheadvancedD-3Hefuelshastheadvantageofmuchless-neutronproductionssothattheconsequentdamagestothefirstwallarelessserious.Iftheestablishmentofthiskindofreactorbecomesrealistic,theexplorationof3Heonthemoonwillbelargelymotivated.Basedonrecentprogressesinthesphericaltorus(ST)research,wehavephysicallydesignedaD-3HefusionreactorusingtheextrapolatedresultsfromtheSTexperimentsandalsothepresent-daytokamakscaling.Itisfoundthatthereactorsizesignificantlydependsonthewallreflectioncoefficientofthesynchrotronradiationandoftheimpuritycontaminations.ThesecondaryreactionbetweenD-DthatpromptlyleadstotheD-Treactionproducing14MeVneutronsisalsoestimated.ComparisonofthisD-3HeSTreactorwiththeD-Treactorismade.
简介:Athreedimensionalsteady-statemagnetohydrodynamicmodelisdevelopedforthearcplasmainaDCsubmergedelectricarcfurnacefortheproductionoffusedMgO.Thearcisgeneratedinasmallsemi-enclosedspaceformedbythegraphiteelectrode,themoltenbathandunmeltedrawmaterials.Themodelisfirstusedtosolveasimilarprobleminasteelmakingfurnace,andthecalculatedresultsarefoundtobeingoodagreementwiththepublishedmeasurements.ThebehaviorofarcswithdifferentarclengthsisalsostudiedinthefurnaceforMgOproduction.Fromthedistributionofthearcpressureonthebathsurfaceitisshownthatthearcplasmaimpingementislargeenoughtocauseacrater-likedepressiononthesurfaceoftheMgObath.Thecirculationofthehightemperatureairundertheelectrodemayenhancethearcefficiency,especiallyforashorterarc.
简介:用不同束斑的SRXRF微不,对1个土壤成分分析标准物质和1个岩石成分分析标准物质进行了多点测量,通过样品缓慢移动,在2个土壤成分分析标准物质和2个岩名成分分析标准物质上分别选取2—3个高度为5mm的小区,进行扫描测量。结果表明,不论SRXRF微束束斑大小,标准参考物的均匀性都不是很好;在目前没有微束分析用的标准参考物的情况下,采用多区域扫描测量的方法,现有的标准参考物作质量控制是可行的。
简介:利用同步辐射(BSRF)漫散射站四圆衍射仪,对SiC体单晶的结构进行了判定以及对利用常压化学气相沉积(APCVD)生长的3C-SiC/Si(001)中的孪晶及含量进行了分析。六方{10-15}极图证明了该SiC单晶为6H(H为Hexagonal的缩写)结构。对3C-SiC外延薄膜,Φ扫描证明了3C-SiC外延生长于Si衬底上,外延取向关系为:(001)3C-SiC//(001)Si,[111]3C-SiC//[111]Si。3C-SiC的{111}极图在x=15.8°出现了新的衍射,采用六方{10-10}极图以及基体倒格点111、孪晶倒格点002的Mapping分析了x=15.8°处产生的衍射为3C-SiC孪晶所致,并利用ω扫描估算了孪晶的含量约为1%。