简介:Tianqiaocarbonate-hostedPb-Zndeposit,controlledbyNW-trendingF37thrustfaultandNW-trendingTianqiaoanticline,islocatedintheeasternpartofSichuan-Yunnan-Guizhou(SYG)Pb-Znmetallogenicprovince,southwesternYangtzeBlock,southwestChina.OrebodiesinthisdepositarehostedintheDevonian-Carboniferouscarbonaterocks,andoremineralsincludesphalerite,galenaandpyrite,whiletheganguemineralsaredominatedbycalciteanddolomite.Usinghigh–precisionsolidthermalionizationmassspectrometry(TIMS),thispaperreportsthestrontiumisotopiccompositions(0.7119to0.7167)ofsulfidesamplesfromtheTianqiaodepositinordertotracetheoriginofhydrothermalfluids.Comparedwiththecountryrocks,thecalculated87Sr/86Sr200Mavaluesofsulfiderangefrom0.7118to0.7130,higherthanthoseoftheage-correctedDevoniantoPermiansedimentaryrocks(0.7073to0.7101)andtheMiddlePermianEmeishanfloodbasalts(0.7078to0.7039),butlowerthanthoseoftheage-correctedProterozoicbasementrocks(suchastheKunyangandHuiliGroups,87Sr/86Sr200Ma=0.7243to0.7288).Thisimpliesamixedstrontiumsourcebetweentheolderbasementrocksandtheyoungercoversequences.Togetherwithgeologicandpreviousisotopicevidences,weconsideredthatthefluids'mixingisapossiblemechanismforsulfideprecipitationintheTianqiaodeposit.
简介:Asoneofcandidatesforthefuelcladdingorstructurematerialusedinfourthgenerationfissionandfusiondemonstratereactor,MAXphasehasthepropertiesofbothceramicandmetal,suchashighmeltingpoint,hightemperaturestability,gooderosionresistanceandradiation-damagetolerance[1;2].Maxphaseisaseriesofceramicsofnanolamellarandhexagonalstructure.Mrepresentstransitionelement.Arepresentsthethirdorfourthmaingroupelement.XrepresentNandC.Inthedesignoflead-cooledfastreactor,itisrequiredthatthematerialshouldendurethecorrosionofliquidPb-Bialloy.Therefore,understandingoftheoxidelayersandtheirgrowthmechanismsinLBEisfundamentallyimportantforthedevelopmentofcandidatematerials.
简介:210Pbwasmeasuredduringthe3rdChineseNationalArcticResearchExpeditioncruisetoinvestigateitsspatialpatterninthewesternArcticOcean,aswellasitsrelationwiththethermoclineintheCanadianBasin.Thespecificactivitiesvariedfrom0.04to2.72,<0.013to4.37,and0.1to4.85Bq/m3fordissolved,particulate,andbulk210Pb,respectively,correspondingtorespectiveaveragesof0.65,0.43,and1.08Bq/m3.IntheCanadianBasin,theminimum210Pbactivitiesoccurredinthethermocline,whichwascharacterizedbylowtemperatureof-1.52°Candsalinityof33.1.Combiningthespatialdistributionof210PbandhydrographicalcharacteristicsinthewesternArcticOcean,thisscenariowasascribedtotheeffectivescavengingof210PbwhenthePacificwaterflowedacrosstheChukchiShelf.Quantitatively,thisinterpretationwassupportedbyboththeshorterresidencetimesandhigherscavengingefficiencies(SE)ofdissolved210PbovertheChukchiShelf.ThehighestSEvalueswereobservedintheHeraldShoalandbottomwatersovertheslope.
简介:由于3-(异丁烯酰氧)丙基三甲氧基硅烷具有能同时进行自由基聚合的乙烯基和水解-缩合反应的硅氧烷基,因而它是制备兼具有机材料和无机材料优良性质杂化材料的优良单体。利用其硅氧炕基水解-缩合或者进一步缩合反应的性质,将其与其它材料聚合或接枝可达到优化材料的目的。
简介:ThisstudyinvestigatedthevolatilizationkineticsofleadinpelletsmadeofZn-Pb-bearingdustsmixedwithcoalpowder,inanitrogenatmosphereandinthetemperaturerangebetween1100℃-1300℃,andshowedthatthereductiontemperaturehasasignificanteffectonthevolatilizationrateofleadandthatneithertheparticlesizeofthecoalpowdernortheextracarboncontenthasanyeffectonthevolatilizationrate.Theobtainedactivationenergyforthevolatilizationofleadis88.74kJ/mol.Thevolatilizationrateofleadiscontrolledbyboththeleadevaporationreactionandthediffusionofgaseousleadthroughthegasboundarylayercoveringthesurfaceofthereducedliquidlead.