简介:Thermoelectric(TE)materialsareakindoffunctionalmaterialswhichcanbeusedtoconvertdirectlyheatenergytoelectricityorreversely.Thethermoelectriceffectsholdgreatpotentialforapplicationinpowergenerationandrefrigeration.Bi2Te3anditsalloysarewellknownasbestTEmaterialscurrentlyavailablenearroomtemperature.Thispaperstudiesrespectivelytheeffectsofsparkplasmasintering(SPS)onelectricperformanceofBi0.5Sb1.5Te3thermoelectricmaterialsthatarepreparedthroughvacuummeltingandballmilling.ThroughX-rayDiffractionandcoldfieldemissionscanningelectricmicroscopes4800,thephaseconstituentandmicrostructureoftheTEmaterialssampleswereanalyzed.ElectricconductivityandpowerfactorcanbeimprovedwiththeriseofSparkPlasmaSinteringtemperature(from300to500℃)andpressure(from30to60MPa),andthedensityandmechanicalstrengthofBi0.5Sb1.5Te3thermoelectricmaterialincrease,too.
简介:ExtractingB2O3fromcalcinedboronmud(CBM)wasstudied.TheeffectoffactorssuchasreactiontemperatureandNaOH-to-CBMmassratioonB2O3extractionefficiencywasinvestigated.TheresultsshowthatincreasingreactiontemperatureandNaOH-to-CBMmassratioincreasesB2O3extractionefficiency.TherearetwostagesfortheB2O3extractingprocess:0–20ministhefirststage,whichisrapid;20–50ministhesecondstage,whichisslowerthanthefirststage.Theoverallextractingprocessfollowstheshrinkingcoremodel,andthefirstandsecondstagesaredeterminedtoobeythesurfacechemicalreactionmodelandthediffusionthroughtheproductslayermodel,respectively.Theactivationenergiesofthefirstandsecondstagesarecalculatedtobe41.74and15.43kJ·mol-1,respectively.TheB2O3extractingkineticsequationsofthefirstandsecondstagesarealsoobtained.
简介:CaTiO3的形成行为在钛铁矿的electro-deoxidization期间专注准备FeTi合金被实验和模拟调查。结果显示中间的产品的形成和分解,CaTiO3,在钛铁矿的electro-deoxidization期间是不可避免的步专注。CaTiO3能在电气化学的过程期间通过熔融的盐和电气化学反应的hydrolyzation被产生。为CaTiO3的产生的主要原因在阴极是在从熔融的盐和TiO2的Ca2+之间的电气化学反应。与electro-deoxidization继续,CaTiO3是进一步的electrolyzed形成钛低值氧化物。当在由在sintering期间增加CaCO3的阴极的CaTiO3形式处理时,当前的效率能被改进。
简介:ElectrocrystallizationMechanismofTungsteninMoltenKF-B_2O_3-K_2WO_4WenZhenhuanandLiGuoxun文振环,李国勋(GeneralResearchInstiiuteforNo...
简介:polyacrylonitrile(平底锅)上的electrodepositingFe-Cr2O3合成涂层的过程基于碳纤维,它的催化graphitization被学习。有或没有electrodepositedFe-Cr2O3合成涂层的碳纤维是在不同温度对待的热,结构的变化被XRD,拉曼光谱学和SEM描绘。结果显示那Fe-Cr2O3合成涂层在低温度在碳纤维的graphitization上展出重要催化效果。当Fe-Cr2O3-coated碳纤维是时,热对待在1300?慢敳?慣'R湯映扩牥映汥?獡琠敨瀠敲畣獲牯映汯潬敷?祢椠灭敲湧瑡潩?楷桴爠獥湩?潭摬湩?湡?敨瑡琭敲瑡敭瑮楴?楴吗??
简介:Thecorrosionfatiguebehaviorofepoxy-coatedMg–3Al–1Znalloywasinvestigatedinairand3.5wt%NaClsolution.Epoxycoatingasanewmethodwasusedtoimprovethecorrosionfatiguepropertyofthematerial.Resultsshowthatthefatiguelimit(FL)ofthecoatedspecimensishigherthanthatoftheuncoatedspecimensin3.5wt%NaClsolutionbecauseofthestrengtheningandblockingfunctionsoftheepoxycoating.TheFLofthecoatedspecimensin3.5wt%NaClsolutionisashighasthatinair.Itimpliesthatthecoatedspecimensarenotassensitivetotheenvironmentasthemagnesiumalloy.Thelowtensilestrengthandtheshortelongationofthepureepoxycoatingleadtothatthefatiguecrackofthecoatedspecimenisalwaysinitiatedfromtheepoxy-coatingfilmPoresandpinholesacceleratethefatiguecrackinitiationprocess.PinholesarecausedbythecorrosionreactionsbetweentheepoxycoatingandtheNaClsolution.