简介：ThesurfacecompositionandelectronicstructureoftungstencarbidespreparedbydirectsynthesisandcarburizationofwhitetungsticacidwerestudiedwithX-rayphotoelectronspectros-copy.TheexperimentalresultsshowthatWO3andfreecarbonarepresentonthesurfaceofthecarbides.Forthehighsurfaceareatungstencarbidepreparedfromwhitetungsticacidalargeextentofoxygeninsertionintothecrystallatticewasobserved.MeasurementsofthebindingenergiesoftheW47/2,C1sandO1scorelevelsindicatethatchargetransferisfromtheWtotheCandOatoms,formingW5d-C2pandW5d-O2pbonding.ThecatalyticbehaviorofthetungstencarbidesinhydrocarbonconversionreactionsismentionedandcomparedwithPtcatalysts.

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简介：Anewpolymer,polyzirconoxanesal（PZS）,issynthesizedfromthereactionofzirconiumoxychlorideoctahydrate（ZrOCl2-8H2O）withacetylacetone（Hacac）andsalicylalcohol（SA）byone-potprotocol.Thepolymerissolubleincommonorganicsolvents,suchasethanol,methanol,acetone,tetrahydrofuranandchloroform,andexhibitsrheologywithviscosityof100-300mpasat25℃.Thesepropertiesaresuitableforusesinfabricationofceramicmatrixfibercomposites.Pyrolysisofthispolymerat1300℃inargonprovidesnanosizedZrCwithsphericalmorphologyandsizeof20-100nm.

简介：高密度碳化钨nanorod数组被劈啪作响的磁控管(MS)在碳化钨nanorod数组电极上作为template.Electrocatalytic性质ofnitromethane电镀物品减小用铝格子膜(ALM)准备了被电气化学的方法调查，并且他们的电镀物品催化活性被接近到磅陪衬电极的。

简介：ElectrodeENiFe-Cland￡"4303wereselectedtojointhecementedcarbideWC-2QCoandcarbonsteel45byshieldedmetalarcweldingprocess.Microstructureandbendingpropertyofthecorrespondingjointswereanalyzed.Theresultsshowedthatthecarbonsteelelectrode￡"4303hadnopropermetallurgyconditionforthearcweldingofcementedcarbideandcarbonsteel.TheCandNicontentofthecastironelectrodeENiFe-Clcouldmeettheconditionofpreventingtheformationof7]carbide,whichwassuittothearcweldingofcementedcarbideandcarbonsteel,buttheoperationparametersneededtobeoptimizedtominimizetheslaginclusion.ThealloyWC-2QCowhichdidnotfitforcoldarcwelding,byadoptingthemeasureofbeingpreheatedat723K/or1hbeforewelding,andbeingkeptat723Kfor3hafterweldingthenfollowedfurnacecoolingcouldavoidthehappeningofcrackintheWC-20C〇basemetal.

简介：Carbidesinaseriesofcold-weldingweldmetalswerestudiedbymeansofSEM,TEMandEPMA,andtheformingmechanismofcarbidewasproposedaccordingtotheirdistributionandmorphology.Duetotheirdifferentcarbide-formingtendency,NbandTicouldcombinewithCtoformparticulatecarbideinliquidweldmetalanddepletedthecarboncontentinmatrix,whileVinducedthecarbideprecipitatedalonggrainboundary.ButtoomuchNborTialoneresultedincoarsecarbideandpoorstrengthenedmatrix.WhensuitableamountofNb,TiandVcoexistedinweldmetal,bothuniformlydistributedparticulatecarbideandwellstrengthenedmatrixcouldbeachieved.Itwasproposedthatthecarbidenucleatedontheoxidewhichdispersedinliquidweldmetal,andthengrewintomulti-layercomplexcarbideparticlesbyepitaxialgrowth.Atdifferentsites,carbideparticlesmaypresentasdifferentmorphologies.

简介：Thepaperanalysesredoxreactionsofan-tioxidantsSiandSiCeteatdifferentpositionsinthecourseofoxidationofcarbon-containingmaterials,Itispointedoutthatredoxreactionofantioxidantsinoxidized-zoneplaysaveryimportantpartinantioxidationofcarbon-con-tainingmaterials,ThereasonwhySiCcanmakecarbon-containingmaterialantioxideatthermodynamictemperaturehasbeenex-plained,Experimentprovesthatantioxidantsinoxidizedzonecanmakecarbon-containingmaterilsantioxidize.

简介：Thetheoreticalexpressionoftherelationshipbetweenoptimumdopingcontentandcrystalstructureispresentedaswellasthepreparationmethods.Byusingthisexpression,theoptimumdopingcontentofsilicon-dopedboroncarbidethinfilmiscalculated.Thequantitativecalculationvalueisconsistentwiththeexperimentalresults.Thistheoreticalexpressionisalsoappropriatetoresolvetheoptimumdopingcontentforotherelectricmaterials.

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简介：Thedefectchangesin6H-SiCafterannealingand10MeVelectronirradiationhavebeenstudiedbyusingavariable-energypositronbeam.Itwasfoundthatafterannealing,thedefectconcentrationinn-type6H-SiCdecreasedduetorecombinationwithinterstitials.Whenthesamplewasannealedat1400℃for30mininvacuum,a20-nmthicknessSilayerwasfoundonthetopoftheSiCsubstrate,thisisadirectproofoftheSiatomsdiffusingtosurfacewhenannealedathightemperaturestages.After10MeVelectronirradiation,forn-type6H-SiC,theSparameterincreasedfrom0.4739to0.4822,andtherelativepositron-trappingratewasabout27.878timesoftheoriginsample,thisshowsthattherearesomedefectscreatedinn-type6H-SiC.Forp-type6H-SiC,itisveryunclear,thismaybebecauseoftheoppositechargeofvacancydefects.

简介：氧化的本质穿cenmented的machanism碳化物工具基于热力学被学习。标准吉布斯在在不同温度切过程的可能的反应的免费精力用物质吉布斯被计算反应可能性顺序的免费精力功能方法，和顺序象每反应的特征一样被研究。理论计算显示出那WO3,公司3O4,TiO2和CoWO4是主要resultants，它与实验结果被证明。

简介：由于它的突出的电子性质，黑磷(BP)为下一代的optoelectronic设备被看作有希望的材料。在这个工作，设备基于BP/MXene(Zrn+1CnT2,T=O，F，哦，n=1，2)货车derWaals(vdW)heterostructures经由第一原则的计算被设计。Zrn+1Cn有适当工作功能的T2作文在垂直方向导致与BP的欧姆的接触的形成。低Schottky障碍在BP/Zr2CF2,BP/Zr2公司2H2,BP/Zr3C2F2,和BP/Zr3C2O2H2bilayers，并且BP/Zr3C2O2甚至展出欧姆的接触行为。BP/Zr2公司2是有type-II乐队排列的半导体的heterostructure，它便于电子洞对的分离。BP/Zr2公司2能有效地经由一个垂直电场被调节，并且BP被预言在0.4V/电场从施主经历转变到领受人。在这个工作检验的BP/MXeneheterostructures的万用的电子性质在电子学为应用加亮他们的有希望的潜力。

简介：Microstructureofthematrixdirectlyinfluencestheperformanceandtheapplicationofmetalmatrixcomposites.Byusingvacuumcasting-infiltrationmethodtomanufacturecastingtungstencarbideparticlereinforcedcomposite,theadditionofNicanalterthemicrostructureofthematrixofcomposite.Highcarbonchromiumsteelwaschosenasthesubstrate.Thecastingprocesswasachievedat1580℃withvacuumdegreeof0.072—0.078MPa.Paddingofthemoltensteelineachpartofthepreformwasdifferent,andthesolidificationofeachpartofthecompositewasdifferent,too.Microstructureofthematrixwasvariousindifferentpartsofthecomposite.TheNiadditionhadenlargedtheaustenitezoneinmatrix,whichwouldimprovethecorrosionresistanceofthecomposite.ThephaseidentificationofthecompositewasperformedbyX-raydiffractiontechnique.TheresultshowedthatFe3W3Cwastheprimaryprecipitatedcarbideanditscompositionhadadirectlinkwiththedecompositionofthecastingtungstencarbideparticles.Thehardnessofthematrixmainlydependedonthereinforcedcarbide,i.e.Fe3W3C.

简介：Alloymaterialshaveattractedincreasingattentionsbecausetheypossesssuperiorelectricalconductivitywhichcancontributetoexcellentelectrochemicalperformance.HereinadendriticNi3Calloymaterialhasbeenpreparedbythepyrolysisofnickelacetylacetonateemployingoleylamineasareductantand1-octadeceneoroctadecaneasthesolvent.Thecurrent–voltagecurvesindicatingthattheelectricalconductivityofNi3Cishigherthanthatofnickeloxide.Electrochemicaltestingindicatesthatahighspecificcapacityof390C/gisfoundinalkalineelectrolyteat0.5A/g,anddeliverexcellentratecharacteristicaswellascyclelife.Theexcellentelectrochemicalperformancemaybeattributedtoitshighelectricalconductivityanddendriticnanostructurethatcanpromotediffusionofelectrolyteions.Inaddition,theAC//Ni3Casymmetricsupercapacitorhasbeenassembledatacellvoltagesbetween0and1.6V,achievingamaximumenergydensityof37Wh/kg（atapowerdensityof0.3995kW/kg）,andthismanifeststhattheNi3Calloyisapromisingelectrodematerialforelectrochemicalenergystorage.

简介：Inthepresentstudy,amodifiedHall-Petchcorrelationonthebasisofdislocationpile-upmodelwasusedtoestimatetheyieldstrengthofSiCp/Alcomposites.TheexperimentalresultsshowthatthemodifiedHall-Petchcorrelationexpressedasσcy=244+371λ-1/2fitsverywellwiththeexperimentaldata,whichindicatedthatthestrengthincreaseofSiCp/Alcompositesmightbeduetothedirectblockingofdislocationmotionbytheparticulate-matrixinterface,namely,thedislocationpile-upisthemostpossiblestrengtheningmechanismforSiCp/Alcomposites.

简介：Continuoussiliconcarbidefiberreinforcedsiliconcarbide(SiCf/SiC)compositeshavebeenconsideredtobecandidatematerialsofhightemperaturestructuralapplicationinaerospace,energyconservationandpowergenerationduetotheexcellenthightemperaturemechanicalproperties,goodfractureresistance,corrosionresistanceandthermodynamicstability.Furthermore,duetothehighthermalstability,lowinducedradioactivity,quickdecayofactivityandlowafterheat,SiCf/SiCcompositeshavebeenrecognizedasthepromisingmaterialsoffissionandfuturefusionreactors.SiCf/SiCcompositesarecomposedofSiCfiberandSiCmarixmaterials.Radiationresistance,oxidationtolerance,fracturetoughnessandtensilestrengthofSiCfiberhaveadirectimpactontheSiCf/SiCcompositesperformance.

简介：Thetungsten-inert-gas(TIG)arcweldingexperimentsofcementedcarbideYG30andsteel45werecarriedoutusingtheNi-Fe-Cfillingalloys.Theetaphasesandmechanicalpropertiesofweldedjointswereanalyzedbymeansofscanningelectronicmicroscope(SEM),transmissionelectronicmicroscope(TEM)coupledwithselecteddiffraction,electronicprobemicroanalysisandbendingstrengthmethods.Theexperimentalresultsshowthatthechemicalcompositionofthefillingalloysaffectsetaphaseformation.Whenthecarbonandnickelcontentsinfillingalloysare0.61wt%and55.29wt%,respectively,noetaphasesform.Andthejointbendingstrengthisthehighestto1.352GPa.Butiftheyare0.01wt%and55.38wt%,theetaphasesareformedattheboundariesofthecementedcarbideandtheweld,andthethicknessofetaphaselayerisabout110micrometers.Andthejointbendingstrengthislow.Usually,theseetaphasesareanomalouslygranular,andeasytoaccumulateattheboundariesbetweencementedcarbidesandtheweld.TheyaremultipleM6Crichintungstenandiron.

简介：Electricallypumpedhighpowerterahertz(THz)emittersthatoperatedaboveroomtemperatureinapulsemodewerefabricatedfromnitrogen-dopedn-type6H-SiC.Theemissionspectrahadpeakscenteredon5THzand12THz(20meVand50meV)thatwereattributedtoradiativetransitionsofexcitonsboundtonitrogendonorimpurities.Duetotherelativelydeepbindingenergiesofthenitrogendonors,above100meV,andthehighthermalconductivityoftheSiCsubstrates,theTHzoutputpowerandoperatingtemperatureweresignificantlyhigherthanpreviousdopantbasedemitters.Withpeakappliedcurrentsofafewamperes,andatopsurfaceareaof1mm2,thedeviceemittedupto0.5mWatliquidnitrogentemperature(77K),andtensofmicrowattsupto333K.ThisresultisthehighesttemperatureofTHzemissionreportedfromimpuritybasedemitters.

简介：Thepackage36m~3/hcommercialtestunitformanufactureofacetyleneviadryCaC_2processindependentlydevelopedbytheXindouKaixingTechnologyCompanyinChenduhasbeensuccessfullydemonstrated.Thisachievementhasap-pliedforaChineseinventionpatentandapatentonpracti-calnewequipment.CurrentlytheKaixingTechnologyCom-panyisplanningtoconstructa360m~3/hdryacetylenepro-