简介:以EM223-16/16-DC.RLY模块元件级的维修实例,阐述了此模块的工作机制,并且通过抄板,将完整的电路图绘制下来,以便各位同行相互学习和交流。
简介:Chinaisanimportantcountryinironandsteelindustry.Powerelectronicsconvertersarewidelyused.Forthecoldrollingmillsofhighspeed,AC-DC-ACconvertersshouldbeused.Inthepaper,thedesignandthecontrolsystemofthelargepowerthree-levelAC-DC-ACconverterwithIGCTsisinvestigated,andaback-to-backlargepowerthree-levelAC-DC-ACconverterwithIGCTshasbeengot.Withaseriesexperiments,theperformanceoftheconverterisexamined.Theexperimentresultindicatestheconverterreachesthedesignrequirementanditshowsexcellentperformance.Theconvertersystemhasbeenputintousesafely.ItisestimatedthattheAC-DC-ACconvertersystemwillbeusedinthedrivesystemsforrollingmillsinthenearfuture.
简介:AluminumfilmscoatedonDIsteelsheetswerepreparedbydirectcurrent(DC)magnetronsputtering.Theinfluenceofthedepositionconditionsandfilmthicknessontheformabilityofcoatedsteelsheetswasstudied.TheresultsofthecuppingtestanddrawingtestshowthatthesubstratetemperatureandthicknessofAlfilmsarethekeyfactorsthataffectAladhesionandformabilityofcoatedsteelsheets.AdhesionbecameworsewhenthethicknessofAlsheetswasmorethan2μm.Andformabilitywasimprovedremarkablywhenthesubstratetemperaturewasincreasedto200℃.
简介:MossbauerEffectofRapidlyQuenchedAl-Fe-V-Si-MmAlloysWangJianqiang(王建强),ChaoYuesheng(晁月盛),ZengMeiguang(曾梅光),ZhangBaojin(张宝金),Ch...
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简介:采用粉末冶金法制备Cu/V0.97W0.03O2复合材料,通过场发射扫描电镜及能谱分析研究复合材料的表面形貌与成分组成,用X.ray衍射分析复合材料中各相在室温下的晶体结构,并利用涡流电导仪测试在变温过程中不同V0.97W0.03O2粉体含量的复合材料电导率的变化情况。结果表明:Cu/V0.97W0.03O2复合材料在0℃附近表现出电导率突变的特性,而且随复合材料中V0.97W0.03O2粉体添加量的增加,复合材料电导率突变的效果明显增加;同时,在室温下Cu/V0.97W0.03O2复合材料中V0.97W0.03O2的晶体结构与V02高温相的结构基本相同,说明在复合材料的烧结过程中Cu与V0.97W0.03O2的晶体结构没有相互影响,但V0.97W0.03O2有少量发生分解。
简介:Loadedonthecordierite,therareearthdopedcompositecatalystwaspreparedbysol-gelmethodcombinedwithdippingtechnique.TakingOrthodichlorobenzeneasmodel,thecatalystwasusedtoremovethedioxinsofthewastegas.Theresultsshowedthatat280℃andgasspacevelocitybeing8000h-1,theorthodichlorobenzenecouldberemovedeffectivilybythepreparedCeO2-TiO2-V2O5compositecatalystwhoseactivitywasremarkablyenhancedbythedopingofCe,whiletheindustrialside-streamtestofdioxinsfromrefuseincinerationsmokeindicatedthatthedecompositionratecouldreachabove93%underthesameconditions.
简介:Thestudyintroducesthechemicalcomposition,mechanicalproperties,physicalpropertiesandproductionprocessesoftheFe-23Mn-2Al-Vausteniticsteel.Investigationsweremadeintotheformationofcracksinthehot-rolledFe-23Mn-2Al-Vsteelplates,withopticalmicroscopy(OM),scanningelectronmicroscopy(SEM)andenergydispersivespectrum(EDS).Theresultshaveshownthatintergranularoxidationinthereheatingfurnaceisthemaincauseofthecracksonthesurfaceofthehot-rolledsteelplates.Thesurfacecrackingcanbelargelyavoidedbycontrollingtheremainingoxygencontentinthereheatingfurnaceandimprovingcontinuouscasting(CC)processestoincreasethethicknessoffineequiaxedgrainlayerofthesteelslabs.
简介:采用简单水热法和后续高温煅烧制备多孔结构V2O5微球,用X射线衍射仪分析V2O5微球的晶体结构,通过扫描电镜和透射电镜观察和分析微球表面形貌与微观结构。结果表明,微球为单相V2O5,呈形貌均一的多孔结构。作为锂离子电池正极材料,V2O5多孔微球电极在不同电压区间均显示出优异的电化学性能,在2.5~4.0V电压范围内,100mA/g的电流密度下,初始放电比容量达到145(mA·h)/g,接近理论值147(mA·h)/g,循环50圈后仍保持在138(mA·h)/g,容量保持率高达95.2%。此外,该电极还表现出优异的长循环稳定性,在2A/g的电流密度下循环1000圈后放电比容量保持在82.8(mA·h)/g,平均单圈比容量衰减率仅为0.022%。该材料优良的电化学性能得益于三维多孔微球结构。
简介:Hydrogen,asatemporaryelementintitaniumalloys,isverygoodincontrollingmicrostructure.ThemicrostructureandphasetransformationofTi6A14ValloyareaffectedbytheamountofTiH,addedintothemeltofTi6A14Valloyduringtheinductionskullmelting(ISM)process.Thisprocess,calledmelthydrogenation,wasstudiedinthispaperthroughtheuseofopticalmicroscopy,scanningelectronmicroscopy(SEM)andtransmissionelectronmicroscopy(TEM).Theresultsareasfollows:aftermelthydrogenation,boththesolidificationmacrostructureandmicrostructureofTi6A14Valloyarerefined;theαphaseprecipitatesinalamellarformwiththeresidualβphasefromthegrainboundaries;δ-hydridesprecipitateduringthesolidificationprocessasaresultoftheexistenceofhydrogen.TheSphasewithanF.C.C.structurecanbeobservedbyTEMintheαphaselaminaeofspecimenswith1.25%TiH2.Inaddition,thedependenceofthemicrohardnessofspecimensontheweightpercentageofTiH,addedtothemeltduringtheISMprocesswasalsostudied.
简介:Thesynthesis,compositionoptimization,VUVPhotoluminescence(PL)spectra,andopticalproperties,of(Y,Gd)(V,P)O4∶Eu3+phosphorswereinvestigatedbysynchrotronradiation.TheVUVPLEspectraandthecorrelationamongVUVPLintensity,λem,andEu3+,Gd3+,andP-contentwereestablished.ThePLEspectralstudiesshowedthat(Y,Gd)(V,P)O4∶Eu3+exhibitedsignificantabsorptionintheVUVrange.TheVUVPLintensitywasfoundtoenhancewithPO43-andGd3+-doping.Furthermore,thechromaticitycharacteristicsof(Y,Gd)(V,P)O4∶Eu3+werealsofoundtobe(0.6614,0.3286)andcomparedagainst(Y,Gd)BO3∶Eu3+asareference.Basedonthecharacterizationresults,wearecurrentlyimprovingandevaluatingthepotentialapplicationof(Y,Gd)(V,P)O4∶Eu3+asanewred-emittingPDPphosphor.