简介:有一般公式的1,10-phenanthroline(phen)的铈,镨和钕的硝酸盐建筑群[行(phen)2(NO3)2(H2O)2]·NO3(在哪儿,Ln=Ce,Pr和Nd)被X光检查晶体学准备并且描绘。这些建筑群的Thermolysis被同时的thermogravimetry(TG)和微分热分析(DTA)调查。等温的TG被拿用模型适合评估运动参数以及为免费isoconversional方法建模。thermolytic小径也被建议,它包含点火跟随的分解。所有三建筑群有第十期协作并且显示出multistep分解。以便评估快速的加热的反应,点火延期(Di)大小被承担。为点火的激活精力被发现在顺序减少:Nd>Pr>Ce。
简介:InordertoimprovethecorrosionandmechanicalpropertiesofAM50magnesiumalloy,1wt.%GdwasusedtomodifytheAM50magnesiumalloy.Themicrostructure,corrosionandmechanicalpropertieswereevaluatedbyX-raydiffraction(XRD),scanningelectronmicroscopy(SEM),energydispersivespectroscopy(EDS),electrochemicalandmechanicalstretchmethods.Theresultsindicatedthatβ-Mg17Al12phasedecreasedandAl2Gd3andAl0.4GdMn1.6phaseexistedafterGdaddition.BecauseoftheGdaddition,thegrainofAM50magnesiumalloywasrefinedsignificantly,whichimprovedthetensilestrengthofAM50magnesiumalloy.Thedecreasingofβphaseimprovedthecorrosionresistanceofthemagnesiumalloy.ThefracturemechanismoftheGdmodifiedAM50magnesiumalloywasquasi-cleavagefracture.Thecorrosionresidualstrength(CRS)ofAM50magnesiumalloywasimprovedafter1wt.%Gdaddition.
简介:Eu3+activatedSr1–xEuxZrO3(x=0.01–0.04)phosphorwithperovskitestructurewassuccessfullysynthesizedbyusingcombustionmethod.Thestructure,morphologyandopticalpropertiesofthematerialwerecharacterizedbyX-raydiffraction,scanningelectronmicroscopyandfluorescencespectrometry.TheXRDresultsindicatedthatcrystalsofSrZrO3:Eu3+belongstotetragonalperovskitesystem.ThephosphorcouldbeeffectivelyexcitedbyUVlightandtheemissionspectraresultsindicatedthatreddish-orangeluminescenceofSrZrO3:Eu3+duetomagneticdipoletransition5D0→7F1at593nmwasdominant.Thus,thepreparedphosphorshowedremarkableluminescentpropertieswhichfindapplicationsinfieldemissiondisplay(FED)andplasmadisplaypanel(PDP)devices.
简介:Eu3+/Sm3+codopedBiPO4黄磷与没有表面活化剂的环境经由一个灵巧的热水的方法被综合。X光检查衍射分析证明样品拥有了标准BiPO4单斜晶的结构。扫描电子显微镜学图象证明所有样品与像梭的形状分散得好的、测微计大小的晶体创作了。到Eu3+的从Sm3+的精力转移被光系列和Sm3+4G5/26H5/2排放的腐烂过程证实。橘子红光能在Eu3+/Sm3+codopedBiPO4黄磷被获得。Sm3+4G5/26H5/2排放的平均一生在BiPO4:0.03Sm3+在BiPO4:0.03Sm3+从2.70ms减少了到2.37ms,0.05Eu3+。在395nm附近的强壮、宽的吸收乐队,从Eu3+的7F05L6转变和Sm3+的6H5/24K11/2转变发源,资助BiPO4:Eu3+,有近紫外激动的white-light-emitting二极管的域里的潜在的应用程序的Sm3+黄磷。
简介:Eu2+andDy3+codoped(Ca,Sr)7(SiO3)6Cl2yellowphosphorsweresuccessfullysynthesizedbyself-fluxmethod.Thestructure,morphologyandphotoluminescencepropertieswereinvestigatedbyX-raydiffraction(XRD),scanningelectronmicroscopy(SEM)andphotoluminescencespectra.Theas-preparedphosphorshowedabroademissionspectrumcenteredat550nmforEu2+single-dopedphosphor,whilelocatedat548–544nmfortheEu2+,Dy3+codopedsamplesunderexcitationat380nmlight.TheemissionintensitywasgreatlyimprovedwhenDy3+wasdopedintothe(Ca,Sr)7(SiO3)6Cl2:Eu2+system.Thecomposition-optimizedsamplewith3mol.%ofDy3+andconstant10mol.%ofEu2+exhibiteda220%PLenhancementcomparedtothephosphorwith10mol.%Eu2+single-doped.Meanwhile,itwasfoundthatthequantumefficiencyofphosphornamely(Ca,Sr)7(SiO3)6Cl2:3mol.%Dy3+,10mol.%Eu2+couldgetupto24.6%.Thesynthesizedyellow-emitting(Ca,Sr)7(SiO3)6Cl2:Dy3+,Eu2+isapromisingcandidateashigh-efficiencyyellowphosphorforNUV-excitedwhiteLEDs.
简介:Ceriasphereswithdifferentsizesandsulfurizedproductswithcorrespondingmorphologywerepreparedbyhydrothermalandgas-solidreactionmethodat600–800°CunderCS2atmosphereforashorttime,respectively.Dimensionaleffectinpreparationofγ-Ce2S3wasfirstlyinvestigatedbymeansoftechniquessuchasscanningelectronmicroscopy(SEM),X-raydiffraction(XRD),thermalgravimetricanalysis(TGA)andspectrophotometer.Theresultsshowedthatwhenceriananoparticleswithsmallsizewereusedasprecursors,theγ-Ce2S3couldbepreparedatthelowertemperatureandthebadlysinteredproductswereobtained;whenceriananoparticleswithlargesizewereemployedasprecursors,pureγ-Ce2S3wasdifficultlyobtainedevenifthetemperaturewasupto800°Candtheproductstendedtokeeptheiroriginalsize.Theheat-resistancepropertyoftheγ-Ce2S3withlargesizewasbetterthanthesmallerone,andthepureγ-Ce2S3preparedfromprecursorwithsmallsizehadagoodpigmentaryperformance.
简介:ThedopedZnOnanorodsasaphotocatalystwithdifferentEucontentswerepreparedbymicrowaveassistedmethodandtheywerecharacterizedbymeansofX-raydiffraction(XRD),energy-dispersiveX-rayspectroscopy(EDS),UV-Visspectroscopy,surfaceareaBrunauer-Emmett-Teller(BET),X-rayphotoelectronspectroscopy(XPS),scanningelectronmicroscopy(SEM)andtransmissionelectronmicroscopy(TEM).TheaveragecrystallitesizeandbandgapenergyofEu-dopedZnOwerevariedwiththeEucontent.TheXRDpatternofEu-dopedZnOindicatedhexagonalcrystalstructurewithanaveragecrystallitesizeof25nm.ThepresenceofeuropiumwithtrivalentstateanditsdopingsuccessfullyintothecrystallatticeofZnOmatrixwereconfirmedbyXPStechnique.ThephotocatalyticactivityofEu-dopedZnOnanorodswasevaluatedformethylorangedegradation.Thephotocatalyticexperimentsshowed~91%degradationofmethylorangeover0.2mol.%EudopedZnOsamplewithin3hunderUVlight(365nm).
简介:SmOHCO3micro/nanoparticleswerepreparedinwater/oil(W/O)reversemicroemulsioncomposedofcetyltrimethylammoniumbromide(CTAB),n-octane,n-butanol,Sm(NO3)3·6H2Oandureaaqueoussolutionbythecouplingrouteofhomogeneousprecipitationwithmicroemulsion.ThenanoparticleswerecharacterizedandanalyzedbyX-raypowderdiffraction(XRD),thermalgravimetricanddifferentialthermalgravimetricanalysis(TG-DTG),Fouriertransforminfraredabsorptionspectra(FT-IR)andscanningelectronmicroscope(SEM).TheresultsshowedthatthephaseSmOHCO3micro/nanoparticleswasinagreementwithpureorthorhombicphase.ThedifferentmorphologiesofSmOHCO3micro/nanoparticleswithgoodmonodispersityandsizewereobtainedbyregulatingthereactiontemperatureandreactiontime.PossibleformationmechanismsofthemorphologicalstructureofSmOHCO3wereproposedanddiscussed.
简介:结合实例,分析数控车削加工中的基本工艺、机床坐标系和工件坐标系的建立问题;针对FANUC0i系统数控车床的对刀法,阐述了多把刀具的对刀步骤;并对零件进行了手动程序编制.