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1.
BaFBr∶Eu2 +,asphoto gatedholeburningmateri al[1] ,scintillatorcrystallinematerialandX rayimagestoragematerial ,iscalledphotostimulatedluminescence(PSL)material[2 ] .Theimagingplate (IP)madeofthesephosphorsisnowusedwidelyasdisplayoftwo dimen sionalimagescausedbyionizationradiation[3] .Thecommercialapplicationofthesematerialsbe ganin 1983.Becauseofapplicationofthesephospho rs ,theconventionalX rayfilmmaybereplacedbythescreenmadeofPSLphosphors (alsocalledimagingplate ,IP) [4 ] .IPhasnotab… 相似文献
2.
Gd2 O3∶Eu3+ isanefficientredemittinglumines centmaterial ,whichcanbeappliedindisplays[1,2 ] .TheconventionalcommercialGd2 O3∶Eu3+ ismainlysynthesizedbyhightemperaturesolid statereactionandchemicalco precipitationmethods .Anadvancedperformanceofdisplaysrequireshighqualityphospho rssuchashighbrightnessandefficiency ,monodisper sityandfinegrainsize .Muchresearchhasanticipatedthatsubmicrometer sizedandnanometerluminescentmaterialswillhavethesepotentialadvantages[3~ 8] ,sosubmicrometer sizedan… 相似文献
3.
Preparation of Stable CaS∶Eu~(2+), Tm~(3+) Phosphor 总被引:1,自引:0,他引:1
Alkalineearthsulfides (AES)havebeenfoundtobeexcellentandversatilephosphor ,andrareearthsasactivatorshavebeenintensivelyinvestigated[1~ 7] .Theyholdpromiseforapplicationsinphoto ,electro ,cathoderay ,fieldemissiondisplaysandluminescencepaints[8,9] .However ,alkalineearthsulfidesasaphos phorhosthavebeenfoundtobelimitedinapplica tion ,duemainlytoitssensitivetomoistureandotheratmosphericcomponents .Theirchemicalstabilityagainstatmosphericcarbondioxideandmoisturecouldbeenhancedthroughthegoodcryst… 相似文献
4.
Oxidation of Al2O3-30%TiCN-0.2%Y2O3 Composite 总被引:3,自引:0,他引:3
Thecuttingtoolmaterialshavegoodoxidationre sistance ,buttheyareoxidizedathightemperature(about 10 0 0℃ )duringoperation .Themechanicalpropertyofthecuttingtoolmaterialswillbechange d[1,2 ] .Therefore ,researchonoxidationbehaviorofcuttingtoolsmaterialsathi… 相似文献
5.
《工程科学学报》2015,(8)
采用同时平衡和质量守恒原理对全液相常温常压法制备CuInSe2(CIS)粉体过程中Cu+-In3+-Se2--NH3-L2--Cl--H2O体系的热力学平衡进行分析,并绘制一系列的浓度对数lgc-p H值曲线.依据平衡图,发现溶液中[NH3]T的变化主要影响溶液中[Cu+]T在体系中的浓度变化,[L2-]T的变化主要影响的是体系中[In3+]T的浓度变化,而[Cl-]T的变化对[Cu+]T和[In3+]T的浓度变化均有影响,并可发现在pH 7.0~8.5时沉淀率最高.依据Cu+-In3+-Se2--NH3-L2--Cl--H2O体系的同时平衡和质量守恒原理,采用全液相常温常压法,在pH 7.0~8.5条件下制备出粒径在20~50 nm且基本符合标准化学计量比的CIS纳米粉体. 相似文献
6.
Inrecentyears ,SrAl2 O4 ∶Eu2 ,Dy3 ,CaAl2 O4 ∶Eu2 ,Nd3 [1~ 8] andBaAl2 O4 ∶Eu2 ,Dy3 [9]havebeenconsideredasusefulblueandgreenphos phorsbytheirlongdurationphosphorescence .Howev er ,toourknowledge ,thephosphorBa1-xCaxAl2 O4 ∶Eu2 ,Dy3 hasnotbeeninvestigated .TheluminescenceofEu2 isverystronglydepen dentonthehostlattice ,whichcanoccurfromtheul traviolettotheredregionoftheelectromagneticspec trum .Itiswellknownthatthepersistentluminescenceisduetothetrappingofenergyinthed… 相似文献
7.
Long lastingphosphorescence(LLP)isaproper tyofphosphorswithlongdecaytime,rangingfroma fewminutestotensofhours[1].Inrecentyears,LLP materialshavebeenwidelyusedinmanyfieldssuch asroadsigns,emergencylighting,graphicarts,inte riordecoration,automobileinstrument,andoptical datastorage[2~4].Buttodate,theprogressonred phosphorescenceisveryslow.TheredLLPmaterialbasedonsulfide(CaS∶Eu3+)hasnearly3hafterglow.However,itisex tremelysensitivetomoistureandthuschemicallyun stable[5].CaTiO3∶Pr3+,BaT… 相似文献
8.
Duringlastdecade ,manyresearchershaveshowngreatinterestinluminescencepropertiesofcompoundscontainingM4 ions (M =Ti ,ZrandHf)withtheclosed shell (nd0 )becausetheyhavemorepracticalandpotentialapplications ,suchasphosphorusedinX rayintensifyingscreenandapromisingmaterialap pliedinfracturedetectionsystemofstructureceramicsinthefieldofengineeringmaterials[1,2 ] .Theopticaltransitionsinthesecompoundsareoftheligand -to -metalchargetransfer (LMCT)type .WithinthemtheZr4 -O2 chargetransfertran… 相似文献
9.
Thesolidelectrolyteisakeycomponentofsolidoxidefuelcell (SOFC) .Dopedceriaisoneofpromis inghigh conductingsolidelectrolyteinSOFC[1,2 ] .Butitiswell knownthatitisdifficulttosinterdopedceriabysolidstatereactioninair .TheCe0 .9RE0 .1O2 -δelectrolytematerialswerepreparedbythesol gelmethod .Thesinteringtemperatureofthesamplescandecreasetoabout 4 0 0K .Theionicconductivityandlinearthermalexpansionpropertiesofsol gelpreparedCe0 .9RE0 .1O2 -δinawidetemperaturerangewerein vestigated .Thepowder… 相似文献
10.
以Sr2+,Y3+和Eu3+的混合硝酸盐溶液为阳离子溶液,以(NH4)2CO3为沉淀剂,共沉淀法制备了碳酸盐前驱体,TG-DSC分析结果表明,随着(NH4)2CO3浓度的升高,前驱体组成由碱式碳酸盐向正盐转变。以CS2为硫化剂,高温煅烧前驱体合成了SrY2S4∶Eu2+红色荧光粉。XRD表明前驱体经800℃处理得到纯相SrY2S4。荧光光谱和SEM研究表明在[Sr(NO3)2+Eu(NO3)3]∶[Y(NO3)3]∶[(NH4)2CO3]=0.25∶0.50∶2.00(摩尔比)条件下制备前驱体,然后1050℃煅烧4 h所得荧光粉的发光强度最大,粒径小于1μm,粒子形貌呈椭球。Eu2+在SrY2S4基质中的最佳掺杂摩尔分数是0.6%。 相似文献
11.
12.
Texture of Nanocomposite Nd2Fe14B/α-Fe Melt Spun Ribbons 总被引:3,自引:0,他引:3
Inrecentyears ,Nd2 Fe14 B/αFenanocompositemagnetshaveattractedconsiderableinterestbecauseoftheirfavorablelowcostandhighpotentialenergyprod ucts.However ,thehighestmaximumenergyproduct(BH) maxobtainedinlaboratoryisonly 1 85kJ·m- 3tillnow[1] ,whichisfarlowerthanthetheoreticvalue ,80 0kJ·m- 3[2 ] .Severalexchangingcouplingmod els[3,4 ] predictedthatfurtherincreaseof (BH ) maxshouldcomefromtheimprovementofmicrostructure ,suchasfinergrains ,morehomogeneousphasedistri butionandpreferentiallyo… 相似文献
13.
60Si2CrVAT弹簧钢EAF-LF(VD)-CC工艺实践 总被引:6,自引:1,他引:5
用 10 0tUHPEAF +LF(VD) + 30 0mm方CC工艺生产提速铁路车辆用弹簧钢 6 0Si2CrVAT的工艺实践表明 ,钢的清洁度为 [O]10× 10 - 6 ,S 0 .0 0 5 % ,P 0 .0 12 % ,连铸时用结晶器 +凝固末端电磁搅拌 ,使连铸坯中心碳偏析指数达 1.0 8。 相似文献
14.
Effect of Multiple Alloying Elements on Microstructure and Magnetic Properties of Nanocomposite Nd2Fe14B/α-Fe Magnets 总被引:1,自引:0,他引:1
TheappearanceofnanocompositemagnetsbroketheremanencelimitpredictedbyStoner Wolhfarthmodethattheremanenceofisotropicmagnetwouldnotexceedhalfofitssaturationmagnetization[1] .Accord ingtoSkomski′scalculation[2 ] ,highmaximalenergyproduct (BH) maxof 80 0kJ·m-3 couldbeachievedinNd2 Fe14 B α FenanocompositewhentheaveragegrainsizeofNd2 Fe14 Bisrefinedtoabout 2 0nmandthatofα Fetoabout 10nm ,becauseoftheeffectofrema nenceenhancement (Mr Ms >0 .5 ) .Unfortunately ,thereported (BH) max(185kJ·… 相似文献
15.
TiO2 andCeO2 aresemiconductormaterials .TiO2hasthepropertiesofphoto catalysis[1] whileCeO2 hastheabilityofoxygenstorageandcanpromotethedispersionofprecionsmetalsonthesupporter[2 ] .CeO2 TiO2 com plexcompoundwasusedascatalystandspecialfunction almaterial[3~ 5] .ThetraditionalsynthesisofCeO2 TiO2complexcompoundisbyceramicmethodthatusesoxidesasrawmaterialsanditiscalcinedabove 130 0℃[6~ 8] .However ,thestructureandmicrostructureofthecomplexcompoundarenotsuitableforcatalystandfunctionalm… 相似文献
16.
Longphosphorescencephosphorshaveattractedconsiderableattentioninrecenthalf century[1] becauseoftheirpotentialapplicationsinsuchfieldsaslumi nouspaint ,safetyindicatorinemergencycase ,etc[2~ 4 ] .Sincethediscoveryofalkali earthaluminatelonglastingphosphorsin 1996 [1] ,theyhavebeenstudiedextensivelyastheyhavebetterstabilityandlongerpersistenttimethanthesulfidephosphorswhichwerewidelyusedinmanycases .Uptonow ,poly crystallinephosphorsofblueCaAl2 O4 ∶ (Eu2 ,Nd3 ) ,greenSrAl2 O4 ∶(Eu2 ,… 相似文献
17.
Yuan Jianhui 《中国稀土学报(英文版)》2005,(4)
Effects of Doping Trace Sm~(3+) and Gd~(3+) on Luminescent Character of Y_2O_2S∶Eu~(3+) 相似文献
18.
Fluorescence spectra of Sm~(2+)and Eu~(2+)→Sm~(2+)energy transfer were studied in SrB_4O_7.There appearsonly fluorescence from ~5D_0 transition of Sm~2+ at 77 K.The vibronic lines associated with ~5D_0→~7F_0 transitionwere observed.The thermal population to upper states of ~5D_1 and 4f~5d levels from ~5D_0 gives rise to ~5D_1→~7F_J and 5d→4f radiative transitions of Sin~(2+)at higher temperature. 相似文献
19.
Animportantclassoffluorescentlampandplasmadisplayphosphorsisbasedoncom poundsofthealkaliearth rareearthaluminatesystemsbecauseoftheirhighluminescenteffi ciencyandstabilityunderultravioletandvacu umultravioletlightexcitation[1] .Especially ,alkalineearthhe… 相似文献
20.
H2 Sisakindofdeadlypoisonousgaswhichex istsextensivelyinpetroleumandchemicalengineeringproductionline .Itsmassconcentrationintheairisre strictedbelow 0 .0 1mg·dm- 3inindustry (≈ 7× 10 - 4volumefraction) [1] .AcertainquantityofH2 SintheLPG (liquefiedpetroleumgas)resultsinthecontainerinvalidatingeasily (Nationalstandardisthatthecon tentofH2 SintheLPGcannotexceed 340× 10 - 6 vol umefraction) [2 ] .ThecontentofH2 Sinsomemineraldepositsisinconnectionwiththetypeofmineralde posits[3] ,soitc… 相似文献