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1.
Thephosphorsasanimportantpartofplasmadis playpanel (PDP)deviceemitvisiblelightundervac uumultraviolet (VUV)excitationof 14 7nmand/or172nmfromXe/Hegasplasma[1] .Untilrecently ,Y2 O3∶Eu3 and (Y ,Gd)BO3∶Eu3 havebeenusedascommercialred emittingphosphorsforPDP[2 - 3] .Butthesematerialsstillhaveshortcomingstobeim proved :lowlightoutputofY2 O3∶Eu3 uponVUVex citationandbadcolorpurityof (Y ,Gd )BO3∶Eu3 [4~ 5] .AluminoborateshavestrongabsorptionintheVUVregion ,andexhibitexcellentma…  相似文献   

2.
采用X射线单晶衍射法,解析了[Ln2(CH:CHCOO)6·3H2O]·3H2O(Ln=Ce;Nd)的结构.结果表明标题化合物属同构:属单斜晶系(空间群P2(1)/c);[Ce2(CH2CHCOO)6·3H2O]·3H2O晶胞参数α=1.02099(13)nm,b=1.52294(19)nm,c=2.0325(3)nin,/3=100.838(2)°,V=3.1039(7)nm3;[Nd2(CH2CHCOO)6·3H2O]·3H2O晶胞参数α=1.01978(8)nm,6=1.50979(12)nm,c=2.02712(16)nm,β=100.881(1)°,V=3.0650(4)nm3.化合物不对称结构单元中含有两个独立的稀土中心离子,分别处九、十配位环境中.两个稀土离子由两个独立的丙烯酸μ2-氧桥联形成左手和右手螺旋链.螺旋链通过链间的水分子形成氢键网络,堆垛成三维结构.  相似文献   

3.
Inthelastfewyears ,agreatdealofworkhasbeendevotedtothemixed valencemanganitesLn1-yAyMnO3(Ln =rareearthelements ,A =Ca ,Sr ,Ba)exhibitingcolossalmagnetoresistance (CMR ) [1~ 3] .Aprominentfeatureofthesematerialsisametallic insu latingtransitionassociatedwiththeferromagnetic paramagnetictransition .Earlyworkhadrevealedthesignificanceofthedouble exchangeinteractionthroughMn3 O Mn4 networkintheclosecorrelationbe tweenthetransportandthemagnetism[4 ,5] .However ,recentdetailedstudieshaves…  相似文献   

4.
CeO2 ispresentinthemajorityoftheformulationsofthethree waycatalystsduetoitswell knownmulti pleeffectssuchas :(1)stabilizationofthepreciousmetalsdispersionandthealuminasupport[1] ,(2 )pro motionofwatergasshiftreactionandsteamreformingreaction[2 ] andsoon .TheprimaryfunctionofCeO2 intheTWCsistoprovideoxygenstoragecapacity(OSC) ,actingasanefficient“oxygenbuffer”toun dergoeffectivereduction/oxidationcyclesbyshiftingbetweenCeO2 underoxidizingconditions (oxygenstor age)andCe2 O3underreducingco…  相似文献   

5.
Compoundswiththeapatitestructureareverysuit ablehostlatticesforvariousluminescentions .ThemostwellknownexampleisSb3 andMn2 coactivatedcalci umhalophosphateCa5(PO4 ) 3(F ,Cl)∶Sb ,Mn ,whichhasfoundapplicationsinfluorescentlampsforalongtime[1] .Ca2 R8(SiO4 ) 6 O2 (R =Y ,Gd ,La)isakindofternaryrare earth metalsilicatewiththeoxyapatitestructure ,whichhasbeenusedashostmaterialsfortheluminescenceofvariousrareearthandmercury likeions[2~ 4 ] .Themostprominentstructuralcharacteristicisthetwos…  相似文献   

6.
The PDP have been widely used for large flatpanel displays.Phosphors for the application in PDPare required to have high conversion efficiency by theVUVradiation of147and/or172nmfromthe Xe andXe-He gas plasma[1].In order to have a good picturequality,much attention has been paid to i mprove ordevelop novel PDP phosphors[2~6].The commercialred emitting PDP phosphor(Y,Gd)BO3∶Eu3+showsthree sharp emissions peaked at593,612and627nm,which are corresponding to the transitions of5D0→7F1,5…  相似文献   

7.
生产低碳铝镇静钢过程中,为了控制夹杂物形态,一般要对其进行钙处理。如何使钙处理过程中生成液态的钙铝酸盐夹杂是生产控制的难点和重点。通过理论计算得出在一定条件下[Ca]-[Al]、[S]-[Al]关系图,以某低碳铝镇静钢为例,当w([Al])为0.03%时,控制w([Ca])为(9~15.8)×10-6,可以生成成分接近(CaO)12(Al2O3)7的液相夹杂。钢中w([S])为30×10-6,w([Al])为0.03%~0.04%,温度降低到1 723 K以下时,在(CaO)12(Al2O3)7上会析出CaS。  相似文献   

8.
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   

9.
李增和  朱玉俊  柳正文 《稀土》2007,28(5):72-76
采用水热法合成稀土无机有机杂化化合物[Nd(PW11O39)(H2O)3 ](H2bpy)2·4H2O.采用NdCl3·6H2O,(NH4)3PW12O40·3H2O, 4,4'-联吡啶(bpy),和去离子水(摩尔比为4∶1∶4∶3900, pH=6)在130℃下进行水热反应3天,得到标题化合物的紫红色块状晶体,并进行了红外光谱分析,元素分析.用单晶X射线衍射法测得晶体结构,属三斜晶系,空间群为P-1,晶胞参数为a=1.18824(9) nm,b =1.35707(10)nm,c=1.77691(13)nm,α=71.551(2)°,β=82.478(2)°,γ=80.568(2)°.该晶体由无机的共价链∞1[Nd(PW11O39)(H2O)3]4- 和有机的二质子化的4,4'-联吡啶(H2bpy)2 及结晶水分子堆积而成的, 是一个新的稀土磷钨酸盐无机有机杂化化合物.  相似文献   

10.
Asthebackgroundlightofhighqualityliquidcrystaldisplay (LCD) ,coldcathodefluorescentlamp(CCFL)becametheresearchemphasisalongwiththedevelopmentofthemarketofLCD .AnimportantissueagainsttheapplicationofCCFListhebrightnessandlifetimeofthephosphors .CeMgAl11O19∶Tb3 (CMAT)isaveryimportantgreen emittingphosphorfortheim provementofbrightnessofCCFL .CeMgAl11O19∶Tb3 isakindofhexagonalpoly aluminatewiththestructureasshowninFig .1.Thecrystalstructureissimilartomagnetoplumbite (idealformula…  相似文献   

11.
由三元杂多化合物 (NH4) 1 3 [Y(Si Mo1 1 O3 9) 2 ]· 36 H2 O与喹啉反应合成了电荷转移化合物 (C9H8N) 1 0(NH4) 3 [Y(Si Mo1 1 O3 9) 2 ]· 2 0 H2 O。采用元素分析、X射线粉末衍射、红外光谱、固体漫反射电子光谱进行了表征。结果表明 :喹啉通过 N原子结合质子形成阳离子与稀土杂多阴离子成盐 ,固体化合物中阴离子和阳离子之间存在较强的相互作用 ;化合物在光激发下发生分子内电荷转移 ,导致有机 C9H8N 大阳离子的氧化和稀土杂多阴离子的还原 ,标题化合物颜色由黄转变为深蓝色  相似文献   

12.
ChlorosilicatecrystalmaterialM4 Si3O8Cl4 (M =Ba ,Sr ,Ca)isasuitablehostlatticeforluminescencematerials .Adivalenteuropiumactivatedstrontiumchlorosilicatephosphorisakindofgoodblue greenemissionphotoluminescencematerialunderUVexcita tion .Itsluminescencepropertiesandcrystalstructurehavebeenintensivelystudied[1~4 ] .Inthechlorosili catehost ,theluminescenceofEu2 consistsofa4f6 5d1- 4f7(8S7/2 )broad bandemission ,whichbe longstoelectric dipoleallowedtransitionandhasthepropertiesoflargeabso…  相似文献   

13.
Preparation and Characterization ofH_7[Ga(H_2O)CoW_(11)O_(39)]·10H_2O and Its Rare EarthSalts Wang Shu-Kun(王淑坤),Wu Qing-Yin(吴庆银),Song Yu-Ling(宋玉林),Hua La(花拉)(Department of Chemistry Liaontng Untversity,Shenyang 110036,China),1993,11(1),13.Solid H_7[Ga(H_2O)CoW_(11)O_(39)]·10H_2O has firstbeen obtained by ion exchange method andLnH_4[Ga(H_2O)CoW_(11)O_(39)]·xH_2O (Ln=La~(3+),Pr~(3+).Nd~(3+),Sm~(3+)) by double decomposition,which havenot been reported so far.Their IR spectra,UV  相似文献   

14.
Recently ,manystudiesonthecompoundofLn MgB5O10 asanexcellentluminescenthosthavebeenreportedworldwidely .Variantluminescentmaterialssuchasluminescentpowders ,luminescentglasses ,lu minescentceramicandluminescentpigmentsetc ,canbeobtainedwhenLn3 ispartiallyorallreplacedbytherareearthionsofLa3 ,Ce3 ,Eu3 ,Tb3 ,Gd3 ,Pr3 ,Dy3 ionsetc ,andMg2 isreplacedbyCa2 ,Mn2 ,Zn2 ,Cd2 ions ,forexamples ,Ln1-x -yCexTbyMgB5O10 ,(CeGa) (MgCa )B5O10 ∶Mn2 and (La1-x -y GaxCey)MgB5O1…  相似文献   

15.
张婷  包燕平  崔衡  岳峰  金友林 《特殊钢》2008,29(2):60-62
洁净低碳铝镇静钢(%:0.05~0.06C、0.04Al)由210 t顶底复吹转炉-CAS精炼-连铸230 mm板坯流程冶炼.通过27~28 min CAS密封吹氩处理,钢液T[O]由CAS前(50~60)×10-6降至(19~24)×10-6,中间包钢水T[O]降至(17~20)×10-6,铸坯总氧含量为(11~15)×10-6.铸坯中主要为≤3 μm的球状、块状Al2O3和Al2O3-MnS复合夹杂.≥50μm的大型夹杂物最高含量为5.18 ms/10kg.  相似文献   

16.
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   

17.
一、前言 用钨(钼)酸盐溶液与硝酸镧溶液混合制得钨(钼)酸锎[La_2(WO_4)_3·3H_2O,La_2(MoO_4)_3·H_2O]。对合成物作了X射线分析,并研究了产物的化学性质。测得钨酸镧的溶度积Ksp=3.4×10~(-25),它的溶解度比钼酸镧小,这与文献[1、2]不同。实验结果表明,钨酸镧具有良好的离子交换性能,对Fe~(3+)和Pb~(2+)有强的亲合力。在所研究的离子中,交换能力的顺序是Fe~(3+)>Pb~(2+)>Zn~(2+)>Cu~(2+>Co~(2+)~Ni~(2+)。  相似文献   

18.
Gd2 O3isagoodhostmaterialforluminescenceandhasbeenstudiedwelltheseyears .Gd2 O3dopedwithrareearth (RE)ionsisanidealsystemforfunda mentalresearchsuchasenergytransfer[1] .Moreover ,Gd2 O3∶REhasextensiveuse .Especially ,asahighefficientred emissionluminescentmaterial ,cubicGd2 O3∶EuhasbeenwidelyusedinX rayscintillatormaterial ,highdefinitionprojectiontelevisions ,flatpaneldisplaysandphotoelectronicapparatus[2 ,3] .Inthepastcoupleofdecades ,therehasbeenadramaticgrowthofinterestinnanocrystal…  相似文献   

19.
在常规水溶液中合成了2种同多钒氧簇合物十钒酸盐[Na3(H2O)12][Ni(H2O)6]·[HV10O28](1)和[Na10(H2O)6][Co(H2O)6]·[VⅤ4VⅣ6O28](2).通过X射线单晶衍射对合成的化合物进行了表征.晶体结构分析表明:2种化合物均属单斜晶系,P2(1)群;化合物1晶胞参数a=0.902 04 nm,b=1.129 99 nm,c=1.175 15 nm,α=105.185 0°,β=97.327 0°,γ=100.838 0(10)°,V=1.114 15 nm3,Z=1;化合物2晶胞参数a=0.904 14 nm,b=1.130 84 nm,c=1.175 15 nm,α=105.18°,β=97.516 0°,γ=100.956 0(10)°,V=1.117 59 nm3,Z=1.并对2种化合物进行了磁性研究,表明磁性中心之间存在弱的反铁磁相互作用.  相似文献   

20.
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   

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