学科分类
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333 个结果
  • 简介:Glasseswiththecompositionof65GeO212Ga2O3-10BaO-8Li2O-5La2O3(molarratio)dopedwith1.526wt.%,3.006wt.%,5.836wt.%,11.028wt.%,and15.678wt.%Tm2O3,respectively,werefabricatedbyconventionalmeltingmethod.AccordingtotheabsorptionspectraandtheJudd-Ofelttheory,theJ-Ostrengthparameters(Ω24,Ω6)werecalculated,withwhichtheradiativetransitionprobabilities,branchingratiosandradiativelifetimeswereobtained.Theinfraredemissionspectra(with808nmLDexcitation)at~1.47and~1.8μmofvariousconcentrationsofTm3+-dopedglasseswerestudied.Theemissionintensityat~1.8μmreachedtothemaximumwhentheTm2O3-dopingconcentrationwasneartobe~3.006wt.%(1.0mol.%),andthendecreasedasdopingconcentrationincreasedfurther.Themechanismofthefluorescenceintensitychangewasexplainedwiththecross-relaxationeffectandtheconcentrationquenchingeffectofTm3+.Meanwhile,accordingtoMcCumbertheory,theabsorptionandemissioncross-sectionscorrespondingtothe3F43H6transitionsofTm3+at1.8μmwasobtained.ForTm3+-dopedgermanateglasses,themaximumemissioncross-sectionreachedavaluehigherthanthatre-portedforfluorozircoaluminateglasses.Itisexpectedtobeafavorablecandidatehostfor~2.0μmmid-inflatedlaserbecausetheglassshowsfavorableopticalspectra.

  • 标签: Tm3+-doped germanium-gallate GLASSES spectral properties cross
  • 简介:ThemorphologyandcorrosionbehaviorofNi/Al2O3compositecoatingspreparedusingdouble-pulsedelectrodepositingtechniqueafteroxidizedunder800℃NaCldepositinairenvironmentwereanalyzedbyscanningelectricalmicroscope(SEM),X-raydiffraction(XRD)andenergydispersivespectrum(EDS).TheresultsshowedthatthecorrosionofallcompositecoatingswasacceleratedunderNaCldeposits,andthecorrosionproductswereratherporouswithpooradherencetothematrix.Al2O3particlesinthecoatingscanrefinethegrainsizeandimprovethehightemperaturecorrosionresistanceofthecoatings.Withinthetestscope,themoreAl2O3particlesinthecoatings,thelowercorrosionratescouldbeobtained,andthecorrosionmechanismwasalsodiscussed.

  • 标签: NI/AL2O3 composite coatings ELECTRODEPOSITION NACL corrosion
  • 简介:Aseriesofnovelbluelong-lastingphosphorescencephosphorsSr6Al18Si2O37:Eu2+,RE3+(RE3+=Ho3+,Gd3+,Dy3+andPr3+)werepreparedbytheconventionalhigh-temperaturesolid-statereactioninareductiveatmosphere.TheirpropertiesweresystematicallyinvestigatedutilizingX-raydiffraction(XRD),photoluminescence,phosphorescenceandthermoluminescence(TL)spectra.ThephosphorsemittedbluelightthatwasrelatedtotheemissionofEu2+dueto5d-4ftransition.Brightbluelong-lastingphosphorescence(LLP)couldbeobservedaftertheexcitationsourcewasswitchedoff.Fortheoptimizedsample,thebluelong-lastingphosphorescencecouldlastfornearly4hinthelightperceptionofthedark-adaptedhumaneye(0.32mcd/m2).TheeffectsofRE3+ionsonphosphorescencepropertiesofthephosphorswerestudied,andtheresultsshowedthattheco-dopingofRE3+ionsgreatlyenhancedtheintensityofthepeakaround315Kwhichwasrelatedtothelonglastingphosphorescenceofthephosphorsatroomtemperatureandconsequentlyimprovedtheperformanceofthebluephosphorescencesuchasintensityandpersistenttime.

  • 标签: 荧光粉 长余辉 磷光 蓝色 发光特性 高温固相反应
  • 简介:Whitelight-emittingYVO_4:1mol.%Dy~(3+),xmol.%Eu~(3+)phosphorpowderswithordermorphologyandwellcrystallizationwerehydrothermallysynthesizedat180°C.Themicrostructure,white-lightemission,andlight-emittingmechanismofthepowderswerecarefullystudiedusingX-raydiffractometry,scanningelectronmicroscopyandphotoluminescencespectra.TheexcitationandemissionspectraofthephosphorpowdersindicatedthecoexistenceofefficientenergytransferfromEu~(3+)toDy~(3+)andinefficientenergytransferfromDy~(3+)toEu~(3+)besidestheenergytransferfromVO_4~(3–)toEu~(3+).IncreasingtheEu~(~(3+))concentrationinitiallyenhancedandthenweakenedtheluminescentintensityofDy~(3+).Thewhite-lightemissionsofYVO_4:1mol.%Dy~(3+),xmol.%Eu~(3+)phosphorpowderswerebothrelatedtotheenergytransferbetweenVO_4~(3–)andDy~(3+)/Eu~(3+),aswellasbetweenEu~(3+)andDy~(3+).TheinefficientenergytransferfromDy~(3+)toEu~(3+)wasfirstfound.

  • 标签: POWDERS PHOSPHOR DIFFRACTOMETRY coexistence luminescent excitation
  • 简介:是的Gd2O3薄电影高--门电介质被磁控管在1.3Pa和不同温度的一个压力劈啪作响在Si(001)底层上直接扔。X光检查衍射结果揭示了那从450~570慮挠牥浡捩洠瑡牥慩獬?潈?牰獥楳杮眠獡甠敳?潴映'L楲慣整愠畬業慮洠瑡楲?潣灭獯瑩獥椠?楮牴杯湥愠浴獯桰牥?牰瑯'虡N湯?楍牣獯牴'壮肭?种的所有电影湡?敭档湡捩污瀠潲数瑲敩?景琠敨挠浯潰楳整?敷敲琠獥整???慷?湩楤慣整?桴瑡琠敨戠湥楤杮猠牴湥瑧?湡?牦捡畴敲琠畯桧敮獳漠?污浵湩?慭牴硩挠牥浡捩挠浯潰楳整?楳瑮牥摥愠?????P

  • 标签: Gd2O3薄膜 电介质 稀土 磁电管
  • 简介:RE-dopedNi-basedcatalystswerepreparedbysol-gelmethod.ThesecatalystswereappliedtothereactionofCO2reformingCH4tosyngas.ThestudiesrevealthatRE-doped(RE=La,Ce,Sm,Yb)Ni-basedcatalystsshowhighercatalyticactivitythanundopedNi-basedcatalyst,andwiththeincreasingofRE-dopedquantity,thecatalyticactivityofcatalystsexhibitsregularchanges.WhenRE-dopedquantityis0.2%(molarratio),thecatalystsshowthebestcatalyticactivity.

  • 标签: DOPE BATIO3 CATALYST RARE earths
  • 简介:Awhitelong-lastingphosphorCa2MgSi2O7:Dy3+waspreparedbythesolid-statereaction.Astrongbandpeakedat260nmwasshownintheexcitationspectrumof578nmemission,whichmightbeattributedtotheoxygendeficiencyofthehost.Afterirradiatedwith254nmfor4min,thewhiteafterglowofthesamplecouldbeseenfor3h.Moreover,thedepthsandfrequencyfactorsoftrapcenterswerecal-culatedfromthethermo-luminescencecurveofthesample,whichindicatedthatthetrapcenterscorrespondingtothe414Kbandweremorehelpfultothelong-lastingphosphorescence.

  • 标签: WHITE long-lasting phosphor SILICATE DYSPROSIUM THERMO-LUMINESCENCE
  • 简介:陶器的LaNiO3样品被稳固的州的反应方法在不同sintering温度准备。这被发现结果不是ABO3perovskite单身者阶段,但是双阶段La2NiO4和NiO,和二个阶段的百分比与sintering温度变化了。在1400湩的陶艺sintered??

  • 标签: 烧结温度 电弧侵蚀 侵蚀特性 陶瓷样品 复合材料 镍酸镧
  • 简介:针对莱钢型钢炼铁厂2号炉的影响炉况顺行和高炉燃料比等多个方面进行研究,通过“开发稳定焦炭干基入炉量控制技术”、“上部实现精准布料”、“酸性料及焦丁平铺技术”等创新技术的实施,最终实现延长高炉使用寿命和低燃料比冶炼的目的.

  • 标签: 燃料比干基 入炉量 精准布料 平铺技术
  • 简介:卢本巴希8月30日消息:刚果国家矿业公司表示,2年内该公司将把铜产量提升一倍至4万吨左右。预计2006年该公司的铜产量将提升至2.2万吨左右,此前几年产量均下降。公司表示:“产量正处于上升趋势。我们希望在两年生产3万吨,甚至可能达到4万吨。”www.cnitdc.com

  • 标签: 矿业公司 年产量 刚果 上升趋势
  • 简介:有一致形态学的新奇红射出的K2(Ge,Si)F6:Mn4+黄磷被一起沉淀方法综合。纯K2有P636阶段>除P3m1空间组以外的mc空间组就被Si的加入在K2在房间温度的GeF6根据XRD描述。薄片状的显示出的SEM图象和为K2GeF6:Mn4+和K2(Ge,Si)F6:Mn4+黄磷分别地。光致发光刺激(PLE)和光致发光(PL)在K2GeF6:Mn4+和K2(Ge,Si)F6:Mn4+系统。并且K2有Si的GeF6:Mn4+显示出一座强壮的山峰。同时水晶的地包围Mn4+变化能在这个氟化物系统影响腐烂时间。带的设备的颜色范围基于K2(Ge,Si)F6:Mn4+和K2分别地,GeF6:Mn4+到达了多达94.58%NTSC(国家电视标准委员会)和94.386%NTSC那基于氮化物红黄磷比那高得多。在K2(Ge,Si)F6:Mn4+黄磷的所有这些原来的特征作为为改善灯光和常规白LEDs的显示质量的红黄磷为潜在的应用是合乎需要的。

  • 标签: 红色荧光粉 白光LED SI Ge 发光性能 合成
  • 简介:(Y,Gd)BxV1-xO4-x:Eu3+phosphorswerepreparedbysolidstatereaction.Theredemissioncolorpurityof(Y,Gd)BxV1-xO4-x:Eu3+phosphorismuchbetterthanthatoftherecentwidely-usedcommercialredemittingphosphor(Y,Gd)BO3:Eu3+anditsrelativeemissionintensityis84%ofthecommercialphosphor(Y,Gd)BO3:Eu3+.Itisexpectedthat(Y,Gd)BxV1-xO4:Eu3+phosphorwillbeapromisingcandidateforPDP(plasmadisplaypanels)application.

  • 标签: PDP (Y Gd)BxVi-xO4-x:Eu3+ PHOSPHOR photoluminescence rare
  • 简介:La1.5Mg17Ni0.5hydrogenstoragematerialswerepreparedbyhydridingcombustionsynthesis(HCS)andmechanicalalloying(MA)methodrespectively.TheexperimentalresultsshowthatthehydrogenabsorptionpropertiesofLa1.5Mg17Nio.5preparedbyMAarebetterthanthatbyHCS.La1.5Mg17Nio.5preparedbyMAcanabsorb6.73mass%hydrogenat523Kwithin1min,and4.92mass%hydrogenat423K.TheimprovementofhydridingpropertiesofLa1.5Mg17Ni0.5alloypreparedbyMAcanbeascribedtotheformationofnano-crystallineanddefectsduringthemechanicalalloying.

  • 标签: HYDRIDING COMBUSTION synthesis mechanical ALLOYING hydrogen
  • 简介:AseriesofSm~(3+)dopedY_2MoO_6werepreparedthroughhightemperaturesolidstatereactiontechnique.Theirphasestructures,morphologiesandluminescencepropertieswereinvestigatedbyX-raydiffraction(XRD),scanningelectronmicroscopy(SEM)andphotoluminescencespectrometry.ThemostintenseabsorptionofY_2MoO_6hostoccurredat367nm.EnergytransferfromhostlatticetoSm~(3+)ionscouldbeobserved,andtheschematicdiagramofenergytransferwasconstructed.ThecriticalenergytransferdistanceandenergytransfermechanismbetweenSm~(3+)ionswerediscussedindetail.Consideringthehighcolorpurityandappropriateemissionintensity,Sm~(3+)dopedY_2MoO_6couldbeapromisingphosphorundernearultravioletlightexcitation.

  • 标签: 紫外光激发 荧光粉 相结构 发光性能 掺杂 能量传递机理
  • 简介:Thesolutionreactionmechanisms,composition,donoratoms,propertiesofcoordinatelinkandstabilityofthecomplexesonthesystemsofadrenalinewithNa3+,Gd3+andTm3+havebeenstudiedbypH-potentiometrictitrationandelectronicspectroscopy.Adrenalineperturbsthef-felectronictransitionofNd3+andTm3+sothattheabsorptionspectraoftheircomplexesareshiftedtowardlongerwavelengths.Theabsorptionspectraofthecomplexesformedbythethreef-blockelementionswithadrenalineareshiftedtowardshorterwavelengthswiththeincreaseofPHinΔγ=350~650nm

  • 标签: ADRENALINE NEODYMIUM GADOLINIUM THULIUM Solution EQUILIBRIUM
  • 简介:DifferentphasesofMg-Li-SmalloyswerepreparedbygalvanostaticelectrolysisinLiCl-KCl-MgCl2-SmCl3meltsat670°C.TheelectrolysisprocessandphasecontrolofMg-Li-Smalloyswerestudied.Themicrostructuresofα,α+β,βphasesofMg-Li-SmalloyswerecharacterizedbyX-raydiffraction(XRD)andopticalmicroscope(OM).Analysisofscanningelectronmicroscopy(SEM)andEDSmappinganalysisshowedthatMgdistributedhomogeneouslyinMg-Li-Smalloys.EDSresultshowedthatthedistributionofSmwasmoreat...

  • 标签: Mg-Li-RE ALLOYS ELECTRODEPOSITION molten salt rare