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  • 简介:Atemperature-inducedspinreorientationtransitionbetweenГ4(Gx,Ay,Fz)andГ2(Fx,Cy,Gz)hasbeenstudiedinthefamilyofEr1xYxFeO3(x=0,0.25,0.5,0.75,1)singlecrystals.BydopingnonmagneticY3+,wetunedthespinreorientationtemperaturetolowtemperaturewithincreasingx.Moreover,thetypicalcompensationpointandspinfliptransitionofErFeO3alsodecreaseswithdoping,anddisappearsabovex=0.75.WealsoreporttheRietveldrefinementsandRamanspectroscopyofEr1xYxFeO3,wheresomeRamanpeaksareshiftedtolowfrequencywithincreasingdoping.Ourresultsshedlightontheunderstandingoftheinteractionbetweentwomagneticsub-latticesofrareearth(R3+)andiron(Fe3+)ions,andwillalsocontributetothematerialsdesignandpotentialapplications.

  • 标签: Er1–xYxFeO3 single CRYSTAL GROWTH MAGNETIC MEASUREMENTS
  • 简介:Er~(3+)-dopedphosphor-telluriteglassforbroadbandshort-lengthEr~(3+)-dopedfiberamplifier(EDFA)isfabricatedandcharacterized.Thedifferentialvalue(△T)ofonsetcrystallinetemperature(T_x)andglasstransitiontemperature(T_g)is206°C.ThestimulatedemissioncrosssectionofEr~(a+)iscalculatedfromab-sorptionspectrumbyMcCumbertheoryandis0.87×10~(-20)cm~2at1532nm.Abroad1.5-μmfluorescencespectrumwith54-nmfull-widthathalfmaximum(FWHM)isdemonstrated.Especially,themaximumphononenergyofundopedphosphor-telluriteglassis1100cm~(-1),whichrestrictstheupconversionlumines-cence.Itispossibletopumpefficientlyat980nm.TheseresultsindicateEr~(3+)-dopedphosphor-telluriteglassissuitableforfabricatingbroadbandshort-lengthEDFA.

  • 标签: 无机发光材料 亚碲酸盐 玻璃 短距离光线放大器
  • 简介:目的探讨雌激素受体β(ERβ)及其异构体(ERβ1ERβcs)在人类表皮生长因子受体2(HER-2)阳性与阴性乳腺癌组织中的表达差异,分析其与雌激素受体α(ERα)、孕激素受体(PR)表达及临床分期和腋窝淋巴结状况的关系。方法采用简单随机抽样的方法选择中山大学附属第一医院2004年12月至2007年12月收治的HER-2高表达(卅)51例与无表达(一)53例乳腺浸润性导管癌病例,分别检测乳腺癌组织的ERα、ERβ、ERβ1ERβcx及PR表达水平,分析其相互关系及与肿瘤临床分期、腋窝淋巴结转移等临床指标的相关性。采用x^2检验对HER-2(卅)组与(一)组淋巴结表达情况进行对比分析,对HER-2(卅)及HER-2(一)组内各指标采用Spearman相关性分析。结果在HER-2(卅)与(一)两组中临床分期及淋巴结转移率差异均无统计学意义(P〉0.050);HER-2(卅)组ERα、ERβ1ERβcx、PR的阳性表达率均低于HER-2(一)组,差异均有统计学意义(P〈0.050)。HER-2(卅)组中,ERβ1ERα的表达、ERβcx与PR的表达均呈正相关(P〈0.050),但ERG、ERβ1ERβx均未显示与淋巴结转移状况及临床分期相关(P〉0.050)。HER-2(一)组中,HEβ1ERβcx的表达均与ERα、ERβ1ERβ、PR呈正相关(P〈0.050),但ERα、ERβ、ERβ1ERβcx均与淋巴结转移情况及临床分期无显著相关性(P〉0.050)。结论ERβ1ERβcx可能作为乳腺癌预后良好的指标,有必要进一步研究其与乳腺癌治疗后的生存关系。

  • 标签: 乳腺肿瘤 雌激素受体Α 雌激素受体Β 雌激素受体β1 雌激素受体βcx
  • 简介:ThemethodtopumptheFBGwrittenintoanEr3+-dopedopticalfiberisproposedtoincreasethegroupvelocityofaprobingpulsebasedonthefactsthatpump-inducedprocesschangestherefractiveindexanddispersionassociatedwiththe4I15/2-4I13/2transitioninEr3+-dopedopticalfiber.Thesystemequationsarederived.Theeffectsofpumppoweranddopingconcentrationonthegroupvelocityarediscussed.

  • 标签: 光纤 超光速传播 Bragg光波 抽吸过程
  • 简介:FrequencyupconversionofEr3+inalkalilanthanumgallateglasses(Na2O-La2O3-Ga2O3orNLG)wasinvestigated.Visibleemissionsat532,546,and660nmcorrespondingtothe2H11/2→4I15/2,4S3/2→4I15/2,and4F9/2→4I15/2transitionswereobservedundercontinuouswaveexcitationat980nm.Thequadraticpumppowerdependenceoftheseemissionsindicatedatwophotonupconversionprocess.Atapumpintensityof52W·cm-2at980nm,frequencyupconversionefficienciesof1.1×10-2and2.7×10-3wereobtainedforgreenandredemissions,respectively.

  • 标签: UPCONVERSION FLUORESCENCE GLASSES rare earths
  • 简介:Multilayerblackphosphorus(BP)nanoplateletsofdifferentthicknesseswerepreparedbytheliquidphaseexfoliationmethodanddepositedontoyttriumaluminumgarnetsubstratestoformsaturableabsorbers(SAs).Thesewerecharacterizedwithrespecttotheirthickness-dependentsaturableabsorptionpropertiesat3μm.TheBP-SAswereemployedinapassivelyQ-switchedEr:Lu2O3laserat2.84μm.ByusingBPexfoliatedindifferentsolvents,stablepulsesasshortas359nsweregeneratedatanaverageoutputpowerofupto755mW.Therepetitionrateintheexperimentwas107kHz,correspondingtoapulseenergyof7.1μJ.TheseresultsprovethatBP-SAshaveagreatpotentialforopticalmodulationinthemid-infraredrange.

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  • 简介:介绍了在液相中连续生产,-六氟丙烷(HFC236fa)和/或-氯-,3-五氟内烷(HCFC235fa)的工艺,反应中使用HCFC-235fa和/或HFC236fa作为溶剂。当反应是在SbF、SbF5或SbF5和HSOF的混合物催化剂存在下进行时,反应物料对所用容器的腐蚀非常低。

  • 标签: 六氟丙烷 五氟丙烷 连续生产 生产工艺
  • 简介:LanthanidedopedNaYF4microcrystalsweresynthesizedviaafacilehydrothermalmethod.MulticolorupconversionluminescencewasobservedinNaYF4microcrystalsdopedwithYb3+/Er3+,Yb3+/Tm3+,andYb3+/Er3+/Tm3+undertheexcitationof980nminfraredlight.Importantly,theexcitationpowerdensitydependenceofupconversionemissionintensityindicatedclearlytheenergytransferfromTm3+toEr3+ionsundertheexcitationoflowpowerdensity(5×102–9×102W/cm2).Meanwhile,theinverseenergytransferfromEr3+toTm3+ionsundertheexcitationofrelativelyhigherpowerdensity(4.1×104–4.9×104W/cm2)wasalsorevealed.ThiswasadirectevidenceforreversibleenergytransferbetweenEr3+andTm3+ions.Undertheexcitationofhighpowerdensity(4.1×104–4.9×104W/cm2),darksensitizerswerealsomotivatedsothatthebottleneckeffectofhighconcentrationYb3+iondopingwasbroken.ThiswasthemainreasonforrealizinghighupconversionefficiencyofthesampleswithheavydopingofYb3+ion.

  • 标签: 上转换发光 离子掺杂 能量转移 TM 微晶 证据
  • 简介:所有纤维基于Er~(3+):Yb~(3+)共同做在1550nm操作的两倍穿着的光纤激光器被表明。由使用9m渴望Er~(3+):Yb~(3+)共同做纤维(EYDF)著名计算机生产厂商他获得媒介,并且当波长过滤,用一双纤维布拉格栅栏,产量激光的线宽象0一样狭窄。2nm和产量力量是超过6mW。在它的排放前的激光的荧光灯的效果也被学习。并且它被发现Er~(3+):Yb~(3+)共同做双clad光纤激光器也在1080nm附近为Yb~(3+)转变展出高获得。

  • 标签: 掺杂光纤 激光纤维 BRAGG光栅 荧光效应
  • 简介:Er3+-Tm3+-Yb3+tri-dopedBaMoO4phosphorsweresynthesizedbyco-precipitationtechniqueandcharacterizedbyX-raydiffractionanalysis,absorptionstudyandfieldemissionscanningelectronmicroscopyanalysis.Upconversionaswellasdownconversionluminescencestudieswereperformedbyusingnearinfrared(980nm)andultraviolet(380nm)excitations.Energyleveldiagram,pumppowerdependenceandcolourcoordinatestudywereutilizedtodescribethemulticolorupconversionemissionproperties.Undersingle980nmdiodelaserexcitationthedualmodesensingbehaviourisrealizedviaStarksublevelsandthermallycoupledenergylevelsoftheTm3+andEr3+ionsinthepreparedtri-dopedphosphors.AcomparativefluorescenceintensityratioanalysisforintegratedemissionintensitiesarisingfromtheStarksublevels{1G4(a)and1G4(b)}andthermallycoupledenergylevels{2H11/2and4S3/2}oftheTm3+andEr3+ions,respectivelywascarriedoutinthepreparedtri-dopedBaMoO4phosphors.ThemaximumsensitivityforthermallycoupledenergylevelsoftheEr3+andStarksublevelsoftheTm3+ionwasreported.Thedevelopedphosphorscouldbeusefulinthedisplaydevicesandopticalthermometricapplications.

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  • 简介:YLiF4:Er3+wassynthesizedbyhydrothermalmethod.ConcentrationofEr3+ischangedfrom0to5%.TheabsorptionofEr3+inallsamplesfrom200to1200nmwasmeasuredatroomtemperature.TheJ-OparameterscalculatedfromabsorptionspectrumareΩ2=1.05×10-20cm2,Ω4=1.25×10-20cm2andΩ6=1.35×10-20cm2.Infrared-to-visibleupconversionemissionofYLiF4:Er3+wasobservedwhenexcitedby980nm.TheresultsshowthattheEr3+contentislessthan1.5%,excite-stateabsorptionisthemainmechanismofupconversionemission.WhenEr3+contentislargerthan1.5%,bothoftheexcite-stateabsorptionandenergytransferleadtotheupconversionluminescence.TheupconversionintensitywasenhancedwiththeincreasingofEr3+concentration.Atroomtemperature,thelifetimeof2H11/2and4S3/2is205μswhilethatof4F9/2is188μsforsampleEr-2.Thetransitionratesandquantumefficiencywerealsocalculated.Thequantumefficienciesof4S3/2and4F9/2are27.9%and10.7%,respectively.

  • 标签: 稀土 掺杂 荧光材料 YLiF4 发光性能 热液法
  • 简介:11133,3-六氟丙烷和含至少一种不饱和氟烃的混合物经蒸馏后再提纯得到11133,3-六氟丙烷含量超过99.9%、不饱和氟烃含量低于0.01%的产物。该方法为:(1)混合物与氯反应对不饱和氟烃进行饱和;(2)水洗反应混合物脱除乘余的盐酸和氯;(3)除水;(4)对反应混合物进行蒸馏得到11133,3-六氟丙烷纯度超过99.9%、不饱和氟烃含量低于0.01%的产物。

  • 标签: 1 1 1 3 3 3-六氟丙烷 致冷剂 提纯 短链氟烃
  • 简介:本发明是关于1-氯-1133,3-五氟丙烷(HCFC-235fa)的制备,HCFC-235fa是制备1113,3-五氟丙烷(HFC-245fa)的中间体。本发明还关于HFC-245fa的制备方法:包括在气相或液相中,氟化催化剂存在下,CCl3CHCCl3和HF反应生成HCFC-235fa在还原剂催化剂存在下,与氢反应生成HFC-245fa。

  • 标签: 1-氯-1 1 3 3 3-五氟丙烷 制备 氟化催化剂 卤代烃 1 1 1 3 3-五氟丙烷