学科分类
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180 个结果
  • 简介:AnenhancedadsorptionanddesorptionprocedureofNd(III)ontoD113-IIIresinwerepreparedwithvariouschemicalmethods.BatchstudieswerecarriedoutwithvariouspH,contacttime,temperatureandinitialconcentrations,andthencolumnstudieswereconducted.TheresultsshowedthattheoptimaladsorptionconditionwasatpHvalueof6.90.Theprocesswasfastinitiallyandarrivedequilibriumwithin60h.TheresinexhibitedahighNd(III)uptakeas232.56mg/gat298K.Theadsorptiondatafittedwellwithpseudo-second-orderkineticmodel.Thermodynamicparameterswerestudied,whichindicatedthattheadsorptionprocesswasspontaneousandendothermic.Thomasmodelwasdelineatedheretopredictthebreakthroughcurvesbasedontheexperimentalcolumnstudydata.Intheelutiontest,1mol/LHClsolutioncouldachieveasatisfactoryelutionrate,whichindicatedthatD113-IIIresincouldberegeneratedandreused.Finally,theIRspectroscopictechniquewasundertaken,andanoveladsorptionmechanismwasproposed.

  • 标签: 吸附条件 树脂 ND 水溶液 行为 红外光谱技术
  • 简介:ThemeasurementsoftemperaturedependenceofthemagneticsusceptibilityofLa1-xSrxCoO3perovskiteoxidesatdifferentSrdoping(0≤x≤0.5)andannealingtemperaturewerepresented.Forthesamplewithx=0.1,ashoulderwasobservedaround150K,andapeakwhichisonefeatureofspinglassappearedaround50Kinthecurveofsusceptibilityversustemperature.Thehigh-temperature(250~420K)susceptibilityfitswellwithCurie-Weisslawforallsamples.WeissconstantandeffectivemagneticmomentweredeterminedandtheirvariationswithSrdopingandoxygenannealingconditionwereobtained.TheWeissconstantincreasesmonotonouslywithSrcontentforx>0.2.Thevaluesofeffectivemomentswereinterpretedwiththespinstateofcobaltions.Studiesonthesusceptibilitiesofthesampleswithx=0.2underdifferentpreparationtemperaturesandannealingtemperaturesshowthattherisingofsinteringtemperatureandannealingtemperaturewillincreasethepara-ferromagnetictransitiontemperature,andreducetheeffectivemomenttonormalvalue.OurresultshowsthatbothCo3+andCo4+ionsshouldbeinISstateafterannealingandtheoxygenannealingcausesthetransitionofCo3+spinstatefromHStoIS.

  • 标签: 磁化系数 退火处理 热处理工艺 稀土
  • 简介:对八钢A高炉开炉及其生产准备经验进行了总结。由于开炉准备充分,开炉料方案制定合理,开炉操作得当,实现了顺利开炉。

  • 标签: 高炉 工序 改造
  • 简介:太钢3号高炉喷煤系统采用三罐并列、喷吹主管加分配器的喷吹形式,喷吹装置最大喷吹能力为煤比250kg/t。主要特点:三罐并列喷吹计量准确;采用浓相喷吹,实现了对氮气的回收;使用两段式喷枪、一键式全自动操作等。喷吹系统2007年8月投产,平均煤比180kg/t以上,个别月份达到200kg/t。经过两年的生产实践证明,该系统设计合理,一直处于良好的运行状态。

  • 标签: 高炉 喷煤 浓相 氮气回收 全自动操作
  • 简介:TheNd3+3.2%(atomfraction):KGd(WO4)2crystalwasgrownbyKyropoulosmethod.TheabsorptionspectrumandfluorescencespectrumofNd3+:KGWcrystalweremeasured.Theabsorptioncrosssectionsat808nm(0.6799×10-20cm2)werecalculated,andtheoutputwavelengthoffluorescenceis1064and1351nm.Thediode-pumpedlaserwasoperatedbothinthefree-runningandpassivelyQ-switchedoperatingmodes.Themaximumlaseroutput(1064nm)is326mWwith62.7%slopeefficiencywheninputenergyis900mW.ThebeamqualityfactorM2≈1.1.Thegreenlightof532nmisobtainedinfrequencydoublingoperation.ThelaserispassivelyQ-switchedbyusingCr4+:LuAGassaturableabsorber.Thepulsewidthis170nsatrepetitivefrequencyof15kHZ.

  • 标签: Nd : KGW晶体 晶体生长 LD泵浦 激光材料
  • 简介:BondedtypeRE3+dopedluminescentco-polymerwassynthesizedbysolutionfreeradicalcopolymerization.Theinfluenceofchargesequence,monomersandco-polymerizedmethodonpropertiesandstructuresoftheco-polymerswasstudied.Theemissionintensityoftheco-polymersatdifferentRE3+concentrationswastested.Theresultsshowedthattheco-polymersofEu-PStandEu-PMMAbothhadwideabsorptionpeakat200-400nmandthestrongestpeakappearedat235nm.ThefluorescentintensityofEu3+dopedpolystyreneco-polymerwasstrongerthanthatofEu3+dopedPMMAcopolymer.Thecharacteristicemissionofeuropiumionswasobservedintheco-polymers.Thecopolymerdopedwithrareearthelementsshowedthe"sensitizationeffect"forthecentralions.Thebonded-typerareearthcopolymernotonlyenhancedtheenergytransferefficiency,butalsoimprovedthefluorescenceintensitybyiacreasmgtherigidityofmainandsidechain.

  • 标签: luminescence bonded-type rare earth CO-POLYMERS RADICAL
  • 简介:Trivalentsamariumdopedbariummolybdate(BaMoO_4:Sm~(3+))redphosphorwassuccessfullysynthesizedbyhydrothermalmethod.Thecrystalstructure,morphologyandphotoluminescentpropertywerecharacterizedbyX-raydiffraction,fieldenvironmentalscanningelectronmicroscopyandphotoluminescencespectroscopy.TheresultsindicatedthatthesynthesizedBaMoO_4:Sm~(3+)phosphorconsistedofapurephasewithanoctahedralstructure.Themainexcitationpeakswerelocatedat362,404,445and477nm,respectively,andwereobviouslyobserved.Themainemissionpeakswerelocatedat533,566,602and646nm,respectively.Thephosphorsexhibitedaredperformanceat646nm,whichwasappropriatefortheultraviolet-lightemittingdiode(UV-LED)andblueLED.TheluminescentintensityofBaMoO_4:Sm~(3+)increasedwithanincreaseinthedopingamountofSm~(3+).Theluminescentintensityhadtheoptimalvalueforx=0.03.WhenthedopingamountofSm~(3+)wasfurtherincreased,theconcentrationquenchingphenomenonwasobserved.Monovalentlithium(Li+)cationwasusedasachargecompensator.TheluminescenceintensityfirstincreasedwithincreasingLi+dopingconcentration,andthendecreased.TheoptimalcontentofLi+wasabout2%.TheBaMoO_4:Sm~(3+)phosphorpreparedinthisstudycouldactassuperiorredphosphorforwhiteLEDs.

  • 标签: LUMINESCENT PHOSPHOR doping hydrothermal ultraviolet luminescence
  • 简介:YAG:Ce3+(Yttriumaluminumgarnet)fluorescencepowdersweresuccessfullypreparedbyco-precipitationmethodusingaluminumnitrate,yttriumnitrate,cerousnitrateasthestartingmaterialsandammoniumcarbonateasprecipitant.TheproductswerecharacterizedbyX-raypowderdiffraction,luminescencespectrometer,transmissionelectronmicroscope(TEM).TheXRDresultsshowedthattheobtainedYAG:Ce3+fluorescencepowdershadthecrystallinestructuresofYAGatcalcinationstemperatureof900oCandtheTEMresultsshowedthatthegraindiameterswereabout100nm.TheYAG:Ce3+fluorescencepowders,synthesizedbyco-precipitationmethod,hadthebestluminescencepropertywhentheCedopingamountwasx=0.06inthemolecularformulaofY3-xCexAl5O12,thecalcinationstimewas2handthecalcinationstemperaturewas1000°C.

  • 标签: YAG:Ce3+ POWDERS CO-PRECIPITATION method characterization LUMINESCENCE
  • 简介:TheNaGd(WO_4)_2:Eu~(3+)phosphorswerepreparedbythemicroemulsionmediatedhydrothermalmethod.ThemorphologyandsizeofthesamplescouldbedependentonthepHintheinitialsolution.Thesephosphorsobtainedhadastrongabsorptionat395nmmatchingwiththepopularemissionofnear-UVLEDchips,andcouldemitintenseredlightat616nm.Thesmallellipsoid-likeparticlesorshortrodswereprovidedwithlargeparametersofoscillatorstrength?_2andasymmetryratio.Comparedtotheellipsoid-likephosphors,therod-likephosphorstookonstrongeremission,longerlifetimeandlargerquantumefficiency.Thisworkdemonstratedthattheone-dimensionNaGd(WO_4)_2:Eu~(3+)phosphorsmightbeamorefavorabledevicethanzero-dimensiononesforphotoluminescence.

  • 标签: MICROEMULSION hydrothermal oscillator matching LIFETIME sizes
  • 简介:LiNbO3单个水晶与的生长嗯(3+)并且Zn(2+)共同做使用布里奇曼方法和它的典型吸收系列和荧光系列被报导。开始包含Zn(2+)(3%)的大尺寸的晶体并且嗯(3+)(0.6%)用象0.81.5公里·h的生长率那样的优化条件与好光质量被获得(?1)并且大约3035°C·厘米的一个温度坡度(?1)越过稳固液体的接口和封上的铂坩锅。X光检查衍射和微分热分析(DTA)被用来描绘晶体。结果显示集中嗯(3+)在晶体,他们的吸收紧张,和他们的荧光紧张的离子在晶体从底部减少到顶。为水晶的上面的部分,然而,起来变换荧光紧张比800或970nm泵激动的更低的部分的高。水晶格子,他们的结构的缺点和他们的有效分离的效果嗯(3+)离子关于起来变换荧光紧张的变化被讨论。

  • 标签: LINBO3晶体 ER^3+ ZN^2+ 共掺杂 上变频荧光性 稀土元素
  • 简介:随着闪速炉的投料量和精矿中杂质含量的逐步升高,进入余热锅炉和后续排烟系统的烟尘量也随之大幅增加,部分在余热锅炉未能硫酸盐化的烟尘,由于其粘附性较强、不易清除,在余热锅炉、鹅颈烟道、沉降室以及电收尘内大量粘结,为了确保余热锅炉和后续排烟系统的正常运转和排烟畅通,通过大量研究论证,对炉况、控制参数、物料性质、系统漏风、EF烟气等方面的控制,成功有效降低了SO,发生率。

  • 标签: 余热锅炉 排烟系统 SO3发生率 电收尘 烟尘
  • 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:Eu-activatedCaMoO4phosphorswereco-precipitatedinanaqueoussolution,andNH3·H2O,NH4HCO3and(NH2)2COaspre-cipitatingaidagentswerecomparedbasedonthemorphologyandparticlesizedistributionofthephosphorsamples.Sm3+assensitizerionwasinvestigatedontheluminescenceofCaMoO4:Eu,anditcouldstrengthenthe406nmabsorptionofthisphosphor.Atlast,thescheeliteCaMoO4:EuandwolframiteZnMoO4:Euwereselectedtocomparetheirhostabsorption.TheresultshowedthatthescheelitemolybdatehostexhibitedstrongerUVabsorptionthanwolframiteone.

  • 标签: CaMoO4 ZnMoO4 EUROPIUM SAMARIUM red PHOSPHOR
  • 简介:AseriesofMn-basedcatalysts,MnOx,MnOx-CeO2,Pd-Mn-Ce,MnOx/ACwereprepared.AndtheirperformancesforNOlow-temperatureSCRwereinvestigatedinthisstudy.TheNOconversionisabout90%at100℃onMnOx-CeO2andalmostallNOcanbeconvertedat120℃.SimilarresultsarealsoobservedinthetestsonMnOx-CeO2/AC.Theexcellentlow-temperaturecatalyticactivityofmodifiedMn-basedcatalysts,whichmaybemainlyduetotheoxygenstoragefunctionofCeO2,canimprovetheoxygenflowonthecatalystssurface.ThentheoxidationofNOtoNO2isaccelerated,whichisthekeystepofNOSCR.

  • 标签: LOW-TEMPERATURE SELECTIVE CATALYTIC reduction (SCR) NO
  • 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).

  • 标签: 光催化活性 微波辅助 ZnO 纳米棒 铕掺杂 合成技术