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203 个结果
  • 简介:OpticalabsorptionandemissionintensitiesofNd3+ioninKLu(WO4)2crystalwereinvestigated.BasedontheJudd-Offelttheory,wecalculatedthefollowingspectralparameters:phenomenologicalintensityparametersΩ2=5.567×10–20,Ω4=3.597×10–20,andΩ6=3.800×10–20cm2.Theradiativelifetimeoflevels4F3/2was182.58μs.Thefluorescencebranchingratioforthetransition4F3/2→4I11/2was46.98%.Inaddition,theradiativetransitionprobabilitiesAJ,J’,oscillatorstrengthsPJ,J’andthevaluesofinte...

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  • 简介:AsystematicinvestigationofthemagneticandtransportpropertiesofTidopedLa0.67Ca0.33MnO3wasreported.TheTisubstitutionforMnionsresultsinareductioninferromagnetismandconductivity.Themetal-insulatortransitiontemperatureisclosetoCurietemperaturewhichdecreasesfrom274to82Kasxincreasesfrom0to0.17.ThemostimportanteffectofTidopingistointroducespinclustersinthesamplesduetothedistortionoflocallatticeandtheinhomogeneousmagneticstructureinducedprimarilybytherandomdistributionofMnions.Amaximummagnetoresistanceratioaslargeas90%in1Tat122Kwasobtainedforthesamplewithx=0.055,whichisfourtimeslargerthanthatobtainedforLCMOsampleat272K.Thereisaremarkablefield-historydependentMRinthecoolingprocessforthedopedsampleswhilesuchphenomenondisappearsinthewarmingrun.Theresistivityfollowswellthevariablerangehoppingbehaviorinparamagneticstate.Boththesizeeffectandspindependenthoppingofcarriersbetweenthespinclustersshouldbeconsideredinthissystem.

  • 标签: 瓷器材料 磁阻效应 稀土元素
  • 简介:Au/TbMnO3/YBa2Cu3O7-xcapacitorswerefabricatedonSrTiO3substratesbypulselaserdepositiontechnique,ofwhichelectricpropertieswereinvestigatedinthetemperaturerangefrom25to300K.Bothcurrent-voltagecharacteristicsandjunctionresistanceswithbiasvoltagesshowedremarkabletemperaturedependence,inwhichobviousthermallyexcitedrelaxationprocesseswerefoundbetween150and200K.Atthetemperatureslowerthantheactivationprocess,theleakagecurrentsofthecapacitorswerestudied.Interestingly,athighelectricfield,themechanismoftheleakagewasPoole-Frenkelemission.However,atlowelectricfield,theconductionwasnotOhmic,andideallnJ∝E1/4characteristicswereobserved.Analysisshowedthatthepossibleoriginwasrelatedtotheinherentinhomogeneousnatureofactivationlesspercolatingtransport.

  • 标签: 低电场 电荷载体 运输 脉冲激光沉积技术 电影 低温
  • 简介:经过充分地分析和论证两座300m~3级高炉1997年一季度炉况顺行差、经济技术指标不好的原因,决定采用蒸汽加湿鼓风技术,并针对以前加湿操作的不足之处,做了改进和完善,运行实践证明:此项技术使炉况顺利明显改善,并获得增产,节焦和铁水质量提高的良好效果。

  • 标签: 加湿鼓风 300m~3高炉 应用
  • 简介:Thenanosizedparticlematerialsofdoped-TiO2withY2O3werepreparedbymeansofsol-geltechniqueforuseinelectrorheological(ER)fluids,andtheircrystalstructuresweremeasuredbyX-raydiffraction(XRD)analysis.TocomparewiththepureTiO2,adistinctenhancementintheshearstressunderdcelectricfieldwasfoundbyusingsuchmaterials.Thiscanbeexplainedbytheincreaseofthedielectriclossanddielectricconstantatlowfrequency.TheeffectsofthecrystalstructureoftheparticlesonthedielectricpropertyandERperformanceofmaterialswereinvestigated.

  • 标签: 二氧化钛 纳米材料 掺杂 稀土 XRD 结构
  • 简介:高度有效的Tb3+激活SrAl2O4黄磷被一个联合combustionsolid状态反应方法综合。SrAl2O4的先锋:Tb3+黄磷经由一个燃烧过程被准备,然后同样准备的粉末被加热在一减少在1250点的激活的碳周围??慥獲?

  • 标签: 燃烧分析 SrAl2O4: TB^3+ 结晶度 稀土
  • 简介:详细介绍了烧结矿分级入炉技术在太钢中使用的工艺流程以及在使用后高炉的调剂方法及效果.实践表明,此技术的应用丰富了高炉操作调剂手段,并在节能降耗和降低生铁成本上有良好的效果.

  • 标签: 分级入炉 煤气流调剂 合理操作炉型 降本
  • 简介:通过对该高炉计控功能提出的要求,介绍该高炉过程检测与控制系统的设计要点,并对集散系统的选型作了必要的阐述。

  • 标签: 集散控制系统 计控功能 选型
  • 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:由十二冶编写的《法兰喷涂的辅助装置》、《加工方法兰车床用夹具》和《桅杆式起重机》3项实用新型专利获得国家知识产权局的专利授权,还有9项专利正在受理之中。十二冶此次获得专利授权,标志着该公司知识产权保护取得了新的突破。近年来,十二冶大力加强科技创新,不断健全科技创新组织体系、研发体系和支撑体系,加大科技投入,建立公司科技工作专项资金库,保障了科技工作的顺利开展。广大科技工作者和一线员工在技术研发、提升技术装备水平、“四新”技术应用、QC活动、工程项目创优和职工合理化建议等方面下功夫,有效推进了原始创新和技术革新。

  • 标签: 国家知识产权局 专利授权 科技工作者 技术革新 实用新型专利 桅杆式起重机
  • 简介:针对太钢4350m3高炉水渣系统皮带机头轮吹扫装置在生产过程中暴露出来的能耗较高的问题,对其机械结构进行降耗改造.根据实际生产设备,运用三维建模软件对其结构进行建模,给出了改造部位的结构模型图,并且已经运用到实际生产中.实践证明,这次技术改造不仅大大降低了能源消耗,直接降低了生产成本,而且提高了吹扫冲渣的能力.

  • 标签: 皮带机吹扫装置 节能 降本增效 三维建模
  • 简介:日前,西南铝顺利通过了重庆市环境保护局的复查,继续保持了“重庆市环境友好企业”的称号。这是西南铝自2006年成为首批“重庆市环境友好企业”后连续3年保持这一殊荣。

  • 标签: 环境友好 重庆市 企业 西南 环境保护局
  • 简介:分析了影响45Mn17Al3钢磁导率性能的主要因素。通过工业试验确定了合理的化学成分、热处理工艺制度及试样表面加工要求等。试验结果表明,45Mn17Al3钢在800、4000及8000A/m三个磁场强度下,相对磁导率μr≤1.005,满足了某些特殊工程对磁性能的较高要求。

  • 标签: 45Mn17Al3钢 磁导率 化学成分 热处理工艺 表面加工要求
  • 简介:SpectralParameterStudyonTm+inNa5Tm(WO4)4CrystalYaoLianzeng(姚连增)(DepartmentofMaterialsScienceandEnginering,UniversityofScienc...

  • 标签: Rare earths NA 5Tm(WO 4) 4
  • 简介:ThephotoluminescencepropertiesofBiTaO4∶Pr3+andBiTaO4atroomtemperaturewerestudied,andtheinfraredtransmissionanddiffusionreflectionspectraofBiTaO4weremeasured.ThephotoluminescencespectrumofBiTaO4peaksatabout420,440and465nm.Therehasanobviousexcitationbandfrom330to370nm.ThephotoluminescencespectrumofBiTaO4∶Pr3+consistsofthecharacteristicemissionofPr3+,anditsmainpeakisat606nmfrom3P0→3H6transitionofPr3+.Itsexcitationspectrumconsistsofthewidebandwithmaximumat325nm,thewidebandintherangeof375~430nm,andthecharacteristicexcitationofPr3+.Thebandsat325nmand375~430nmmaybefromtheabsorptionofthechargetransfertransitionofthetantalategroupanddefectenergylevelsinitsforbiddenband,respectively.ThereisenergytransferfromhosttoPr3+.BecauseboththehostdensityandphotoluminescencepeakintensityofBiTaO4∶Pr3+aresuperiortoPbWO4,BiTaO4∶Pr3+maybeapotentialheavyscintillator.

  • 标签: BiTaO4 稀土 掺杂 发光材料 发光性能
  • 简介:TheeuropiumionsdopedMMoO_4(M=Sr,Ba)nanophosphorsweresuccessfullysynthesizedviaafacilehydrothermalmethodusingisopropanol.Therelationshipbetweenphosphorcrystallinephase,morphology,photoluminescentpropertiesandhexadecyltrimethylammoniumbromide(CTAB)concentration,pHvalueinprecursorsolutionwasinvestigated.TheresultsindicatedthatthemorphologyandphotoluminescentpropertieswerestronglyinfluencedbyCTABconcentrationandpHvalueinprecursorsolution.InSrMoO_4:Eu~(3+)hosts,thephosphorsurfacetendedtobecomesmootherastheconcentrationofCTABwasincreased;whileparticlestendedtoagglomerateasincreasingpHvalue.TherelativeintensityratioofchargetransferbandtoEu~(3+)characteristicemissionpeaksofMMoO_4:Eu~(3+)(M=Sr,Ba)waschangedasCTABconcentrationandpHvaluechanged.TheemissionspectraofMMoO_4:Eu~(3+)(M=Sr,Ba)couldbeadjustedbyCTABconcentrationandpHvalueduetotheirimpactsonthestructure.ItwasimportantthatthedifferentmorphologiesandphotoluminescentpropertiesofMMoO_4:Eu~(3+)(M=Sr,Ba)couldbeobtainedbythefacilehydrothermalmethodandmodulatedbychangingCTABconcentrationandpHvalue.

  • 标签: 纳米发光材料 铕离子掺杂 水热法 SR 发光特性 合成