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367 个结果
  • 简介:Athree-dimensionalmathematicalmodelofthecombustionofpulverizedcoalandcokehasbeendeveloped.Themodelisappliedtotheblowpipe-tuyere-raceway-cokebedregioninanironmakingblastfurnaceinonecomputationaldomain,whichincludestwoparts:pulverizedcoalcombustionmodelintheblowpipe-tuyere-racewaycavityandthecoal/cokecombustionmodelinthesurroundingcokebed.Theeffectsofcoalpropertiesareexaminedcomprehensively,intermsofcoalburnoutandgasspeciesdistributions.TheresultsindicatethatusingacoaloffineparticlesizeorhighVMcontentcouldimproveburnoutandwouldaffectthegascompositionconsiderably.Theburnoutisexaminedintwoways:comparedwithburnoutalongtuyereaxis,burnoutovertheracewaysurfaceisamoresensitiveandsensibleparametertodescribetheamountofunburntcharenteringthecokebed.Themodelisusefulforexaminingtheflow-thermo-chemicalcharacteristicsofthepulverizedcoalinjection(PCI)processundervariousconditionsinablastfurnace.

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  • 简介:Aconoscopicholography-based3Dmeasurementsystemforanalyzingthedefectsonthesurfaceofsteelplateswasintroducedinthispaper.Thehardware,whichisautomatedthroughsoftware,performssamplingofthesteelplatesurface.Throughthesoftwareinterface,point-clouddataofthesteelplatesurfaceareobtainedandreconstructedtoforma3Dimageofthesteelplatesurface.Thesoftwareallowsautomaticanalysisofsteelplatesurfacedefectsthroughidentificationofthebulgesanddepressions.Inaddition,thesoftwarecanalsoautomaticallycalculatethedefectinformation,suchasthedeepestpoint,volume,openingarea,openinglength,andsoon,therebydeterminingthedefectsize.Theresultsdeterminedbythis3Dmeasurementsystemwerefoundtobeingoodagreementwiththeactualvalues.

  • 标签: 三维测量系统 表面缺陷 钢板 全息技术 光偏振 3D
  • 简介:四lanthanide协作建筑群,也就是[行(2,3-DClBA)3(5,5-dmebipy)(H2O)]2(Ln=Sm(1),Eu(2),Dy(3),惊讶(4));2,3-DClBA=2,3-dichlorobenzoate;5,5-dmebipy=5,5-dmethylbipyridine)被元素的分析,红外线的光谱学和单个水晶X光检查衍射综合并且描绘。调查结果显示建筑群3是一个dinuclear分子,并且中心Dy3+是八坐标的。每个dinuclear单位能被H债券和卤素卤素相互作用连接。建筑群2的光性质建议了Eu3+离子的典型强烈排出物。热分析证明建筑群在三分解了步:协作水然后第一被失去中立ligand5,5dmebipy被失去,最后,2,3-DClBAligand被失去。

  • 标签: lanthanide 建筑群 水晶结构 超分子 H 债券 卤素卤素相互作用 光性质
  • 简介:ThephaseandmorphologytransformationduringthehydrothermaltreatingprocessofY2O3wasevaluatedwithX-raydiffcrcnce(XRD),scanningelectronmicroscopy(SEM),transmissionelectronmicroscopy(TEM),particlesizeandspecificsurfaceareadetermination.TheresultsshowedthatthecubicY2O3didnottransferintohexagonalY(OH)3inpurewater.Therefore,purehexagonalY(OH)3withnanotubeandmicrorodmorphologieswereobtainedbyhydrothermaltreatingY2O3at150℃for12hin15mlof2mol/LNaOHsolutionwithandwith-outPVAorPEGItwassuggestedthatthecharacteristicpreferentialgrowthofY(OH)3wasattributedtothestructureanisotropyofhexahedronY(OH)3.TheadditionofPVAorPEGcouldpromotetheformingprocessofnanotubesbyselectiveadsorptionondifferentcrystalplanes,whichalteredthegrowthratealongdifferentdirectionsandresultedinthediffusionlimitofconstructingionsinthecentertopofrods.Finally,Y(OH)3:EuandY2O3:Eunanotubeswerealsosynthesizedbyusingthismethod,andtheirphotoluminescencepropertieswereevaluated.

  • 标签: HYDROTHERMAL synthesis Y(OH)3 Y(OH)3:Eu Y2O3:Eu NANOTUBE
  • 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:云南驰宏锌锗股份有限公司会泽铅锌矿是我国一个千米深井矿山,其下属8号矿体采深已达1200余米,矿体赋存条件复杂,地应力高,导致微地震活动频发。本文根据微震监测数据及井下开采活动,对微震活动的时空分布、诱发模式以及预测预报进行了研究。结果表明:微震活动的时空分布主要与开采活动及地质构造有关,根据发生位置、震级大小、破坏特征可将微地震的诱发模式分为应变破裂、矿柱冲击以及断层滑移破裂三类,阐述了各自的发生机制。提出以地震学参数一活动率∑N/Δt、视体积VA、能量指数EI的时间序列曲线来预测矿震灾害,并对其物理意义及破坏过程中可能出现的特征进行了理论分析,现场应用后证明:地压灾害发生前,活动率∑N/Δt及视体积VA急剧增加,能量指数EI突然降低。

  • 标签: 深井开采 微震活动 时空分布 预测预报
  • 简介:YbAl3(BO3)4crystalofgoodopticalqualitywasgrownbythefluxmethod.ThestructureofYbAl3(BO3)4crystalwasdeterminedbysingle-crystalX-raydiffraction.TheexperimentshowsthatYbAl3(BO3)4belongstothedoubleborateswithatrigonalstructure.ThespacegroupisR32anditsunitcellconstantsweremeasuredtobea=0.92965nm,c=0.72129nm,V=0.53673nm3,Z=3.Thetransmittancespectraweremeasured.Thecut-offofYbAl3(BO3)4crystalis216nm,andtherearetwoabsorptionpeakslocatedat940and975nmfrom190nmto2600nm.ThethermalpropertiesofYbAl3(BO3)4crystalwerestudiedforthefirsttime.Theaveragethermalexpansioncoefficientsweredeterminedtobe2×10-6/℃,9.5×10-6/℃alonga-andc-direction.ThespecificheatofYbAl3(BO3)4crystalwasmeasuredtobe0.6695J·(g·℃)-1atroomtemperature.AllresultsindicatethattheYbAl3(BO3)4crystalisanexcellentstoichioimetriclasermaterial.

  • 标签: YbAl3(BO3)4 CRYSTAL TRANSMITTANCE SPECTRA thermal properties
  • 简介:在达到一定勘查程度的金矿区,有条件的合理利用部分D级储量作为矿山建设依据,可以减少投资风险,保障黄金生产稳步发展。

  • 标签: 黄金 D级储量 利用
  • 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:本文采用高温团相反应合成TCaTiO3∶Pr3+红色发光材料、报道了Pr3+激活的CaTiO3的光谱特征及长余辉特性,并与CaS∶Eu的光谱特性及长余辉进行了比较。CaTiO3∶Pr3+将是一种具有广泛用途的新材料

  • 标签: CaTiO3∶Pr3+ 合成 发光特性 长余辉
  • 简介:介绍了武山铜矿中段运输系统原3m3底侧卸矿车的设计特点。结合生产实际状况,对3m3底侧卸矿车在运行过程中出现的问题进行了分析,总结产生故障的原因,针对性的提出改进措施。现场使用表明,通过改进后,取得了良好效果,满足了矿山生产的需要。

  • 标签: 底侧卸矿车 轮轴 卸载轮 车箱 改进措施
  • 简介:Eu3+activatedSr1–xEuxZrO3(x=0.01–0.04)phosphorwithperovskitestructurewassuccessfullysynthesizedbyusingcombustionmethod.Thestructure,morphologyandopticalpropertiesofthematerialwerecharacterizedbyX-raydiffraction,scanningelectronmicroscopyandfluorescencespectrometry.TheXRDresultsindicatedthatcrystalsofSrZrO3:Eu3+belongstotetragonalperovskitesystem.ThephosphorcouldbeeffectivelyexcitedbyUVlightandtheemissionspectraresultsindicatedthatreddish-orangeluminescenceofSrZrO3:Eu3+duetomagneticdipoletransition5D0→7F1at593nmwasdominant.Thus,thepreparedphosphorshowedremarkableluminescentpropertieswhichfindapplicationsinfieldemissiondisplay(FED)andplasmadisplaypanel(PDP)devices.

  • 标签: 钙钛矿结构 铕激活 荧光粉 光学特性 合成 扫描电子显微镜
  • 简介:以奥氏体再结晶型控制轧制和未再结晶型控制轧制相结合的轧制工艺生产的Q345D钢板,其组织均匀、晶粒细小、性能良好,特别是低温韧性较好,达到了控制轧制的目的。

  • 标签: Q345D 宽厚板 控制轧制
  • 简介:Calciumtitanatedopedwithpraseodymiumwaspreparedthroughsolidstatereactionanditexhibitedintenseredemissionat612nm.Phosphorswerecharacterizedforphotoluminescence,thermo-luminescenceandafterglowemissions.Studyofeffectsofrareearthsonphotoluminescenceaswellasafterglowintensitywasreported.Presenceofgadoliniumenhancedluminescence.Presenceofsomemonovalentionsenhancedbothafterglowandphotoluminescenceemission.Thermo-luminescenceglowcurveswereanalyzedand...

  • 标签: perovskites 钙 titanates 红晚霞 稀土元素
  • 简介:在石灰窑大修过程中对石灰窑存在的薄弱环节采取了一些改进措施,建造新型石灰窑可以从根本上扭转公司石灰生产的被动局面。

  • 标签: 石灰窑 大修 窑体 耐火材料
  • 简介:Er~(3+)andLa~(3+)codopedY_2O_3nanocrystallinepowdersweresynthesizedbygelcombustionmethodandcharacterizedwiththermalanalysis,X-raydiffraction(XRD),transmissionelectronmicroscopy(TEM),high-resolutionTEM(HRTEM)techniquesandfluorescencespectroscopy.Afterbeingcalcinedat1200oC,the(Y_(1–x)La_x)_2O_3:Er~(3+)powderswereconfirmedtobecubicY_2O_3phasewiththecrystallinegrainsizeintherangeof20–40nm.TheEr~(3+)emissionat1.53μmfromthe~4I_(13/2)→~4I_(15/2)transitionwasobserved,whichwasfoundtobeenhancedbyintroducingLa~(3+)ions.SuchenhancementcouldbeattributedtotheadjustmentofEr~(3+)ions'localenvironmentbythecodopingofLa~(3+)ions,leadingtotheincreasedgroundstateabsorptioncrosssectionofEr~(3+)ions.

  • 标签: POWDERS IONS crystalline CALCINED attributed cubic
  • 简介:Duetotheremarkablemagnetoresistance(MR)effectonperovskite-typemanganite,magnetoelectronicsandspintronicshavebecomeattractivesubjectsofexperimentalandtheoreticalinvestigationsfortheapplicationpurpose.(La0.9Nd0.1)2/3Ca1/3Mn1-xFexO3(x=0,x=0.05)werepreparedsuccessfullybysol-gelmethod.Thestructure,magneticproperties,andtransportpropertiesofthecompoundswereinvestigated.Themagnetoresistanceeffectdependsonthecompositionandthetemperature.XRDpatternsshowthatthecompoundisasinglephasepolycrystalwithpseudocubicstructure.Alargenegativeisotropicmagnetoresistanceeffectinthesampleswereobservedatlowtemperatureregion.ThemaximumMRofthesampleswas77%and97%,respectively.Itwasmostlikelyduetothescatteringorthetunnelingtransportofspin-polarizedcarriersinlatticeunderstrongmagneticfield.

  • 标签: SOL-GEL method MAGNETORESISTANCE effect PEROVSKITE pseudocubic
  • 简介:InordertosensitizetheluminescenceofEu3+ionsinheavymetalglass,zincleadborateglasssamplescontainingvariousconcentrationsofEu3+andTb3+ionswerepreparedtostudytheTb3+toEu3+non-radiativeenergytransferphenomena.EnergylevelstructuresofTb3+andEu3+ionswereplottedtoshowtheexcitationandenergytransferroutes.EfficientenergytransferfromTb3+toEu3+wasobservedandstudiedqualitativelyintermsofdopingconcentrations.Thesensitizationturnedouttobelesseffectivethanexpected.FurtherstudiestocharacterizetheoxidationofTb3+intotetravalentstateandtoexaminethemechanismofenergytransferareproposed.

  • 标签: energy transfer ZINC LEAD BORATE glass