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130 个结果
  • 简介:Theeffectofanexternalelectricfieldonthecrystallizationbehaviorofamorphous(Nd0.1Fe0.9)3Balloywasinvestigated.ThecrystallizationproductofNd2Fe23B3phasewasobtainedforthisamorphousalloyannealedat923Kfor300sinthepresenceofanexternalelectricfieldof300kV·m-1(50Hz);whilethecrystallizationproductsareNd1.1Fe4B4,α-Fe,andFe3Bphasesunderthesameannealingconditionexceptforfree-electricfield.Ontheotherhand,thesampleswereannealedat1023K,whichishigherthanthedecompositiontemperatureofmetastableNd2Fe23B3phase,for600s.Inthecaseofthepresenceofanexternalelectricfield,themetastableNd2Fe23B3phase,asamainphase,isstillstayedinthesample.ThisfactsuggeststhattheexternalelectricfieldenhancesthestabilizationofthemetastableNd2Fe23B3phase.Theeffectoftheexternalelectricfieldonthephaseselectionandstabilizationwasexplainedintermsofthespecificconductancedifferencebetweenthecrystallizationproducts.

  • 标签: 电场 稀土元素 磁性材料 相位选择 无组织合金
  • 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: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: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: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:Magnetizationanddemagnetizationcurvesandhysteresisloopsapplieddifferentmagnetizing.fieldsinsinteredNd-Fe-BandNd-Dy-Fe-Bmagnetsfromthermallydemagnetizedanddcfield-demagnetizedstateswereinvestigatedattemperaturesofupto150℃.Thefirst-quadrantremagnetizationcurvesandthecurvesofcoerciveforces_MH_CversusrernagnetizingfietdsH_mfromdcfield-demagnetizedstateatroomtemperatureshowasteparoundmagnetizingfieldasabsolutevalueofthemaximumintrinsiccoercivity.Thestepsof_MH_C-H_mcurvesshiftedtolowerremagnetizingfieldsandtheshapesofmagnetizationcurveschangedfromsteptypetoprecipitoustypewhentemperaturewentupto100~150℃orafterthespecimenwasthermallydemagnetizedatatemperaturehigherthantheCurietemperature.Thesteepriseofkneecoereivitywithincreasingmagnetizingfieldisbehindthatof_MH_C.NotethatthemagnetichardeninginsinteredNd-Fe-Bmagnetsiscontrolledbypinningofdomainwalls.

  • 标签: MAGNETIZATION COERCIVITY thermally HYSTERESIS ABSOLUTE walls
  • 简介:针对原燃料条件恶化,制定出各项合理的操作制度,使3#高炉各项技术指标大为改善,特别是节焦效果明显。

  • 标签: 3#高炉 操作制度 节焦
  • 简介:Redphosphor(Y,Gd)BO3:Eu3+withgrainshape,smallsize,non-agglomerate,highcrystallinityandgoodphotoluminescence(PL)intensitywaspreparedbyacomplexmethodthattheprecursorofthephosphorwaspreparedbyco-precipitationmethodandthephosphorwaspreparedbycombustionmethod.TheSEMphotosandthephotoluminescencespectrumexcitedunderVUVshowthatthemorphologyandluminescentpropertiesofthisphosphoraresatisfiedwhenanappropriateamountofureawasadoptedasthecombustionagentinthepreparationprocedure.

  • 标签: PDP RED PHOSPHOR CO-PRECIPITATION METHOD combustion
  • 简介:TheelectrodeprocessofY3+iononmolybdenumandnickelelectrodeshasbeenstudiedbycyclicvoltammetryandchronopotentiometryintheYCl3-NaCl-KClmelt.Theoverallchargetransferprocessisatwo-stepreaction:Y3++e=Y2+;Y2++2e=Y.YttriumreducedonthenickelelectrodecanformaseriesofNi-Yalloys.X-raydiffractionanalysiswasemployedtodeterminethealloycompositionsformedunderdifferentcon-ditions.

  • 标签: Y3+ion Mo ELECTRODE Ni ELECTRODE ELECTRODE
  • 简介:3#高炉实行强化冶炼,各项技术经济指标都有长足的进步,但强化必须有精料作前提,各项新技术的应用相辅相成。不断完善操作制度。

  • 标签: 高炉 强化冶炼 精料 顺行
  • 简介:ThephotocatalystsK4Nb6017andK4Nb6017dopedwithFe^3+andCr^3+werepreparedbysolidstatereactionandwerecharacterizedbypowderx-raydiffraction,UV-visdiffusivereflectanceandscanningelectronmicroscopy.ThephotocatalyticactivityofK4Nb6O17andK4Nb6O17dopedwithFe^3+,Cr^3+wereinvestigatedwithmethanolaselectrondonorandPtaspromotercatalystunder+400nmUVirradiation.Thedifferenceofphotocatalyticactivitybetweenthemwasalsodiscussed.TheindividualrateofhydrogenevolutionfortheK4Nb6O17,Fe-K4Nb6O17andCr-K4Nb6O17asphotocatalystsare5.35,5.00,6.25mmol·L^-1.h^-1respectively.

  • 标签: 光接触反应活性 K4Nb6O17 铁离子 CR^3+ 冶炼方法 稀土元素
  • 简介:TheZrO2-Al2O3ceramiccompositeswerepreparedbyappropriatetechniqueswithcommercialZrO2andAl2O3powdersasrawmaterialsandY2O3asstabilizer.TheresultsindicatethatwiththeintroductionofAl2O3intotheZrO2matrixwherethequantityofadditiveY2O3is3.5%(molefraction),thegrowthofZrO2grainsisefficientlyinhibited,whichhelpstheZrO2grainsexistinametastabletetragonalmanner;thushigherstrengthandtoughnessareacquired.Whenthecontentofaluminais20%(massfraction),thebendingstrengthandfracturetoughnessofthecompositesare676.7MPaand10MPa·m1/2respectively,themechanicalbehaviorsareclosetothosepreparedwithZrO2andAl2O3powderssynthesizedthroughwetchemicalapproach.Themechanicalbehaviorsofthecompositesarewellimprovedowingtothedispersiontougheningofaluminagrainsandphasetransformationtougheningofzirconiagrains.

  • 标签: 无机非金属材料 陶瓷 稳定设备 稀土
  • 简介:Ternarycomplexesofeuropiumandterbiumwithbenzoicacidand1,10-phenanthroline[RE(BA)3phen](BA=benzoatephen=1,10-phenanthroline)wereintroducedintoasilicamatrixbysol-gelmethod.Thethermalstabilityandluminescencebehaviorofthecomplexesinsilicagelswerestudiedincomparisonwiththecorrespondingsolid-statecomplexesbythermaldecomposition,excitationandemissionspectra.Thethermalstabilityofthecomplexesisenhancedinsilicagelmatrixandtheluminescenceremainesunchanged.

  • 标签: 溶胶-凝胶 热稳定性 发光性能 二氧化硅 掺杂 稀土