简介：通过非自耗磁控电弧炉熔铸和700℃,20h高温退火处理,制备出含铬18%～30%(质量分数)含Laves相TiCr2过共析钛铬合金,并研究其中的组织变化规律.研究结果表明,稳定化系数为2.57～4.62的过共析钛铬合金经过熔炼后,在随炉冷却的条件下得到的是单相β-Ti组织;铸态合金在700℃保温退火时,金属间化合物TiCr2不仅沿晶界生成并形成连续分布,还将在基体内部弥散析出;在随后的空冷过程中合金内局部会发生β-Ti→α-Ti+TiCr2共析分解.合金含铬量越高,在高温退火时析出的TiCr2量越多,粒径越大,合金的硬度也越高.电弧熔炼加上700℃,20h高温退火是一种制备含Laves相过共析钛铬合金的可行工艺.

简介：Loadedonthecordierite,therareearthdopedcompositecatalystwaspreparedbysol-gelmethodcombinedwithdippingtechnique.TakingOrthodichlorobenzeneasmodel,thecatalystwasusedtoremovethedioxinsofthewastegas.Theresultsshowedthatat280℃andgasspacevelocitybeing8000h-1,theorthodichlorobenzenecouldberemovedeffectivilybythepreparedCeO2-TiO2-V2O5compositecatalystwhoseactivitywasremarkablyenhancedbythedopingofCe,whiletheindustrialside-streamtestofdioxinsfromrefuseincinerationsmokeindicatedthatthedecompositionratecouldreachabove93%underthesameconditions.

简介：Inthiswork,boththethermalexpansionandelectricalconductivityofnanocrystallineLa2Mo2O9werestudied.ThenanocrystallinepowderofLa2Mo2O9wasobtainedbysol-gelmethod,andwiththehelpofSHP(superhighpressure)upto4.5×104atmat700℃forashorttime,andthenanocrystallinepowderwasdensifiedwithoutobviousparticlesizegrowth.TheelectricalconductivityofnanocrystallineLa2Mo2O9wasoneorderofmagnitudelowerthanthatofthemicrocrystallinesampleatthesametemperature.Owingtothephasetransition,themicrocrystallineLa2Mo2O9hasanabruptincreaseofthermalexpansionwithapeakvalueof48×10-6K-1at556℃.Forthenanocrystallinematerial,thepeakvalueincreasesto112×10-6K-1at520℃.Ontheotherhand,above600℃thesignificantgrowthofparticlesizeofthenanocrystallineLa2Mo2O9wasobserved,accompanyingbyatremendousincreaseofthermalexpansionwithapeakvalueofthirdhigherthanthatofLa2Mo2O9.

简介：Basedonthethermodynamicallyself-consistentanalysisandoptimizationofthreesub-binarysystemsoftheternarysystemPrCl3-CaCl2-MgCl2,thethermodynamicsofthisternarysystemhasbeenstudied.UsingHillertmodelandtakingMgCl2asanasymmetriccomponent,thePrCl3-CaCl2-MgCl2phasediagramhasbeencalculated.Theagreementbetweencalculatedandmeasuredcompositionsandtemperaturesatdeflectingpointsonliquidusisgood.Thesystemisasimpleeutecticonewithaeutecticpointat26.0mol%PrCl3,41.5mol%CaCl2,32.5mol%MgCl2;560℃（calculated）and26.0mol%PrCl3,39.4mol%CaCl2,34.6mol%MgCl2;546℃（measured）,respectively.

简介：TheZrO2-Al2O3ceramiccompositeswerepreparedbyappropriatetechniqueswithcommercialZrO2andAl2O3powdersasrawmaterialsandY2O3asstabilizer.TheresultsindicatethatwiththeintroductionofAl2O3intotheZrO2matrixwherethequantityofadditiveY2O3is3.5%(molefraction),thegrowthofZrO2grainsisefficientlyinhibited,whichhelpstheZrO2grainsexistinametastabletetragonalmanner;thushigherstrengthandtoughnessareacquired.Whenthecontentofaluminais20%(massfraction),thebendingstrengthandfracturetoughnessofthecompositesare676.7MPaand10MPa·m1/2respectively,themechanicalbehaviorsareclosetothosepreparedwithZrO2andAl2O3powderssynthesizedthroughwetchemicalapproach.Themechanicalbehaviorsofthecompositesarewellimprovedowingtothedispersiontougheningofaluminagrainsandphasetransformationtougheningofzirconiagrains.

简介：Differentrareearth(RE)ionsdopantswereaddedintotheSrAl2SiO7:Eu2+phosphorsinordertoenhancethephosphorescenceproperties,andtheeffectoftheREionsincludingYb3+,Ce3+,Nd3+,Dy3+andTm3+,wascomparativelyinvestigated.ItwasfoundthatNd3+additionimprovedthephosphorescencepropertiesobviouslyamongallthestudiedREions.Therefore,Sr1.96–xAl2SiO7:xEu2+,yNd3+phosphorswerestudiedindetail,andtheoptimumEu2+andNd3+concentrationsweredeterminedwiththeafterglowtimeofabout20min.Thephasestructures,photoluminescence(PL)properties,long-lastingphosphorescence(LLP)properties,afterglowdecaycurvesandthermo-luminescence(TL)fortheselectedphosphorsduringthecorrespondingstudywereinvestigated.AllthephosphorsexhibitedgreenPLemissionandLLPemission.ThereweretwoTLbandslocatedatabout325and380Kforthestudiedsamples,andtherelationshipbetweenREadditionandphosphorescencepropertieswasdiscussed.

简介：FluorescencespectraofSm2+andEu2+→Sm2+energytransferwerestudiedinSrB4O7.Thereappearsonlyfluorescencefrom5D0transitionofSm2+at77K.Thevibroniclinesassociatedwith5D0→7F0transitionwereobserved.Thethermalpopulationtoupperstatesof5D1and4f5dlevelsfrom5D0givesriseto5D1→7FJand5d→4fradiativetransitionsofSin2+athighertemperature.

简介：Reactionof(MeC5H4)3LnwithHOCH2CH2NMe2intetrahydrofuran(THF)givesthenewcomplexes[(MeC5H4)2Ln(μ-OCH2CH2NMe2)]2(Ln=Sm,Y,Nd)withnitrogenfunctionalizedμ-alkoxideligand.ThecomplexeswerecharacterizedbyelementalanalysisandIR,and[(MeC5H4)2Sm(μ-OCH2CH2NMe2)]2wasstructurallycharacterizedbytheX-raydiffractiontobeadimerformedbytwounsymmetricoxygenbridges.ThecomplexhasatricyclicskeletonwiththeadditionaltwoSm-NbondsviaintramolecularcoordinationofOCH2CH2NMe2.ThecoordinationnumberofthecentralmetalSmisnine.Thetitlecomplexesshowgoodcatalyticactivityforring-openingpolymerizationofε-caprolactone.

简介：采用碱熔处理样品，酸化后，移取部分溶液稀释后引入ICP测定ZrO2、TiO2、Fe2O3含量，剩余溶液用强碱分离钛、铁、锰等干扰元素后，EDTA—CuSO4法返滴定Al2O3，终点明显，检测重现性好；

简介：增加的CeO2(ZrO2)/TiO2催化剂独立由大音阶的第五音胶化和受精的方法准备了的一系列镨为选择催化减小被测试没有，并且由X光检查衍射(XRD)描绘了，N2-brumauer-emmett-teller(N2-BET),NH3-temperature规划了解吸附作用(NH3-TPD),H2-temperature规划了减小(H2-TPR),PL系列，拉曼系列，电子顺磁的回声(EPR)一催化性能上的准备方法的影响被学习。结果证明CeO2(ZrO2)/TiO2催化剂的催化性能上的Pr增加的影响在大音阶的第五音胶化方法和受精方法之间是不同的。Pr增加趋于与TiO2交往并且当它是更可能的与在受精方法形成Ce-O-Pr的结构的CeO2交往时，在大音阶的第五音胶化方法形成了Ti-O-Pr的结构。大音阶的第五音胶化方法准备的催化剂的全部的酸数量和氧化还原作用性质与Pr元素的增加减少了，它导致了催化活动的减少。相反，受精方法准备的增加Pr的催化剂被发现拥有更容易的reducibility，更多的全部的酸数量和Ce3+种类的更高的比例，它为更高催化的活动是赞成的。

简介：在甲烷(POM)的部分氧化的催化活动和稳定性混合方法的CeO2-ZrO2和-Al2O3的影响在Ni/Ce0.7Zr0.3O2-Al2O3催化剂上被调查。催化剂被XRD，TPR，H2-chemsorption，和TG-DTA描绘。为新鲜催化剂，结果证明混合催化剂(原子)的盐先锋比混合方法(摩尔)和机械地混合方法(MECH)的粉末的催促的人准备的催化剂介绍了更好的性能。XRD的结果建议在在原子样品的CeO2-ZrO2和Al2O3之间的相互作用比其它强壮，它导致了更多的格子缺点和从而更好的起始的活动。而且，MECH样品在24h稳定性测试有最好的稳定性和最少的焦炭免职。TPR和H2-chemsorption的结果显示在MECH样品的Ni-Al的亲密接触提高了抵抗焦炭免职和金属sintering的能力。

简介：Inthispaper,varioustechniquesincludingBET,XRD,SEMandXPSwereusedtostudythesinteringofpureandLa2O3-dopedtitania.Theexperimentalresultsshowthatsinteringoftitaniaproceedsviavolumediffu-sion.Addingoflanthanumoxidedecreasestherateofsinteringandhindersthephasetransitionfromanatasetorutilecrystalbystrongsurfaceinteractionbetweenthemixedcrystals(La4Ti9O24,La0.66TiO2.99)andTiO2.

简介：Ni-W-P-CeO2-SiO2nano-compositecoatingswerepreparedonthecarbonsteelsurfacebypulseco-depositionofnickel,tungsten,phosphorus,nano-CeO2andnano-SiO2particles.Theinfluenceofnano-SiO2particlesconcentrationsinelectrolyteonmicrostructuresandpropertiesofthenano-compositecoatingswereresearched,andthecharacteristicswereassessedbychemicalcompositions,elementdistribution,depositionrate,microhardnessandmicrostructures.Theresultsindicatethatwhennano-SiO2particlesconcentrationsinelectrolytearecontrolledat20g·L-1,thedepositionratewith27.07μm·h-1andthemicrohardnesswith666Hvofthenano-compositecoatingsarehighest,elementlinescanningandareascanninganalysesshowthattheaveragecontentsofelementsW,P,SiandCeinthenano-compositecoatingsareclose,displayingthatthedistributionofeveryelementwithinthenano-compositecoatingsiseven.Anincreaseinnano-SiO2particlesconcentrationsinelectrolyte(whenlowerthan20g·L-1)leadstorefinementingrainstructureofnano-compositecoatings,butwhenitimprovedto30g·L-1,thecrystallitesizesincreaseagainandinthemeantimetherearealotofsmallbosswithnodulationshapeappearingonthesurfaceofnano-compositecoatings.

简介：Ca8Mg(SiO4)4Cl2:Eu2+phosphordopedwithSr2+cationforCa2+partially,wassynthesizedbysolid-statereactionathightemperatureunderreducingatmosphere,anditsluminescentpropertieswereinvestigated.TheexperimentalresultsindicatethattheemissionintensityofthephosphorincreasesafterbeingdopedwithafewamountofSr2+ion.Theemissionpeakofthephosphorblueshifttoabout464nmwhenthephosphorisdopedwithlargequantityofSr2+ions.TheexcitationspectrumindicatesthatthephosphorcanbewellexcitedbyUVandbluelightfrom300to460nm,andthephosphorwasfittedwellfortheexcitationbyUVorblue-LED.

简介：作为报导Y2O2S的改进:Tb3+，白光的长持续的黄磷：Y2O2S:Tb3+，Sm3+被准备由固态反应。光致发光系列证明在紫外刺激下面的Tb3+和Sm3+排出物的位置和形状在这位主人是类似的，它在不同刺激下面保证了一种稳定的白排放颜色(IEC的日光标准)。共同做的样品的腐烂曲线显示二个离子的排出物的腐烂时间是靠近的。热照明测量建议做的Sm3+离子创造的陷井是有用的推迟共同做的样品的白晚霞。因此，共同做的Sm3+离子的功能作为改进样品的白排放颜色并且充当新陷井中心被证实。

简介：CeZr，CeYZr，LaCeZr，LaCePrZr，LaCePrYZr，和LaCePr稳固的答案经由一起沉淀方法被准备，并且借助于X光检查衍射(XRD)和Brunauer-Emmett-Teller(赌注)技术描绘了。稳固的答案的氧存储能力(振荡)被脉搏技术评估，催化活动用一台4隧道催化作用设备被估计。稳固的答案介绍了立方的结构，这被看见。特定的表面区域和热稳定性能被做Y进稳固的答案提高。当做大量La减少了时，做La的小数量在热耐久性上有积极效果特定的表面区域和热稳定性。LaCePrZr和LaCePrYZr固体解决方案用在Nd抽取在特定的表面区域和热稳定性介绍了某个更高的值以后，与LaCePr充实的Baotou稀土元素矿物质残余综合了，当为汽车的经济催化剂用尽纯化，从而启用被过去常。ceria氧化锆固体答案的表面上的涂层Al2O3或SiO2层增加了特定的表面区域和热抵抗。

简介：Ca-dopedBaMgAl10O17:Eu2+,Mn2+(BAM)bluephosphorsweresynthesizedbyfluxassistedsolid-statereactionmethodusingCaF2andBaF2asco-flux.GooddispersityandparticlesizehomogenizationofhexagonalpurephaseBAMwereobtainedbysinteringat1400℃.TheeffectsoftheCa2+ionscontentonthestructure,morphologyandphotoluminescencepropertiesofthephosphorswerestudied.TheresultsindicatedthattheincorporationofCacoulddecreasethelatticeconstant,improvethehomogeneityanddispersityandenhancethephotoluminescence(PL)intensityofthephosphoreffectively.TheoptimumBa0.86Ca0.04Mg0.97Al10O17:0.1Eu2+,0.03Mn2+PLintensitywasenhancedforabout30%andrelativebrightnesswasimprovedabout4%.Furthermore,thesynthesizedBAMandcommercialBAMphosphorswereannealedfor30minat600oCinair.TheCa-dopedphosphorshadstrongeremissionintensity,higherbrightnessandbetterchromaticitystabilitythanthatofthecommercialphosphor.TheseresultsindicatedthatCa-dopedbluephosphorshadgoodpotentialapplicationsinthecommercialtricolorfluorescentlampsaswellasinotherdisplayandlamps.

简介：AseriesofCe0.5Fe0.30Zr0.20O2catalystswerepreparedbydifferentmethods(co-precipitationsmethod,citricacidsol-gelmethod,impregnationmethod,physicalmixedmethod,andhydrothermalmethod)andcharacterizedbyX-raydiffraction(XRD),Ramanspectroscopy,Brunauer-Emmett-Teller(BET)andH2-TPRmeasurements.Potentialofthecatalystsinthesootoxidationwasevaluatedinatemperature-programmedoxidation(TPO)apparatus.TheresultsshowedthatalltheFe3+andZr4+wereincorporatedintocerialatticetoformapureCe-Fe-Zr-Osolidsolutionfortheco-precipitationsample,buttwokindsofFephasesexistedintheCe-Fe-Zr-Ocatalystspreparedbyothermethods:Fe3+incorporatedintoCeO2latticeanddispersedFe2O3clusters.ThefreeFe2O3clusterscouldimprovetheactivityofcatalystsforsootoxidationcomparingwiththepureCe-Fe-Zr-OsolidsolutionowingtothesynergeticeffectbetweenfreeFe2O3andsurfaceoxygenvacancies.Inaddition,theactivityofcatalystsstronglyreliedonthesurfacereducibilityoffreeFe2O3particles.HoldingbothabundantfreeFe2O3particlesandhighoxygenvacancyconcentration,thehydrothermalCe0.5Fe0.3Zr0.2O2catalystpresentedthelowestTi(251°C,ignitiontemperatureofsootoxidation)andTm(310°C,maximumoxidationratetemperature)forsootcombustion(withtight-contactbetweensootandcatalysts)amongthefivesamples.Evenafteragingat800°Cfor10h,theTiandTmwerestillrelativelylow,at273and361°C,respectively,indicatinghighcatalyticstability.

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