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简介：1.IntroductionLightrareearthadditioncanremarkablyenhancetheservicelifeofFe-Cr-Alalloyforelectricalheatingelement,butitscontentinthealloymustbecontrolledbelowthelevelof0.1wt-%.Whenthecontentexceedsthat,theperformance

简介：用基于密度泛函理论的全势线性缀加平面波方法和模拟缺陷结构的超原胞的方法，通过计算比较ZnO、Zn15Y1O16Zn16O15、Zn15O16和Zn14Y1O16五个体系的自旋极化电子态密度，分析了O空位和Zn空位两种点缺陷对Y掺杂ZnO薄膜磁性的贡献，计算结果表明，氧化锌和钇掺杂氧化锌薄膜的磁性都来源于Zn空位周围被极化的O原子。

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简介：用月桂酸对纳米3Y—TZP粉体进行表面改性，实验结果表明，改性最佳工艺为：月硅酸用量10％、改性时间75min、改性温度60％。经表面改性的粉体，由引起团聚的强极性多羟基表面结构变为非极性有机表层结构，粉体间作用力减小，硬团聚消失，大幅度提高了陶瓷体的烧结性能。

简介：WehavestudiedtheMossbauereffectofYBa2Cu2.88Fe0.12O7-xsuperconductiveoxidefrom78to273K.TwominimaofrecoillessfractionandDebyetemperaturewerefoundnear110Kand220K.Itmeansthatlatticesofteninghappenednearthesetwotemperatures.Wealsoobservedminimaofisomershiftnear110Kandquadrupolesplittingincreasewhentemperatureislowerthan110K.Wesuggestthatlatticesofteningwouldleadtothedisplacementofoxygenatoms.Thismayberelativetosuperconductivetransition.

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简介：以超重力场辅助燃烧合成技术制备了呈梯度分布的Y2O3-Al2O3-SiO2玻璃／Y3Al5O12陶瓷梯度复合材料。结果表明，梯度布置两种组分的原料既可防止下层熔体的喷溅，又能提高上层玻璃的透过率。该梯度材料沿超重力方向依次为YAS透明玻璃层、YAS-YAG玻璃陶瓷层和YAG陶瓷层。

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简介：相等的隧道(ECAP)处理的尖紧迫和常规挤出(前)被用于Mg-12Gd-3Y-0.5Zr(wt%)镁合金以便在机械性质评估潜在的改进。ECAP实验在380污瀠潲散被进行吗？

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简介：TheRamanspectraof3%(molefraction)Y2O3-ZrO2(3Y)areobtainedatdifferenttemperaturefrom77Kto853K.Theresultsshowthat260cm-1Egand460cm-1Egmodesonthespectrashifttowardlowerwavenumberwiththeincreaseoftemperature;meanwhile,thecontinuityoftheHalfWidthatHalfMaximum(HWHM)andwavenumber(frequency)ofRamanbandsarebrokenandt-phaseonlypartiallytransformstom-phaseat523K.Basedontheexperimentalresults,thispaperdiscussesthet-phaselatticevibrationof3YandpresentstheimagesofvibrationdisplacementofsixRaman-activemodesfort-phaseofZrO2.TheanalysisindicatesthattherearediversitiesexistinginthedisplacementoftheatomicvibrationofRaman-activemodesbecauseoftheirdifferentsymmetriesatvarioustemperature,whichleadstothedifferentchangetendenciesofRamanbands.Furthermore,theabruptchangesofsomeRaman-activemodesindicatingtheatomicdisplacementareassumedtobethecondensationsofphononmodesinthet→mphasetransition.

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简介：biomagnesium合金被认为由于它的好机械相容性，生物相容性，生物安全和可被细菌破坏的特征是最潜在的可被细菌破坏的金属材料之一。然而，在生理的环境和低机械性质的高降级率的二个主要问题阻止biomagnesium合金的发展。在现在的工作，Mg-Zn-Y-Nd合金的样品被周期的挤出压缩(CEC)和相等的隧道准备尖紧迫(ECAP)。微观结构，合金的机械性质和它在模仿的身体液体(SBF)的腐蚀行为被评估。结果表明那Mg-Zn-Y-Nd合金与测微计尺寸和缩放nano的秒阶段的同类的分发由equiaxial罚款谷物结构组成，它被动态再结晶在ECAP和CEC期间引起。合金的腐蚀抵抗被改进。张力并且腐蚀抵抗被改进，特别处理合金展览制服腐蚀表演和减少的腐蚀评价。这将作为脉管的stent申请为Mg-Zn-Y-Nd合金提供理论地面。

简介：Thisstudywasconductedtodiscusstheeffectofrollingstrainonmicrostructureandtensilepropertiesofdual-phaseMg-8Li-3Al-2Zn-0.5Y(wt%)alloy,whichwaspreparedbycasting,andthenhomogenizedandrolledat200℃.Therollingprocesswasconductedwith10%reductionperpassandfivedifferentaccumulatedstrains,varyingfrom10%to70%.Theresultsindicatethattheas-castandas-rolledMg-8Li-3Al-2Zn-0.5Yalloysarecomposedofα-Mg,β-Li,AlLiandAl2Yphases.Afterrollingprocess,anisotropicmicrostructurewasobserved.a-Mgphasegotelongatedinbothrollingdirectionandtransversedirectionwiththeadditionofrollingstrain.Consequently,thestrengthofthealloyinbothdirectionswasnotablyimprovedwhereastheelongationdeclined,mainlycausedbystrainhardeninganddispersionstrengthening.Thetensilepropertiesoftheas-rolledalloysintheRD,nomattertheYS,UTSortheelongation,arehigherthanthoseoftheTDduetotheirlargerdeformationstrainandsignificantanisotropyinthehcpα-Mgphase.Inaddition,thefractureandstrengtheningmechanismofthetestedalloyswerealsoinvestigatedsystematically.

简介：利用稀土Ln=Y／Yb对SmzZr2O7进行A位取代掺杂，通过固相合成法制得Sm1.8Ln0.2Zr2O7（Ln=Y／Yb）陶瓷材料。分别利用XRD分析材料的晶体结构，SEM观察其显微形貌，激光导热仪测试其热扩散系数并计算得到热导率。结果表明，Sm1.8Ln0.2Zr2O7（Ln=Y／Yb）陶瓷材料为立方烧绿石结构，晶粒分布均匀，Yb3＋／Y3＋的掺杂降低了陶瓷材料的热扩散系数和热导率，其中Yb的作用更为明显。

简介：Withpositronannihilationradiationonedimensionangular-correlationdevice,itismeasuredthatpositronannihilationradiationonedimensionangular-correlationcurvesofpolycrystalsodiumionconductorNa5Y1-xCrxSi4O12（NYCS）system.Afterelectronmomentumdistributioncurvesarenormalized,linearparametersarecalculated.TheparametersH,WandSshowthechangeofNa+ionvacancyconcentrationinNYCSseriessamples.TheresultsshowthatparametersH,WandSofonedimensionangular-correlationcurvesofthosesamplesvarygreatlywithCr2O3contents.WithCr2O3contentincreasing,HandSparametersincrease,butWdecreases,andreachesextremesatx=0.05;thenwithCr203addingcontinually,parametersHandSdecreasegradually,parameterWincreasesgradually.Thisshowsthat,inaddtiontoCr2O3,theconductivityhascloserelation