简介:多晶的La1?xKxCoO3(0x0.2)稀土元素cobaltates被一个答案燃烧方法作为燃料用glycine综合了。综合陶器的材料被粉末X光检查衍射(XRD)描绘,扫描电子显微镜学(SEM),Fourier变换红外线的光谱学(FTIR),和磁性的大小并且为物理性质学习了,例如photocatalytic活动。与XRD一起的FTIR大小证明在做的10%K以外的阶段被杂质的小数量伴随。化学滴定为系统的Co3+-Co4+混合原子价显示出Co4+和报道的存在。父母LaCoO3在低温度显示出纺纱眼镜转变,而做的样品从纺纱眼镜行为显示出转变到在K的进步的做上的顺磁的订。这些陶艺的混合售票员自然作为稳固的氧化物的可行候选人放他们燃料房间(SOFC)应用。
简介:研究保温时间对0.98(K0.5Na0.5)NbO3-0.02LaFeO3(缩写为0.98KNN-0.02LF)无铅陶瓷相结构、显微组织、介电性能及铁电性能的影响。所有烧结样品均为纯的伪立方钙钛矿相,保温时间对相结构影响不大。随着保温时间的延长,样品的XRD衍射峰逐渐增强,并且向低角度移动。SEM观察结果显示,随着保温时间的延长,陶瓷样品的致密性提高,晶粒异常长大并出现孪晶结构。介电温谱表明,随着保温时间的延长,介电性能有所降低。电滞回线结果表明,2Pr随着保温时间的延长而增大的程度有所减小,而2E略有增加。在1150℃烧结2h得的到陶瓷的性能较优:εr=2253,tanδ〈5%,2Pr=34.51μC/cm2,2Ec=5.07kV/mm。
简介:ElectrocrystallizationMechanismofTungsteninMoltenKF-B_2O_3-K_2WO_4WenZhenhuanandLiGuoxun文振环,李国勋(GeneralResearchInstiiuteforNo...
简介:TheXRPD(X-raypowderdiffractometry)patternsofsiliconpowderwithaunitcellstructureofdiamondweredeterminedfrom298to1473K.LatticeparametersofSilinearlyincreasewithtemperature.Thethermalshiftsofthepositionsofallreflectionpeaksarelinearlycorrelatedwiththetemperature.Thecoefficientsoftheintrinsiclinearthermalexpansionandvolumetricthermalexpansionweredeterminedas3.87×10-6/Kand1.16×10-5/Krespectively.ItindicatesthatSiisstillasuitablestandardintheXRPDmethodathightemperatures.
简介:1IntroductionTherareearthcobaltalloyshavethepotentialformakingthemagneticandmagnetoopticalmaterials.Sofar,therareearthcobaltalloyfilmsaresubstantiallyproducedbysputteringorvacuumplating.Ifsuchfilmsarepreparedbyelectrodepositioninstead,productionefficiencywouldbeimprovedandthecompositionofthealloycouldbecontrolled.Becausetheoxidationreductionpotentialsofrareearthelementsareverynegative,organicsolventsmaybeusedaselectrolyticmedia.ElectrodepositionofGdCoandSmCoinorganicsolutionshasbeenreporte...
简介:LayeredcathodematerialLiCo1/3Ni1/3Mn1/3O2wassynthesizedbyPechiniprocess,andinvestigatedusingX-raydiffraction(XRD),scanningelectronmicroscopy(SEM)andgalvanostaticcharge/dischargecycling.Thesampleiswell-crystallizedandhasaphase-purea-NaFeO2structure.Theparticlesizesareuniform,anddistributedintherangeof20-200nm.TheinitialdischargecapacityoftheLi/LiCo1/3Ni1/3Mn1/3O2cellwasabout149mAh·g-1whenitwascycledatavoltagerangeof4.5-2.3Vwithaspecificcurrentof0.25mA.Theresultisbetterincomparisonwithsolid-statesolutionmethod.Thesyntheticprocedurewasdiscussed.Threemajorreactions:chelation,esterification,andpolymerizationsuccessivelyoccurred.
简介:LaCrO_3的nano粉末被一条大音阶的第五音胶化线路准备。从350~550K的LaCrO_3nano粉末的热能力被DSC方法测量并且是表示了:C_(p(LaCrO3))(±0.112)=166.844-8.500x10~(-3)T-1.022x10~6T~(-2)(J/(摩尔·K))(350-550K)。一个EMF测量集会为流电的房间作为电解质与CaF_2被开发。可逆房间的FrommeasuredEMF数据,(-)磅,La_2O_3,LaF_3,|CaF_2|O_2(1atm),LaF_3,LaCrO_3,Cr_2O_3,磅(+),和吉布斯的相关价值释放的O_2(1atm)精力,吉布斯LaCrO_3的形成的免费精力从700~885K被计算:ΔG_(f,LaCrO3)~Θ=-1555.364+0.354T(kJ/mol)(700-885K)。并且免费精力从简单氧化物La_2O_3andCr_2O_3反应改变的吉布斯是打算的是:ΔG_(f,公牛(LaCrO3))~Θ=-94.758+8.530x10~(-2)T(kJ/mol)(700-885K)。
简介:介绍了一种自行发明的新的雾化方法。该方法是采用含有固体介质的高速气流即气固两相流对液体金属或合金进行雾化而制备粉末的一种方法,对比研究了同等条件下普通气体雾化与两相流雾化制备粉末的特征,研究了固体雾化过程中主要工艺参数对固体雾化粉末特征的影响规律。结果表明,两相流雾化制得粉末的平均粒度约为普通气体雾化所得粉末的二分之一,而且粒度分布更集中,粉末的冷却速度比普通气体雾化高一个数量级,粉末微观组织更细小;采用液体雾化破碎准则韦伯数以衡量雾化介质的破碎能力,得出两相流雾化介质的韦伯数为气体韦伯数和颗粒流韦伯数之和,建立了两相流雾化破碎的临界方程,并以此讨论了主要工艺规律。
简介:EmployingLi2CO3,NiO,Co3O4,andMnCO3powdersasstartingmaterials,Li[Ni1/3Co1/3Mn1/3]O2wassynthesizedbysolid-statereactionmethod.Variousgrindingaidswereappliedduringmillinginordertooptimizethesynthesisprocess.Aftersuccessiveheattreatmentsat650and950℃,thepreparedpowderswerecharacterizedbyX-raydiffraction(XRD)analysis,scanningelectronmicroscopy,andtransmissionelectronmicroscopy.Thepowderspreparedbyaddingsalt(NaCl)asgrindingaidexhibitaclearR3mlayerstructure.ThepowdersbyothergrindingaidslikeheptaneshowsomeimpuritypeaksintheXRDpattern.Theformerpowdersshowauniformparticlesizedistributionoflessthan1μmaveragesizewhilethelattershowsawidedistributionrangingfrom1to10μm.EnergydispersiveX-ray(EDX)analysissshowthattheratioofNi,Co,andMncontentinthepowderisapproximately1/3,1/3,and1/3,respecively.TheEDXdataindicatenoincorporationofsodiumorchlorineintothepowders.Charge-dischargetestsgaveaninitialdischargecapacityof160mAh·g-1forthepowderswithNaCladditionwhile70mAh·g-1forthepowderswithheptane.
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简介:有5-8nm的尺寸的做Eu的GaOOHnanoparticles被热水的方法作为表面活化剂用钠dodecylbenzenesulfonate(SDBS)准备。做Eu的-Ga2O3和-Ga2O3被退火进一步制作GaOOH:Eu然后由X光检查衍射(XRD)描绘了,传播电子显微镜学(TEM)和光致发光(PL)。TEM结果显示出那monodisperse做Eu3+的GaOOHnanoparticles形式然后变换进通过退火的做Eu3+的-Ga2O3和-Ga2O3GaOOH:在600和900点的Eunanoparticles?????????????????@
简介:TherelationshipofelectricalpropertiesofMn-dopedBa0.92Ca0.08TiO3PTCR(positivetemperaturecoefficientresistance)ceramicswithtwosinteringscheduleswasdiscussed.UsingTEM(transmissionelectronmicroscope)combinedwithEDS(energydispersiveX-rayspectrometer),theMnionsdistributedatgrainboundarieswereanalyzed.TheresultsshowthatthePTCReffectofMn-dopedPTCRceramicsismoredependentonthesinteringschedulethanthoseofMnfree.ThephenomenonmaybecausedbythevalencestatesvarianceofMnionssegregatedatthegrainboundaries.
简介:霍尔-埃鲁特铝电解槽需要一种新型的耐火材料来取代现有的凝固电解质构筑的炉帮。用两步烧结法制备的镁铝尖晶石作为潜在的候选材料,采用阿基米德排水法和扫描电镜研究镁铝尖晶石的致密化和晶粒长大。将所制备的试样在Na3AlF6-AlF3-CaF2-Al2O3电解质中腐蚀以评价其耐蚀性能。结果表明,用两步烧结法可制备高致密度(99.2%)和均匀显微结构的镁铝尖晶石。镁铝尖晶石对Na3AlF6-AlF3-CaF2-Al2O3电解质的腐蚀机理主要是镁铝尖晶石的溶解、氧化铝的形成和氟化物的扩散。两步烧结法制备的镁铝尖晶石具有良好的耐Na3AlF6-AlF3-CaF2-Al2O3电解质腐蚀性能。