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.
简介:Throughmeasuringthecoefficientoflinearexpansion,thestructureandpropertiesoftheLi2O-Al2O3-SiO2lowexpansionglassceramicscontainingB2O3arestudiedbyJRandXRD.ItisshoutnthattheIRmethodisefficientinthestudyoftheglass-ceramicsstructure.Thereisa"Boronabnormality"inthesystemwhichhasanimportantinfluenceonthepropertiesoftheglass-ceramics.
简介:SiO2-B2O3-Al2O3-CaO在低sintering温度使契约成玻璃,高力量被讨论。FTIR和XRD分析被用来与铝的不同内容描绘基本使成玻璃的契约的结构。弯曲力量和热扩大系数也被测试。同时,在660光线衍射(XRD)的sintering温度的合成标本的微观结构,扫描电子显微镜(SEM)分析和其它工具。结果证明分别地,钾和磷的溶解率在95.64wt%lessthan的一种谷物尺寸的条件下面是70wt%和93.7wt%0.074公里,9.78gg-1硫磺的酸,0.5gg-1铵氟化物,160桴???瑳畲瑣牵獥椠?慭湩慴湩摥映吗??
简介:TheantibacterialeffectofcarryingsilverB2O3-SiO2-Na2Oglassmaterialwasstudiedbymeansofantibacterialring,nephelometery,MICvalue,thinfilmattachmentandmicrocalorimetry,respectively.TheexperimentalresultsoffivekindsofantibacterialtestmethodsarealmostidenticalandcanverifythatcarryingsilverB2O3-SiO2-Na2Oglassmaterialexertsanexcellentantibacterialperformance.Antibacterialringandnephelometeryaresimple,quick,buttheprecisionisrestrictive.MICvalue,thinfilmattachmentmethodandmicrocalorimetrycanquantitativelycomparetheantibacterialeffectsoftheantibacterialglassmaterial.Comparedwiththetraditionalmicrobetestmethods,themicrocalorimetrycananalyzetheinhibitingeffectofthecell'sgrowthandmetabolismontheantibacterialglassmaterialbymonitoringthethermaleffectcontinuouslyandautomatically.
简介:ThemechanismoftheinterfacialreactionofAl2O3/mediumMnsteelcontainingNbwasstudiedbymeansoftheobservationontheinterfacialreactionphenomenonofAl2O3/mediumMnsteel,andtheanalysesontheinterracialphases.TheresultsshowthatwhenT≥1550℃,theinterfacialreac-tionofAl2O3/mediumMnsteelcontainingNbhappened.InthemediumMnsteelmatrix,NbexistsintheformofNbC.NbCarethenucleatingbaseofCOgasbubbles.
简介:以便得到TiB2-Al2O3的同质的混合物和协议,一个表面修正方法被用来准备nano规模的杂交Al2O3涂的TiB2粒子。PE蜡粒子是第一到由杂交,然后nano规模Al2O3粒子的TiB2粒子上涂又是涂的到由PE蜡粒子涂的TiB2的表面上。SEM,TEM和版本被用来描绘同样收到的核心/壳粒子和它的协议的微观结构。试验性的结果显示出那粒子规模TiB2和Al2O3的同质的分散能不仅在混合粉末而且在使脱蜡的协议被形成。协议当时是由煤气压的sintering(GPS)的sintered。物件顶端的装饰物产品显示出与参考样品由正常方法制作了作比较的改进技工性质。
简介:Inordertorealizetheco-firingwithAg/Pdelectrodesinmultilayerdevices,Pb(Zn1/3Nb2/3)1-,-yZrxTiyO3(0.25<x<0.35,0.25<y<0.35)piezoelectricceramics(hereafterdesignatedPZN-PZT)modifiedbyLa2O3hasbeenpreparedbyconventionaltechniquewithsinteringtemperaturefrom1100℃to1140℃.X-raydiffractionpatternsdemonstratedthatpureperovskitephasewasobtained.Secondaryelectronimage(SEI)showedthatcrystallinegrainsinceramicswerewellgrown.d33ofmanufacturedsamplewasashighas560×10-12C/N.kpwasabout0.61andtgδabout30×10-3.TheexistenceofliquidphaseexaminedbyelectrondiffractioninPZN-PZTsampleisbeneficialtosinteringoftheceramic.
简介:Theimplantedionrange,thedepthprofileandthefilmsttuctureoftheimplantedlayerwerestudied;thecarrierconcentrationandthemobilityweremeasured;theconductivitymechanismofthefilmimplantedFeintoAl2O3ceramicwasdiscussed.TheconclusionisthattheimplantedFe2+ionsmoveintoAl2O3latticeandreplaceAl3+toformsubs-titutionimpuritiessothattheionimplantedlat-tice,ascomparedwiththeoriginalone,presentsaneffectivenegativechargewhichformsanegativechargecenter.Avacancyisboundarroundit,andanacceptorisintroducedintheforbiddenband.
简介:以两种Al2O3-Al2TiO5复合粉体为原料经SPS烧结制备出Al2O3-Al2TiO5复相陶瓷。采用纳米结构复合粉体烧结而成的复相陶瓷有着较优的力学性能,特别是具有较高的断裂韧性和硬度,与其较小的晶粒尺寸相对应。干滑动摩擦磨损试验在4N和6N法向载荷下进行,结果表明,采用微米结构复合粉体烧结而成的复相陶瓷磨损表面较光滑,体积磨损量较小。在磨损试验中,纳米结构复合粉体烧结而成的复相陶瓷的破坏方式为沿晶断裂,有明显的晶粒拔出现象;微米结构复合粉体烧结而成的复相陶瓷呈不连续的微观断裂并产生塑性变形;同时,两种材料在摩擦磨损过程中都发生接触面的氧化和物质转移。
简介:Basedonthedifferenceofhydroxygroupconfigurationondifferentplanesofα-Fe2O3nanoparticles,usingthespecialadsorptionandcoordinationofphosphateonthe(001)planeofα-Fe2O3,well-crystallizedandwelldispersedα-Fe2O3nanodiskswithdiameterof150–200nmandthicknessof40–80nmweresynthesizedviaahydrothermalmethod.Themagneticpropertiesofsynthesizednanodiskswereinvestigated.Itwasfoundthatthenanodiskspossessedasaturationmagnetization(Ms)of0.38emu/g,aremanentmagnetization(Mr)of0.031emu/gandacoercivityof452.91Oeatroomtemperature.TheMrandcoercivityofsynthesizedα-Fe2O3nanodisksarehigherandtheMsislowerthanthoseofotherpreviouslyreportedα-Fe2O3nanostructures.
简介:MoleculardynamicssimulationusingauniversalforcefieldhasbeenemployedtodeterminethediffusioncoefficientsofO2andNa2SO4vaporintoB2O3andSiCfrom700Kto1273K,respectively.Einsteindiffusionwasobservedina250~300pssimulation.ThediffusioncoefficientfortheO2rangefromabout9.279×10-9cm2/sforB2O3to2.275×10-10cm2/sforSiCataloadingof32moleculespersimulationbox,thatfortheNa2SO4vaporrangefromabout9.888×10-7cm2/sforB2O3to1.837×10-10cm2/sforSiCataloadingof8moleculespersimulationbox.EnvironmentpropertiesofC/SiCcompositewillbeincreasedviatheB2O3preventingthediffusionofO2andNa2SO4vaporintothepyrolyticinterphaseandcarbonfibers.
简介:TiB2ceramicspowderwassynthesizedfromB2O3-TiO2-Mgsystem.TheeffectsofTiB2additionasdiluentonthecombustionsynthesisprocesswereinvestigated.TheresultsofthermodynamiccalculationandexperimentsshowthattheincreaseofTiB2contentrangingfrom0to20wt%canreducetheadiabatictemperatureTadfrom3100Kto2896KandcombustiontemperatureTcfrom2139Kto1621Krespectively.TheparticlesizeandhalfwidthoftheparticledistributionarealsoincreasedwiththeadditionofTiB2increasingfrom0to20wt%.ThecombustionproductisamixtureofTiB2,MgO,andotherintermediatephases.TheleachedproductcontainsmainlyTiB2,TiO2andTiN,anditsoxygencontentis7.77wt%.