简介:体积的动态脆弱Zr64Cu16Ni10Al10合金的金属性的玻璃(BMG)被三点的横梁弯曲学习方法。脆弱参数mforZr64Cu16Ni10Al10BMG被计算在高温度是24.5,它意味着液体是一强壮“液体,当时在液体是的工具的低温度是13.4一超级强壮”液体。在supercooled区域的Zr64Cu16Ni10Al10BMG的动态行为经历一对超级强壮的转变强壮。到我们的知识,是第一次strong-to-superstrong转变在金属性的玻璃里被发现。用散布实验的小角度X光,我们发现这转变被假定与在supercooled液体的一个阶段分离过程有关。
简介:Meltsofleadbismuthgallatecompositionsarehighlycorrosiveandattackoncruciblesofdifferentmaterials.Inthepresentstudy,corrosionbyabaseglass(50PbO-30Bi2O3-20Ga2O3inmolefraction)meltedusingdifferentcruciblesandtheeffectonUV-VISandIRedgeswerestudied.Bymeltingthebaseglassinplatinum/2%rhodium,goldzirconiaandaluminacruciblesshowedlesseffectontheIRedgeandthereforeshiftedtheinfrarededgetolongerwavelength,whereassilicacruciblecontaminatedtheglass,causingaseveredeteriorationintheinfraredandhenceshiftedinfrarededgetomuchshorterwavelength.IntheUV-VISregion,baseglassmeltedinplatinum/2%rhodiumcrucibleshiftedtheedgetothelongestwavelengthwhereassilicacrucibleshiftedtheedgetoshorterwavelength.Thecontaminantsfromgold,zirconiaandaluminacruciblescausedtheUV-VISedgeofthebaseglasstoliebetweenthetwoextremesofPt/2%RhandSiO2crucibles.Theglassesmeltedinabovementionedcrucibleswerealsocharacterizedwithinductivelycoupledplasmaspectroscopy(ICP)analysistomeasurethelevelofcontaminationfromthecrucibles.Dependinguponcrucibleused,thecolorsofglassesobtainedrangedfromredtoyellow.
简介:InordertoimprovethemechanicalpropertiesofSiO2aerogel-glassfibercomposites,effectsofdifferentsolvents(cyclohexane,n-hexane,ethanol,acetone)anddifferentdispersingmodes(planetaryballmilling,ultrasonicdispersionandmechanicalstirring)anddispersingduration(10-40min)onthedispersionofchoppedalkali-freeglassfiberbundleswerestudiedtodeterminethebestdispersionprocess.Onthisbasis,thematerialswerebatchedaccordingtothemassfractionofSiO2aerogelpowdertochoppedalkalifreeglassfiberbundlesof90:10,andacertainamountofzincoxidelight-screeningagentandphenolicresinbinderwereadded.SiO2aerogelglassfibercompositespecimenswerepreparedbydirectaddingchoppedalkalifreeglassfiberbundlesandpre-dispersedchoppedalkalifreeglassfiberbundles,respectively.Thecoldcrushingstrengthandthethermalconductivityatdifferentsurfacetemperatures(300,400,500and600℃,respectively)ofthespecimensweremeasured.Theresultsshowthat:(1)theoptimumdispersionprocessofchoppedalkali-freeglassfiberbundlesisusingethanolassolventandmechanicalstirringfor30min;(2)pre-dispersionofchoppedalkali-freeglassfiberbundleshaslittleeffectonthethermalconductivityofSiO2aerogel-glassfibercompositesbutcanimprovethecoldcrushingstrength.
简介:Inthiswork,ahybridstructureconsistingofamulticomponentgermanateglassmicrospherecontainingbismuthasagainmediumisproposedandpresented.Thebismuth-dopedgermanateglassmicrosphereswerefabricatedfromaglassfibertipwithnoprecipitationofthebismuthmetal.Couplingwithafibertaper,thebismuth-dopedmicrospheresingle-modelaserwasobservedtolaseataround1305.8nmusing808nmexcitation.Thelowthresholdofabsorbedpumppowerat215μWmakesthismicrolaserappealingforvariousapplications,includingtunablelasersforarangeofpurposesintelecommunication,biomedical,andopticalinformationprocessing.
简介:Weinvestigatehigh-modulusdegradablematerialsintendedtoreplacemetalsinbiomedicalapplications.Thesearetypicallycompositescomprisingapolylactide(PLA)matrixreinforcedwithphosphateglassfibres,whichprovidereinforcementsimilartoE-glassbutareentirelydegradableinwatertoproduce,principally,calciumphosphate.Wehavemadecompositesusingavarietyoffibrearchitectures,fromnon-wovenrandommatstounidirectionalfibretapes.Flexuralpropertiesintheregionof30GPamodulusand350MPastrengthhavebeenachieved-directlycomparabletoquotedvaluesforhumancorticalbone.Incollaborationwithothergroupswehavebeguntoconsiderthedevelopmentoffoamedsystemswithstructuresmimickingcancellousboneandthishasshownsignificantpromise.Thefibresinthesefoamedstructuresprovideimprovedcreepresistanceandreinforcementoftheporewalls.Todatethematerialshaveexhibitedexcellentcellularresponsesinvitroandfurtherstudiesareduetoincludeconsiderationofthesurfacecharacterofthematerialsandtheinfluenceofthisoncellinteraction,bothwiththecompositesandtheglassfibresthemselves,whichshowpromiseasastandaloneporousscaffold.