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简介：本文介绍了PVA材料高阻隔性能的机理,对常见的涂布型PVA阻隔膜的耐水改性研究、涂布复合工艺及其制作方法进行了综述,并对已经产业化的涂布型PVA阻隔包装薄膜作了简要阐述。文中将涂布型PVA阻隔膜和商品化的EVOH和PVDC阻隔复合膜进行比较,涂布型PVA阻隔薄膜阻隔性能优异、价格低廉、绿色环保,具有更加广阔的市场前景。

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简介：Themicrostructureevolutionandphasecompositionofanα+βtitaniumalloy,Ti-3Al-5Mo-4.5V(wt.%),havebeeninvestigated.Electronprobemicroanalysis(EPMA)quantitativeresultsmanifestthatthestabilityofβphasedecreaseswithincreasingquenchingtemperature,whichisinfluencedbythesignificantvariationofβ-stabilizingelementsconcentration.Detailedmicrostructureanalysisshowsthattheβ→ωphasetransformationdoesoccurwhenquenchingat750℃and800℃.Theω-reflectionschangefromincommensurateω-spots(750℃)toidealω-spots(800℃)astheβstabilityofthealloydecreases.Furtherthedecreaseofβphasestabilityencouragestheformationofathermalα"martensite,whichhasthefollowingorientationrelationships:[111]β//[110]α",[100]p//[100]α"and[-110]p//[00-1]α"withrespecttotheβmatrix.

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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.

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简介：WithFe(NO3)39H2OandBi(NO3)35H2Oasrawmaterials,differentsillenite-typecompoundsandelementalbismuthwerepreparedbyafacileone-potsolvothermalmethodusingH2O,C2H5OH,(CH2OH)2andC3H8O3assolvents,respec-tively.Thestructure,morphology,elementalcompositionsandpropertiesofsampleswereexaminedbyXRD,SEM,TEM,ICP,XPS,N2adsorptionanddesorption,UV-visDRSandPL.ThephotocatalyticactivitiesofdifferentsampleswereevaluatedbythephotodegradationofRhBundervisible-lightirradiation(λ>400nm),andresultsshowthatBi36Fe2O57preparedusingC2H5OHasthesolventownstheoptimumperformance.Inordertoexplorethereactionmechanism,anadditionalexperimentwasdesignedtoinvestigatethemainactivespeciesduringthephotodegradationprocessviadissolvingdifferenttrappingagentsinthereactionsolutionbeforelightirradiation.TheresultsshowthatsuperoxideradicalanionsplayamajorroleinthissystemsincetheRhBdegradationwassignificantlysuppressedaftertheadditionofbenzoquinone.