简介:Novelcore-shellhydroxyapatite/chitosanbiocompositenanospheresweresynthesizedinamultipleemulsion.Themultipleemulsionwasaw/o/wemulsion,madeofdiammoniumphosphatesolutionasaninneraqueousphase,cyclohexaneasanoilphase,andcalciumnitratesolutionandchitosansolutionasanouteraqueous.Theformingmechanismofcore-shellspheresandtheinfluenceoftemperatureonthemorphologyofthenanosphereswereinvestigated.Thediameteroftheresultingcore-shellnanosphereswas100-200nmandthethicknessofthechitosanshellwasabout10nm.Anditconcludedthatatdifferentreactiontemperaturethemorphologiesoftheproductswouldbechanged.Thecore-shellnanosphereshavepotentialapplicationsforthedevelopmentofnewbiomedicalmaterials.
简介:Theindustrialmanufactureprocessesofthreekindsofrollcoreusedductileironshavebeeninvestigatedviasystematicalexperiments.EffectsoftheratioofC/Si,pigiron,nodularizerandalloyingmethodonthemicrostructureandmechanicalpropertiesoftheheavysectionductileironhavebeenanalyzed.IthasbeenfoundthatwhentreatedwithRE-MgplusSb,highqualitynodularcastingscanbeproducedevenifmuchantispheroidizingalloyelementsareincludedinthepigiron.ThealloyelementSbplayedanimportantroleinthecontrolofgraphitemorphology.
简介:Mechanicalpropertiesofepoxyresinwereinvestigatedbyaddingcore-shellelasticparticles(CSEP).Theresultsindicatedthatoptimizedcore-shellratiowas60/40andtheloadingvolumeofCSEPwas10phr(perhundredpartsofepoxyresinbyweight).Theimpactstrengthofmodifiedsystemsincreasedapparentlywiththedecreaseofcoresizes.However,theshearingstrengthchangedgentlywiththeparticlesizes.CSEPwithlightlycrosslinkedrubberycoreshowedmoreeffectivenessontoughnessthanothers.Withsolutionblending,CSEPcouldbedispersedinepoxymatrixwell,andthemorphologiesofdispersedrubberdomainswerecontrolledperfectlybyCSEPwhosestructurewaspredesigned.Acavitation-shearingbandtoughnessmechanismwasobservedfromtheSEMmicrographsoffracturesurface.Italsowasfoundthatthedeformingtemperature(DT)ofmodifiedepoxydidnotdeclineapparently.
简介:Themicrostructureofthelasermelted1.0%Ctoolsteelhavebeeninvestigated.Theregionaffectedbythelasercanbesubdividedinto3zones,whichconsistofameltedregionatthesurface,azonewithsolidstatetransformationandtheareaadjacenttotheunaffectedsubstratewherecementiteisslightlydissolved.Themeltedzonepossessedacellulargrowthmorphologyconsistingofausteniteandmartensite.Thecarboncontentoftheaustenitewasmeasuredtobeover1wt-%.Agreatdealofretainedausteniteandtwinnedmartensitewerefoundinthefirsttwozones(themeltedandsolidtransformed).
简介:用x射线衍射、光学显微镜、扫描电镜和能谱等分析Al-10Ce中间合金的相组成和微观形貌,研究Al-10Ce中间合金对α-铝的变质处理效果及对α-铝的长效性变质和重熔稳定性变质,并与钠盐变质进行了对比。结果表明:Al-10Ce中间合金用量对变质效果的影响很大,Al-10Ce中间合金用量为0.30%左右时达到最佳变质效果,用量少变质效果差,用量过多则形成过变质。用Al-10Ce中间合金对α-铝进行变质,可取得极好的变质效果,变质持续时间比钠盐变质剂更长久且具有更好的重熔稳定性。