简介:二维(2D)有multilayered质地的碳/碳(C/C)composites,特别与不同厚度高度粗糙(HT)pyrocarbon层,被等温的、等压的化学蒸汽渗入(CVI)准备技术。C/Ccomposites的机械性质上的矩阵微观结构的影响被极化的轻显微镜学调查,扫描电子显微镜学和三点的弯曲测试。结果证明有多层粗糙的pyrocarbon矩阵的样品与纯媒介粗糙的结构比那件拥有更高曲折的力量,它被归因于多重裂缝偏转并且在HT层以内的在不同粗糙的pyrocarbon层之间并且在亚层之间的界面的滑动。HTpyrocarbon层的厚度的增加改进样品的粘性并且在伪塑料行为显示破裂。
简介:Throughmeasuringthecoefficientoflinearexpansion,thestructureandpropertiesoftheLi2O-Al2O3-SiO2lowexpansionglassceramicscontainingB2O3arestudiedbyJRandXRD.ItisshoutnthattheIRmethodisefficientinthestudyoftheglass-ceramicsstructure.Thereisa"Boronabnormality"inthesystemwhichhasanimportantinfluenceonthepropertiesoftheglass-ceramics.
简介:One-dimensional(1D)nanomaterialsandnanostructureshavereceivedmuchattentionduetotheirpotentialinterestforunderstandingfundamentalphysicalconceptsandforapplicationsinconstructingnanoscaleelectricandoptoelectronicdevices.Zincsulfide(ZnS)isanimportantsemiconductorcompoundofII-VIgroup,andthesynthesisof1DZnSnanomaterialsandnanostructureshasbeenofgrowinginterestowingtotheirpromisingapplicationinnanoscaleoptoelectronicdevices.Thispaperreviewstherecentprogresson1DZnSnanomaterialsandnanostructures,includingnanowires,nanowirearrays,nanorods,nanobeltsornanoribbons,nanocables,andhierarchicalnanostructuresetc.Thisarticlebeginswithasurveyofvariousmethodsthathavebeendevelopedforgenerating1Dnanomaterialsandnanostructures,andthenmainlyfocusesonstructures,synthesis,characterization,formationmechanismsandopticalpropertytuning,andluminescencemechanismsof1DZnSnanomaterialsandnanostructures.Finally,thisreviewconcludeswithpersonalviewstowardsfutureresearchon1DZnSnanomaterialsandnanostructures.
简介:Thebovinehydroxyapatite(BHA)wasappliedtopreparebiologicaltissueengineeringscaffoldsbythemethodofextrusionfreeforming.Toachievethisgoal,BHAwereaddedtosodiumalginate(SA)solutiontoformaslurrysysteminappropriateproportion.Theresultingmixtureswerefabricatedtobeakindofcontrollableandporousscaffoldsfollowedwithcross-linkingin5%calciumchloride(CaCl2)solutionfor24h.Afterthat,thescaffoldsweresinteredinairat1000,1100,1200and1300℃for5h.Scanningelectronmicroscopy(SEM)andX-raydiffraction(XRD)studieswereperformedonthescaffoldstoanalyzeitsmicrostructureandconstituent.Toexploretheeffectofsinteringtemperatureonscaffolds,thecompressivestrength,volumeshrinkageandwaterabsorptivityofBHA-SAcompositescaffoldsaftersinteringwereinvestigated.TheresearchtestsindicatedthefeasibilityofapplyingBHApowderto3Dprinting.Besides,thescaffoldssinteredinarespectivelylowertemperaturepossessmuchmoreporesandperformedhigherwaterabsorptivity,whichmeansbettercellularaffinity.Andscaffoldssinteredbetween1100and1200℃presentshighercompressivestrength.
简介:Amathematicalmodelforthethree-dimensionalsimulationoffreedendriticgrowthandmicrostructureevolutionwasdevelopedbasedonthegrowthmechanismofcrystalgrainsandbasictransferequationssuchasheat,massandmomentumtransferequations.Manyfactorsincludingconstitutionalundercooling,curvatureundercoolingandanisotropy,whichhadvitalinfluencesonthemicrostructureevolution,wereconsideredinthemodel.SimulatedresultsshowedthatfinalmicrostructuralpatternsandfreedendriticgrowthcouldbepredictedreasonablyandcalculatedresultswerecoincidentwithexperimentalThesimulatedresultsoffreedendriticgrowthindicatedthatthestrengthofanisotropyhassignificanteffectsonfreedendriticgrowth,dendriteprofile,microsoluteandtemperaturedistribution.Thedendriticgrainprofileswithfully-grownparallelsecondaryarmtendtobeformedattheintensiveanisotropy,whilenearoctahedralgrainprofileswithsmallprotuberancesofsurfaceatlowstrengthofanisotropy.Thesimulatedresultsoffreedendriticgrowthalsoindicatedthattherearesmallmoltenpoolsleftininterdendriticareas.Thisishelpfultounderstandthefundamentaloftheformationofmicrostructurerelateddefectssuchasmicrosegregationandmicroporosity.
简介:TheelectronicstructuresofCuS2,CuSe2andCuTe2withpyritestructures,withintheframeworkthedensity-functionaltheoryhavebeeninvestigated.ThecalculatedresultsexplainedtherecentexperimentalresultswhichshowthatthereisnoclearindicationofstrongelectroncorrelationsintheelectronicpropertiesofCupyrites,duetothedominantchalcogenpcharacterratherthandcharacteristicofCuattheFermilevel.
简介:TheantibacterialeffectofcarryingsilverB2O3-SiO2-Na2Oglassmaterialwasstudiedbymeansofantibacterialring,nephelometery,MICvalue,thinfilmattachmentandmicrocalorimetry,respectively.TheexperimentalresultsoffivekindsofantibacterialtestmethodsarealmostidenticalandcanverifythatcarryingsilverB2O3-SiO2-Na2Oglassmaterialexertsanexcellentantibacterialperformance.Antibacterialringandnephelometeryaresimple,quick,buttheprecisionisrestrictive.MICvalue,thinfilmattachmentmethodandmicrocalorimetrycanquantitativelycomparetheantibacterialeffectsoftheantibacterialglassmaterial.Comparedwiththetraditionalmicrobetestmethods,themicrocalorimetrycananalyzetheinhibitingeffectofthecell'sgrowthandmetabolismontheantibacterialglassmaterialbymonitoringthethermaleffectcontinuouslyandautomatically.
简介:Newvisibletransparent,UVabsorption,andhighinfraredreflectionpropertieshavebeenrealizedbydepositingmultilayerSiO2/ZnO:Al/CeO2-TiO2/SiO2filmsontoglasssubstratesatlowtemperaturebyradiofrequencymagnetronsputtering.OptimumthicknessofSiO2,ZnO:Al(ZAO)andCeO2-TiO2(CTO)filmsweredesignedwiththeaidofthinfilmdesignsoftware.Thedegreeofantireflectioncanbecontrolledbyadjustingthethicknessandrefractiveindex.TheouterSiO2filmcandiminishtheinterferencecoloringandincreasethetransparency;theinnerSiO2filmimprovestheadhesionofthecoatingontheglasssubstrateandpreventsCa2+,Na+intheglasssubstratefromenteringtheZAOfilm.Theaveragetransmittanceinthevisiblelightrangeincreasesbynearly18%-20%,ascomparedtodoublelayerZAO/CTOfilms.Andthefilmsdisplayhighinfraredreflectionrateofabove75%inthewavelengthrangeof10-25μmandgoodUVabsorption(〉98%)properties.Thesesystemsareeasytoproduceonalargescaleatlowcostandexhibithighmechanicalandchemicaldurability.ThetriplefunctionalfilmswithhighUVabsorption,antireflectiveandhighinfraredreflectionratewilladapttoapplicationinflatpaneldisplayandarchitecturalcoatingglass,automotiveglass,withdiminishinglightpollutionaswellasdecreasingeyefatigueandincreasingcomfort.
简介:Inpursuingexcellentsupercapacitorelectrodes,wedesignedaseriesofM0S2/C0S2compositesconsistingofflower-likedMoS2andoctahedron-shapedCoS2throughafacileone-stephydrothermalmethodandinvestigatedtheelectrochemicalperformanceofthesampleswithvarioushydrothermaltime.Duetothecouplingoftwometalspeciesandabigamountofwell-developedCoS2andMoS2,theresultsindicatedthattheMoS2/CoS2compositeselectrodesexhibitedthebestelectrochemicalperfor-mancewithalargespecificcapacitanceof490F/gat2mV/sor400F/gat10A/gamongallsamplesasthehydrothermaltimereached48h(MCS48).Furthermore,theretentionofMCS48is93.1%after10000cyclesat10A/g,whichmanifeststheexcellentcyclingstability.TheoutstandingelectrochemicalperformanceofMCS48indicatesthatitcouldbeaverypromisingandnovelenergystoragematerialforsupercapacitorsinthefuture.
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。