简介:Aninnovativeapproachhasbeendevelopedtofabricatereticulatedporousceramics(RPCs)withuniformmacrostruc-turebyusingthepolymericspongeasthetemplates.Inthisapproach,thecoatingprocesscomprisesoftwostages.Inthefirststage,thethickerslurrywasusedtocoatuniformlythespongesubstrate.Thegreenbodywaspreheatedtoproduceareticulatedperformwithenoughhandlingstrengthafterthespongewasburnedout.Inthesecondstage,thethinnerslurrywasusedtocoatuniformlytheperform.Thepopulationofthemicroscopicandmacroscopicflawsinthestructureisreducedsignificantlybyrecoatingprocess.Afewfilledcellsandcellfacesoccurinthefabricationandthestrutswerethickened.AstatisticalevaluationbymeansofWeibullstatisticswascarriedoutonthebendstrengthdataofRPCs,whichwerepreparedbythetraditionalapproachandinnovativeapproach,respectively.TheresultshowsthatthemechanicalreliabilityofRPCsisimprovedbytheinnovativeapproach.Thisinnovativeapproachisverysimpleandcontrolledeasily,andwillopenupnewtechnologicalapplicationsforRPCs.
简介:Byanalogueexperimentofexhaustgas,thesensitivecharacteristicsoftitaniatoair/fuelratiowasinvestigated.Theeffectsofsomeimpuri-tiesontheelectricconductivityofTiO2,thedeviationof(A/F)cfrom(A/F)sinnonequilibriumgassystemandtheself-catalyticoxidationofTiO2wereexplainedrespectively.Theeffectsofca-talyst,porosityandthicknessofsensorelementontheresponsetimewasalsoanalyzed.
简介:Samplesofacobalt-basedalloythatunderwentasurfacetreatmentwereevaluated.Thesamples,whichwereobtainedbycastingalloyASTMF75,weregroundandpolishedononesideuntilamirrorfinishwasobtained.Thesampleswereencapsulatedinwollastonite(W)usinguniaxialpressure,treatedat1220℃for1handsubsequentlytemperedinwater.Thecharacterisationofthesampleindicatedthatpartoftheceramicencapsulatingmaterialwasmechanicallyincorporatedonthemetallicsurfacebygrowthoftheoxidelayerofthealloy.Afterthermaltreatment,aseriesofspecimensweresubmergedinasolutionwith5-foldsimulatedbodyfluid(5SBF)for3,5and21days.Characterisationbyscanningelectronmicroscopy(SEM),energydispersivespectroscopy(EDS)andX-raydiffraction(XRD)indicatednucleationandgrowthofahomogenouslayerofapatite,beginningonthethirddaywhenthesamplewassubmerged.
简介:Thestatusandthevariationofelectricalresistanceofimpactedcarbonfiber/epoxy-matrixcompositeswerestudiedbyultrasonicF-scanandelectricalresistancemeasurementTheexperimentalresultsshowsthatimpactdamageenergythresholdvalueofcarbonfabric/epoxy-matrixcompositescandeterminebyusingultrasonicF-scan.Whentheimpactenergyexceedsthethresholdvalue,damageisgeneratedincomposites.Electricalresistanceofimpactedcompositesischangedowingtothecontactofeachcarbonfiberunitincomposites,whichcauseachangeoftheseries-parallelinconductors.Theveracityofdetectingimpactdamageincompositescanbeimprovedinthiscase.
简介:以KF、SbCl3和SnCl2为原料配制乙醇溶胶,通过在Ti基底上涂胶、干燥、预热处理和煅烧等工艺制备出了F—Sb-SnO2/Ti复合电极。以F—Sb—SnO2/Wi复合电极为阳极,镍片为阴极,施加恒电压观测甲基橙电解液的脱色变化,在正交设计试验基础上,考察溶胶涂层数、煅烧温度、掺杂F离子的浓度等因素对甲基橙降解率的影响,结果表明,固定电解参数电压3V,甲基橙浓度50mg/L,添加荆h(Ⅲ)浓度110mg/L,溶液pH=l,优化的溶胶涂层数9,煅烧温度为773K,溶胶中维持Sn/Sb摩尔比9/1时,优化的KF掺杂摩尔比为0.5时,电解75min,甲基橙的降解率达93%。