简介:Byanalogueexperimentofexhaustgas,thesensitivecharacteristicsoftitaniatoair/fuelratiowasinvestigated.Theeffectsofsomeimpuri-tiesontheelectricconductivityofTiO2,thedeviationof(A/F)cfrom(A/F)sinnonequilibriumgassystemandtheself-catalyticoxidationofTiO2wereexplainedrespectively.Theeffectsofca-talyst,porosityandthicknessofsensorelementontheresponsetimewasalsoanalyzed.
简介:与直径40公里测试的裂口Hopkinson压力酒吧(SHPB)被用来与不同苍蝇灰内容调查设计似水泥的composites(ECC)的动态机械性质。包括变丑,精力吸收能力,紧张压力关系和失败模式的基本性质被讨论。ECC证明紧张率相关性和保留的更好的塑料与反应粉末水泥(RPC)和水泥相比流动在影响过程期间,但是批评压缩力量比RPC和水泥的低。PVA纤维的衔接的效果和苍蝇灰的增加能显著地改进ECC的变丑和精力吸收能力。随在ECC的苍蝇灰内容的增加,降低的静态、动态的压缩力量和动态增加因素提高了。因此,到会,不同工程需要,苍蝇灰的内容能是一个重要索引控制ECC的静态、动态的机械性质。
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:尼康公司发布一款兼容尼康FX格式数码单反相机的大光圈中远摄定焦镜头AF—S尼克尔105mmf/1.4EED。AF—S尼克尔105mmf/1.4EED大光圈中远摄定焦镜头,焦距105mm、最大光圈f/1.4,并且实现了自动对焦性能。105mmf/1.4的规格实现浅景深的背景虚化效果,同时拥有令人印象深刻的场景捕捉效果以及呈现美丽摄影表达的中远摄效果。另外。在从边缘区域开始的整体画面.该镜头可以高分辨率再现风景等场景.使用最大光圈时拍摄主体也能锐利呈现。良好的点图像还原性能使夜景中的点光源还原成清晰的点图像,而且失真和渗出较少。该镜头采用了3枚ED(低色散)玻璃镜片减轻色差,利用纳米结晶涂层有效降低鬼影和眩光。
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%。