简介:PalladiumcatalystsaresupportedonTiO2,ZrO2,Al2O3,Zr0.5Al0.5O1.75andTiO2-Zr0.5Al0.5O1.75preparedbyco-precipitationmethod,respectively.CatalyticactivitiesformethaneandCOoxidationareevaluatedinagasmixturethatsimulatedtheexhaustfromlean-burnnaturalgasvehicles(NGVs).Pd/TiO2-Zr0.5Al0.5O1.75performsthebestcatalyticactivityamongthetestedfivecatalysts.ForCH4,thelight-offtemperature(T50)is254℃,andthecompleteconversiontemperature(T90)is280℃;forCO,T50is84℃,andT90was96℃.Varioustechniques,includingN2adsorption-desorption,X-raydiffraction(XRD),H2-temperature-programmedreduction(H2-TPR),X-rayphotoelectronspectroscopy(XPS),andscanningelectronmicroscopy(SEM)areemployedtocharacterizetheeffectofsupportsonthephysicochemicalpropertiesofpreparedcatalysts.N2adsorption-desorptionandSEMshowthatTiO2-Zr0.5Al0.5O1.75expressesuniformnano-particlesandlargemeso-porediametersof26nm.H2-TPRandXRDindicatethatPdOiswelldispersedonthesupportsandstronglyinteractedwitheachother.TheresultsofXPSshowthattheelectrondensityaroundPdOandtheproportionofactiveoxygenonTiO2-Zr0.5Al0.5O1.75aremaximaamongthefivesupports.
简介:Ag-TiAlintermetallicalloy,Tie45Ale2Nbe2Mn(at.%)e0.8vol.%TiB2,hasbeenprocessedfromgasatomizedprealloyedpowderbyfieldassistedhotpressing(FAHP).Aninitialanalysisoftheprealloyedpowderhelpedontheunderstandingoftheintermetallicsinteringbehavior.Atomizedpowderconsistedofametastablephasethattransformedintoa2tgequilibriumphasesbythermaltreating.Differentpowderparticlemicrostructureswerefound,whichinfluencethemicrostructuredevelopmentoftheFAHPg-TiAlmaterialdependingonthesinteringtemperature.Duplex,nearlylamellarandfullylamellarmicrostructureswereobtainedatthesinteringtemperaturesabove1000C.Lowerconsolidationtemperatures,below1000C,ledtotheformationofanAlrichphaseatpowderparticleboundaries,whichisdeleterioustothemechanicalproperties.Highcompressiveyieldstrengthof1050MPawasobservedinsampleswithFAHPduplexmicrostructuresatroomtemperature.Whereasnearlylamellarandfullylamellarmicrostructuresshowedyieldstrengthvaluesof655and626MPaatroomtemperatureand440and425MPaat750C,respectively,whicharesuperiorincomparisontosimilaralloysprocessedbyothertechniques.Theseexcellentpropertiescanbeexplainedduetothedifferentvolumefractionsofthea2andgphasesandtherefinementofthePMmicrostructures.
简介:目的观察早期胃癌组织中GTP酶激活蛋白SH3功能区结合蛋白G3BP1和G3BP2的表达变化并探讨其意义。方法选择早期胃癌组织89例和正常对照组织35例,采用免疫组织化学方法检测两组G3BP1蛋白和G3BP2蛋白的表达情况。结果早期胃癌组和正常组G3BP1的阳性率分别为87.64%和60.00%,G3BP2阳性率分别为86.51%和54.28%,两组比较差异有统计学意义(P=0.000,0.000);早期胃癌G3BP1和G3BP2的表达均与幽门螺杆菌感染相关(P=0.000);早期胃癌组织中G3BP1与G3BP2表达呈正相关(rs=0.252,P=0.017)。结论早期胃癌组织中G3BP1和G3BP2呈高表达,可能与幽门螺杆菌感染紧密相关,两指标异常表达可能在早期胃癌的发生和发展中起重要作用。
简介:工业和信息化部12月25Et发布《关于向民间资本开放宽带接人市场的通告》(以下简称《通告》),《通告》称,鼓励民间资本以多种模式进入宽带接入市场。一是鼓励民营企业建设宽带接入网业务所需的基础设施.并以自有品牌为用户提供宽带上网服务。二是鼓励民营企业以资本合作、业务代理、网络代维等形式与基础企业开展合作,分享收益。三是鼓励拥有互联网接入服务业务(ISP)经营许可证的民营企业,从基础电信企业租用接入网络资源,以自有品牌为用户提供宽带上网服务。《通告》对基础电信企业和民营企业分别提出了要求,并就第一种开放模式制定发布了《宽带接入网业务开放试点方案》。
简介:Heavyionbeamsaregenerallyrecognizedasoneofpowerfulmutagensinplantbreedingtogeneratenewmutantswithidealorusefulagronomiccharacters[1].12C6+ionbeams(80MeV/u)acceleratedbyHeavyIonResearchFacilityinLanzhou(HIRFL)wereusedtoirradiatewheatsamples,oneofthemajorwheatvarietiesinQinghaiprovince,namedGaoyuan448.Theradiationdosesrangedfrom10to200Gy.Theirradiatedsamples,controls,andanothermajorwheatvarietynamedAbowereplantedinfarmlocatinginLeducountyofQinghaiprovincein2014.
简介:目的:探讨3D腔镜辅助甲状腺手术的可行性与安全性。方法2014年1-4月,选择甲状腺单双侧良性病变、甲状腺微小癌以及甲状旁腺病变10例,在3D腔镜辅助下,经颈前胸骨凹上方约一横指处2-4cm弧形切口行局部病灶或患侧腺叶切除,其中2例术中冰冻病理证实甲状腺微小乳头状癌,行患侧Ⅵ区淋巴结清扫。结果10例手术均在3D腔镜辅助下顺利完成,术中无异常出血,无中转开放手术,手术时间30-90min,(61.8±22.4)min;术中出血量1.3-93.0g,中位数5.2g。术后随访1-4个月,未出现喉返神经、喉上神经和甲状旁腺损伤等并发症。结论3D腔镜辅助行甲状腺手术安全、可行,相对于2D技术,空间立体感强,更有利于局部精细解剖,有利于功能保护。