学科分类
/ 25
500 个结果
  • 简介:HighactiveandstablegoldcatalystssupportedoncrystallineFe2O3andCeO2/Fe2O3werepreparedviathedeposition-precipitationmethod.ThecatalystwithaAuloadof1.0%calcinedat180°CshowedaCOconversionof100%at-8.9°C,whileAu/CeO2/Fe2O3convertedCOcompletelyat-16.1°C.Evenhavingbeencalcinedat500°C,Au/Fe2O3stillexhibitedsignificantcatalyticactivity,achievingfullconversionofCOat61.6°C.ThecatalystwithalowAuloadof0.5%couldconvertCOcompletelyatroomtemperatureandkepttheactivityunchangedforatleast150h.N2adsorption-desorptionmeasurementsshowthatthecrystallinesupportspossessedahighspecificsurfaceareaofabout200m2/g.CharacterizationsofX-raydiffractionandtransmissionelectronmicroscopyindicatethatgoldspecieswerehighlydispersedasnanoorsub-nanoparticlesonthesupports.Evenafterthecatalystwascalcinedat500°C,theAuparticlesremainedinanano-sizeofabout6―10nm.X-rayphotoelectronspectrarevealthatthesupportedAuexistedinmetallicstateAu0.ThemodificationofAu/Fe2O3byCeO2provedtobebeneficialtotheinhibitionofcrystallizationofFe2O3andthestabilizationofgoldparticlesindispersedstate,consequentlypromotingcatalyticactivity.

  • 标签: 金催化剂 CO氧化 氧化铁 Au/Fe2O3 去甲肾上腺素 X射线光电子能谱
  • 简介:AsimpleandefficientcascadeMichael/cyclizationreactionof3-aminoindolin-2-oneswithenones/enalswasidentifiedforthesynthesisofpotentiallybiologicallyactive3’,4’-dihydrospiro[pyrrol-3,2’-oxindoles],usingDBUasanefficientcatalystandethyleneglycolasanenvironmentallybenignsolvent.Morediverse3’,4’-dihydrospiro[pyrrol-3,2’-oxindoles]analoglibrarieswerepreparedingoodyields(upto97%).Thestructureof3’,4’-dihydrospiro[pyrrol-3,2’-oxindoles]wasconfirmedbymassspectrometryanalysis,NMRanalysisandsinglecrystalX-raydiffraction.Themainadvantagesofthismethodincludetheavailabilityofstartingmaterials,simpleexperimentaloperation,shortreactiontime,aswellashighyieldsobserved.

  • 标签: 环化反应 鞘氨醇 迈克尔 二氢 吲哚 烯酮
  • 简介:ThecomplexK3H4GeW9V3O40·8H2OcrystallizedinamonocliiniesystemwithspacegroupP2,Mr=2784.67,a=11.099(3),b=16.452(4),c=13.534(4),β=108.14°,Z=2,V=2348.493,F(000):2456,μ=239.7cm-1,De=3.932g/cm3.ThefinalR=0.083for4528non-zeroreflexions.ThestructureofanionsGeW9V3O40andGeW9O34belongstoA--type.

  • 标签: belongs crystallized STIRRING tetra slightly SUBSTITUTION
  • 简介:一系列5-phenyl-3H-spiro[indoline-3,2-[1,3,4]thiadiazol]-2-one类似物被综合并且他们的Bcl-2蛋白质禁止的活动被学习。铅混合物原来用荧光被识别基于极化的竞争有约束力的试金。在调查的10混合物之中,1k分别地显示出好有约束力的亲密关系到Bcl-xL和Mcl-1,与8.9mol/L和3.4mol/L的抑制常数。当复合1c完成了紧密的有约束力的亲密关系到Bcl-xL时(Ki=0.16mol/L),有潜力是新铅混合物。

  • 标签: 类似物 生物学评价 合成 苯基 吲哚 二氢
  • 简介:作者讨论等级3的稳定的向量捆的存在和分类,与3或4线性地独立的holomorphic节。这绑的所有的集合被ω3,d2和ω3表示,d2,分别地。我们的争论为两种捆的存在导致足够、必要的条件。因为它的矛盾,结论很有趣。最后,我们给结构上的ω3,42和完全的讨论的一个初步的分类。

  • 标签: 向量 代数曲线 计算方法 维数
  • 简介:AnaffordablesolutiontoTier-3RegionalCenter(RC)ispresentedinthistalk,asimpleprototypehasbeensetupforevaluationofthesystemperformance,thisprototypecanbeeasilyscaledtobiggerone.Asetofmeasurementshavebeenconductedinbothcomputerandnetworksystembehavioursinmultipleconcurrentlyrunningjobscontexts.Inthetalkthesemeasuredresultsaretalkedanddiscussed,includingsystemandnetworkeffectiveutilizationsandlimitations,andtheidentifiedbottlenecksindifferentnetworklayouts,andthecomparisonswithsimulation.

  • 标签: 高能物理实验 计算机网络 Tier-3系统 PC-Linux
  • 简介:Heavyionbeamsaregenerallyrecognizedasoneofpowerfulmutagensinplantbreedingtogeneratenewmutantswithidealorusefulagronomiccharacters[1].12C6+ionbeams(80MeV/u)acceleratedbyHeavyIonResearchFacilityinLanzhou(HIRFL)wereusedtoirradiatewheatsamples,oneofthemajorwheatvarietiesinQinghaiprovince,namedGaoyuan448.Theradiationdosesrangedfrom10to200Gy.Theirradiatedsamples,controls,andanothermajorwheatvarietynamedAbowereplantedinfarmlocatinginLeducountyofQinghaiprovincein2014.

  • 标签: MUTATION BREEDING IRRADIATED
  • 简介:Soilconsolidationwouldinducevariationsofitstransportcoefficientssuchashydraulicconductivityanddiffusioncoefficient.Thispaperpresentsastudyoftheinfluenceofbarrierconsolidationontransportcoefficients,anda3Dtransportmodelbasedonmixturetheoryisproposedfordescribingthelinersthatinvolvecirculardefectsinthegeomembrane.TheelastoplasticALPHAmodelisrevisedbyusingthespatiallymobilizedplane(SMP)criterionforsimulatingthedeformationofthesoils.Then,the3Dmodelcouplingthenonlinearconsolidationandcontaminantadvection-diffusionissolvedusingthefiniteelementsoftwareABAQUS.Theresultsshowthattheimportanceofreducingthedefectsizeinthegeomembraneandthelinerporositytocontrolthecontaminantconcentrationincrease.

  • 标签: 三维模型 迁移模型 污染物 输运系数 ABAQUS 土体固结
  • 简介:Theauthorsproposeanovelmethodfortransportingmulti-viewvideosthataimstokeepthebandwidthrequirementsonbothend-usersandserversaslowaspossible.Themethodisbasedonapplicationlayermulticast,whereeachendpointreceivesonlyaselectednumberofviewsrequiredforrenderingvideofromitscurrentviewpointatanygiventime.Thesetofselectedvideoschangesinrealtimeastheuser'sviewpointchangesbecauseofheadoreyemovements.Techniquesforreducingtheblack-outsduringfastviewpointchangeswereinvestigated.Theperformanceoftheapproachwasstudiedthroughnetworkexperiments.

  • 标签: 3DTV MULTI-VIEW video Application-layer multicast Join-latency
  • 简介:Anewkindofmonomerswassuccessfullysynthesizedbythereactionbetween2-chloromethylcycloketalandtrimethylsilylcyanide,followedbyringclosureanddehaiogenation.Polymerizationsofthemonomerswerecarriedoutinbenzenesolutionat80℃withbenzoylperoxideasinitiator.BoththestructuresofmonomersandpolymerswerecharacterizedbyIR,1HNMR,13CNMRandelementalanalysis.

  • 标签: Free RADICAL RING-OPENING POLYMERIZATION BIODEGRADABLE
  • 简介:TheIsodynetechniquebasedonthescatteredlightscanningfromathinlaserbeamcanbeusedtoobtaintheinformationinsidetheloadedobjectintheroomtemperaturenondestructively,soitisaverypowerfultechniquein3Dstressanalysis.Theproblemsarehowtointerprettheinformationandhowtogetsufficientinformationfromthefewinterferencefringe.Birefringencephaseshifttechniquecandistinguishthefringeordersautomaticallyandenrichtheinformationin256graylevelsbetweenmaximandminimlightintensity.InthepapertheIsodynebirefringencephaseshiftmethodwithanobliqueincidenceandequilibriumequationispresented,bywhichthe3DstressesinthemiddleplaneofaplatewithUshapenotchareseparatedsuccessfully.

  • 标签: 3D effect BIREFRINGENCE phase shift Isodyne