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500 个结果
  • 简介:ThecorrelationbetweenphasestructuresandsurfaceacidityofAl2O3supportscalcinedatdifferenttemperaturesandthecatalyticperformanceofNi/Al2O3catalystsintheproductionofsyntheticnaturalgas(SNG)viaCOmethanationwassystematicallyinvestigated.Aseriesof10wt%NiO/Al2O3catalystswerepreparedbytheconventionalimpregnationmethod,andthephasestructuresandsurfaceacidityofAl2O3supportswereadjustedbycalciningthecommercialγ-Al2O3atdifferenttemperatures(600–1200C).COmethanationreactionwascarriedoutinthetemperaturerangeof300–600Catdifferentweighthourlyspacevelocities(WHSV=30000and120000mL·g-1h-1)andpressures(0.1and3.0MPa).ItwasfoundthathighcalcinationtemperaturenotonlyledtothegrowthinNiparticlesize,butalsoweakenedtheinteractionbetweenNinanoparticlesandAl2O3supportsduetotherapiddecreaseofthespecificsurfaceareaandacidityofAl2O3supports.Interestingly,NicatalystssupportedonAl2O3calcinedat1200C(Ni/Al2O3-1200)exhibitedthebestcatalyticactivityforCOmethanationunderdifferentreactionconditions.LifetimereactiontestsalsoindicatedthatNi/Al2O3-1200wasthemostactiveandstablecatalystcomparedwiththeotherthreecatalysts,whosesupportswerecalcinedatlowertemperatures(600,800and1000C).ThesefindingswouldthereforebehelpfultodevelopNi/Al2O3methanationcatalystforSNGproduction.

  • 标签: Ni catalyst ALUMINA CO METHANATION synthetic
  • 简介:Treatmentof4-amino-3-(1-aryl-5-methyl-1,2,3-triazol-4-yl)-5-mercapto-1,2,4-triazoles/2-amino-5-(1-aryl-5-methyl-1,2,3-triazole-4-yl)-1,3,4-thiadiazoleswithbenzaldehyde,acetoneandω-bromoacetophenonewastestedandcompared.ThetitlecompoundsSchiffbases,amides,imidazolo[2,1-b]-1,3,4-thiadiazolesand7H-s-triazolo[3,4-b]-1,3,4-thiadiazineshavebeenconfirmedbyelementalanalyses,^1HNMR,IRandMSspectra.AllthecompoundshavealsobeenscreenedfortheirantibacterialactivitiesagainstB.subtilis,S.aureusandE.coli.

  • 标签: 合成 抗菌活性 4-氨基-3-(1-芳基-5-甲基-1 2 3-三唑-4-基)-1 3 4-噻重氮 衍生物
  • 简介:The2Dplanegasflowunderheating(withnonentityboundarycondition)hasbeendiscussedbytheanalyticalapproachinthispaper.Theapproximateanalyticalsolutionshavebeenobtainedfortheflowpassingvariouskindsofheatsources.Solutionsdemonstratethethermaldisplacementphenomenaarestronglydependontheheatingintensity.

  • 标签: 热流体流 热位移 解析解
  • 简介:DigitaldecayspectroscopyofactinideisotopesatthegasfilledseparatorSHANSAlloverthechartofnuclides,theregiontothe“north-east”of208Pb,withZ≥84andN=128~130,hoststheshortest-livedαradioactivities,withhalf-livesintherangeofnanosecondstomicroseconds.Synthesisanddetectionofneutron-deficientisotopesabovethoriuminthisregionarechallengingduetotheirlowproductioncrosssectionsandshorthalf-lives.

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  • 简介:ThephotodegradationreactionrateofCHCl3inTiO2particulatesuspensionwasimperovedsignificantlybyHCl-treatment.TheeffectofHCl-treatmentonthephotocatalyticactivityofTiO2wasstrdiedinaPECcellbyusingIntensity-ModulatedPhotocurrentSpectroscopy(IMPS).ThemagntudeofphotocurrentresponseandthecharacteristicfrequenciesoftheupperandlowersemicirclesinthecomplexplaneofIMPSresponsewereanalyzed,andtheccathodicandanodicreactionprocessesofphotogeneratedholesandelectronswerediscussed.Theincreasesinthecathodicandanodicphotocurrentresponseandinthetimeconstantsofbothcathodicandanodicreactionprocessesofphotogeneratedholesandelectronswerediscussed.TheincreasesinthecathodicandanodicphotocurrentresponseandinthetimeconstantsofbothcathodicandanodicreactionprocessesindicatethatHCl-treatmentleadstotheimprovementofthephotocatalyticactivityofTiO2andachangeofthephotocatalytickineticmechanism.

  • 标签: TIO2 IMPS 二氧化钛晶体 三氯甲烷 化学处理 催化剂
  • 简介:AconstructiveproofisgivenfortheinversionformulaforzonalfunctionsonSL(2,R).AconcretelyconstructedsequenceofzonalfunctionsareprovedtosatisfytheinversionformulaobtaAnedbyHarish-Chandraforcompactsupportedinfinitelydifferentiablezonalfunctfons.Makinguseofthepropertyofthissequencesomehowsimilartothatofapproximationkernels,theauthorndeducethattheinversionformulaistrueforcontinuouszonalfunctiotmon8L(2,R)somecondition.Theclassicalresultcanbeviewedasacorollaryoftheresultshere.

  • 标签: 线性函数 倒置公式 近似值 数学分析 证明方法
  • 简介:Depositionoftwo-dimensional(2D)MoS2materialsonthetaperedfiberallowsvariousphotonicapplicationsincludingsaturableabsorbersandfour-wavemixing.Ethanolcatalyticdeposition(ECD)ofMoS2ontheopticaltaperedfiberwasproposedanddemonstratedinthiswork.Differentfromtheconventionalopticaldrivendepositionusingwaterororganicsolvent,theECDmethodutilizedthehighvolatilityoftheethanolsolvent,whichsignificantlyincreasedthemovementspeedoftheMoS2nanosheetsandthusboostedthedepositionrateandreducedtheminimumpowerthresholdtodrivethedeposition.WebelievetheECDmethodshouldbeabletobeappliedtoothersimilar2Dmaterialssuchasothertypesoftransitionmetalchalcogenides.

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  • 简介:Theneutralgaspressurenearplasmaordivertorplatesisveryimportantfortheplasma-wallinteraction,whichdeterminetheoperationmodeofdivertomandconfinementperformancesofplasmaintokamaks.Thecommercialionizationgaugedoesnotworkinstrongmagneticfieldandnoisyenviromentencounteredintokamaks.Themeasuringerromofpressurecommercialionizationareverylargebythegaugemountedonthepumpingsystemorthroughalongpipetothevacuumvessel.Anewionizationgauge,

  • 标签: HL-2A 等离子体 偏滤器 中性气体压强规 诊断控制
  • 简介:Impurity,whichisinducedbytheinteractionbetweenplasmaandthefirstwallsuchaslimiter,isoneofthekeyissuesimpactedthequalityoftokamakplasma.Itisalsothesourceoftheradiationandcoldelectronintokamak,andcanhaveasignificantinfluenceonthebalanceofplasmaenergyandparticleaswellastheprofilesofdensity,temperatureandcurrent.Thesteadystateoperationandtransportfeatureoftokamakplasmaareaffectedbyimpuritytoo.

  • 标签: HL-2A 杂质线 辐射测量 等离子体 温度控制