简介:Ca_3Co_2O_6,Na和Ni的电子结构做了模型被被基于的Camhride连续全部的精力包裹(CASTEP)的量化学药品软件学习,在密度函数理论(DFT)和伪潜力上。优点(Z)的电子传导性,seebeckcoefficient,热传导性和图被计算。精力乐队结构在做semiconductors.Na的模型shoivs由于代理杂质揭示杂质层次的形式p类型半导体的特性,而是做Ni的模型是n-typesemiconductor。计算结果证明做的模型的电的传导性比的高非--做的模型,当Seebeck系数和做的模型的热电导率是比非做的那些低的时。因为大增加,电的电导率,做Na的模型的Z被提高,热电的性质被改进。作为Seebeck系数的大衰落,在另一方面,Ni-的Z做了模型不到的非--做的模型。
简介:Inthiswork,theinfluenceofCO2onthestructuralvariationandcatalyticperformanceofNa2WO4/Mn/SiO2foroxidativecouplingofmethanetoethylenewasinvestigated.ThecatalystwaspreparedbyimpregnationmethodandcharacterizedbyXRD,RamanandXPStechniques.AppropriateamountofCO2inthereactantgasesenhancedtheformationofsurfacetetrahedralNa2WO4speciesandpromotedthemigrationofOinMOx,Na,Wfromthecatalystbulktosurface,whichwerefavorableforoxidativecouplingofmethane.WhenthemolarratioofCH4/O2/CO2was3/1/2,enrichedsurfacetetrahedralNa2WO4speciesandhighsurfaceconcentrationofOinMOx,Na,Wweredetected,andthenhighCH4conversionof33.1%andhighC2H4selectivityof56.2%wereobtained.WithfurtherincreaseofCO2inthereagentgases,thecontentofactivesurfacetetrahedralNa2WO4speciesandsurfaceconcentrationofOinMOx,Na,Wdecreased,whilethatofinactivespecies(MnWO4andMn2O3)increaseddramatically,leadingtolowCH4conversionandlowC2H4selectivity.ItcouldbespeculatedthatNa2WO4crystalwastransformedintoMnWO4crystalwithexcessiveCO2addedunderthereactionconditions.PretreatmentofNa2WO4/Mn/SiO2catalystbymoderateamountofCO2beforeOCMalsopromotedtheformationofNa2WO4species.
简介:用Co2(CO)8与CH3CSNH2反应制得产物Ⅰ,又用Na2Fe(CO)4与Ⅰ反应制得产物Ⅱ(Ⅰ:Co3(μ3-S)(CO)7(CH3CSNH),Ⅱ:Co2Fe(μ3-S)(CO)7(CH3CSNH).通过元素分析。IR、UV、1HNMR、MS表征并用X射线衍射法测得Ⅱ的单晶结构.该簇合物属三斜晶系、PT空间群,晶胞参数:a=0.9203(1),b=1.1296(2),c=1.1425(2)nm;α=116.40°(2),β=101.92°(2),γ=92.58°(1);z=2,V=1.2162nm3,Dc=1.698cm3,μ=21.89cm-1.结构分析表明,Co2FeS构三角锥分子骨架,所有CO均为端基配体,S1为面桥基配体,CH3CSNH为双齿配体,与Co、Fe形成五元环结构.
简介:TheantibacterialeffectofcarryingsilverB2O3-SiO2-Na2Oglassmaterialwasstudiedbymeansofantibacterialring,nephelometery,MICvalue,thinfilmattachmentandmicrocalorimetry,respectively.TheexperimentalresultsoffivekindsofantibacterialtestmethodsarealmostidenticalandcanverifythatcarryingsilverB2O3-SiO2-Na2Oglassmaterialexertsanexcellentantibacterialperformance.Antibacterialringandnephelometeryaresimple,quick,buttheprecisionisrestrictive.MICvalue,thinfilmattachmentmethodandmicrocalorimetrycanquantitativelycomparetheantibacterialeffectsoftheantibacterialglassmaterial.Comparedwiththetraditionalmicrobetestmethods,themicrocalorimetrycananalyzetheinhibitingeffectofthecell'sgrowthandmetabolismontheantibacterialglassmaterialbymonitoringthethermaleffectcontinuouslyandautomatically.
简介:Themonomericcobalt-phosphite-thiolatocomplex[Co(mpt)2{P(OCH3)3}2]BF4(Hmpt=2-mercaptothiazoline)hasbeenpreparedandcharacterizedbyX-raycrystallography.ThecomplexcrystallizesinthemonoclinicspacegroupC2/cwitha=0.8078(5),b=2.6020(18),c=1.2191(7)nm,β=99.38(1)°,V=2.528(3)nm3,andZ=4.Thestructurecomprisesdiscretecations[Co(mpt)2{P(OCH3)3}2.]+andanionsBF4-,inwhichthecobalt(Ⅲ)atomiscoordinatedtotwochelatempt-andtwoas-orientedmonodentateP(OCH3)3ligandsinahighlydistortedoctahedralgeometry.ThemostdistortedanglesareS(2)-Co(1)-S(2a)of162.23(10)°andN(1)-Co(1)-S(2)of71.47(13)°,thelatteriscausedbythegeometricconstraintofthebidentateligandmpt-.CyclicvoltammetryhasbeenusedtostudytheelectrochemicalbehaviorofthetitlecomplexontheRelectrodeinMeCNsolutionwith0.1mol·L-1ofBun4NBF4aselectrolyte.TheresultsindicatethatthetitlecomplexisunstableinMeCN.
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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.