简介：Let'stakeHasaninfinite–dimensionalHilbertspaceandK(H)bethesetofallcompactoperatorsonH.UsingSpectraltheoremforcompactself–adjointoperators,weprovetheHyers–UlamstabilityofJensen*-derivationsfromK(H)intoK(H).

简介：对于Rn中充分光滑的凸体,通过欧式单位球面上的迷向测度,刻画了在T∈SL（n）下Mp（TK）和M＊p（TK）的最小值问题.同时也得到了Mp（K）M＊p（K）取得最小值的条件.

简介：Inordertodeepentheunderstandingoftherelationshipbetweenfundamentalproperties（including:microstructureandcomposition）andphotocatalyticperformance,fourbismuthatecompounds,including:LiBiO3,NaBiO3,KBiO3,andAgBiO3,areregardedasresearchexamplesinthepresentwork,becausetheyhaveparticularcrystalstructuresandsimilarcompositions.Usingdensityfunctionaltheorycalculations,theirstructural,electronic,andopticalpropertiesareinvestigatedandcomparedsystematically.Firstofall,thecalculatedresultsofcrystalstructuresandopticalpropertiesareinagreementwithavailablepublishedexperimentaldata.Basedonthecalculatedresults,itisfoundthatthetunneledorlayeredmicro-structuralpropertiesleadtothestrongerinteractionbetweenbismuthandoxygen,andtheweakerinteractionbetweenalkaline-earthmetaland[BiO6]octahedron,resultinginthefeatureofmulti-bandgapsinthecasesofLiBiO3,NaBiO3,andKBiO3.ThisconclusionissupportedbythecaseofAgBiO3,inwhichthefeatureofmulti-bandgapsdisappears,duetothestrongerinteractionbetweenthenoblemetaland[BiO6]octahedron.Thesepropertieshavesignificantadvantagesinthephotocatalyticperformance:absorbinglowenergyphotons,rapidlytransferringenergycarriers.Furthermore,thefeaturesofelectronicstructuresofbismuthatecompoundsarewellreflectedbytheabsorptionspectra,whichcouldbeconfirmedbyexperimentalmeasurementsinpractice.Combinedwiththecalculatedresults,itcouldbeconsideredthatthecrystalstructuresandcompositionsofthephotocatalystdeterminetheelectronicstructuresandopticalproperties,andsubsequentlydeterminethecorrespondingphotocatalyticperformance.Thus,anovelBi-basedphotocatalystdrivenbyvisible-lightcouldbedesignedbyutilizingspecificcompositionstoformfavorableelectronicstructuresorspecificmicro-structurestoformabeneficialchannelforenergycarriers.

简介：K-promotediron/carbonnanotubescomposite(i.e.,FeK-OX)waspreparedbyaredoxreactionbetweencarbonnanotubesandK_2FeO_4followedbythermaltreatmentsonapurposeastheFischer–Tropschcatalystforthedirectconversionofsyngastolowerolefins.ItscatalyticbehaviorswerecomparedwiththoseoftheothertwoFe-IMandFeK-IMcatalystspreparedbyimpregnationmethodfollowedbythermaltreatments.ThenovelFeK-OXcompositecatalystisfoundtoexhibithigherhydrocarbonselectivity,lowerolefinsselectivityandchaingrowthprobabilityaswellasbetterstability.ThecatalyststructureperformancerelationshiphasbeenestablishedusingmultipletechniquesincludingXRD,Raman,TEMandEDSelementalmapping.Inaddition,effectsofadditionalpotassiumintotheFeK-OXcompositecatalystontheFTOperformancewerealsoinvestigatedanddiscussed.Additionalpotassiumpromotersfurtherendowthecatalystswithhigheryieldoflowerolefins.Theseresultsdemonstratedthattheintroductionmethodofpromotersandironspeciesplaysacrucialroleinthedesignandfabricationofhighlyactive,selectiveandstableiron-basedcompositecatalystsfortheFTOreaction.

简介：ThegatedielectricthicknessdecreasesdramaticallywiththecontinuousscalingofMOSdevices,whichhasseriousconsequencesontheleakagecurrentandthepowerconsumptionoftheSiO2-basedMOSdevices.Hafniumdioxide(HfO2),asakindofhigh-kmaterial,arerecognizedasalternativestoSiO2forfutureadvancedgatedevicesandspaceapplications[1].Radiation-inducedeffectsonconventionalSiO2dielectricshavebeeninvestigated.Now,anenormousamountofeffortwasrequiredtoadaptthenewhigh-ksystemsforradiationhardapplication.

简介：

简介：采用UMP2/6-311＋G（3df）方法研究了一系列化合物M_（n＋1）F_n（n=1,2;M=Na,K）体系的几何构型及非线性光学性质（NLO）.结果表明：这些体系均为超价化合物,均拥有较大的第一超极化率（β_0）.尤其是Na_3F_2体系中结构2c的β_0值为29.16×10~（-49）C~3·m~3·J~（-2）,是已知超价化合物Li_3F_2的2c结构的β_0值2.22×10~（-49）C~3·m~3·J~（-2）的13.1倍.