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简介：Takingadvantageofthelargeγ-detectorarrayGammasphereandtherecoilmassseparatorFMA,highspinstatesin117Bawereinvestigatedthroughtherecoil-β-delayedprotondecaytaggingtechniqueviatheheavy-ioninducedfusion-evaporationreaction64Zn(58Ni,2p3n)117Ba,atabeamenergyof305MeV.Promptγraysbelongingto117Bahavebeenidentifiedfurthermore,arotationalbandhasbeenidentifiedforthefirsttimeandpresentedasbandAinFig.1.

简介：合成了氰根桥联配合物Co[Fe(CN)5NO].5H2O,使用元素分析、热重分析、红外光谱、XRD对配合物进行了表征。红外光谱显示金属离子通过氰根桥联即FeII-CN-NiII传递磁相互作用,是属于桥式氰根配体的CN伸缩振动,而粉末XRD衍射图表明此化合物为面心立方体结构(FCC),空间群为Fm3m(225),晶格常数a=10.2856。通过对该配合物的直流变温磁化率和交流磁化率测定表明金属离子通过氰根传递弱反铁磁作用,根据Curie-Weiss定律,拟合数据获得居里常数C=1.55cm3·K/mol,顺磁居里温度θ=-1.87K。

简介：LARED-H程序是一个可用于激光黑腔靶耦合数值模拟研究的二维辐射流体力学程序。黑腔等离子体所形成的复杂流场使单纯的拉格朗日网格在计算中产生严重扭曲，影响计算精度，并导致计算中断。拉氏加网格重分是计算激光黑腔靶耦合常用的算法。对LARED-H程序的积分网格重分方法在网格重构和物理量重映方面作了较大改进，并利用改进后的LARED-H程序模拟了“神光”-Ⅱ和“神光”-Ⅲ条件下的激光空腔靶耦合物理全过程。

简介：BasedupontheHellinger-Reissner(H-R)mixedvariationalprincipleforthree-dimensionalelasticbodies,themodifiedH-Rmixedvariationaltheoremformagnetoelectroelasticbodieswasestablished.Thestate-vectorequationofmagnetoelectroelasticplateswasderivedfromtheproposedtheorembyperformingthevariationaloperations.Tolayatheoreticalbasisofthesemi-analyticalsolutionappliedwiththemagnetoelectroelasticplates,thestate-vectorequationforthediscreteelementinplanewasproposedthroughtheuseoftheproposedprinciple.Finally,itispointedoutthatthemodifiedH-Rmixedvariationalprincipleforpureelastic,singlepiezoelectricorsinglepiezomagneticbodiesarethespecialcasesofthepresentvariationaltheorem.

简介：Poly(azureblueⅡ)(PABⅡ)thinfilmmodifiedelectrodewassuccessfullyassembledonthesurfaceofaglassycarbonelec-tradebymeansofelectrochemicalpolymerization,whichwascarriedoutwithcyclicvoltammetricsweepinginthepotentialrangeof-0.6to+1.3V(vs.SCE)inBritton-Robinsonbuffersolution(pH=9.8)containing1.25x10^-4mol/LazureblueⅡ.TheeffectofpHonthepolymerizationprocessofazureblueⅡandthedeetrochemicalcharacteristicsofthepolymer-modifiedelectrodeswerestudiedindetail.Theexperimentalre-suitsindicatedthattheelectropolymerizatiouofazureblueⅡcouldtakeplaceinbasicorneutralmedia.Thecyclicvoltam-mogramsofpoly(azureblueⅡ)thinfilmmodifiedelectrodeshowedthepresenceoftwocouplesofredoxpeaks.Thefilmmodifiedelectrodeexhibitedpotentandpersistentelectrocataly-sisforoxidationofdihydronicotiamideadeninedinucleotide(NADH)inphosphatebuffermediawithadiminutionoftheoverpotentialofabout410mVandanincreaseinpeakcurrent.ThepresenceofsomedivalentcationsinanelectrolytecangreatlyenhancetheeleetrocotolyficcurrentforoxidationofNADH.TheeleetrocatalyticcurrentincreasedlinearlywithNADHconcentrationfrom1.0×10^-5to8.0×10^-3mol/Linthepresenceof4.0×10^-2mol/LMg^2+cation.Thedetectionlimit(3Sb1/S)WaS5.0×10^-6mol/L,andtherelativestandarddeviationofdeterminationresultswas4.2%forsixsuccessivedeterminationsof5.0×10^-4mol/LNADHinthepresenceofMg^2+cation.

简介：Twofamiliesofcatalysts,basedonPdnanoparticlessupportedonceramicasymmetrictubularaluminamembranes,arestudiesinthedirectsynthesisofH_2O_2.TheyarepreparedbydepositingPdintwoways:(i)reductionwithN_2H_4inanultrasonicbathand(ii)byimpregnation-deposition.Thefirstpreparationleadstolargerparticles,withaveragesizeofaround11nm,whilethesecondpreparationleadstosmallerparticles,withaveragesizearound4nm.Thecatalyticmembranesweretestedasprepared,afterthermaltreatmentinairandafterfurtherpre-reductionwithH_2inmild(100℃)conditions.SampleswerecharacterizedbyTEM,CO-chemisorptionmonitoredbyDRIFTSmethodandTPR,whilecatalytictestshavebeenperformedinasemi-batchrecirculationmembranereactor.Experimentalcatalyticresultswereanalysedusingtwokineticsmodelstoderivethereactionconstantsfortheparallelandconsecutivereactionsofthekineticnetwork.SmallerparticlesofPdshowlowerselectivityduetothehigherrateofparallelcombustion,evenifthebetterdispersionofPdandthushighermetalsurfaceareainthesampleleadtoaproductivityinH_2O_2similarorevenhigherthanthesamplewiththelargerPdparticles.IndependentlyonthepresenceofsmallerorlargerPdnanoparticles,anoxidationtreatmentleadstoasignificantenhancementintheproductivity,althoughthecatalystprogressivelyreducesduringthecatalyticprocess.Theinhibitionoftheparallelcombustionreaction(towater)inducedfromthecalcinationtreatmentremainsafterthein-situreductionoftheoxidizedPdspeciesformedduringthepre-treatment.Thisislikelyduetotheeliminationofdefectsiteswhichdissociativelyactivateoxygen,andtentativelyattributedtoPdsitesabletogivethree-andfour-foldcoordinationofCO.

简介：ThispaperinvestigatestherobuststochasticstabilityandH∞analysisforstochasticsystemswithtime-varyingdelayandMarkovianjump.Byusingthefreeweightingmatrixtechnique,i.e.,He’stechnique,andastochasticLyapunov-Krasovskiifunctional,newdelay-dependentcriteriaintermsoflinearmatrixinequalitiesarederivedforthetherobuststochasticstabilityandtheH∞disturbanceattenuation.Threenumericalexamplesaregiven.Theresultsshowthattheproposedmethodisefficientandmuchlessconservativethantheexistingresultsintheliterature.更多还原

简介：为electrophilic硝代的一个选择、有效的过程用N2O5被描述为一个绿nitrating代理人，是的H沸石在温和条件下面的稳固的酸催化剂和形状控制代理人。

简介：Ionothermalsynthesiswasusedtoprepareanovelaminoacidcontaininghybridzincophosphatemonomer,[Zn(HPO4)(H2PO4)][C6H10N3O2](denotedasZnPO-CJ58).Theinorganicframeworkof[Zn(HPO4)(H2PO4)]·[C6H10N3O2]consistsof4-memberedringsformedbyZnO3OHisandPO2(OH)2tetrahedra.TheHPO4andaminoacidmoietieshangontheZncenter.Suchaframeworkisstabilizedbyextensivemultipointhydrogenbondsinvolvingthephosphateunitsandhistidinemoleculestoformapseudo-3Dsupramolecularstructure.ItisnoteworthythatZnPO-CJ58isthefirstzincphosphateclusterwithaminoacidactingastheligand.Itexhibitsphotoluminescenceexcitedatawavelengthof220nm.Interestingly,ZnPO-CJ58cantransformintoalayeredstructure(C6H10N3O2)Zn2·(HPO4)(PO4)·H2O(ZnPO-CJ36)throughfurtherreactingwithwaterorzincacetatedihydrateinwaterat85℃for1h.Thisworkwillbehelpfulforthesynthesisofcrystallineinorganic-organichybridmaterialswithbiofunctionalmolecules.

简介：利用水热法首次合成了具有两种配位环境Cd原子的新型杂多蓝化合物[NH3（CH2）2NH3]5[Cd（H2O）][CdMo12^vO30（HPO4）6（H2PO4）2]·5H2O．通过元素分析、ICP、TG和X射线单晶衍射确定了其组成，使用IR和EPR进行了结构表征．通过N2吸附脱附测定了比表面积和孔径，为催化研究提供了基础数据．结果表明：该晶体为三斜晶系，P-1，空间群；晶胞参数a=1．2002（2）nm，b=1．4651（3）nm，c=2．1192（4）nm，V=3．5642（12）nm^3，p=83．01（3）°，Z=2，F（000）=2932，R1=0．0300，wR2=0．0716．

简介：The2-Dheteronuclearcoordinationpolymer{[Ag4Fe2(SCN)12(H2O)2][(inaH)2(H2O)2]}n(1)(inaHistheabbreviationofprotonatedisonicotinicacid)withchemicalformulaC24H20Ag4Fe2N14O8S12hasbeensynthesizedandcharacterizedbysinglecrystalX-raydiffraction,elementalanalysisandIRspectroscopy.TheAgES2ringsconnecttwokindsofoctahedralgeometriesofFe(Ⅲ)ions,[Fe(NCS)6]^3-and[Fe(H2O)E(NCS)4]^-unitswithbridgingthiocyanateionsleadingto2-D[Ag4Fe2(SCN)12(H2O)2]^2-anionframework.Fourkindsofringsincludingtheunprecedentedthirty-twomemberedAg4Fe4(SCN)8ringssharecomersoredgesinthe2-Danionlayerstructure.AllthiocyanatescoordinatetothemetalionsaccordingtotheHSABprinciplewithNatomsbindingtotheFe(Ⅲ)ionsandwithSatomsbindingtoAg(I)ions.Pronoatedinacationsstabilizethelayerstructureascounterionsandhydrogenbondswereformedwithinthepronoatedinacationsdimerandbetweenthedimersandthelatticewaters.Crystaldata:Mr=1560.44,triclinic,P-↑1,a=0.76082(1)nm,b=0.9234nm,c=1.85611(4)nm,α=103.0170(10)°,β=93.7780(10)°,γ=97.4080(10)°,V=1.25385(3)nm^3,Z=1,μ(MoKα)=2.650mm^-1,Dc=2.067g·cm^-3,F(000)=758,R1=0.0412,wR2=0.1003.

简介：ThispaperproposesanadaptivejointsourceandchannelcodingschemeforH.264videomulticastoverwirelessLANwhichtakesintoaccounttheusertopologychangesandvaryingchannelconditionsofmultipleusers,anddynamicallyallocatesavailablebandwidthbetweensourcecodingandchannelcoding,withthegoaltooptimizetheoverallsystemperformance.Inparticular,sourceresilienceanderrorcorrectionareconsideredjointlyintheschemetoachievetheoptimalperformance.Andachannelestimationalgorithmbasedontheaveragepacketlossrateandthevarianceofpacketlossrateisproposedalso.Twooverallperformancecriteriaforvideomulticastareinvestigatedandexperimentalresultsarepresentedtoshowtheimprovementobtainedbythescheme.

简介：Arylhalidesareakindofextremelyvaluablecompoundsusedintransition-metal-catalyzedcouplingreactions,aswellasimportantstructuremotifsinmanynaturalproductsandmanufactureddrugs[1,2].Theclassicalapproachforpreparationofhaloarenesiselectrophilicaromaticsubstitution(EAS)usingvarioushalogenatingreagentsoroxidativehalogenationswithhalogenatingreagentgeneratedinsitufromhalidesandoxidants,suchasperoxide,oxygenandmeta-cholorperoxybenzoicacid(mCPBA)[3,4].However,harshreactionconditionsarerequiredforhalogenationoflessactivearomatics.orthoMetalationfollowedbyhalogenquenchingisanotherapproachforhalogenationofaromatics[5].However,thereareobviousdrawbacksforthesemethods,suchaslowregioselectivity,harshconditionsandevendangerousprocedures.Therefore,thedevelopmentofanalternativeandpracticalwayremainschallengeinorganicsynthesis.

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简介：Afacileandconvenientsynthesismethodhasbeendevelopedforsubstitutedquinoxalinesand2H-benzo[b][1,4]oxazinesfromthereactionsofα-bromoketoneswithbenzene-1,2-diamineand2-aminophenol,respectively,whichwerecatalyzedbytetrabutylammoniumbromide(TBAB)inaqueousbasicmedia.