简介:Amild,regioselective1,3-dipolarcycloadditionprotocolforthepreparationofphenylselenomethylisoxazolinesthroughsubstitutedallylphenylselenidesandnitrileoxideswasreported.
简介:Anovelcomplex,[Cu2(phen)(sal)(Hsal)2]n(1),wassynthesizedandstructurallycharacterized.Thebasicdimericunitsareholdbysalligandsandextendedinto1-Dnetwork.Thecarboxylategrougsofsalicylatescoordinatetothecentralioninthreedifferentcoordinationmodes:chelating,bridgingandbridging-chelating.Inthecaseofbridging-chelatingofthecarboxylategroupofthesalicylate,allthreeoxygenatomsofsalicylatearebidentatelycoordinatedtocopperion,namely,μ4-η^3bindingmode.
简介:Thefollowingdocumentationisanevaluationofthetwo-dimensionalMadelungconstantfortheNaClstructure.TheinfiniteseriesforthestructureisformultedasThefirsttermintheformulaconvergesto41n2.TheseriesafterK=2inthesecondtermisputtogetherwiththethirdtermandaconstant-4/2isleft.ThecombinationofthethirdtermandtheseriesafterK=2inthesecondtermisassumedtobe8Sn.TheconvergingseriesSncanbesolvedonacomputer.Thesevensignificantfiguresofthetwo-dimensionalMadelungconstantfortheNaClstructureisthendeterminedas1.615558.
简介:Three—layerback—propagationneuralnetworkswereusedforprocessingtheinformationprovidedbytheultravioletspectraoffive—componentmixtures,affectingthesimultaneousdeterminationofthecomponentswithsatisfactoryresults.
简介:Anovelcomplex,(H3O)2[Ni(2,6-pydc)2]·2H2Owassynthesizedinanaqueoussolutionandcharacterizedbymeansofsingle-crystalX-raydiffraction,elementalanalysesandIRspectra.TheX-raystructuralanalysisrevealedthatthenovelcompoundformsthree-dimensional(3D)networksbybothπ-πstackingandhydrogen-bondinginteractions.Thecrystaldataforthecomplexarea=13.853(3)nm,b=9.6892(19)nm,c=13.732(3)nm,α=90.00°,β=115.52(3)°,Y=90.00°,Z=3,R,=0.0786,wR2=0.1522.
简介:Poly(vinylidenefluoride)(PVDF)/multi-walledcarbonnanotube(MWCNT)nanocompositeswerepreparedbymeansofultrasonicdispersionmethod.X-raydiffraction(XRD)resultsindicatethatincorporatingMWCNTsintoPVDFcausedtheformationofβphase.Athermalannealingat130°Cconfirmedthattheβphasewasstableinthenanocomposites.Differentialscanningcalorimetry(DSC)resultsindicatethatthemeltingtemperatureslightlyincreasedwhiletheheatoffusionmarkedlydecreasedwithincreasingMWCNTcontent.ThetensilestrengthandmodulusofPVDFwereimprovedbyloadingtheMWCNTs.Thescanningelectronmicroscopy(SEM)observationsshowedthatMWCNTswereuniformlydispersedinthePVDFmatrixandaninterfacialadhesionbetweenMWCNTandPVDFwasachieved,whichwasresponsiblefortheenhancementinthetensilestrengthandmodulusofPVDF.
简介:Polyamide/acrylonitrile-butadiene-styrenecopolymer(PA/ABS)blendshavedrawnconsiderableattentionfrombothacademiaandindustryfortheirimportantapplicationsinautomotiveandelectronicareas.DuetopoormiscibilityofPAandABS,developinganeffectivecompatibilizationstrategyhasbeenanurgentchallengetoachieveprominentmechanicalproperties.Inthisstudy,wecreateasetofmechanicallyenhancedPA6/ABSblendsusingtwomulti-monomermelt-graftedcompatibilizers,SEBSg-(MAH-co-St)andABS-g-(MAH-co-St).Thedisperseddomainsizeissignificantlydecreasedandmeanwhiletheunique“softshell-encapsulating-hardcore”structuresforminthepresenceofcompatibilizers.Theoptimummechanicalperformancesmanifestanincreaseof36%intensilestrengthandanincreaseof1300%inimpactstrength,comparedwiththeneatPA6/ABSbinaryblend.
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简介:Inthisworkamulti-objectivequantitativestructure-propertyrelationship(QSPR)analysisapproachwasreportedbasedonthestudyonthreepartitionpropertiesof50aromaticsulfur-containingcarboxylates.Heremulti-objectives(properties)weretakenasavectorforQSPRmodeling.Thequantitativecorrelationsforpartitionpropertiesweredevelopedusingage-neticalgorithm-basedvariable-selectionapproachwithquantumdescriptors,derivedfromAM1-basedcalculations.WiththeQSPRmodels,theaqueoussolubmty,octanol/waterpartitioncoefficientsandreversed-phaseHPLCcapacityfactorsofsulfur-contalningcompoundswereestimatedandpredicted.UsingGA-basedmultivariatelinearregressionwithcross-vali-dationprocedure,asetofthemostpromisingdescriptorswasselegtedfromapoolof28quantumchemicalsemi-empiricalde-scriptors,inclodingstericandelectronictypes,tointegrallybuildQSPRmodels.Theselectedmoleculardescriptorsinclud-edthenetchargesoncarboxylgroup(Qoc),the2ndpowerofnetehnrgesonnitrogenatoms(QN^2),thenetatomicchargeonthesulfuratoms(Qs),thevanderWaalsvolumeofmolecule(V),themostpositivenetatomicchargeonhydrogenatoms(QH)andthemeasureofpolarityandpolarizability(π),whichweremainfactorsaffectingthedistributionprocessesofthecompoundsunderstudy.ThestatisticallybestQSPRmodelsofsixdescriptorsweresimultaneouslyobtainedbyGA-basedlinearregressionanalysis.WiththeselecteddescriptorsandtheQSPRequations,mechanismsofpartitionactionoftheSulfur-containingcarboxylateswereabletobeinvestigatedandinter-preted.
简介:Inthiswork,acidfunctionalizedmulti-wallcarbonnanotubes(MWCNTs)weremodifiedwithimidazolium-basedionicliquids.Theselectiveoxidationofvariousalcoholswithhydrogenperoxidecatalyzedby[PZnMo_2W_9O_(39)]~(5-),ZnPOM,supportedonionicliquids-modifiedwithMWCNTs,MWCNTAPIB,isreported.Thiscatalyst[ZnPOM@APIB-MWCNT],wascharacterizedbyX-raydiffraction,scanningelectronmicroscopy(SEM)andFT-IRspectroscopicmethods.Thisheterogeneouscatalystexhibitedhighstabilityandreusabilityintheoxidationreactionwithoutlossofitscatalyticperformance.
简介:Thenovelcomplex[K(18-C-6)]2[Cd(mnt)2][18-C-6-18-crown-6,nmt=1,2-dicyanoethene-1,2-dithiolate,C2S2-(CN)2^2-]wassynthesizedandcharacterizedbyelementalanalysis,IRspectrumandX-raydiffractionanalysis.Thecomplexdisplaystwo-dimensionalnetworkstructureof[K(18-C-6)]complexsegmentsand[Cd(nmt)2]complexsegmentbridgedbyS-K-S,S-K-NandN-K-Ninteractionsbetweenadjacent[K(18-C-6)]and[Cd(mnt)2]units.
简介:Thecopper(Ⅱ)complex[Cu3(nta)2(azpy)2(H2O2)]·6H2O(nta=nitrilotriacetate,azpy=4,4′-azobispyridine)hasbeensynthesizedandcharacterized.TheX-rayanalysisrevealsthattherearetwokindsofcopper(Ⅱ)coordinationenvironments.Cu(1)hasadistortedsquareplanesymmetryandCu(2)hasadistortedoctahedralsymmetry.Cu(1)islinkedtoCu(2)throughntaandboundtoCu(1C)byazpy,andCu(2)islinkedtoCu(2A)throughazpy,whichextendstotwo-dimensionalnetworkwithlargerhombus1.2nm×1.7nm.
简介:Theopen-frameworkironphosphateFe2^111Fe1.5^11(PO4)3washydrothermallysynthesizedandcharacterizedbyelementalanalysis,IR,EPR,XPSandsinglecrystalX-raydiffractionanalysis.Thetitlecompoundcrystallizedinthetriclinic,spacegroupP-↑1witha=0.64724(4)nm,b=0.79651(6)nm,c=0.94229(5)nm,α=104.447(2)°,β=108.919(4)°,γ=101.741(4)°,V=0.42302(5)nm^3,Z=1andR1(wR2)=0.0307(0.0793).CrystaldatawerecollectedonaRigakuR-AXISRAPIDIPdiffractometerwithMoKα(λ=0.071073nm)at293(2)Kintherangeof2.43°
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.