简介:Themononuclearcomplex,[NtCl2(trzCHzCHzCOPh)4]·6H2O(trz=1,2,4-triazole),wassynthesizedanditsstructurewasdeterminedbysinglecrystalX-raydetermination.Itcrystallizesinthemonoclinicsystem,spacegroupP21/c,withlatticepa-rameters:a=0.80391(2)nm,b=1.06215(2)nm,c=2.90133(2)nm,β=94.792(1)°andZ=2.EachnickelatomiscoordinatedbyfourNatomsoftriazolefromfourβ-(1,2,4-IriHole-1-yl)propiophenoneligandsandtwochlorideanionsinarrangementwithoctahedralcoordinationgeometry.Inadditiontothecoordinatingnickelcomplex,therearesixunco-ordinatedwatermolecules.TheNi—Ndistanceis0.24865(8)nmandtheNi—Ndistaneesareintherangeof0.2072(2)to0.2099(2)nm,respectively.Inthesolidstate,theUtiecom-poundformsthreedimensionalnetworkstructurethroughhy-drogenbonds.Theintermolecularhydrogenbondsconnectthe[NiCl2(C2H2N3CH2CH2COPh)4]andH2Omoieties.Thedeepgreencrystalswerealsoexaminedbyelementalanalysis,FT-IRandUVspectra,whichareinagreementwiththestructuralda-ta.
简介:Anewμ3-Otriiron(Ⅲ)complex[Fe3O(OBz)6(CH3OH)3](NO3)(CH3OH)2(HOBZ=benzoicacid)hasbeensynthesized,itsstructurehasbeendeterminedandvariabletemperaturemagneticsusceptilityhasalsobeenmeasured.Inthemolecule,threeironatomsformedanequilateraltrianglewithu3-Oincenter.ThefittingtothemagneticsusceptibilityshowedthatanintramolecularantiferromagneticexchangeinteractionoccurredbetweenironatomswithJ=-25.51cm-1,andaweakerintermolecularantiferromagneticexchangeinteractionoccurredwithzJ’=-2.30cm-1.
简介:采用直接动力学的方法,对多通道反应体系Br+CH3S(O)CH3进行了理论研究.在BH&H-LYP/6-311G(2d,2p)水平下获得了优化几何构型、频率及最小能量路径(MEP),能量信息的进一步确认在MC-QCISD(单点)水平下完成.利用正则变分过渡态理论,结合小曲率隧道效应校正(CVT/SCT)方法计算了该反应的两个可行的反应通道在200K~2000K温度范围内的速率常数.在整个反应区间内,生成HBr的反应通道与生成CHa的反应通道存在着竞争,前者是主反应通道,后者是次反应通道.变分效应和小曲率隧道效应对反应速率常数的计算影响都很小.理论计算得到的两个反应通道的反应速率常数与实验值符合得很好.
简介:Anumberofnaphthalenedonorcompoundsthatpossessanadamantanaminebindingmoietyandan(OCH2CH2)n(nn1,2,3,4,6,8)spacerweresynthesized.Thefluorescencequenchingbetweenthesedonorsubstratesandmono-6-O-p-nitrobenzoyl-β-cyclodextrin(pNBCD)andmono-6-O-m-nitrobenzoyl-β-cyclodextrin(mNBCD)wasstudiedindetail.Itwasfoundthatveryefficientfluorescencequenchingcouldoccurinthesesupramolecularsystems.Thisquenchingwasattributedtothephotoinducedelectrontransferinsidethesupramolecularassemblybetweenthenaphthalenedonorsandcyclodextrinacceptors.DetailedStern-VolmerconstantsweremeasuredandtheywerepartitionedintodynamicStern-Volmerquenchingconstantsandstaticbindingconstants.Itwasdemonstratedthatthebindingconstantsbetweenallthenaphthalenecompoundsandcyclodextrinsarethesameastheypossessthesamebindingsite,i.e.,adamantanamine.
简介:ThecrystalstructureofDi-nitratobis(ethylcaprolactam)uranyl(Ⅱ)UO2[CH2(CH2)4CONC2H5]2(NO3)2wasestablishedbyasingle-crystalX-raydiffractionstudy.Itistriclinie,spacegroupP1,witha=7.171(2),b=8.655(3),c=10.182(5)A,α=78.27(3),β=70.63(3),γ=81.76(3)°,V=581.7(4)A3,Z=l,Dc=1.94g.cm-3.FinalRvalueis0.0218.Theresultrevealsthaturanylioniscoordinatedtosixoxygenatoms,twoofthemarefromtwocarbonylgroupsofethylcaprolactamandtheotherfourarefromtwonitrategroups.
简介:Thesolidaddofthefirstprotonatedzincoborophosphate,(H3O)Zn(H2O)2BP2O8·H2O(1),wassoventothermallysyn-thesizedbythereactionofZn(NO3)2·6H2OandH3BO3withH3PO4inamixedsolvent,andstructurallycharacterizedbysingle-ystalX-raydiffractionanalysis.ItcrystallizesinthehexagonalP6122,a=0.9604(4)nm,c=1.5297(6)nm,V=1.2218(8)nm^3,Dc=2.921g/cm^3,Z=6,F(000)=1080,μ=3.495mm^-1.Thestmchwefeaturesthatthetetrahedra-te-trahedrahdlcesinterconnectedbyoctahedraandstronghydro-gembondinteractionsformathree-dimensionalframework.Theprotonatedwatermoleculesarelocatedatuniquepositions.othercharacterizationsbyIRandthermalanalysisarealsode-scribed.
简介:Throughmeasuringthecoefficientoflinearexpansion,thestructureandpropertiesoftheLi2O-Al2O3-SiO2lowexpansionglassceramicscontainingB2O3arestudiedbyJRandXRD.ItisshoutnthattheIRmethodisefficientinthestudyoftheglass-ceramicsstructure.Thereisa"Boronabnormality"inthesystemwhichhasanimportantinfluenceonthepropertiesoftheglass-ceramics.
简介:Theobjectinthispaperistoconsidertheproblemofexistence,uniqueness,explicilrepresentationof(0,2)-interpolationonthezerosof(1-x2)Pn-1(x)/xwhennisodd,wherePn-1denotesLegendrepolynomialofdegreen-1,andtheproblemofconvergenceofinterpolatorypolynomials.
简介:TheZrO2-Al2O3ceramiccompositeswerepreparedbyappropriatetechniqueswithcommercialZrO2andAl2O3powdersasrawmaterialsandY2O3asstabilizer.TheresultsindicatethatwiththeintroductionofAl2O3intotheZrO2matrixwherethequantityofadditiveY2O3is3.5%(molefraction),thegrowthofZrO2grainsisefficientlyinhibited,whichhelpstheZrO2grainsexistinametastabletetragonalmanner;thushigherstrengthandtoughnessareacquired.Whenthecontentofaluminais20%(massfraction),thebendingstrengthandfracturetoughnessofthecompositesare676.7MPaand10MPa·m1/2respectively,themechanicalbehaviorsareclosetothosepreparedwithZrO2andAl2O3powderssynthesizedthroughwetchemicalapproach.Themechanicalbehaviorsofthecompositesarewellimprovedowingtothedispersiontougheningofaluminagrainsandphasetransformationtougheningofzirconiagrains.
简介:TheantibacterialeffectofcarryingsilverB2O3-SiO2-Na2Oglassmaterialwasstudiedbymeansofantibacterialring,nephelometery,MICvalue,thinfilmattachmentandmicrocalorimetry,respectively.TheexperimentalresultsoffivekindsofantibacterialtestmethodsarealmostidenticalandcanverifythatcarryingsilverB2O3-SiO2-Na2Oglassmaterialexertsanexcellentantibacterialperformance.Antibacterialringandnephelometeryaresimple,quick,buttheprecisionisrestrictive.MICvalue,thinfilmattachmentmethodandmicrocalorimetrycanquantitativelycomparetheantibacterialeffectsoftheantibacterialglassmaterial.Comparedwiththetraditionalmicrobetestmethods,themicrocalorimetrycananalyzetheinhibitingeffectofthecell'sgrowthandmetabolismontheantibacterialglassmaterialbymonitoringthethermaleffectcontinuouslyandautomatically.