简介:HeteroatomM-ZSM-12zeolites(M=B,Al,Ge,Ga,Fe)arehydrothermallysynthesizedanditisprovedthattheheteroatomMisinvolvedintheframeworkofsynthesizedmolecularsievesbymeansofXRD,IRspectra.TheresultsofadsorptionanddiffusionexperimentsindicatethattheheteroatomMmodifiestheporevolume,specificsurfacearea,andthechannelofZSM-12molecularsieves.
简介:利用电介质的平均能带模型计算了PrBa2Cu3O7的化学键参数,得到Cu(1)-O键的人价性为0.41,Cu(2)-O键的平均共价性为0.28,应用由共价性和要化率定义的化学环境因子计算了^57Fe在PrBa2Cu3O7中的Mossbauer同质异能位移,确定了^57Fe在PrBa2Cu3O7中的价态和占位情况。
简介:Theoptimalconditionsforthecomplexationreactionofmeso-tetra(3-methoxy-4-hy-droxyphenyl)porphineT(3-M-4HP)Pwithplatinumandrhodiumarepresented.Beer’sLawisobeyedwhentheconcentrationofrhodiumisintherangeof0.45-1.15μg/25mL.Themolarabsorptivityofrhodiumwasfoundtobe1.99×106L·mol-1·cm-1at460nm.ThevalueofεPtwasfoundtobe6.28×105L·mol-1·cm-1bylinearregressionmethod.TheKcoefficientmethodandcompensatingcoefficientwereusedtodetermineplatinumandrhodiumsimultaneoulywithoutremovalormaskingoftheinterferentsinthesample.Theresultsforthedeterminationofplatinumandrhodiuminthemixedsolutionofplatinumandrhodiumaresatisfactory.
简介:Thetitlecomplex[NH_3CH_2CH(NH_2)CH_3]_2[M(Ⅵ)O_2(OC_6H_4O)_2](M=Mo_(0.6)W_(0.4))wassynthesizedviaasimplesolution-phasechemicalroute.ThedeterminationofsinglecrystalX-raydiffractionrevealedthatthetitlecompoundiscrystallizedinamonoclinicsystemwithP2(1)/nspacegroup,a=1.0913(10)nm,b=1.0442(10)nm,c=1.8842(19)nm,α=90°,β=96.530(17)°,γ=90°,Z=4,andV=2.133(4)nm3.Themononuclearanionicunit[M(Ⅵ)O2(OC6H4O)2]2-displayschiralpseudo-octahedral[MO_6]coordinationgeometryandislinkedbychiralcationsviahydrogenbondandπ…πstackinginteraction.Thetransmissionelectronmicroscopyimagesshowthatthetitlecomplexiscomprisedofnano-particleswithdiametersrangingfrom20to50nm.TheNMRstudyshowsthe1Hdownfieldchemicalshiftsof[NH_3CHaHbCH(NH_2)CH_3]+cationsinthetitlecomplexwhenitismixedwithadenosine-triphosphate(ATP),andthechemicalshiftdifferencebetweenHaandHbisincreasedgreatly,andmostofthecatecholateligandsdissociatefromthecentralmetalatoms.TheDNAcleavageactivityexperimentrevealsthatDNAcleavagepromotedbythetitlecomplexislowerthanthatbyNa_2MoO_4whichpossessesantitumorpro-perty,buthigherthanthatbyNa_2WO_4.
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:Bytheadditionalreactionofbinuclearcompounds(Me4N)2M2S4(TDT)2(M=Mo,W;H2TDT=H2CH3C6H3S2)withmononuclearcuprouscomplex,twonewM-Cu-SclustersMo2Cu2S4(TDT)2-(PPh3)2·CH3CH2OH(1)andW2Cu2S4(TDT)2(PPh3)2·0.5CH3CH2OH-0.5H2O(2)havebeenpreparedandcharacterizedbyIR,UV-Vis,31PNMRspectroscopy,cyclicvoltammetryandsinglecrystalX-raystructureanalysis.BothcompoundscrystallizeinspacegroupP21/nwithlatticeparametersa=1.0956(3),b=2.2072(3),c=2.4340(3)nm,β=100.36(2)°,V=5.790(3)nm3andZ=4for1anda=1.0965(9),b=2.2135(3),c=2.4317(4)nm,β=99.63(8)°,V=5.819(8)nm3andZ=4for2.Bothmolecularstructurescontainacubane-likeclustercore[M2Cu2S4](M=Mo,W)andtheirskeletonsarealmostthesameexceptforMatoms.Thesyntheses,structuresandspectrumcharacterizationsofthesetwoclustersarediscussed.Thethird-ordernonlinearoptical(NLO)propertyofthetwoclusterswasstudiedbythetechniqueofforwarddegeneratefour
简介:Europium(Ⅲ)-dopedYF3ispreparedbyahydrothermalprocessat200℃.X-raydiffraction(XRD)patternidentifiestheformationofYF3phasewithoutdetectableimpurity.Environmentscanningelectronmicroscopy(ESEM)imageshowstheevensizedistributionofthesampleswithcubicmorphology.TheexcitationandemissionspectraoftherareearthionsdopedYF3areinvestigatedbyfluorescencespectrophotometer.Theexcitationspectrumfor591nmemissionhasseveralexcitationbandsat320,365,386,397and467nm,andthemainpeakvaluewas397nm.TypicalEu3+emissionpeaksat591nm(5D0→7F1)and612nm(5D0→7F2)areobservedwhenexcitedby397nm,andthestrongestemissionis591nm,demonstratingthattherareearthionsoccupythecentrosymmetricalsitesinYF3.
简介:[Co3(1,2-S2C6H4)3(PPh3)3][CoBr3(DMF)].sol(1,sol=CHCl3,O(C2H5)2,H2O)wasobtainedfromthereactionofCoBr(PPh3)3withNa2(S2C6H4)inchloroform.TheCo3coreinthecationof1exhibitsametal-metalbondedisoscelestriangle,inwhichthetwolongerCo-CobondsarebothbridgedbyS2C6H4ligandsontwosidesofthetriangleplanerespectively,whilethebottomshortCo-CobondisbridgedbythethirdbidentateS2C6H4ligand.Aseriesofpolynu-clearcobaltclustercompoundswithphosphine,thiolateand/orsulphurligandswerepreparedbylowoxidationstateCo+withthiolatesinorganicsolvents.Thesetri-,tetra-,hexa-,heptanuclearclustercompounds1-8withvarioustypesofcrystalstructurescanbeviewedasthecondensedpolynuclearcobaltcomplexesthatthecobaltatomframeworkswithsulphurbridgedwerebuiltthroughthesmalltriangularunitsof[Co3S3nL3](n=1,2)withorwithout[CoL](L=PR3,Br,Cl,5-C5H5)fragments.
简介:Reactionsofthe6-hydroxy-thiopyrano[3,4-c]pyridine-5-carbonitrilederivative1withα-halo-carbonylcompoundsgavetheortho-substitutedintermediates2a-cwhichwereconvertedintofuro[2,3-b]thiopyrano[4,3-d]pyridines3a-cbyfusionofafuranmoietyunderbasicconditions.Furthercyclizationof3a-cledtoafusionofapyrimidinering,yieldingthetetracyclicproducts6,7and8.Inaddition,condensationof6withvariousaromaticaldehydesaffordedthecorrespondingimines9a,b.Mannichreactionof7gaveproducts10a,b.
简介:DrugsSPD-304(6,7-dimethyl-3-{[methyl-(2-{methyl-[1-(3-trifluoromethyl-phenyl)-1H-indol-3-ylmethyl]-amino}-ethyl)-amino]-methyl}-chromen-4-one)andzafirlukastcontainacommonstructuralelementof3-substitutedindolemoietywhichcloselyrelatestoadehydrogenatedreactioncatalyzedbycytochromeP450s(CYPs).ItwasreportedthatthedehydrogenationcanproduceareactiveelectrophilicintermediatewhichcausetoxicitiesandinactivateCYPs.DrugL-745,870(3-{[4-(4-chlorophenyl)piperazin-1-yl]-methyl}-1H-pyrrolo2,3-β-pyridine)mighthavesimilareffectsinceitcontainsthesamestructuralelement.Weusedmoleculardockingapproachcombinedwithmoleculardynamics(MD)simulationtomodelthree-dimensional(3D)complexstructuresofSPD-304,zafirlukastandL-745,870intoCYP3A4,respectively.Theresultsshowthatthesethreedrugscanstablybindintotheactivesiteandthe3-methylenecarbonsofthedrugskeepareasonablereactivedistancefromthehemeiron.ThecomplexstructureofSPD-304-CYP3A4isinagreementwithexperimentaldata.Forzafirlukast,thecalculationresultsindicatethat3-methylenecarbonmightbethedehydrogenationreactionsite.DockingmodelofL-745,870-CYP3A4showsapotentialpossibilityofL-745,870dehydrogenatedbyCYP3A4at3-methylenecarbonwhichisinagreementwithexperimentinvivo.Inaddition,residuesinthephenylalanineclusteraswellasS119andR212playacriticalroleintheligandsbindingbasedonourcalculations.ThedockingmodelscouldprovidesomecluestounderstandthemetabolicmechanismofthedrugsbyCYP3A4.
简介:以化学沉淀法制备单相的铕离子掺杂硼铝酸盐红色荧光粉YAl3(BO3)4:Eu3+,考察了焙烧温度、掺铕量等因素对材料性能的影响,用X射线衍射、扫描电镜、激发光谱和发射光谱对荧光粉的结构、形貌和发光性能进行了表征.以尿素为沉淀剂,900℃焙烧沉淀前驱体可得到单相荧光粉YAl3(BO3)4:Eu3+,反应温度比传统高温固相法降低了300℃;沉淀法制备的荧光粉粒径分布范围小,无团聚现象,粒径约300nm.掺铕量为10%(物质的量比)时发光强度最大.在260nIn的紫外光激发下,Eu3+的5D0→F72的电偶极跃迁最强,发射光为618nm的红光.
简介:ELECTRON TRANSFER BETWEEN Eu3+ AND Ce3+ IN SrMgF4 MATRIXELECTRONTRANSFERBETWEENEu3+ANDCe3+INSrMgF4MATRIX¥YingWU;Ch...