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383 个结果
  • 简介:Fe2O3solwiththeparticlediameterof3-5nmwasflocculatedbytheadditionofSDS,andtheflocculateformedwasredispersedbythefurtheradditionofthatsurfactant.ThusthesurfactantbilayerwasformedonthesurfaceofFe2O3.Theemulsionpolymerizationofstyrene(St)adsolubilizedonthesurfactantadsorbedbilayerwascarriedoutbyinitiatorpotassiumpersulfate(KPS).TheUV-Visandsurfacephotovoltagespectra(SPS)indicatethattheFe2O3particleswereencapsulatedinpolystyrene(PSt)successfully.

  • 标签: FE2O3 nanoparticles Encapsulation Composite MICROSPHERES
  • 简介:Thispaperreportstwolanthanidecomplexesofformula(C9H7)Ln(C8H8)·(THF)2whereLnisProrNd,C9H7isindenyl,andC8H8iscyclooctatetraene(COT).ThecomplexeswerepreparedbythereactionofLnCl3withK(C9H7)andK2(C8H8)inTHF.(C9H7)Pr(C8H8)·(THF)2crystallizesinTHFat-15℃inthemonoclinicspacegroupP21:withunitcelldimensionsa=8.446(0),b=10.083(2),c=13.407(3),β=105.48(1)°,V=1100.43(35)3,Dc=1.52g/cm3andZ=2.ThefinalRvalueis0.033,Rwvalueis0.030,respectively.In(C9H7)Pr(C8H8)·(THF)2afive-memberedringcentroidofC9H7,theC8H8ringcentroidandthetwooxygenatomsfromthetwoTHFmoleculesformadistortedtetrahedralgeometryaroundthemetal.

  • 标签: complexes monoclinic membered C8H8)Ln C8H8)Pr C9H7
  • 简介:8,8′-Dibromo-6,6′,7,7′-tetramethoxy-5,5′-diisopropyl-3,3′-oxydimethylenedinaphtho[2,1-b:2′,1′-d]furan,C32H30Br2O;M.W.=670;triclinic;spacegroupP1;a=8.896(2),b=10.216(1),c=10.423(1)A,α=108.48(1),β=119.36(1),γ=99.26(1);V=723.5A3;Z=1,Dcal.=1.479g.cm-3.MoKα=28.11cm-1,F(000)=326,T=293K.Thestructurewassolvedbydirectmethodandfull-matrixleast-squaresrefinementconvergedatR=0.034for2377observedreflections.Theoxygenatominseven-memberedringexistsinadisorderedarrangement.Bothbisnaphthaleneandoxygen-containingfive-memberedringhaveplanarconformationswithdihedralangle6°,showingmarkedaromaticfeature.

  • 标签: FURAN derivative dibromo-6 6 TRICLINIC membered planar
  • 简介:Thetetranuclearalkyltin(Ⅳ)compounds{[R2Sn(C9H8N3O3)O]SnR3}2[R=n-Bu(1),4-CNC6H4CH2(2),C6H5CH2(3),4-ClC6H4CH2(4)]werepreparedbythereactionofSchiffbaseligandpyruvicacidisonicotinylhydrazonewith(R3Sn)2Ointhecorrespondingmolarratioof1:1.Allcompoundshavebeencharacterizedbyelementalanalysis,IRand^1HNMRspectra.Thecrystalstructureofcompound1wasdeterminedbyX-raysinglecrystaldiffractionalanalysis.Thiscompoundexhibitsadimericstructurecontainingdistannoxaneunitswithtwotypesofthetinatoms.Forthefirsttinatom,itappearstobeseven-coordinatedwithadistortedpentagonalbipyramidgeometry,andtheotherisfive-coordinatedwithadistortedtrigonalbipyramidalgeometry.Themoleculesarepackedintheunitcellintwo-dimensionalnetworkstructurethroughaninteractionbetweentheNatomsofthepyridineandthetinatomsofanadjacentmolecule.

  • 标签: CH IR NMR CNC
  • 简介:采用对称性破损态方法结合密度泛函理论,选用反铁磁双核配合物[Cu2(MMBPT)2Cl4(H2O)2.5](MMBPT=3-甲基-4-对甲基苯基-5-(2-吡啶)-1,2,4-三唑)作为研究对象,通过与实验数据相比较,探讨了不同密度泛函方法与基组对计算铜配合物交换耦合常数的准确度.结果表明,4种混合密度泛函DFT(B3LYP,B3P86,B3PW91和PBE0)的计算结果都能和实验所观察到的值-31cm-1符号一致,但只有B3PW91方法得到的结果和实验结果吻合程度最好,同时采用方法B3PW91方法计算所得的交换耦合常数Jab对基组的依赖性较大.研究表明,2个Cu(Ⅱ)离子之间弱的反铁磁相互作用主要源于单占据分子轨道SOMOs小的能量劈裂.

  • 标签: 1 2 4-三氮唑 双核铜配合物 磁性 密度泛函理论 对称性破损态
  • 简介:ThespinelferritesMnFe2O4nanowiresweresynthesizedbyhydrothermalroute,porousMnFe2O4andnanoparticlesmorphologiesweresynthesizedbysol-gelmethodwitheggwhite.Thestructures,morphologies,magneticpropertiesandadsorptionpropertiesoftheseobtainedferriteswithdifferentmorphologieswerestudiedcontrastively.Resultsshowthattheobtainedsamplesexhibitferromagneticproperties.Thisrealizesconvenientmagneticseparationfromsolutionwhentheyareusedinthetreatmentoforganicdyeswastewater.However,thecontrastivestudiesshowthatthesaturationmagnetizations(Ms)ofMnFe2O4withdifferentmorphologiesaredifferentandtheMsfollowstheorder:Ms(porous)

  • 标签: 多孔结构 吸附性能 磁学性质 纳米粒子 纳米线 MnFe2O4
  • 简介:WiththedecreaseofpHvaluefrom8.45to–1.0,theUV-Visabsorptionandfluorescentspectraof1,2-bis(4-pyridyl)ethylene(BPE)tookonthesamechangingtrendatfourdifferentsuccessivepHstages:8.45―7.20,7.20―5.62,5.62―2.60,and2.60―-1.0,namely,nochange,decrease,increase,anddecreaseagain.Amongthese,inarangeof7.20―5.62,thefluorescencewavelengthblueshiftedfrom418to359nm,buttheUV-Visabsorptionwavelength,incontrast,redshiftedfrom285to298nm.ThefluorescenceintensityofBPEhadadropeventoquenchuponadeclineinthepHvaluefrom2.60to–1.0probablyowingtoitscation-πinteractiontoreducetheπelectronclouddensityofBPE.Twodissociationconstants,pKa1(4.30±0.01)andpKa2(5.65±0.04),wereobtainedbasedonfluorescencedata.ThechangesoffluorescencespectraindicatethatBPEhas'off-on-off'switchbehavior.ThefluorescentspectraofBPEwerenearlyindependentonthepresenceofα-andβ-cyclodextrins.

  • 标签: 乙烯 荧光转换 荧光探针 阳离子交互作用 水解
  • 简介:Thehydrolysisreactionof(±)-2-acetamido-3-hydroxy-1-(4-nitrophenyl)-1-propanone[(±)-1],anintermediateofchloramphenicol,wasstudiedandthreedifferentproductswereobtainedrespectivelyunderdifferentreactionconditions.Theresolutionofhydrolysisproduct(±)-2-amino-3-hydroxy-1-(4-nitrophenyl)-1-propanone[(±)-3]wascarriedout.Aprocessofcrystallization-inducedasymmetrictransformationwasobservedandupto76%oftheopticallypureenantiomerwasobtainedintheresolutionof(±)-3.

  • 标签: Hydrolysis Resolution EPIMERIZATION
  • 简介:TofindoptimalconditionsforexpressingthesolubleformofsFv-2F3andtostudythepurificationandpropertyofitsderivativeSe-sFv-2F3,thepreferredexpressionconditionswereinvestigatedbymeansoforthogonaldesign.Thesecultureconditionsincludedincubationtemperature,inducerconcentration,inductiontimeandcellconcentration.TheevaluationofexpressionwasaccomplishedbytheanalysisofwholecelllysatesandtheyieldofsolublesFv-2F3wascalculatedaccordingtotheanalysisofProfinder(FTI-500,Pharmacia).Thepurificationprocedurewascarriedoutviaatwo-steppurificationprocedureconsistingofion-exchangechromatography,followedbyimmobilizedmetalaffinitychromatography(IMAC).TheantioxidantefficacyofSe-sFv-2F3wasdemonstratedbythedeterminationofthecontentofthemainproductoflipidperoxidation,MDA,theviabilityofcellsandtheactivityofLDH.WeobtainedthepreferredcultureconditionstogrowtheengineeredbacteriaandtheprocedureforpreparingsolublesFv-2F3andconfirmedtheantioxidantefficacyofSe-sFv-2F3.

  • 标签: Se-sFv-2F3 可溶表示 谷胱甘肽过氧化物酶 抗氧化剂
  • 简介:Inthisarticle,nano-scaleAl/Fe2O3compositeswithdifferentmorphologiesweresuccessfullyobtainedbyasimpleelectrospinningtechnique,whichisbasedonasurfactant(polyvinylpyridine,PVP)inamixtureofN,N-dimethylformamide(DMF)and2-propanol.TheelectrospunAl/Fe2O3compositesexhibitedacrystalstructureandphasecompositionbyX-raydiffractionanalysis.ThedifferentmorphologiesoftheAl/Fe2O3compositeswerealsoobservedthroughscanningelectronmicroscopyandtransmissionelectronmicroscopy.Itwasfoundthattherathersimpleelectrospinningmethodusedtopreparethemorphology-controlledAl/Fe2O3compositesmayhavethepotentialforpreparationofpropellants,explosives,andpyrotechnicsinthefuture.

  • 标签: 下线 服务 迁移
  • 简介:MHP(CH3OOH)和EHP(CH3CH2OOH)的电离精力被方法根据在6-311+G*基础的Koopmans定理设置了的光谱学(足)测量和两个Gaussian-2(G2)计算和Hartree-Fock(HF)第一次铺平的HeI光电子决定了。MHP和EHP的PE系列的任务和描述被G2和HF计算也支持。MHP和EHP的第一个电离精力分别地是9.87和9.65eV。在空气的EHP的更高的溶解度被归因于他们的更低的电离精力价值。

  • 标签: 电光子分光光谱 量子计算 甲基过氧化氢 乙基过氧化氢 哈特里-福克法
  • 简介:Asupramolecular1Dferromagneticsystemwasstudiedexperimentallyaswellastheoretically.Hybriddensityfunctionaltheory(DFT)calculationswerebasedontheX-rayanalysis.TheresultsofDFTcalculationsandMcConnellmechanismhavecontributedtotheunderstandingofthefactorsgoverningtheexchangecouplingofmagnetisminthecrystalpacking.Boththeexperimentalevidenceandtheoreticalcalculationindicatethatspindensityin2-iodonitronylnitroxide(INN)radicalsconfirms1Dferromagneticchainwithinter-chainantiferromagneticinteraction.

  • 标签: 反铁磁相互作用 氮氧自由基 密度计算 自旋密度 一维 DFT计算
  • 简介:在Au的鼹鼠比率的5nmAuPdnanoalloy:Pd=32:1被准备,作为reductant把钠柠檬酸盐用作稳定的代理人和NaBH4。AuPdnanoalloy被aptamer修改准备aptamer-AuPd(AptAuPd)为回声散布的探查(RS)5.01250nmol/LHg2+的察觉。AptAuPd-Hg2+aptamer反应答案被膜过滤,并且在filtrate的AptAuPd展出了强壮的催化效果在上慢捏粒子反应在之间NiCl2和NaH2PO2,和NiP粒子在508nm显示出一座RS山峰。当Hg2+集中增加了时,RS紧张减少了。减少的RS紧张对在0.51250nmol/L的范围的Hg2+集中线性。RS试金被用来在真实样品决定Hg2+,与好结果。

  • 标签: 共振散射 痕量汞 适体 检测 催化剂 修饰
  • 简介:HighlyactiveandselectiveCu/SiO2catalystsforhydrogenationofdimethyloxalate(DMO)toethyleneglycol(EG)weresuccessfullypreparedbymeansofaconvenientone-potsyntheticmethodwithtetraethoxysilane(TEOS)asthesourceofsilica.XRD,H2-TPR,SEM,TEM,XRFandN2physisorptionmeasurementswereperformedtocharacterizethetextureandstructureofCu/SiO2catalystswithdifferentcopperloadings.TheactivecomponentswerehighlydispersedonSiO2supports.Furthermore,thecoexistenceofCu0andCu+contributedalottotheexcellentperformanceofCu-TEOScatalysts.TheDMOconversionreached100%andtheEGselectivityreached95%at498Kand2MPawithahighliquidhourlyspacevelocityoverthe27-Cu-TEOScatalystwithanactualcopperloadingof19.0%(massfraction).

  • 标签: CU/SIO2催化剂 草酸二甲酯 TEOS 乙二醇 催化性能 加氢
  • 简介:ThecrystalstructureofN-(2,3,4,6-tetra-O-acetyl-β-D-gly-cosyl)-thiocarbamicbenzoylhydrazine(C22H27N3O9S)wasdeterminedbyX-raydiffractonmethod.Thehexopyranosylringadoptsachairconformation.Alltheringsubstituentsareintheequatorialpositions.Theacetoxyl-methylgroupisinsynclinalconformation.TheSatomisinsynperiplanarconformationwhilethebenzoylhydrazinemoietyisanti-periplanar.Thethiocarbamicmoietyisalmostcompanarwiththebenzoylhydrazinegroup.Therearetwointramolecularhydrogenbondsandoneintermolecularhydrogenbondforeachmoleculeinthecrystalstructure.Themoleculesformanetworkstructurethroughintermolecularhydrogenbonds.

  • 标签: 晶体结构 N-(2 3 4 6-四-间-乙醚基-β-D-糖基)硫氨基甲酸苯甲酰肼 氢键 构象
  • 简介:Inthispaper,athiol-functionalizednanophotocatalystMPTES/TiO_2wasfirstsynthesizedbyone-potmethodusingP123asatemplate.X-raydiffractionconfirmsthecompleteanatasecrystallineofthiol-functionalizedTiO_2,N_2adsorption-desorptionisothermdemonstratedthatthesematerialspossesshighsurfaceareaandmesoporousstructure.TheresultsofXPSshowthatMPTEShasbeensuccessfullypolymerizedinmesoporousstructuredTiO_2.Thephotodegradationofphenanthrene(PHE)wasinvestigatedundervisiblelightirradiation(λ>420nm)toevaluatethephotocatalyticactivityofthesematerials.BasedtheexperimentresultsofGC-Massanalysis,apossiblemechanismwasproposed.

  • 标签: 纳米复合材料 可见光照射 光催化降解 二氧化钛 功能化 多环芳烃
  • 简介:应用量子化学DVXα方法对钌系氰氯络合物进行了系统的理论计算和解析,确定了相应的稳定几何形态和微观电子结构,为合成、应用和深入研究它们的性能提供了重要的理论依据.

  • 标签: 钌系氰氯络合物 电子结构 DVXα方法
  • 简介:STUDIESONTHESYNTHESISANDREACTIONWITHALKOXIDESOF3-OXO-1,2-BENZOISOTHIAZOLINE--ACETAMIDE1,1-DIOXIDESGuoFengZHAO;HuaZbengYANG(I...

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