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简介：Thesorptionbehaviorandmechanismofanovelchelateresin,diglycolamidicacidresin(DAAR),forSm(lll)wereinvestigated.TheoptimalsorptionconditionofDAARforSm(lll)ispH=6.0inHAc-NaAcmedium.Thestaticallysaturatedsorptioncapacityis190mg/gresinat298K.TheSm(lll)adsorbedonDAARcanbeelutedreaching100%by0.5-2.0mol/LHCIusedaseluant.Theresincanberegeneratedandreusedwithoutapparentdecreaseofsorptioncapacity.Theapparentsorptionrateconstantisk298=1.96×10^-5s^-1.Theapparentactivationenergyis26kJ/mol.ThesorptionbehaviorofDAARforSm(lll)obeystheFreundlichisotherm.Thethermodynamicsorptionparameters,enthalpychangeΔHofDAARforSm(lll)is16.9Kl/mol.ThemolarcoordinationratioofthefunctionalgroupofDAARtoSin(111)is3.ThesorptionmechanismofDAARforSm(lll)wasexaminedbyusingchemicalmethodandIRspectrometry.ThecoordinationbondwasformedbetweenoxygenatomsinthefunctionalgroupofDAARandSin(Ill).

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简介：Cobaltandnickelcomplexes(1a-1dand2a-2d,respectively)supportedby2-imidate-pyridineligandsweresynthesizedandusedfor1,3-butadienepolymerization.ThecomplexeswerecharacterizedbyIRandelementanalysis,andcomplex1awasfurthercharacterizedbysingle-crystalX-raydiffraction.Thesolidstatestructureofcomplex1adisplayedadistortedtetrahedralgeometry.Uponactivationwithethylaluminumsesquichloride(EASC),allthecomplexesshowedhighactivitiestoward1,3-butadienepolymerization.Thecobaltcomplexesproducedpolymerswithhighcis-1,4contentsandhighmolecularweights,whilethenickelcomplexesdisplayedlowcis-1,4selectivityandtheresultingpolymershadlowmolecularweights.Thecatalyticactivitiesofthecomplexeshighlydependedontheligandstructure.Withtheincrementofpolymerizationtemperature,thecis-1,4contentandthemolecularweightoftheresultingpolymerdecreased.

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简介：Inthispaper,anewthin-layerion-exchangeresinphaseanalyticalmethodisintroduced.Itisbasedonthat,thebismuthouscationcanassociatewithiodicanions,soastoformedananioncomplex[BiI4-_]inastrongacidicenvironments.Thisanioncomplexcanalsoexchangeswithaweakeranionsonthesurfaceactivesiteofanionexchangeresin,sothata[R+][Bil4-]solidphasebinaryassociationalsystemisproduced.Owingtothesolidsystemisagreatmanydispersiveparticulates,itcanbepressedtoathin-layerbypresstoolsofthesocalled"thin-layerresinphase"or"resinphase",andusingthissolidassociationsystemspectrophotometryforthedeterminationoftracemetals.Soitcanincreasetheanalyticalsensitivity.Thisassociationsystemexhibitsmaximumabsorbanceat460nm,andobeysBeer'slawovertheconcentrationrange0.0lug/ml-l.20ug/mlofbismuthous(lll),hhasamolarabsorptivityof7.1×l^5[L/mol.cm].itindicatedtheresinphasespectrophotometryisasensitiveanalyticalmethodfortracebismuthous.Itis18timeshigherthanroutineaqueousspectrophotometry.Therelativestandarddeviationsis1.82%(n=6)fortheFfmeasurementsof0.Sug/mlBi(llO.ThedetectionlimitofBismuthous(lll)is1.4XlO~mol/L.ThemethodhasappliedtotheanalysisBi(lll)inenvironmentalwatersamples.

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简介：Thecopolymerizationsofethylenewith10-undecen-1-olhavebeeninvestigatedusingvanadiumprecatalysts,bis(imino)pyrrolylvanadium(III)complexes1-3,2,5-C4H2N(CH=NR)2VCl2(THF)2[R=C6H5(1),2,6-iPr2C6H3(2),C6F5(3)],andtheiminopyrrolylandβ-diketiminateonesforcomparison.Thepolarmonomerwaspretreatedbydiethylaluminiumchloride(presentalsoasthecocatalyst)beforethecopolymerization.ThemonomerreactivityratioswereevaluatedusingtheFineman-Rossmethod.Theligandstructureconsiderablyinfluencedthecatalyticactivityandtolerancetowardsthepolarmonomer,thepolarmonomerincorporationandthemolecularweightsoftheresultantcopolymers.Thebis(imino)pyrrolylvanadiumcomplexesexhibitedpromisingcatalyticperformanceforthecopolymerization,andahighcatalyticactivityupto3.84kg/mmolv·hwithahighcomonomerincorporationof14.0mol%wasachievedbycomplex3undermildconditions.

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