简介:Twocalix[4]arenederivativescontaining1,2,3-triazolemoietyweresynthesizedviaK2CO3-catalyzed1,3-dipolarcycloadditionreactionbetweencalix[4]arene-basedazideandactivemethylenecompoundsingoodyields.Thestructuresofthetwocompoundssynthesizedhereinwerefullyconfirmedby1HNMR,,13CNMR,andMS(ESI).Thethermalanalysisshowedthatthemasslossesofthesynthesizedcompounds4and5containing1,2,3-triazolegroupsaresimilartoeachother.
简介:Twocystine-bearing1,3-bridgedcalix[4]areneswereusedasthecoatingsofthequartzcrystalmicrobalance(QCM)withgoldelectrodes.Thetwocalix[4]arenederivativeswereself-assembledontothegoldelectrodesurfacebythecovalentattachmentbetweenthedi-sulfurandgold.Thecompoundofcystine-bearingbi-phenylalanine1,3-bridgedcalix[4]arene(CPC)withlongeralkylchainhadbetterself-assembledcapacityontothefreshsurfacesofgoldelectrodethanthatofcystine-bearing1,3-bridgedcalix[4]arene(CC)withcomparablyshorteralkylchain.ThemodifiedQCMsensorswereusedtorecognizethebutylamineisomersingas.TheresultsshowedthattheQCMcoatedwithbothcompoundshadpreferentialaffinityton-butylamine,theni-butylamine,t-butylamineintherangeoflowconcentrations,indicatingthatintherecognitionprocess,thesterichindranceeffectplayedanimportantrolewhenformingcomplexwithguestmolecules.Whentheconcentrationsoftheanalyteswereincreased,thepolarityandthemagnetismofthebutylaminebecamedeterminativefactors.Thereversibilitywasimprovedgreatlyandtheequilibriumtimewasmuchshorterontheself-assembledfilmthanonthefilmobtainedbydroppingcoating.
简介:On △I=4 Bifurcation PhenomenaOn△I=4BifurcationPhenomena¥ZhangJingye;YangSunandMikeGuidryTheexperiments-bythenew7--raydetector...
简介:Anewsyntheticapproachto1,4,6-tri-O-benzylmyo-inositolwasdescribedonthebasisoftheregioselectivebenzylationof1,2-O-isopropylidene-4,6-di-O-benzylmyo-inositol,subsequentacidhydrolysis,phosphorylationwithtetrabenazylpyrophosphateandappropriatedeprotec-tion.
简介:Asimplemethodisappliedtocalculatingtheisotopeshifts(ISs)on5S1/2→4D3/2,5/2transitionsof87,88Sr+.FirstwehavecalculatedtheISsoflowertransitionsonaseriesofalkali-likesystemssuchasB2+,Ca+andBa+,whichareinagreementwithotherworks.ThentheISson5S1/2→4D3/2,5/2transitionsof87,88Sr+,whichareusefultostudytheSr+opticalfrequencystandard,areevaluated.
简介:Emissionquenchingof[Ru(bpy)2(4,4’-dcbpy)](PF6)2(1)bybenzenamine,4-[2-[5-[4-[4-dimethylamino]phenyl]-4,5-di-hydro-1-phenyl-1H-pyrazol-3-yl]-ethenyl]-N,N-dimetyl(2)or1,5-diphenyl-3-(2-phenothiazine)-2-pyrazoline(3)wasobserved.Measurementsoftheemissiondecayof1beforeandafteradditionof2or3bysinglephotoncountingtechniquecon-finnedtheobservations.Theemissionquenchingof1by2or3wassubmittedtoStern-Volmerequation.Itwascalculatedthatthequenchingrateconstants(kq)are5.5×109(mol/L)-1s-1for2and4.0×109(mol/L)-1s-1for3,respectively.Theseresultsindicatedacharacterofdynamicquenchingprocess.Thesinglet-stateof2or3wasalsoquenchedby1.ThequenchingbehaviorsdidnotconformtotheStern-Volmerequationandinvolvedbothstaticanddynamicquenchingprocesses.Theapparentquenchingrateconstant(kapp)wascalculatedtobe3×109(mol/L)-1fortheinteractionofexcited2with1,and1.2×109(mol/L)-1forthatofexcited3wit
简介:Therearemoreandmorecountriestoakeanefforttothestudiesofvanadiumalloyforfusionapplication.NIFSinJapanhasrecentlydevelopedan80kgheatV4Cr4Tialloy(NIFS-heat2)aftertheproductionofa500kgscaleV4Cr4TiinU.S.severalyearsago.PropertyevaluationofthealloyhasbeenputintoaninternationalcollaborationprogramunderthecoordinationofIEA(InternationalEnergyAgency).SWIPhasjoinedthecollabrationonthehydrogenembrittlementresistanceevaluationofthealloyt.