简介:Researchesonorganizationandstructureincomplexsystemsareacademicandindustrialfrontsinmodernsciences.Thoughmanytheoriesaretentativelyproposedtoanalyzecomplexsystems,westilllackarigoroustheoryonthem.Complexsystemspossessvariousdegreesoffreedom,whichmeansthattheyshouldexhibitallkindsofstructures.However,complexsystemsoftenshowsimilarpatternsandstructures.Thenthequestionariseswhysuchsimilarstructuresappearinallkindsofcomplexsystems.Thepaperoutlinesatheoryonfreedomdegreecompressionandtheexistenceofhierarchicalself-organizationforallcomplexsystemsisfound.Itisfreedomdegreecompressionandhierarchicalself-organizationthatareresponsiblefortheexistenceofthesesimilarpatternsorstructuresobservedinthecomplexsystems.
简介:Anewmacrocycliccompoundhasbeensynthesizedbycondensationofpyridine-1-oxide-2,6-dialdehydewithdiethylenetria-mine.Theself-assemlybehaviourswerestudiedbyX-raydiffraction.Theresultsshowthattheself-assemblywerecontrolledbyintermolecularhydrogenbondsandπ-πstackingeffects.
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简介:Thispaperreports,forthefirsttime,thatArchaerhodopsin-4(AR4)couldbereconstitutedintophospholipidliposomesbyself-assembly.AR4isanewmembraneproteinisolatedfromhalobacteriaH.sp.xz515inasaltlakeofTibet,China.Thisisabacteriorhodopsin(bR)likeprotein,functionasalight-drivenprotonpump.ExperimentalmeasurementsverifiedthatsimilartobR,ARnotonlyremainsitsbiologicalactivityinpmteoliposome,butalsokeepsapreferredorientationinself-assembly.
简介:Itiswellknownthatelectrochemicaloxidationofanilinedissolvedinelectrolytesolutionsisaveryusefulmethodforpreparingpolyanilinefilmsonelectrodes’.However,itisverydifficultforthismethodtoprepareauniformmonolayerpolymersincelocalnucleationandgrowthofpolyme...
简介:Hereinwedemonstratetheconstructionofthreetypesofparallelgoldnanorod(AuNR)clustersusingaDNAorigamirod(DOR)asthetemplate.BasedontheprecisecontroloverthepositionofcapturestrandsonDOR,numberandorientationoftheAuNRclusterscanbewellengineered,asevidencedbybiologicaltransmissionelectronmicroscope(TEM).Importantly,theAuNRclustersexhibitchiropticalresponseswhicharestronglyaffectedbythenumberofAuNRonrod-likeDNAorigami.
简介:Polystyrene(PS)fiberswithcore-shellstructureswerefabricatedbycoaxialelectrostaticspinning,[10_TD$IF]inwhichthereareliquidepoxyorcuringagentasthecoreandPSastheshell.Scanningelectronmicroscopy(SEM),Fouriertransforminfrared(FTIR)spectraandopticalmicroscopewereutilizedforcharacteringthemorphologyandcompositionofthefibers.Compositecoatingsembeddedwiththehealant-loadedcoreshellfibershavebeenpreparedandtheself-healingofthescratchonthecoatingshasbeenrevealed.
简介:Anovelacrylateinimer,2-(2-chloroacetyloxy)ethylacrylate,waspreparedbythereactionof2-hydroxyethylacrylatewithchloroacetylchlorideinthepresenceoftriethylamine.Theself-condensingvinyllivingradicalpolymerizationoftheinimerwasstudiedandthehyperbranchedmacromoleculescontainingesterlinkagesontheirbackbonewereprepared.Allthepolymerizationproductswerecharacterizedby1HNMR.Thepolymerizationdegreeandthebranchingparameterwerecalculatedbasedonthe1HNMRspectra.Ithasbeenshownthatthisinimerexhibitsaverydistinctivepolymerizationbehavior.Similartostep-growthpolymerization,thepolymerizationdegreeoftheproductsformedincreasedexponentiallyduringtheearlystageofthepolymerization,andthentheincreasingratesloweddown.However,theinimerremainedpresentthroughoutthepolymerizationconsistentwithconventionalfreeradicalpolymerization.Also,ifmuchlongerpolymerizationtimewasused,thepolymerizationsystemwouldbecomegelduetothecrosslinkingreactionderivedfromradical-radicalrecombination.Asaresultoftheunequalreactivityof-CH2Cland>CHCl,analmostlinearproductwasobtainedatamolarratioofbipytoinimer=0.05,whilearelativelyhighratioofbipytoinimer1favoredtheformationofthebranchedstructure.Themacromoleculesformedatahighratioofbipytoinimer1exhibitedanexcellentsolubilityinorganicsolventssuchasacetone.
简介:Mercaptopropyltrimethoxysilane(MPTS)bearingmercaptogroupswasusedtoformself-assemblymonolayers(SAMs)onglasssubstratesbysolutionextraction.SEM,XRDandrubbingtestanalysisillustratedthattheAgfilmontheSAMs-modifiedglasswasmoredurablethanthatonthecommonly-modifiedglassandthatthecrystallinityofAgfilmontheSAMs-modifiedglasswasidenticalwiththoseoftheAgfilmonthecommonly-modifiedglassandpureAg.
简介:Fourcoumarinderivatives(4a―4d)withdifferentalkoxychainsweresynthesized.Itwasfoundthatcompound4dshowedabettergelationabilitythantheothercompounds,forexample,itcouldself-assembleintoorganogelsinvariousorganicfluidsviaultrasoundtreatmentorheating-coolingprocess,whereascompound4ccouldonlygelinafewmixedsolventsandcompounds4a,4bcouldnotformorganogel.TheresultsfromfluorescentandFT-IRspectraindicatethatπ-πinteractionhadaneffectontheformationoftheorganogelsofcompound4dbesidesH-bondingandvanderWaalsinteraction,whichwerethedrivingforcesfortheself-assemblingofcompound4cingelstate.Thegelofcompound4dintoluenecouldemitstrongfluorescenceunderUVirradiationandthe[2+2]cyc-lo-additionwassuggestedby1HNMRandfluorescencespectroscopy.Thislight-sensitiveorganogelmightfindapplicationinopticalmaterials.
简介:Thenanomaterialsoftenexhibitveryinterestingelectrical,optical,magnetic,andchemicalproperties,whichcannotbeachievedbytheirbulkcounterparts[1-7].Thedevelopmentofuniformnanometersizedparticleshasbeenintensivelypursuedbecauseoftheirtechnologicalandfundamentalscientificimportance[8-15].Itissignificantthatnanostructuredmaterialscanbecontrollablyassembledintotherequiredgeometryontosubstrates,becomingthebasisofthenextgenerationofcomponentsanddevices[16-31].Thedevelopmentofnewmethodsandstrategiesfororganizingthenanoparticlebasicbuildingblocksintothedesiredstructuresisrequired.Superlatticesmadefromthesebuildingblocksgiveustheopportunitytostudynotonlythepropertiesoftheindividualbuildingblocks,butalsocollectiveeffects.Thesuperparamagneticironoxidenanocrystals(NCs)havebeenusedinthefieldsofbio-medicine,ferrofluids,refrigerationsystem,catalysis,particularlyinmagneticresonanceimaging,tissueengineering,anddrugdeliveryapplications[32-42].
简介:在一封初步的信(四面体Lett。2010,51,188),我们报导了二个新基于一种肺结核特效药的四倍的结合氢的主题,这是,二monopodal(1a和1b)和五dipodal(2a,2b和3a3c)从在烃的dipodal主题的超分子的聚合物和泡的芳香的一种肺结核特效药衍生物,和形成。在这份报纸,我们在场有他们在水的媒介的自我装配的行为上的一个重音的这些结合氢的主题的性质上的一幅完整的图画。SEM,AFM,TEM并且荧光灯显微图显示所有dipodal混合物也在极的甲醇和水甲醇(多达50%水)形成泡混合物。控制实验证明1b不在一样的媒介形成泡。到dipodal混合物的溶液的1b的增加禁止后者形成泡的能力。在高集中,3b和3c另外gelate分离溶剂,包括的烃,酉旨,甲醇,和甲醇水混合。集中依赖者SEM调查表明3b和3c的泡熔化形成胶化和3c罐头de总数的胶化reversibly形成泡。
简介:Electroactiveself-assembledmonolayers(SAMs)containingviologeugroupareformedthroughtheadsorptionofthiol-functionalizedviologencompoundCH3(CH2)9V2+(CH2)8SH,whereV2+isN,N’-diaIkylbipyridinium(i.e.aviologengroup),ontogoldelectrodesfrommethanol/watersolutionanditselectrochemicalbehaviorisinvestigatedbyAcvoltammetryandsquarewavevoltam-metry,whichhavethehighsensitivityagainstbackgroundcharging.TheviologenSAMformedisasub-monolayerandthenormalpotentialscorrespondingtothetwosuccessiveone-electrontransferprocessesoftheactivecenters(viologen)are-360mVand-750mV(vs.Ag/AgCl)in0.1mol/Lphosphatebuffersolutions(pH6.96)respectively,andthestandardelectrontransferrateconstantis9.0s-1TheelectrochemicalbehaviorofthisSAMinvarioussolutionshasbeenpreliminarilydiscussed.
简介:Effectsofself-coilingoforganicmoleculesonintramolecularexciplexformationofcompoundI,inwhichthecarbazolechromophoreandterephthalicacidmethylesteracceptorgrouparelinkedbyone(CH2)10chain,andthedecreaseofthefluorescenceintensitiesofcompoundsⅡ,Ⅲ,andⅣ,inwhichthecarbazolechromophoreand3,5-dinitrobenzoateareconnectedbyonealiphaticchainof(CH2)10(Ⅱ),(CH2)12(Ⅲ),or(CH2)4(Ⅳ),havebeenstudiedinthedioxane(DX)-H2Obinarysystem.Theresultsshowthatself-coilingoforganicmoleculesinDX-H2OfacilitatesintramolecularexciplexformationofIandinducesthedecreaseoffluorescenceintensitiesofⅡ,bacauseoftheproximityeffectbroughtaboutbyselfcoilingoforganicmoleculesunderhydrophobic-lipophilicinteraction(HLI)betweentheexcitedcarbazolechromophoreandtheacceptor.SincethesimilareffectsareobservedevenwhentheconcentrationoftheprobesarelessthantheirCAgCs(criticalaggregateconcentrations)intheDX-H2Omixturewiththesameφvalues,formationoftheintermolecularexciplexhasbeenexcluded.Theeffectsarefoundtobestronglydependedonφvalues,indicationthattheyaremainlydrivenbyHLI.Thepropertiesoftheacceptorscanalsoaffecttheintramolecularexciplexformation.Withterephthalicacidmethylestermoietyastheacceptor,thecarbazolechromophoreexhibitsthefluorescencespectraoftheexciplex,whilewith3,5-dinitrobenzoatemoietyastheacceptor,onlythefluorescencespectraofexcitedcarbazolylchromophoreareobserved.
简介:Quartzcrystalmicrobalance(QCM)andcyclicvoltammetry(CV)wereusedtocharacterizethemonolayerofcytochromec(Cytc),whichwasadsorbedongoldfilmmodifiedwithalkanethiolmixedmonolayer.AdirectcomparisonofproteinsurfacecoveragescalculatedfromQCMandcyclicvoltammetricmeasurementsillustratesthattheratiooftheelectroactiveCytctothetotalsurface-confinedCytcis34%,whichsuggeststhattheorientationisamainfactoraffectingtheelectroactivityofCytc.Moreover,surfaceplasmonresonance(SPR)measurementcombinedwithCV'insitu'wasusedtoinvestigatetheconformationalchangeofCytcintheredoxprocess.Besides,Aunanoparticles(AuNPs)wereadsorbedonthesurfaceofCytc.TheresultindicatesthatAuNPspromoteelectrontransferbetweenCytcandthegoldelectrode,andSPRresultsuggestsAuNPsenhanceSPRsignal.
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.