简介:<正>Foranoddfunctionf(x)definedonlyonafiniteinterval,thispaperdealswiththeexistenceofperiodicsolutionsandthenumberofsimpleperiodicsolutionsofthedifferentialdelayequation(DDE)(?)(t)=-f(x(t-1)).Byuseofthemethodofqualitativeanalysiscombinedwiththeconstructingofspecialsolutionsaseriesofinterestingresultsareobtainedontheseproblems.
简介:Theoneplusone(1+1)modeofhydrosilationreactionofladderlikecis-isotaticpolyallylsilsesquioxane(AllyI-T)andpolyhydrosilsesquioxane(H-T)usingdicyclopentadienylplatinumdichloride(Cp2PtCl2)asthecatalystleadstotheformationofanewpolyorganosiloxane(POS).ThepresenceofnanoscaletubularstructureintheproductPOSwaspreliminarilyprovedbyIR,1H-NMR,differentialscanningcalorimetry(DSC),X-raydiffraction(XRD),gelpermeationchromatography(GPC),atomicforcemicroscopy(AFM)andmolecularsimulation.
简介:Itisknownfromclassicaldifferentialgeometrythatonecanreconstructacurvewith(n-1)prescribedcurvaturefunctions,ifthesefunctionscanbedifferentiatedacertainnumberoftimesintheusualsenseandifthefirst(n-2)functionsarestrictlypositive.ItisestablishedherethatthisresultstillholdsundertheassumptionthatthecurvaturefunctionsbelongtosomeSobolevspaces,byusingthenotionofderivativeinthedistributionalsense.ItisalsoshownthatthemappingwhichassociateswithsuchprescribedcurvaturefunctionsthereconstructedcurveisofclassC∞.
简介:Usingfourβ-cyclodextrinderivatives,2,6-di-O-benzyl-3-O-heptanonyl-β-CD,2,6-di-O-benzyl-3-O-octanonyl-β-CD,2,3-di-O-benzyl-6-O-heptanonyl-β-CD,and2,3-di-O-benzyl-6-O-octanonyl-β-CD,aschiralstationaryphasesofcapillarygaschromatography(CGC),theenantiomersofSharplessepoxideswerewellseparated.Theenantiomerexcessvalues(e.e.%)ofsomechiralSharplessepoxideswerealsodeterminedsuccessfullyusingtheseCDs.
简介:UsingthemethodofGirsanovtransformation,weestablishtheTalagrand'sT2-inequalityfordiffusiononthepathspaceC([0,N],R^d)withrespecttoauniformmetric,withtheconstantindependentofN.ThisimprovestheknownresultsfortheL2-metric.
简介:Afusionbreedermightbeanessentialintermediateapplicationoffusionenergyatearlierterm,sinceithasthepotentialtoprovideplentyofcommercialfissilefuel.Basedonfusionphysicsandtechnologiesavailableatpresentandinthenearfuture,therealisticfusionexperimentalbreeder,FEB-Ewasdesigned.
简介:Thestraininducedcrystallizationbehaviourinpolyimidefrom1,4-bis(3’,4’-dicarboxyphenoxy)benzeneand4,4’-oxydianiline(PEI-E)hasbeeninvestigatedbyWAXD,DSCandFTIR.TheresultsobtainedshowthatcrystallizationinPEI-Edidtakeplacejustaftertensileyielding.Meanwhile,theeffectofstraininducedcrystallizationonthethermomechanicalpropertieswasstudiedbyDMAandTMA,theresultsofwhichindicatethatthecrystallizationandhotstretchinghaveacertaininfluenceonthedynamicmechanicalproperties,suchasweakeningtheβrelaxationanddecreasingtheglasstransitiontemperature.TheTMAresultsconfirmtheshiftingofglasstransitiontemperaturetolowertemperatureregionafterhotstretching.ThisphenomenoncouldbewellexplainedbytheeffectofresidualstressaccordingtoEyring’stheory.
简介:WeprovideconvergenceresultsanderrorestimatesforNewton-likemethodsingeneralizedBanachspaces.TheideaofageneralizednormisusedwhichisdefinedtobeamapfromalinearspaceintoapartiallyorderedBanachspace.Convergenceresultsanderrorestimatesareimprovedcomparedwiththerealnormtheory.
简介:ThewastewaterfromnaphtholAs-EproductionprocesswastreatedwithmacroporouspolymericadsorbentNDA-222.NaphtholAs-Eand2,3-acidinthewastewatercouldberemovedcompletelyandtheTotalOrganicCarbon(TOC)ofthewastewaterwasdecreasedmorethan98%from1655mg/Ltolessthan30mg/L.TheadsorbatescouldbedesorbedcompletelywithNaOHaqueoussolution.
简介:让p是一个奇怪的素数。在我们介绍的这份报纸,二次的线性p鈥揳lgebraQ1由合适改变Q的发电机获得了,在H鈭炩€搑ing系列的范畴的cohomology操作的同类的二次的代数学,并且仔细看在情况p=相似的商在cohomology上导致的地图2,结果是injective。因此,它的目标包含古典亚当斯的E2鈥搕erm光谱顺序作为subalgebra。对的明确的描述在Q上在合理假设下面被给是Koszul代数学。关键词Koszul代数学-代数学的Cohomology-亚当斯光谱顺序先生(2000)题目分类55S10-18G15-55T15
简介:EscherichiacoliL-asparaginasewasmodifiedwithO-car-boxymethylatedchitosanusingglutaraldehydeasacouplingagent.Theresultingcoujugateretainedmorethan50%ofitsoriginalenzymeactivityundertheprotectionofitsnormalsubstrateorproductandshowedmarkedresistancetoproteolysisbytrypsinandchymotrypsin.
简介:Theglassytransitionofthepolyethyleneterephthalate(PET)sampleswhichhavebeensubjectedtosolventinducedcrystallization(SINC)wasinvestigatedbymodulateddifferentialscanningcalorimetry(MDSC)anddensitymeasurement.Thedif-ferentialofheatcapacitysignal,dC_p/dTfromMDSC,wasusedtomonitortheSINCprocess.ItrevealsthattheT_gtemperatureshiftstohighervaluewiththeadvancementofSINC.Whenthetoluene-immersingtimewaslonger(168h),thedetectionofT_gbecomemoredifficult,becausesomesmallerpeaksemergedatthelowertemperaturesandtheseareexplainedasthemovementofsmallsegmentsintheamorphousregion.TheseobservedresultsareduetothemorphologyandstructureintroducedbytheSINCprocess.