简介：Averymildandextremelyefficienthydrolysismethodfortransformationofpolystyrene-b-poly(tert-butylacrylate)(PS-b-PtBA)topolystyrene-b-poly(acrylicacid)(PS-b-PAA)wasdesignedandcarriedoutusingmoreconvenientandinexpensivechlorotrimethylsilane/sodiumiodideasreagents.Thehydrolysisproductcanself-assembleinaqueousmediatogiveregularmicelleswithPSblockformingthecoreandPAL4blockformingthecorona,orintetrahydrofuran(THF)togivereversemicelleswiththehydrophilicblockinthecore.

简介：Thephotophysicalpropertiesofaseriesofsulfonatedmicromolecule(paratoluenesulfonicacid,HPTS)andmacromolecules(linearandcrosslinkedpolystyrene)havebeenstudiedbysteady-statefluorescencespectra.Theresultsindicatethatthegroundsulfonatedringassociationscanforminboththemicromoleculesandthemacromolecules.Thefluorescencespectraofthesulfonatedcrosslinkedcopolymersappearared-shiftwhenthecopolymerschangefromhydrogen-typetosodium-type,andsomenewemissionbandsappearinthelong-wavelengthregion.Theseresultsareexplainedintermsofsynergeticeffectofhydrogenbond,π-πinteractionandcrosslinkingeffect.

简介：聚苯乙烯涂的硅石(SiO2@PS)核心壳有大约290nm的平均直径的合成粒子被准备由在在直径的2050nm的-methacryloxypropyltrimethoxysilanegraftedSiO2nanoparticles的表面上的苯乙烯的situ乳剂聚合。在10wt%PS答案的SiO2@PS暂停的Rheological行为和分散稳定性与未经治疗的SiO2的暂停相比，silane修改了SiO2nanoparticles。暂停未经治疗并且silane修改了展出的SiO2明显砍变瘦。SiO2@PS暂停展览砍比暂停更加小的粘性未经治疗并且silane修改了SiO2在低砍率。传播电子显微镜学证明合成粒子能一致地并且稳定地与另外的暂停相比在PS答案分散，暗示PS壳罐头有效地提高与在答案的PS大分子的粒子相容性。

简介：Inthispaper,blendmembranesfrompolyvinylacetate(PVAc)andblockcopolymerpoly(amide-12-b-ethyleneoxide)(Pebax1074)arepreparedbysolutioncastingandsolventevaporationmethod.Althoughtheyarehomogeneousonamacro-scale,theobservationsfromDSCandSEMindicatemicro-phaseseparationforPVAc/Pebax1074blendmembranes.WiththeincreaseofPebax1074content,gaspermeabilitiesofCO2,H2,N2andCH4allincreasegreatly.PVAc/Pebax1074blendmembraneswithhighPVAccontentareappropriateforCO2/CH4separation.Thetemperaturedependenceofgaspermeabilityisdividedintorubberyregionandglassyregion.Theactivationenergiesofpermeationinrubberyregionaresmallerthanthoseinglassyregion,andtheyalldecreasewithincreasingPebax1074content.ForN2,H2andCH4,theirgaspermeationpropertiesaremainlyinfluencedbythedual-modesorptionandhydrostaticpressureeffect.ButforCO2,itspermeabilityincreaseswiththeincreaseofpressureduetoCO2-inducedplasticizationeffect,whichismoreobviousforPVAc/Pebax1074blendmembraneswithhighPVAccontent.

简介：Polysiloxane-polystyrenecompositelatexeswerepreparedbytwo-stageemulsionpolymerization.Polymerizationofstyreneinswollenpolysiloxanelatexparticleswerestudied.Formationofsimplepolystyreneparticleinthe2nd-stagepolymerizationdependsontheparticlesizeofthelst-stagelatexandthepolymerizationtemperature.Polystyrenedomainsinthevulcanizatesreinforcethesiliconerubberseffectively.

简介：Ethyl-cyanoethylcellulose((E-CE)C)/styrenesolutioncouldformanisotropicsystemwhentheconcentrationwashighenough.The(E-CE)C/polystyrene(PS)multiphasepolymercouldbeobtainedbyradicalpolymerizationofthestyreneinthesolution.The(E-CE)C/PSmultiphasepolymermaintainedboththecrystallinestructureofthe(E-CE)CandtheamorphousstructureofthePS.Inthemultiphasepolymerproducedfromtheisotropicsolution,however,the(E-CE)CformedspherulitesandspreadinthePSamorphousphase.While,inthemultiphasepolymerproducedfromtheanisotropicsolution,the(E-CE)formedcylindericcrystallineaggregates.Moreover,theorderedlamellartexturewasalsoobservedinthemultiphasepolymerproducedfromtheanisotropicsolution.

简介：Theexfoliationdegreeofgraphiteoxideintographeneoxideplaysanimportantroleinthemassiveproductionmethodofreducedgrapheneoxide.Itissignificanttofindasimpleandfeasiblemethodtoanalyzetheexfoliationdegreeofgraphiteoxide.Inthepresentwork,graphiteoxidewassynthesizedbyamodifiedHummersmethod,andthengrapheneoxidecolloidswereobtainedbyexfoliationofgraphiteoxidedispersedinde-ionizedwater.UV-visiblespectroscopywasusedtocharacterizetheabsorptionofthegrapheneoxidecolloids,andtheconcentrationofgrapheneoxidecolloidsindicatedbyabsorptionareaofUV-visiblespectrawasstudied.Resultsshowthatthereisarelativelystablerelationshipbetweenthem,indicatingthatUVvisiblespectroscopyisapotentialmethodforanalyzingtheexfoliationdegreeofgraphiteoxideintographeneoxide.

简介：Theeffectsofanexogenousnitricoxidedonor(sodiumnitroprusside,SNP),aNOscavenger2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxode(PTIO)andcarboxy-PTIOpotassiumsalt(cPTIO)ontheembryogerminationofSorbuspohuashanensiswerestudiedinapetridishtest.SNPat0.5–5mmolL-1increasedgerminationpercentage,meantimetogermination,germinationindexandgerminationenergycomparedwiththecontroltodifferentdegrees.Treatmentwith2mmolL-1SNPimprovedgerminationmostsignificantly;embryogerminationpercentageformothertree1(91.11%)andmothertree2(64.44%)weremuchhigherthanthecontrol.Inaddition,excessiveSNPlevelsdidnotenhanceembryogermination.CombinedtreatmentwithSNPandanNOscavengerdelayedembryogermination.TreatmentwithcPTIOinhibitedembryogermination;germinationpercentagewas42.22%andwaslowerthanthatofthecontrol.TheseresultsshowthatlowconcentrationsofexogenousNOcanenhancetheembryogerminationofS.pohuashanensis,providingasimple,effectivewayforpromotinggerminationofS.pohuashanensis.

简介：

简介：Thediffusionbehaviorofpolystyrenewithnarrowmolecularweightdistributionat20℃in1,4-dioxanewasinvestigatedbythephotoncorrelationspectroscopy.Thecumulantmethodwasemployedfortheanalysisoftheintensity-intensityautocorrelationfunctionmeasuredoverawiderangeofthescatteringvector.ThediffusioncoefficientDwasdeterminedasthefunctionofconcentrationCinthemolecularweightrangeof3.0×104-1.20×106.Inalowconcentrationrange,DwasfoundtobelinearlydependentonC,whichhasbeenfoundforsomeothersystems.ThedependenceofDonmolecularweightatinfinitedilutioncanbewrittenasanempiricalformulaD0=kDM-γM,theexponentγ(0.576±0.01)isingoodagreementwiththeresultofthescalingtheory.

简介：ＰｒｅｐａｒａｔｉｏｎｏｆＰｏｌｙｓｔｙｒｅｎｅＤｏｐｅｄｗｉｔｈＹｔｒｉｕｍＥｔｈｏｘｉｄｅａｎｄＳｔｕｄｙｏｎＴｈｅｉｒＣｏｏｒｄｉｎａｔｉｏｎＳｈｅｎｇＹｕ（生瑜），ＺｈａｎｇＷｅｎｇｏｎｇ（章文贡）（ＩｎｓｔｉｔｕｔｅｏｆＰｏｌｙｍｅｒＳｃ...

简介：

简介：Nitricoxide(NO)isapleiotropicregulator,criticaltonumerousbiologicalprocesses,includingva-sodilatation,neurotransmissionandmacrophage-mediatedimmunity.Thefamilyofnitricoxidesynthases(NOS)comprisesinducibleNOS(iNOS),endothelialNOS(eNOS),andneuronalNOS(nNOS).Interest-ingly,variousstudieshaveshownthatallthreeisoformscanbeinvolvedinpromotingorinhibitingtheetiologyofcancer.NOSactivityhasbeendetectedintumourcellsofvarioushistogeneticoriginsandhasbeenassociatedwithtumourgrade,proliferationrateandexpressionofimportantsignalingcomponentsassociatedwithcancerdevelopmentsuchastheoestrogenreceptor.ItappearsthathighlevelsofNOSexpression(forexample,generatedbyactivatedmacrophages)maybecytostaticorcytotoxicfortumorcells,whereaslowlevelactivitycanhavetheoppositeeffectandpromotetumourgrowth.Paradoxicallytherefore,NO(andrelatedreactivenitrogenspecies)mayhavebothgenotoxicandangiogenicproperties.IncreasedNO-generationinacellmayselectmutantp53cellsandcontributetotumourangiogenesisbyupregulatingVEGF.Inaddition,NOmaymodulatetumourDNArepairmechanismsbyupregulatingp53,poly(ADP-ribose)polymerase(PARP)andtheDNA-dependentproteinkinase(DNA-PK).Anunderstand-ingatthemolecularleveloftheroleofNOincancerwillhaveprofoundtherapeuticimplicationsforthediagnosisandtreatmentofdisease.

简介：Weinvestigatethedynamiccrystallizationprocessesofcolloidalphotoniccrystals,whicharepotentiallyinvaluableforsolvinganumberofexistingandemergingtechnicalproblemsinregardstocontrolledfabricationofcrystals,suchassizenormalization,stabilityimprovement,andaccelerationofsynthesis.Inthispaper,wereportsystematichigh-resolutionopticalobservationofthespontaneouscrystallizationofmonodispersepolystyrene(PS)micro-spheresinaqueoussolutionintoclose-packedarraysinastaticlineopticaltweezers.Theexperimentsdemonstratethatthecrystalstructureismainlyaffectedbytheminimumpotentialenergyofthesystem;however,thecrystallizationdynamicscouldbeaffectedbyvariousmechanical,physical,andgeometricfactors.Thecomplicateddynamictransformationprocessfrom1Dcrystallizationto2Dcrystallizationandthecreationandannihilationofdislocationsanddefectsviacrystalrelaxationareclearlyillustrated.Twomajorcrystalgrowthmodes,theepitaxygrowthpatternandtheinsertedgrowthpattern,havebeenidentifiedtoplayakeyroleinshapingthedynamicsofthe1Dand2Dcrystallizationprocess.Theseobservationsofferinvaluableinsightsforin-depthresearchaboutcolloidalcrystalcrystallization.

简介：

简介：Emulsifier-freeemulsionpolymerizationofstyreneinthepresenceofβ-hydroxypropylacrylatewasstudied.Theemulsifier-freeselfcrosslinkedpolystyrenelatexmicrosphereswasobtained.Monomerconversionishigherthan90%when[St],[β-HPA],[KPS]is2.66,0.228,and5.8×10^-3mol/Lrespectivelyunder80℃for5h.Themono-dispersedlatexparticlediameterandcolloidalparticleconcentrationweregivenasD=0.23um,N=3.13×10^13/cm^3byTEManalyse,Thefactorsofinfluencinglatexstabilitywerediscussed.ThecopolymerwascharacterizedbyIRanddissolutionexperiment.Theapparentactivationenergyofpolymerizationandpolymerizationrateconstantwereobtainedtobe78.7KJ/moland514.4/mol.srespectively.

简介：Thediblockcopolymersintercalatedlayeredsilicatewaspreparedviaameltdispersiontechnique.Thentheeffectofintercalatedhybridasfilleronacrylonitrile-butadiene-styreneresinwascharacterizedbyX-raydiffraction,transmissionelectronmicroscopy,stress-strainmeasurementsinelongation.

简介：OxidemetallurgytechnologyhasbeendevelopedatBaosteelforimprovingtheheataffectedzonetoughnessofsteelplatesforhighheatinputwelding.AfterdeoxidationwithstrongdeoxidizersofMgalloy,thecomplexinclusionscontainingpartsofcompoundsofMgO,Ti2O3,MnO,Al2O3,MnS,CaSandTiNareformed.Thesekindsofinclusionsarebeneficialforpromotingtheformationofintragranularferrite.Aftertwo-electrodevibratoryelectrogasarcweldingwiththeV-typegrooveandahighheatinputof395kJ/cminasinglepass,theformeraustenitegrainisveryfineinsize,withanaveragegrainsizeofonly85μm.Excellentheataffectedzonetoughnessisobtainedforthedevelopedsteelplateswithathicknessupto68mm.

简介：Modifieddiphenyloxideresinwassynthesizedbyco-polymerizationofunsaturatedacidanddiphenyloxidederivants.Andthenmodifiedbismaleimideresinandexpoxidelinearphenolicresinwereaddedintomodifieddiphenyloxideresintoco-polymerizeandmodifyoncemore.Thesystemwasappliedincomposites.Theirpropertieswereinvestigatedandfoundthattheymettherequirementsasaheat-resistingadhesive.

简介：Meltsofleadbismuthgallatecompositionsarehighlycorrosiveandattackoncruciblesofdifferentmaterials.Inthepresentstudy,corrosionbyabaseglass(50PbO-30Bi2O3-20Ga2O3inmolefraction)meltedusingdifferentcruciblesandtheeffectonUV-VISandIRedgeswerestudied.Bymeltingthebaseglassinplatinum/2%rhodium,goldzirconiaandaluminacruciblesshowedlesseffectontheIRedgeandthereforeshiftedtheinfrarededgetolongerwavelength,whereassilicacruciblecontaminatedtheglass,causingaseveredeteriorationintheinfraredandhenceshiftedinfrarededgetomuchshorterwavelength.IntheUV-VISregion,baseglassmeltedinplatinum/2%rhodiumcrucibleshiftedtheedgetothelongestwavelengthwhereassilicacrucibleshiftedtheedgetoshorterwavelength.Thecontaminantsfromgold,zirconiaandaluminacruciblescausedtheUV-VISedgeofthebaseglasstoliebetweenthetwoextremesofPt/2%RhandSiO2crucibles.Theglassesmeltedinabovementionedcrucibleswerealsocharacterizedwithinductivelycoupledplasmaspectroscopy(ICP)analysistomeasurethelevelofcontaminationfromthecrucibles.Dependinguponcrucibleused,thecolorsofglassesobtainedrangedfromredtoyellow.