简介:APt-MoO3/Ccatalyst,aimedtoeliminatetheharmfuleffectofsulfurdioxide(SCb)ontheperformanceofPtnanoparticles(NPs)forcatalysisofoxygenreductionreaction(ORR)inprotonexchangemembranefuelcells(PEMFC),isdevelopedandcharacterizedbyTEM,XRDandXPS.TheresultsrevealthatPt-MoO3/Ccatalystexhibitsnotonlyahighercatalyticactivity,butalsoabetterSO2poisoningresistanceandabetterrecoveryperformancethanthecommercialPt/Ccatalystdoes.
简介:Extractionofthein-mediumpropertiesofstrangeparticlesfromheavy-ioncollisionsisverycomplicated,sincehenucleardensityvariesintheevolutionofnucleus-nucleuscollisions.Toavoidtheuncertaintiesofthebaryonensitiesduringthestageofstrangeparticleproduction,onecaninvestigateproton-nucleuscollisionswheretheucleardensityisdefinitearoundthesaturationdensity.DynamicsofstrangeparticlesproducedintheprotoninduceduclearthereactionsnearthethresholdenergieshasbeeninvestigatedwithintheLanzhouquantumoleculardynamics(LQMD)transportmodel.Thein-mediummodificationsonparticleproductionindensenuclearmatterareconsideredthroughthecorrectionstotheelementarycrosssectionsviatheeffectivemassandhemean-fieldpotentials[1].
简介:Nanowireshaveattractedmoreandmoreinterestinrecentyearsduetotheiruniquepropertiescomparedtobulkmaterials[1].Thequitedifferentpropertiespossessedbynanowiresaremainlycausedbytheirhighsurface-tovolumeratio[2].Behaviorsofnanowiresunderirradiationconditionshavealsoattractedintensiveattentionintheseyears[3??5].Ithasbeenproposedthatnanowiresmayberadiationresistancebecausetheirlargesurface-to-volumeratio,andmeanwhilethesurfacearetheperfectsinksfordefectscreatedintheradiationprocess[3].
简介:Sweetsorghum,theworld'sfifthmostimportantcerealafterrice,corn,wheatandbarley,isaveryattractivesourceforbiomassproduction.Thisrawmaterialcomplementssugarcaneproductionandisemergingastheidealfeedforanimalsandfortheproductionofthefirst-generationofbiofuels,suchasethanolandvalue-addedchemicals.Atpresent,mostofthestudiesaboutsweetsorghumfocusonutilization(suchasethanolproduction),andthestudyofsugeraccumulationinstemarerarely.
简介:Duringthepastyear,biophysicsgroupatInstituteofModernPhysics(IMP)obtainedlotsofachievementsintheresearchofheavy-ionmutationbreedingandproductionchainofsweetsorghum.Infundamentalresearchfield,amutantpopulationofArabidopsisthalianainducedbycarbonionbeamradiationwasestablishedinM2generation.Thetotalmutationratewas4.77%.Amutantmarked197#,whichhadfrostbite-like,palegreen,wrinkledandunevenleavesanddisplayedloosebractsandlatematuration,wasobtainedandreportedforthefirsttime.Generoughmappingresultsdemonstratedthatthereweretwomutationsitesinthe1stand4thchromosomeof197#mutant,indicatingheavyionradiationmightinducemorecomplicatedmutationsbeyondourcurrentrecognition.Thewholegenomeresequencingofthismutantisstillinprogress.Inaddition,high-yieldstrainsofmicrobeswhichhavepotentialvalueforcommercialapplication,suchasCorynebacteriumglutamicumandLacbobacillusthermophiles,werescreenedusingheavy-ionmutationtechnique.
简介:CuFe2O4network,preparedviatheelectrostaticspraydepositiontechnique,withhighreversiblecapacityandlongcyclelifetimeforlithiumionbatteryanodematerialhasbeenreported.Thereversiblecapacitycanbefurtherenhancedbycoatinghighelectronicconductivepolypyrrole(PPy).Atthecurrentdensityof100mA·g-1.Li/CuFe2O4electrodedeliversareversiblecapacityof842.9mAh·g-1whilethereversiblecapacityofLi/PPy-coatedCuFe2O4electrodeincreasesupto1106.7mAh-g’.Ahighcapacityof640.7mAhg"1fortheLi/PPy-coatedCuFe2O4electrodeismaintainedincontrastof398.9mAh·g-1forCuFe2O4electrodeafter60cycles,whichdemonstratesgoodelectrochemicalperformanceofthecompositeduetotheincreaseofelectronicconductivity.Theelectrochemicalimpedancespectroscopy(EIS)furtherrevealsthattheLi/PPy-coatedCuFe2O4electrodehasalowerchargetransferresistancethantheLi/CuFe2C>4electrode.
简介:Rhodium-andironphosphate-basedcatalystsarebyfarthemostpromisingcatalystsforoxy-brominationofmethane(OBM)reaction.However,mostliteraturereportedeitherRh-orFePO4-basedcatalysts,andtheresultswererarelystudiedinauniformenvironmentalcondition.Inthisreport,comparativestudywasconductedonsilica-andsiliconcarbide-supportedrhodiumandironphosphatecatalystswiththemainfocusesonstabilityperformanceandcokedeposition.ThecatalyticresultsdemonstratedthatthestabilityofbothRh-andFePO4-basedcatalystswasgreatlyinfluencedbythesupportsused,andsiliconcarbide-supportedcatalystsshowedmuchbetteranti-cokingabilityascomparedwithsilica-supportedones.Temperature-programmedoxidationovertheusedcatalystsfurtherindicatedthatthecokeformationmechanismswerecompletelydifferentbetweensilica-supportedrhodiumandironphosphatecatalysts.WhilecokesmightbecausedbycondensationofCH2Br2oversupportedironphosphate,methanedecompositionmightbethereasonforcokeformationoversilica-supportedrhodiumcatalyst.ThesefindingsmightpavethewayfordesigninghighlyefficientandstablecatalystsoftheOBMreaction.
简介:Duetotheiruniqueadvantagesinphysicsandbiology,heavyionbeams,withhighmutationrateandwidemutationspectrum,havebeenwidelyusedinplantbreedingasanovelandefficientphysicalmutagen.Inthiswork,Arabidopsisthaliana(197#),whichdisplayeddecreasedfertility,wasinducedbycarbonionbeamsacceleratedbytheHeavyIonResearchFacilityinLanzhou(HIRFL).InordertodeterminethediscrepanciesbetweenWTandmutantplants,aseriesofdevelopmentindexeswereanalyzedduringthereproductivegrowthstage.
简介:Muscovitemicasheetswithathicknessof12mwereirradiatedbyswiftheavyionsKrandBifromHeavyIonResearchFacilityinLanzhou(HIRFL).Theuencesrangefrom11010to11012ions/cm2.Theelectronicenergyloss(dE/dx)eincreasesfrom5.9to31.5keV/nm.ThevibrationalmodicationsinirradiatedmicawereinvestigatedbyFourier-transforminfraredspectroscopyandthelatenttrackswereobservedbytransmissionelectronmicroscope(TEM).Theinfraredspectrumshowsthatmotionsfromallatomtypesinthemuscovitemicastructurecouldbefoundinmodesforallvibrations.AsshowninFig.1,theintensityofallvibrationalmodesinmica,includingtheOHstretchmotionat3621cm??1,decreasedwiththeincreasing(dE/dx)e.Thesimilartendencyisfoundinsamplesirradiatedbyswiftheavyionswithincreasingionuence.Itisindicatedthatdefectsandstructuralmodicationsgeneratedduringswiftheavyionirradiation,andmoredefectsareintroducedbyirradiationwithhigherionuence.
简介:Inthispaper,weareconcernedwiththeglobalexistenceandconvergenceratesofthesmoothsolutionsforthecompressiblemagnetohydrodynamicequationswithoutheatconductivity,whichisahyperbolic-parabolicsystem.TheglobalsolutionsareobtainedbycombiningthelocalexistenceandaprioriestimatesifH3-normoftheinitialperturbationaroundaconstantstatesissmallenoughanditsL1-normisbounded.Aprioridecay-intimeestimatesonthepressure,velocityandmagneticfieldareusedtogettheuniformboundofentropy.Moreover,theoptimalconvergenceratesarealsoobtained.
简介:采用HF/DFT的混合泛函PBE0和UPBE0优化了配合物[Os(PH3)2(CN)2(N^N)](其中N^N=2,2′-吡啶)的基态和激发态结构.在基态和激发态结构的基础上,利用含时密度泛函理论(TD-DFT)方法,结合极化连续介质(PCM)模型分别计算了它在二氯甲烷(1)、甲醇(2)、气态(3)和乙腈(4)溶液中的吸收和发射光谱.研究结果表明:优化得到的几何结构参数和相应的实验值符合得非常好.在极性较大的溶剂(2和4)中Os—P(1)和Os—C(1)键较长,Os—N(3)键较短,溶剂的极性会影响配合物的电子云分布.配合物在1-4溶剂中的最低能吸收和发射均来自分子轨道68→71的激发,该激发被指认为[d(Os)+π(CN)+π(N^N)→π*(N^N)]的跃迁具有混合的MLCT/LLCT特征.配合物在1-4溶剂中的最低能吸收和发射分别在471,410,488和445nm以及598,536,634和545nm,表明随着溶剂极性的逐渐增大(3〈1〈4〈2),最低能吸收和发射发生明显的蓝移.这显示出通过改变溶剂极性可以调节配合物的发光颜色.
简介:Two-dimensional(2D)materialshaveattractedgreatresearchinterestsduetotheiruniqueproperties.2DMoS2,unlikeitsbulkformwhichwidelyusedassolidlubricantandcatalyst,isofbrilliantapplicationprospectinnanoelectronicsandoptoelectrnics.Theelectronicdevicesworkinkindsofradiationenvironment.Toevaluatetheionradiationeffectsonmaterialpropertiesandstabilityofdevice,theswiftheavyionradiationeffectonsingle-layerMoS2wasstudiedinthiswork[1??2].