简介:Duetolowactivationcharacteristics,desirablehigh-temperaturestrength,goodresistancetoradiationdamageandusablefabricationproperties,vanadium(V)alloysareattractivecandidatestructuralmaterialsforfusionreactors[1].Irradiationinducedhardening/embrittlementatlowtemperatureisamajorproblemforthematerialsapplicationinfusionreactor[2].Inthisstudy,H/Heionswithvariousenergieswereusedtoirradiateapurevanadium(V)andaValloy(V-4Ti)toobtainadamageplateaufromsamplesurfacetothedepthof1.5m,asshowninFig.1[3].Thedetailsofirradiationparameters(energies,fluences)forHandHeionsareshowninTable1.NanoindentationwasperformedtoinvestigatethehardeningbehaviorofV-4TialloyandpureVunderirradiation.
简介:AnovelmethodformodelingcellularmaterialsisproposedbasedonMATLABimageprocessingandsynchrotronX-raycomputedtomographyscanningtoobtainanaccuratecalculationresultofaluminumfoambasedonfiniteelementmodel.Themaximumentropyalgorithmisemployedtoobtainthebinarizationimage,andthemedianfilteringalgorithmisusedtoreducethenoiseafterbinarization.Theexternalcontourandinternalporesboundaryisextractedbythe"edge"functioninMATLAB,andthegeometricalmodelisreconstructed.Atwo-stepmeshalgorithmisadoptedtomeshthereconstructedgeometricalmodel.Accordingly,thefiniteelementmodelofaluminumfoamisestablishedbytheproposedmethodbasedonreconstructiongeometricalmodel.Thecompressionbehaviorofaluminumfoamisobtainedat25℃,100℃,200℃byABAQUS,andgoodagreementswithexperimentsareachievedbyapplyingthepresentreconstructionalgorithmandmodelingmethod.
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: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: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:Nucleon-nucleon(NN)correlationsandtheirisospindependenceinasymmetricnuclearmatterareofgreatnterestsincetheyarecloselyrelatedtothestructureofneutron-richnuclei[1],particleproductioninheavy-ionollisions[2],andneutron-starphysics[3].Themany-bodycorrelationsamongnucleonscanbedirectlyreflectedintheneutronandprotonspectralfunctions[4],andthelattermayplayanimportantroleinunderstandingthenatureftheNNcorrelations,especiallytheshort-rangeandtensorcorrelationsinasymmetricnuclearmatter.
简介:Regardforthefuzzinessandtherandomnessinsomeacousticfields,amethodforthenumericalanalysisofthe2DacousticfieldwithFuzzy-Randomparameterswasproposedbasedontheequivalentconversionofinformationentropy.Intheproposedmethod,afuzzyrandomacousticfieldwastreatedasapurefuzzyacousticfieldorapurerandomacousticfieldbytransformingallthevariablesintofuzzyvariablesorrandomvariables.Perturbationfiniteelementmethodsforanalyzingthetwo-dimensionalacousticfuzzyandrandomfieldarededuced.Thesoundpressureresponseofa2Dacoustictubeandthe2Dacousticcavityofacarwithfuzzy-randomparameterswereanalyzedbytheproposedmethodandtheMonteCarlomethod,theresultsshowthattheproposedmethodcanbewellappliedtothenumericalanalysisofthe2Dacousticfieldwithfuzzy-randomparameters,andhasgoodprospectofengineeringapplication.
简介:ThecaptureoforthophosphatesandtotalphosphorusfromthePudongCanalriverinthePudongDistrictofShanghaibyTiO2nanoparticlesisstudiedusingarotatingphotoreactorandthenano-TiO2photocatalystDegussaP25.TheeffectsofUVirradiationintensityinarangeof20-74mW/cm2.theloadingoftheTiO2nanoparticlesinarangeof0.05-0.1g/L,irradiationtimeupto4h,andpHvaluesinarangeof2-10.5onthecaptureefficiencyareinvestigated.TheresultsshowthatthecaptureoforthophosphatesandtotalParesignificantlyenhancedbyUVirradiation;ataloadingof0.1g/Landanirradiationintensityabove36mW/cm2,orthophosphatesandtotalphosphorusarerapidlycapturedbyTiO2nanoparticles,causinganobservedreductionfrom0.4mg/Ldownto0.02mg/L.pHvaluesinarangeof2-10.5havelittleeffectonthecaptureefficiencyoforthophosphatesandtotalphosphorus.