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简介：Wediscussthedynamicsofultrashortpulsedlaserexcitationinbulkopticalsilica-basedglasses(fusedsilicaandborosilicateBK7)well-abovethepermanentmodificationthreshold.Weindicatesubsequentstructuralandthermomechanicalenergyrelaxationpathsthattranslateintopositiveandnegativerefractiveindexchanges,compressionandrarefactionzones.Iffastelectronicdecayoccursatlowexcitationlevelsinfusedsilicaviaself-trappingofexcitons,forcarrierdensitiesinthevicinityofthecriticalvalueattheincidentwavelength,persistentlong-livingabsorptivestatesindicatetheachievementoflowviscositymatterstatesmanifestingpressurerelaxation,rarefaction,voidopeningandcompactionintheneighboringdomains.Anintermediateps-longexcitedcarrierdynamicsisobservedforBK7intherangecorrespondingtostructuralexpansionandrarefaction.Theamountofexcitationandthestrengthofthesubsequenthydrodynamicevolutioniscriticallydependentonthepulsetimeenvelope,indicativeofpotentialoptimizationschemes.

简介：Polyamide-1010sampleswereirradiatedinvacuumatroomtemperaturebyCobalt-60γ-rays.Thefreeradicalsformedinirradiationwerestudiedbymeansofelectronspinresonance（ESR）techniques.TheESRspectraconsistedofaquartetandasuperimposedsingletwhichwereattributedtoradical-CO-NH-CH-CH2and-CH2-C=O,respectively.TheeffectsoftemperatureandcrystaUinityontheradicalswerediscussedandthemechanismfortheproductionanddecayoftheradicalswasalsoproposed.

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简介：TheultrafastdynamicprocessinsemiconductorGeirradiatedbythefemtosecondlaserpulsesisnumericallysimulatedonthebasisofvanDrielsystem.Itisfoundthatwiththeincreaseofdepth,thecarrierdensityandlatticetemperaturedecrease,whilethecarriertemperaturefirstincreasesandthendrops.ThelaserfluencehasagreatinfluenceontheultrafastdynamicalprocessinGe.Asthelaserfluenceremainsaconstantvalue,thoughtheoverallevolutionofthecarrierdensityandlatticetemperatureisalmostindependentofpulsedurationandlaserintensity,increasingthelaserintensitywillbemoreeffectivethanincreasingthepulsedurationinthegenerationofcarriers.IrradiatingtheGesamplebythefemtoseconddoublepulses,theultrafastdynamicalprocessofsemiconductorcanbeaffectedbythetemporalintervalbetweenthedoublepulses.

简介：UltraHighMolecularWeightPolyethylene(UHMWPE)hasbeenwidelyusedasabearingmaterialforartificialjointreplacementoverfortyyears.Itisusuallycrosslinkedbygammaraysirradiationbeforeitsimplantationintohumanbody.Inthisstudy,UHMWPEandUHMWPE/nano-hydroxyapatite(n-HA)compositewerepreparedbyvacuumhot-pressingmethod.Thepreparedmaterialswereirradiatedbygammaraysinvacuumandmoltenheattreatedinvacuumjustafterirradiation.Theeffectoffillingn-HAwithgammairradiationontribologicalpropertiesofUHMWPEwasinvestigatedbyusingfrictionandwearexperimentalmachine(modelMM-200)underdeionizedwaterlubrication.Micro-morphologyofwornsurfacewasobservedbymetallographicmicroscope.Contactangleandhardnessofthematerialswerealsomeasured.Theresultsshowthatcontactangleandhardnessarechangedbyfillingn-HAandgammairradiation.Frictioncoefficientandwearrateunderdeionizedwaterlubricationarereducedbyfillingn-HA.Whilefrictioncoefficientisincreasedandwearrateisreducedsignificantlybygammairradiation.Thewornsurfaceofunfilledmaterialismainlycharacterizedasadhesivewearandabrasivewear,andthatofn-HAfilledmaterialismainlycharacterizedasabrasivewear.Aftergammairradiation,thedegreesofadhesiveandabrasivewearforunfilledmaterialandabrasivewearofn-HAfilledmaterialaresignificantlyreduced.Unfilledandfilledmaterialsafterirradiationaremainlyshownasslightfatiguewear.TheresultsindicatethatUHMWPEandUHMWPE/n-HAirradiatedatthedoseof150kGycanbeusedasbearingmaterialsinartificialjointsforitsexcellentwearresistancecomparedtooriginalUHMWPE.

简介：Inthepresentwork,theLEDchipwasirradiatedbyusing59.6MeVNionsinaterminalchamberoftheSector-focusedcyclotron(SFC)intheNationalLabortaryofHeavy-ionAcceleratorsinLanzhou.The63MeVNionspenetratedthroughagoldfoilandscatteredinalargearea.Theenergyofionwasreducedto59.6MeVafterscatteringofthegoldfoil.TheLEDwasprovidedbytheSemiconductorLightingCenterinInstituteofSemiconductorinBeijing.TheluminencesoftheLEDbefore/afterirradiationweretestedthroughaintegratingsphereinSemiconductorLightingCenterinInstituteofSemiconductorinBeijing.Theluminancewastestedunderacurrentof350mA.Fig.1showstherelationshipbetweentheluminencesandtheirradiationfluences.Theirradiationledto

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简介：Heavyionbeamsaregenerallyrecognizedasoneofpowerfulmutagensinplantbreedingtogeneratenewmutantswithidealorusefulagronomiccharacters[1].12C6+ionbeams(80MeV/u)acceleratedbyHeavyIonResearchFacilityinLanzhou(HIRFL)wereusedtoirradiatewheatsamples,oneofthemajorwheatvarietiesinQinghaiprovince,namedGaoyuan448.Theradiationdosesrangedfrom10to200Gy.Theirradiatedsamples,controls,andanothermajorwheatvarietynamedAbowereplantedinfarmlocatinginLeducountyofQinghaiprovincein2014.

简介：Tostudytheroom-temperaturestabledefectsinducedbyelectronirradiation,commercialborosilicateglasseswereirradiatedby1.2MeVelectronsandthenultraviolet(UV)opticalabsorption(OA)spectraweremeasured.Twocharacteristicbandswererevealedbeforeirradiation,andtheywereattributedtosilicondanglingbond(E’-center)andFe3+species,respectively.TheexistenceofFe3+wasconfirmedbyelectronparamagneticresonance(EPR)measurements.Afterirradiation,theabsorptionspectrarevealedirradiation-inducedchanges,whilethecontentofE’-centerdidnotchangeinthedeepultraviolet(DUV)region.TheslightlyreducedOAspectraat4.9eVwassupposedtotransformFe3+speciestoFe2+speciesandthistransformationleadstotheappearanceof4.3eVOAband.Bycalculatingintensityvariation,thetransformationofFewasestimatedtobeabout5%andtheopticalabsorptioncrosssectionofFe2+speciesiscalculatedtobe2.2timeslargerthanthatofFe3+species.Peroxylinkage(POL,≡Si–O–O–Si≡),whichresultsina3.7eVOAband,isspeculatednottobefromSi–ObondbreakbutfromSi–O–Bbond,Si–O–Albond,orSi–O–Nabondbreak.Theco-presencedefectwithPOLisprobablyresponsiblefor2.9-eVOAband.

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简介：Thepost-curekineticsofelectronbeam(EB)curingofepoxyresininitiatedbydiaryiodiniumwasinvestigated.Thepost-curereactionfitsfirstorderreactionkinetics.Thereactionrateconstantincreaseswithincreasingtreatmenttemperatureofpost-cure.Thereactionrateofpost-cureismuchlowerthantherateofitsreactiononelectronbeamtreatment.

简介：Theeffectofγ-rayirradiationonthemechanicalpropertiesofhighdensitypolyethylene(HDPE)filledwithsericite-tridymite-cristobalite(STC)wasstudied.Theex-perimentalresultsshowthatγ-rayirradiationcanimprovetheaffinitybetweenHDPEandSTC,andthedispersionofSTCinHDPEmatrix.ComparedwithHDPE/STC(80/20)blend,theyieldstressandimpactstrengthofirradiatedHDPE(10kGy)/STC(80/20)blendareincreasedfrom22.8MPaand70J/mto28.5MPaand144J/m.TheyieldstressandimpactstrengthofHDPE/irradiatedHDPE/STC(48/32/20)are27.8MPaand210J/m,respectively.

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简介：Duetoitsmajorroleinmaintainingthewater-retainingpropertiesoftheepidermis,ceramideisofgreatcommercialpotentialincosmeticsandpharmaceuticalssuchashairandskincareproducts.However,currentsyntheticapproachesforceramidearetediousandtime-consumingforindustrialapplications.Therefore,itisdesirabletofindanalternativecost-efficientandhighly-yieldmethodforobtainingthevaluableproducts.Inpresentstudy,thepotentialofproducingceramidethroughenzymatichydrolysisofsphingomyelinwithenzymeirradiatedby808nmlighthasbeenstudied.Withenzymeirradiatedby808nmlight,itsactivitycanbeenhancedandreactionspeedcanbeincreasedsignificantly.

简介：TheagingbehaviorsofirradiatedtungstenbyhighenergySi3＋andH＋ionsaremainlyinvestigatedusinginternalfriction（IF）methodcombinedwithSEMtechnology.TheSEManalysisindicatesthatmoresevereirradiationdamageappearsinthesurfaceofsimultaneousdualSi3＋H＋irradiatedspecimenthanthatinthesequentialdualSi3＋H＋irradiatedspecimenorthesingleSi3＋irradiatedspecimensbecauseofthesynergisticeffectofSiandHirradiation.TheIFbackgroundoftheirradiatedsampleisaboutoneorderofmagnitudehigherthanthatoftheunirradiatedsampleowingtotheexistenceofhighdensityfreshdislocationsinducedbySi/Hirradiation,InthesequentialdualSi3＋andH＋irradiatedspecimen,thehydrogenSnoek-Ke-Koster（SKK）peakassociatedwiththemovementofdislocationsdragginghydrogenatomsisobservedanditsheightdecreaseswithagingtimeatroomtemperature.AsforthesimultaneousdualSi3＋H＋irradiatedspecimen,however,thereisnosuchhydrogenSKKpeak.Thereasoncanbeexplainedashydrogendiffusionandpinningeffectofdislocations.

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