学科分类
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127 个结果
  • 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.

  • 标签: NANOINDENTATION ALLOY IRRADIATED
  • 简介:AnovelmethodformodelingcellularmaterialsisproposedbasedonMATLABimageprocessingandsynchrotronX-raycomputedtomographyscanningtoobtainanaccuratecalculationresultofaluminumfoambasedonfiniteelementmodel.Themaximumentropyalgorithmisemployedtoobtainthebinarizationimage,andthemedianfilteringalgorithmisusedtoreducethenoiseafterbinarization.Theexternalcontourandinternalporesboundaryisextractedbythe"edge"functioninMATLAB,andthegeometricalmodelisreconstructed.Atwo-stepmeshalgorithmisadoptedtomeshthereconstructedgeometricalmodel.Accordingly,thefiniteelementmodelofaluminumfoamisestablishedbytheproposedmethodbasedonreconstructiongeometricalmodel.Thecompressionbehaviorofaluminumfoamisobtainedat25℃,100℃,200℃byABAQUS,andgoodagreementswithexperimentsareachievedbyapplyingthepresentreconstructionalgorithmandmodelingmethod.

  • 标签: 泡沫铝 有限元建模 材料响应 重建方法 三维几何 MATLAB
  • 简介:在这份报纸,用水泡功能,我们构造一个长方体元素解决第四份订单在三种尺寸的椭圆形的单个不安问题。我们证明nonconformingC0长方体元素关于不安参数一致地在精力标准收敛。[从作者抽象]

  • 标签: 奇异摄动问题 非协调元 一致收敛 椭圆 四阶 3-D
  • 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].

  • 标签: 纳米晶体 超晶格 自组装 四氧化三铁 纳米结构材料 超顺磁性氧化铁
  • 简介:Extractionofthein-mediumpropertiesofstrangeparticlesfromheavy-ioncollisionsisverycomplicated,sincehenucleardensityvariesintheevolutionofnucleus-nucleuscollisions.Toavoidtheuncertaintiesofthebaryonensitiesduringthestageofstrangeparticleproduction,onecaninvestigateproton-nucleuscollisionswheretheucleardensityisdefinitearoundthesaturationdensity.DynamicsofstrangeparticlesproducedintheprotoninduceduclearthereactionsnearthethresholdenergieshasbeeninvestigatedwithintheLanzhouquantumoleculardynamics(LQMD)transportmodel.Thein-mediummodificationsonparticleproductionindensenuclearmatterareconsideredthroughthecorrectionstotheelementarycrosssectionsviatheeffectivemassandhemean-fieldpotentials[1].

  • 标签: STRANGE PARTICLES In-medium
  • 简介:Nanowireshaveattractedmoreandmoreinterestinrecentyearsduetotheiruniquepropertiescomparedtobulkmaterials[1].Thequitedifferentpropertiespossessedbynanowiresaremainlycausedbytheirhighsurface-tovolumeratio[2].Behaviorsofnanowiresunderirradiationconditionshavealsoattractedintensiveattentionintheseyears[3??5].Ithasbeenproposedthatnanowiresmayberadiationresistancebecausetheirlargesurface-to-volumeratio,andmeanwhilethesurfacearetheperfectsinksfordefectscreatedintheradiationprocess[3].

  • 标签: Molecular Dynamics STUDY
  • 简介:Sweetsorghum,theworld'sfifthmostimportantcerealafterrice,corn,wheatandbarley,isaveryattractivesourceforbiomassproduction.Thisrawmaterialcomplementssugarcaneproductionandisemergingastheidealfeedforanimalsandfortheproductionofthefirst-generationofbiofuels,suchasethanolandvalue-addedchemicals.Atpresent,mostofthestudiesaboutsweetsorghumfocusonutilization(suchasethanolproduction),andthestudyofsugeraccumulationinstemarerarely.

  • 标签: SUGAR Accumlation SORGHUM
  • 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.

  • 标签: PROGRESS MUTATION BREEDING
  • 简介:以胺甲基苯并咪唑和水杨醛为原料设计合成了一个苯并咪唑衍生物荧光探针,通过荧光分光光度法和紫外分光光度法探寻其对常见阴阳离子的选择性识别性能.研究结果表明,Cu2+对合成得到的苯并咪唑衍生物具有荧光猝灭——“关”的作用,而S2O72-对该荧光猝灭体系具有荧光恢复——“开”的作用.据此,提出了具有实现对Cu2+,S2O72-的荧光“关-开”型探针.

  • 标签: 苯并咪唑衍生物 荧光探针 阴离子 阳离子
  • 简介:Duetotheiruniqueadvantagesinphysicsandbiology,heavyionbeams,withhighmutationrateandwidemutationspectrum,havebeenwidelyusedinplantbreedingasanovelandefficientphysicalmutagen.Inthiswork,Arabidopsisthaliana(197#),whichdisplayeddecreasedfertility,wasinducedbycarbonionbeamsacceleratedbytheHeavyIonResearchFacilityinLanzhou(HIRFL).InordertodeterminethediscrepanciesbetweenWTandmutantplants,aseriesofdevelopmentindexeswereanalyzedduringthereproductivegrowthstage.

  • 标签: REPRODUCTIVE Analysis ARABIDOPSIS
  • 简介:沙粒病毒(Arenaviruses)遍布全球,其中的拉沙热病毒可引起致命的拉沙热.通过应用比较分子场分析(CoMFA)和比较相似性指数分析法(CoMSIA)对47个广谱沙粒病毒抑制剂进行了三维定量构效关系(3D-QSAR)分析.使用立体场、静电场、疏水场和氢键受体场组合获得最优模型CoMSIA的统计结果为Q2=0.518,R2ncv=0.972,R2pre=0.911,说明该模型的可靠性和较好预测能力.此外,模型等势线图直观地解释了分子结构与其活性的关系,为进一步设计新型高效的沙粒病毒抑制剂提供了理论依据.

  • 标签: 沙粒病毒 LASV 苯并咪唑衍生物 三维定量构效关系
  • 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.

  • 标签: TRACK VIBRATIONAL MUSCOVITE
  • 简介:Nucleon-nucleon(NN)correlationsandtheirisospindependenceinasymmetricnuclearmatterareofgreatnterestsincetheyarecloselyrelatedtothestructureofneutron-richnuclei[1],particleproductioninheavy-ionollisions[2],andneutron-starphysics[3].Themany-bodycorrelationsamongnucleonscanbedirectlyreflectedintheneutronandprotonspectralfunctions[4],andthelattermayplayanimportantroleinunderstandingthenatureftheNNcorrelations,especiallytheshort-rangeandtensorcorrelationsinasymmetricnuclearmatter.

  • 标签: CORRELATIONS AMONG NUCLEONS
  • 简介:10mol%CuIcombinedwiththeDMEDAligandcanefficientlycatalyzetheN-arylationof2-arylindoleswitharyliodidesandarylbromidesingoodtoexcellentyields.Thearylhalidesbearingelectron-richorelectron-deficientfunctionalgroupscanbewelltoleratedunderthismildreactionconditions.

  • 标签: 芳基卤化物 芳基化 催化 芳基碘化物 反应条件
  • 简介:Regardforthefuzzinessandtherandomnessinsomeacousticfields,amethodforthenumericalanalysisofthe2DacousticfieldwithFuzzy-Randomparameterswasproposedbasedontheequivalentconversionofinformationentropy.Intheproposedmethod,afuzzyrandomacousticfieldwastreatedasapurefuzzyacousticfieldorapurerandomacousticfieldbytransformingallthevariablesintofuzzyvariablesorrandomvariables.Perturbationfiniteelementmethodsforanalyzingthetwo-dimensionalacousticfuzzyandrandomfieldarededuced.Thesoundpressureresponseofa2Dacoustictubeandthe2Dacousticcavityofacarwithfuzzy-randomparameterswereanalyzedbytheproposedmethodandtheMonteCarlomethod,theresultsshowthattheproposedmethodcanbewellappliedtothenumericalanalysisofthe2Dacousticfieldwithfuzzy-randomparameters,andhasgoodprospectofengineeringapplication.

  • 标签: 数值分析方法 随机参数 模糊性 声场 二维 蒙特卡罗方法
  • 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.

  • 标签: 纳米二氧化钛光催化剂 紫外光照射 捕获 总磷 二氧化钛纳米粒子 地表水