简介：用微波高温固相法合成了Er^3+单掺Lu2O3,Li^+与Er^3+共掺Lu2O3及Li^+,Zn^2+,Mg^2+掺杂Lu2O3∶Er^3+的荧光粉。实验表明金属离子Li^+、Zn^2+、Mg^2+、Er^3+掺杂Lu2O3,不影响Lu2O3的立方晶相。扫描电子显微镜测量表明,Li^+掺杂可以有效改善粉体的分散性和形貌,Li^+,Zn^2+,Mg^2+共掺杂获得的粉体颗粒分布更加均匀,粒径范围为80~100nm。379nm激发下,Li^+与Er^3+共掺样品发光较单掺Er^3+样品在565nm处的发光增强了4.5倍,而Li^+、Zn^2+、Mg^2+与Er^3+共掺样品较其发光增强5.3倍。980nm激发下,Li^+与Er^3+共掺样品,Li^+、Zn^2+、Mg^2+与Er^3+共掺样品的发光分别比单掺Er^3+样品在565nm处发光增强23倍与39倍,在662nm处发光强度分别增强20倍与43倍。379nm激发下,较单掺Er3+的样品,掺杂Li^+的样品和Li^+,Zn^2+,Mg^2+和Er^3+共掺的样品荧光寿命均有所增加,而Zn^2+、Er^3+共掺及Mg^2+、Er^3+共掺样品的荧光寿命则有所缩短。

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简介：Asafundamentalpropertyofnuclei,atomicmassesarewidelyusedinmanydomainsofscienceandengineering.Areliableatomicmasstablederivedfromtheexperimentaldata,wheretheatomicmassesandtherelevantexperi-mentalinformationcanbefoundconveniently,isinhighdemandbytheresearchcommunity.Tomeetthedemands,theAtomicMassEvaluation(AME)wasinitiatedin1950'sandaseriesofAMEmasstableshavebeenpublishedeversince.CurrentlytheAMEservestheresearchcommunitybyprovidingthemostreliableandcomprehensiveinformationrelatedtotheatomicmasses.ThenewatomicmassevaluationAME2016waspublishedintheMarchissueofChinesePhysicsCastwocom-plementarypapers[1;2].

简介：LargeGdCa4O(BO3)3crystalhasbeengrownbytheCzochralskimethod.ThequalityofGdCa4(BO3)3crystalwasassessedbywhite-beamsynchrotronradiationtopography.Ithasbeenfoundthatthereisasub-grainboundaryintheGdCa4O(BO3)3crystal.TheboundarydividesthelargeGdCa4O(BO3)3crystalintotwoindividuals.Duetothemisorientationbetweenthetwoindividuals,theimageshiftscanbeobservedinthesynchrotrontopopraphs.BasedonthemisorientationdeterminedbyhighresolutionX-raydiffractometer,theimageshiftswerecalculatedforseveralreflections.ThecalculationsareinagreementwiththemeasurementsfromthetopogrphsveryWell.Inaddition,theformationmechanismofsub-grainboundaryisdiscussed.2001ElsevierscienceB.V.Allrightsreserved.

简介：CO2methanationhasbeenahottopicbecauseofitsimportantapplicationinthespacecraftandpotentialutilizationofcarbondioxide.Nickelcatalystisactiveforthisreaction.However,itsactivitystillneedstobeimproved.Dielectricbarrierdischarge(DBD)plasma,initiatedatambientconditionandoperatedat~150°C,hasbeenemployedinthisworkfordecompositionofnickelprecursortoprepareNi/MgAl2O4.Theplasmadecompositionresultsinhighdispersion,uniquestructure,enhancedreducibilityofNiparticlesandpromotedcatalyst-supportinteraction.AnimprovedactivityofCO2methanationwithahigheryieldofmethanehasbeenachievedovertheplasmadecomposedcatalyst,comparedtothecatalystpreparedthermally.Forexample,themethaneyieldoftheplasmapreparedcatalystis71.8%at300°Cbutitis62.9%overthethermalpreparedcatalyst.ThecatalystcharacterizationconfirmedthatCO2methanationovertheDBDplasmapreparedcatalystfollowspathwayofCOmethanation.

简介：Thepaperrepresentsarigoroustreatmentoftheunderlyingquantumtheory,notjustinwordsbutprovidingtheunderlyingtechnicaldetails,astowhymatteroccupiessolargeavolumeanditsintimateconnectionwiththePauliexclusionprinciple,asmoreandmorematterisputtogether,aswellasofthecontractionorshrinkageof'bosonicmatter',uponcollapse,forwhichthePauliexclusionisabolished.Fromthederivedexplicitboundsofintegralsofpowersoftheparticlenumberdensities,explicitboundsonprobabilitiesoftheoccurrencesoftheeventsjustdescribedareextracted.Theseprobabilitiesleadonetoinferthechangeofthe'size'orextensionofsuchmatter,uponexpansionorcontraction,respectively,astheircontentisincreased.

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简介：Afacilestep-by-stepapproachisdevelopedforsynthesizingthehigh-efficiencyandmagneticrecyclableFe_3O_4@SiO_2@Ag@Nitrepang-likenanocomposites.ThismethodinvolvescoatingFe_2O_3nanorodswithauniformsilicalayer,reductionin10%H_2/AratmospheretotransformtheFe_2O_3intomagneticFe_3O_4,andfinallydepositingAg@Nicore-shellnanoparticlesontheL-lysinemodifiedsurfaceofFe_3O_4@SiO_2nanorods.Thefabricatednanocompositesarefurthercharacterizedbyx-raydiffraction,transmissionelectronmicroscopy,scanningelectronmicroscope,Fouriertransforminfraredspectroscopy,andinductivelycoupledplasmamassspectroscopy.TheFe_3O_4@SiO_2@Ag@Nitrepang-likenanocompositesexhibitremarkablyhighercatalyticefficiencythanmonometallicFe_3O_4@SiO_2@AgnanocompositestowardthedegradationofRhodamineB(RhB)atroomtemperature,andmaintainsuperiorcatalyticactivityevenaftersixcycles.Inaddition,thesesamplescouldbeeasilyseparatedfromthecatalyticsystembyanexternalmagnetandreused,whichshowsgreatpotentialapplicationsintreatingwastewater.

简介：磁铁矿(Fe3有不同尺寸和形状的O4)nanoparticles被热分解方法综合。二条途径，非注射一个壶和热注射的方法，被设计详细调查生长机制。nanoparticles的尺寸和形状被调整先锋集中和持续时间时间决定，这被发现，它能好在我们的合成系统基于LaMer模型由机制解释了。monodisperseFe3O4nanoparticles从5nm有一条吝啬的直径到16nm，和形状进化从对球形三角形、立方。磁性是尺寸依赖者，和Fe3在关于在房间温度和最大的浸透磁化的5nm展览superparamagnetic性质的小尺寸的O4nanoparticles来临到78emu/g，而Fe3O4nanoparticles当直径增加到大约16nm时，开发铁磁性的性质。

简介：Multilayerblackphosphorus（BP）nanoplateletsofdifferentthicknesseswerepreparedbytheliquidphaseexfoliationmethodanddepositedontoyttriumaluminumgarnetsubstratestoformsaturableabsorbers（SAs）.Thesewerecharacterizedwithrespecttotheirthickness-dependentsaturableabsorptionpropertiesat3μm.TheBP-SAswereemployedinapassivelyQ-switchedEr:Lu2O3laserat2.84μm.ByusingBPexfoliatedindifferentsolvents,stablepulsesasshortas359nsweregeneratedatanaverageoutputpowerofupto755mW.Therepetitionrateintheexperimentwas107kHz,correspondingtoapulseenergyof7.1μJ.TheseresultsprovethatBP-SAshaveagreatpotentialforopticalmodulationinthemid-infraredrange.

简介：Amolybdenumdisulfide（MoS2）saturableabsorberwasfabricatedbythermallydecomposingtheammoniumthiomolybdate.ByusingtheMoS2absorber,acompactdiode-pumpedpassivelyQ-switchedTm:GdVO4laserhasbeendemonstrated.AstableQ-switchedlaserwithrepetitionratesfrom25.58to48.09kHzwasachieved.Maximumaverageoutputpowerwas100mWwiththeshortestpulsedurationof0.8μs.Maximumpulseenergyis2.08μJatcenterof1902nm.

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简介：AnewlayeredCu-basedoxychalcogenideBa3Fe2O5Cu2S2hasbeensynthesizedanditsmagneticandelectronicpropertieswererevealed.Ba3Fe2O5Cu2S2isbuiltupbyalternativelystacking[Cu2S2]2-layersandironperovskiteoxide[（FeO2）（BaO）（FeO2）]2-layersalongthecaxisthatareseparatedbybariumionswithFe3+fivefoldcoordinatedbyasquare-pyramidalarrangementofoxygen.Fromthebondvalencearguments,weinferredthatinlayeredCuCh-based（Ch=S,Se,Te）compoundsthe+3cationinperovskiteoxidesheetprefersasquarepyramidalsite,whilethelowervalencecationprefersthesquareplanarsites.Thestudiesonsusceptibility,transport,andopticalreflectivityindicatethatBa3Fe2O5Cu2S2isanantiferromagneticsemiconductorwithaNe′eltemperatureof121Kandanopticalbandgapof1.03eV.Themeasurementofheatcapacityfrom10Ktoroomtemperatureshowsnoanomalyat121K.TheDebyetemperatureisdeterminedtobe113K.TheoreticalcalculationsindicatethattheconductionbandminimumispredominantlycontributedbyO2pand3dstatesofFeionsthatantiferromagneticallyarrangedinFeO2layers.TheFe3dstatesarelocatedatlowerenergyandresultinanarrowbandgapincomparisonwiththatoftheisostructuralSr3Sc2O5Cu2S2.

简介：QuantumdynamicscalculationsforthetitlereactionH(2S)+S2(X3-Σg)→SH(X2Π)+S(3P)areperformedbyusingagloballyaccuratedoublemany-bodyexpansionpotentialenergysurface[J.Phys.Chem.A1155274(2011)].TheChebyshevrealwavepacketpropagationmethodisemployedtoobtainthedynamicalinformation,suchasreactionprobability,initialstate-specifiedintegralcrosssection,andthermalrateconstant.Itisfoundnotonlythatthereisareactionthresholdnear0.7eVinbothreactionprobabilitiesandintegralcrosssectioncurves,butalsothatboththeprobabilityandcrosssectionincreasefirstlyandthendecreaseasthecollisionenergyincreases.Theexistenceoftheresonancestructureinboththeprobabilityandcrosssectioncurvesisascribedtothedeeppotentialwell.Thecalculationoftherateconstantrevealsthatthereactionoccurringonthepotentialenergysurfaceoftheground-stateHS2isslowtotakeplace.

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简介：Inthiswork,theinfluenceofCO2onthestructuralvariationandcatalyticperformanceofNa2WO4/Mn/SiO2foroxidativecouplingofmethanetoethylenewasinvestigated.ThecatalystwaspreparedbyimpregnationmethodandcharacterizedbyXRD,RamanandXPStechniques.AppropriateamountofCO2inthereactantgasesenhancedtheformationofsurfacetetrahedralNa2WO4speciesandpromotedthemigrationofOinMOx,Na,Wfromthecatalystbulktosurface,whichwerefavorableforoxidativecouplingofmethane.WhenthemolarratioofCH4/O2/CO2was3/1/2,enrichedsurfacetetrahedralNa2WO4speciesandhighsurfaceconcentrationofOinMOx,Na,Wweredetected,andthenhighCH4conversionof33.1%andhighC2H4selectivityof56.2%wereobtained.WithfurtherincreaseofCO2inthereagentgases,thecontentofactivesurfacetetrahedralNa2WO4speciesandsurfaceconcentrationofOinMOx,Na,Wdecreased,whilethatofinactivespecies(MnWO4andMn2O3)increaseddramatically,leadingtolowCH4conversionandlowC2H4selectivity.ItcouldbespeculatedthatNa2WO4crystalwastransformedintoMnWO4crystalwithexcessiveCO2addedunderthereactionconditions.PretreatmentofNa2WO4/Mn/SiO2catalystbymoderateamountofCO2beforeOCMalsopromotedtheformationofNa2WO4species.

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简介：Theabinitiogeneralizedgradientapproximation（GGA）＋Ustudyofmultiferroic（La0.5Bi0.5）2FeCrO6inpnmastructureandferri-magneticorder,includingHubbardcorrections（U-4.1eV）fortransitionmetal/rareearthd-electronswith20atomscell,showsoptimumlocalmagneticmomentsof（Cr^3＋,Fe^3＋）equalto（-2.56,4.14）#Bandanidealspin-downbandgapof1.54eV.Tuned-bandgapLa-substituteddoubleoxideperovskitesBFCOshouldexhibitenhancedvisible-lightabsorptionandcarriermobility,thuscouldbeconvenientlightabsorbersandthenefficientalternativestowide-gapchalcopyriteabsorber-basedsolarcellsfailingtoachievehighestpowerconversionefficiencies,andevencompetewiththeirmetal-organichalideperovskitescounterparts.