简介：Theshapeofnanostructurehasimportanteffectsontheirproperties,thereforeinthisstudy,wehavepreparedandcharacterizedthreedifferentmorphologiesofWO3nanostructuresi.e.nanorod,nanosphereandnanoplateforsurveyingshapeeffectontheirphotocatalyticpropertiestowarddegradationofRhodamineB(RhB)dye.ObtainedresultsshowthatnanoplateWO3incomparisonwithothershasthebestphotocatalyticactivity.AccordingtoSEM,andphotocatalyticdegradationresults,thereasonforthisbehavioristhesharpedgesandcornersofWO3nanoplates.Becauseoftheirlowcoordinationnumber,atomslocatedintheedgesandcornersoftheWO3nanoplateshavemoreactivity,adsorbmoreRhBandthereforegivemorephotocatalyticactivitytotheWO3nanoplates.UsingofdifferentscavengersshowedthathydroxylradicalsaremainlyresponsibleforphotocatalyticactivityofWO3nanoplatesandnanospheresbutforWO3nanorods,superoxideradicalsarethemainphotocatalyticdegradationagents.

简介：AUltrafineamorphousNiBalloywaspreparedviachemicalreductionmethod;ItsstructuresduringthecrystallizatioinprecesswascharacterizedbysuchtechniquesasDifferentialthermalanalysis(DTA),X-rayabsorptionfinestructure(XAFS)andX-raydiffraction(XRD),andcorrelatedtothecatalyticpropertiesforbenzenehydrogenation.ItwasfoundthatthecrystallizationofamorphousNiBalloywascarriedoutintwosteps,asindicatedbytwoexothermicpeakscenteredat598and652Krespectively.Duringthefirststep.twometastablecrystallinephases,i.e.,Ni3BandanoaocrstallineNiphase(Ni-richNiBalloy),wereformed.Furtherannealingathighertemperatureof652KmayresultinthedecompositionofcrystallineNi3BandaggregationofnanocrystallineNi,thebenzenehydrogenationisoptimizedaroundtheannealingtemperatureof623K.ItmostprobablyresultsfromthemaximumamountofactivesiteonnanocrystallineNiformedbythermaltreatmentatappropriateannealingtemperature.

简介：Highlyefficientsheet-likeBiPO4/zeoliteandball-flower-likeBiPO4/zeolitehadbeensuccessfullysynthesizedbyastandardhydrothermalmethod.Theadditionofassistantreagentinthehydrothermalsystemispromisingtoobtainspecialmorphology.Theassistantreagent（EDTA）actsasagrowthmodifierofcrystal.Thepossibleformationmechanismsofsheet-likeBiPO4/zeoliteandball-flower-likeBiPO4/zeolitewereschematicallydiscussed.Adetailedstudyofsheet-likeBiPO4/zeoliteandball-flower-likeBiPO4/zeoliteimpactedonthephotodecolorationmethyleneblue（MB）solutionshowedthatthecompositehadahighlyreusableandstablepropertyforlong-runphotocatalyticapplication.

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简介：Nanostructuredironoxyhydroxide（FeOOH）thinfilmshavebeensynthesizedusinganelectrodepositionmethodonanickelfoam（NF）substrateandeffectofairannealingtemperatureonthecatalyticperformanceisstudied.Theas-depositedandannealedthinfilmswerecharacterizedbyX-raydiffraction（XRD）,X-rayphotoelectronspectroscopy（XPS）,fieldemissionscanningelectronmicroscopy（FE-SEM）andlinearsweepvoltammetry（LSV）todeterminetheirstructural,morphological,compositionalandelectrochemicalproperties,respectively.Theas-depositednanostructuredamorphousFeOOHthinfilmisconvertedintoapolycrystallineFe2O3withhematitecrystalstructureatahightemperature.TheFeOOHthinfilmactsasanefficientelectrocatalystfortheoxygenevolutionreaction（OER）inanalkaline1MKOHelectrolyte.Thefilmannealedat200°Cshowshighcatalyticactivitywithanonsetoverpotentialof240mVwithasmallerTafelslopeof48mV/dec.Additionally,itneedsanoverpotentialof290mVtothedrivethecurrentdensityof10mA/cm2andshowsgoodstabilityinthe1MKOHelectrolytesolution.

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简介：获得信号要求的electrocorticograms(ECoG)大脑活动从外皮的表面在被记录的一个侵略过程。相反，获得记录要求的脑电图(EEG)从头皮记录大脑活动的非侵略的过程出现，它允许EEG记录在健康的人上更容易被表现。在这个工作，以前过去常在动物ECoG上学习大脑活动的空间时间的模式的一种技术在EEG上为使用被改编。主要问题在解决增长在极间距离和过程上引入检测稳定的框架的问题上被集中。结果证明贝它和鲸鱼群妈活动的空间模式能被为特征抽取把稳定的框架用作时间标记也从EEG信号提取。这种改编技术使利用一个正常健康题目的认知、现象学的了解可能。

简介：Toinvestigatewhetherandhowmanualacupuncture(MA)modulatesbrainactivities,wedesignanexperimentwhereacupunctureatacupointST36oftherightlegisusedtoobtainelectroencephalograph(EEG)signalsinhealthysubjects.Weadopttheautoregressive(AR)BurgmethodtoestimatethepowerspectrumofEEGsignalsandanalyzetherelativepowersindelta(0Hz-4Hz),theta(4Hz-8Hz),alpha(8Hz-13Hz),andbeta(13Hz-30Hz)bands.OurresultsshowthatMAatST36cansignificantlyincreasetheEEGslowwaverelativepower(deltaband)andreducethefastwaverelativepowers(alphaandbetabands),whiletherearenostatisticaldifferencesinthetabandrelativepowerbetweendifferentacupuncturestates.InordertoquantifytheratioofslowtofastwaveEEGactivity,wecomputethepowerratioindex.ItisfoundthattheMAcansignificantlyincreasethepowerratioindex,especiallyinfrontalandcentrallobes.AlltheresultshighlightthemodulationofbrainactivitieswithMAandmayprovidepotentialhelpfortheclinicaluseofacupuncture.TheproposedquantitativemethodofacupuncturesignalsmaybefurtherusedtomakeMAmorestandardized.

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简介：PhotocatalyticH2productionhasemergedasoneofthemostcleanandpromisingrenewableenergysources.InspiteoftheeffortstoobtainefficientphotocatalystsabletoproduceH2fromSunlightandwater,thereisstilltheneedtopreparecheaperandenvironmentalfriendlierphotocatalysts.Phosphatebasedmaterialscouldbegoodcandidatestofulfilltheserequirements.InthismanuscriptwehavepreparedasetofmixedTi3+/Ti4+valence,open-frameworktitaniumphosphates（of-TiPO4）andmixedtitaniumoxide/phosphatederivatives（cr-TiP）,correlatingtheirstructureandcompositionwiththephotocatalyticactivityforH2production.Wedeterminedthatmixedtitaniumoxide/phosphatecrystallinephasesproducedenhancedH2evolutionunderSunsimulatedlightirradiationthanmixedTi3+/Ti4+valence,open-frameworktitaniumphosphatesandtitaniumoxidephases.

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简介：PtRu/SnO2/Ccatalystwaspreparedinapolyolprocess,followedbyreductiontreatmentandalkalineetching.X-raydiffraction,transmissionelectronmicroscopewithenergydispersivespectrometerandXrayphotoelectronspectroscopywereusedtocharacterizethemorphology,structureandcompositionofthecatalysts.COandmethanolelectro-oxidationactivitiesofthecatalystswereevaluatedbyCOstrippingvoltammetry,cyclicvoltammetryandchronoamperometrymeasurements.ReductiontreatmentofthepreparedPtRuSnO2/CcatalystinapolyolprocessinducedtheenrichmentofSnonthesurface,inhibitingmethanoldissolutionandCOadsorptiononPt.AlkalineetchingremovedSnorSnOxandthusexposedPtRuonthesurface,resultinginenhancedactivitiesforCOandmethanolelectro-oxidationduetothesynergyeffectsofPtRuonthesurfaceandSnspeciesbeneath.

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：BimetallicFe-Mnnanocatalystssupportedoncarbonnanotubes(CNTs)werepreparedusingmicroemulsiontechniquewithwater-to-surfactantratiosof0.4-1.6.ThenanocatalystswereextensivelycharacterizedbydifferentmethodsandtheiractivityandselectivityinFischer-Tropschsynthesis(FTS)havebeenassessedinafixed-bedmicroreactor.Thephysicochemicalpropertiesandperformanceofthenanocatalystswerecomparedwiththecatalystpreparedbyimpregnationmethod.Verynarrowparticlesizedistributionhasbeenproducedbythemicroemulsiontechniqueatrelativelyhighloadingofactivemetal.TEMimagesshowedthatsmallmetalnanoparticlesintherangeof3–7nmwerenotonlyconfinedinsidetheCNTsbutalsolocatedontheoutersurfaceoftheCNTs.Usingmicroemulsiontechniquewithwatertosurfactantratioof0.4decreasedtheaverageironparticlesizesto5.1nm.Thereductionpercentageanddispersionpercentagewerealmostdoubled.Activityandselectivitywerefoundtobedependentonthecatalystpreparationmethodandaverageironparticlesize.COconversionandFTSrateincreasedfrom49.1%to71.0%and0.144to0.289gHC/(gcath),respectively.WhiletheWGSratedecreasedfrom0.097to0.056gCO2/(gcath).C5+liquidhydrocarbonsselectivitydecreasedslightlyandolefinsselectivityalmostdoubled.

简介：Thepyrolyzedcarbonsupportedferrumpolypyrrole(Fe-N/C)catalystsaresynthesizedwithorwithoutselecteddopants,p-toluenesulfonicacid(TsOH),byafacilethermalannealingapproachatdesiredtemperatureforoptimizingtheiractivityfortheoxygenreductionreaction(ORR)inO2-saturated0.1mol/LKOHsolution.Theelectrochemicaltechniquessuchascyclicvoltammetry(CV)androtatingdiskelectrode(RDE)areemployedwiththeKoutecky-LevichtheorytoquantitativelyobtaintheORRkineticconstantsandthereactionmechanisms.ItisfoundthatcatalystsdopedwithTsOHshowsignificantlyimprovedORRactivityrelativetotheTsOH-freeone.TheaverageelectrontransfernumbersforthecatalyzedORRaredeterminedtobe3.899and3.098,respectively,forthecatalystswithandwithoutTsOH-doping.Theheat-treatmentisfoundtobeanecessarystepforcatalystactivityimprovement,andthecatalystpyrolyzedat600℃givesthebestORRactivity.Anonsetpotentialandthepotentialatthecurrentdensityof-1.5mA/cm2forTsOH-dopedcatalystafterpyrolysisare30mVand170mV,whicharemorepositivethanthosewithoutpyrolized.Furthermore,thecatalystdopedwithTsOHshowshighertolerancetomethanolcomparedwithcommercialPt/Ccatalystin0.1mol/LKOH.TounderstandthisTsOHdopingandpyrolyzedeffect,X-raydiffraction(XRD),scanningelectronmicroscope(SEM)andX-rayphotoelectronspectroscopy(XPS)areusedtocharacterizethesecatalystsintermsoftheirstructureandcomposition.XPSresultsindicatethatthepyrrolic-Ngroupsarethemostactivesites,afindingthatissupportedbythecorrespondencebetweenchangesinpyridinic-NcontentandORRactivitythatoccurwithchangingtemperature.SulfurspeciesarealsostructurallyboundtocarbonintheformsofC–Sn–C,anadditionalbeneficialfactorfortheORR.

简介：Thisworkreportsafacileandefficientseed-mediatedmethodforthesynthesisofdendriticplatinum(Pt)nanoparticles(NPs)atlowtemperaturesof55–60°Cinwater,usingL-ascorbicacidasareducingagentandsodiumcitrateasacappingagent.ItisfoundthatthedendriticPtNPs(10–150nm)arecomposedoftinyPtnanocrystals,whichnucleateandgrowthroughtheintroducedsmallerPtseedswithdiametersof3–5nm.FurtherinvestigationshowsthatthedendriticPtnanostructuresdisplayexcellentcatalyticperformanceinanaqueous-phasearomaticketonehydrogenationreaction,including:(i)acetophenoneconversionrateof>90%,withsmallerdendriticPtNPs(10–46nm)offeringahigherconversionefficiency;(ii)highchemoselectivitytowardcarbonylgroup(90.6%–91.5%),e.g.,theselectivityto1-phenylethanolis~90.1%withnearly100%acetophenoneconversionfor10nmdendriticPtNPswithin60min,undermildreactionconditions(20°C,1.5barH2pressure,and1.5mol%catalyst).Thehighcatalyticactivity,selectivityandstabilityofthedendriticPtnanostructuresundertheorganicsolvent-freeconditionsmakethempromisingformanypotentialapplicationsingreencatalyticconversionofhydrophilicbiomassderivedcompounds.

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