简介：TherewasasignificantcatalyticeffectoftraceGd(III)ionsontheoxidativereactionofpotassiumpersulfatewithSaffronTintheaceticacid–sodiumacetatebuffersolution.Thus,acatalytickineticfluorimetrymethodforthedeterminationoftraceGd(III)ionswasestablished.Thefactorssuchasacidity,concentrationofreagents,reactiontime,andtemperatureaswellasinfluenceofcoexistingionswerediscussed.Theoptimumreactionconditionswereestablished.Theapparentrateconstantandapparentactivationenergyofthereactionweredetermined.Thelinearrangeis0.02–0.10lgáml-1,andthedetectionlimitis7.27910-4lgáml-1.ThismethodwasusedforthedeterminationofgadoliniuminthesamplesoflanthanumacetatewithRSDof0.9%–3.1%.

简介：Depositionoftwo-dimensional（2D）MoS2materialsonthetaperedfiberallowsvariousphotonicapplicationsincludingsaturableabsorbersandfour-wavemixing.Ethanolcatalyticdeposition（ECD）ofMoS2ontheopticaltaperedfiberwasproposedanddemonstratedinthiswork.Differentfromtheconventionalopticaldrivendepositionusingwaterororganicsolvent,theECDmethodutilizedthehighvolatilityoftheethanolsolvent,whichsignificantlyincreasedthemovementspeedoftheMoS2nanosheetsandthusboostedthedepositionrateandreducedtheminimumpowerthresholdtodrivethedeposition.WebelievetheECDmethodshouldbeabletobeappliedtoothersimilar2Dmaterialssuchasothertypesoftransitionmetalchalcogenides.

简介：

简介：

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.

简介：

简介：Perovskite-typeLa1-xCexMnO3（x=0-10%）catalystswerepreparedbyflamespraypyrolysisandtheiractivitiesduringthecatalyticoxidationofbenzenewereexaminedoverthetemperaturerangeof100-450℃.ThestructuralpropertiesandreducibilityofthesematerialswerealsocharacterizedbyX-raydiffraction（XRD）,N2adsorption/desorption,H2temperature-programmedreduction（H2-TPR）andX-rayphotoelectronspectroscopy（XPS）.TheincorporationofCewasfoundtoimprovethebenzeneoxidationactivity,andtheperovskiteinwhichxwas0.1exhibitedthehighestactivity.Phasecompositionandsurfaceelementalanalysesindicatedthatnon-stoichiometriccompoundswerepresent.TheincorporationofCehadanegligibleeffectonthespecificsurfaceareaoftheperovskitesandhencethisfactorhaslittleimpactonthecatalyticactivity.IntroductionofCe44+resultedinmodificationofthechemicalstatesofbothB-siteionsandoxygenspeciesandfacilitatedthereducibilityoftheperovskite.ThesurfaceMn4+/Mn3+ratiowasincreasedasaresultofCe4+substitution,whileadecreaseinthesurface-adsorbedO/latticeO(Oads/Olatt)ratiowasobserved.Therelationshipbetweenthesurfaceelementalratiosandcatalyticactivitywasestablishedtoallowabetterunderstandingoftheprocessbywhichbenzeneisoxidizedoverperovskites.

简介：Inthepresentwork,core-shellNi@SiO2catalystswereinvestigatedinordertoevaluatetherelevanceofcatalyticactivityandsurfacestatesofNicoreaswellasNinanoparticlessizetocatalyticpartialoxidationofmethane(POM).ThecatalystswerecharacterizedbyN2adsorption,H2-TPR,XRD,TEMandXPStechniques.Thecatalyticperformanceofthecore-shellcatalystswasfoundtobedependentonthesurfacestatesofcatalyst,whichinfluencedtheformationofproducts.Itwasconsideredthatcarbondioxideformedontheoxidizednickelsites(NiO)andcarbonmonoxideproducedonthereducedsites(Ni).ThesurfacestatesofactivemetalinthedynamicwereinfluencedbothbythesizeofNicoreandtheporosityofsilicashell.However,thecatalyticactivitywouldbedebasedwhenthesizeofNicorewasunderacertainextent,whichcanbeascribedtothefactthecarbondepositionincreasedwiththeincreasingcontentofNiO.TheeffectsofsurfacestatesofNi@SiO2catalystonthecatalyticperformancewerediscussedandthereactionpathwayoverNicoreencapsulatedinsidesilicashellwasproposed.