简介:Highspinstatesintheodd-oddnucleus124Cshavebeeninvestigatedthroughthefusion-evaporationreaction116Sn(11B,3n)124Cswithabeamenergyof45MeV.Anewrotationalbandisestablishedandassignedasthehigh-kconfigurationofπg9/2[404]9/2+νh11/2[523]7/2.Somestructureslinkingtothisbandhavealsobeenobserved.Accordingtotheresultsoftheexcitationenergysystematics,thelowestlevelofthisbandisassignedas9,andthe8isomerbandheadhasnotbeenobserved.Anotherisomerwithahalflifeof6.3shasalsobeenobservedwithitsnewdecaypathsestablished.Itsexcitationenergyisraisedby79keV,butitsIπisnotchanged.
简介:AseriesofoxideizedCO-K-Mo/γ-Al2O3catalystsamples,preparedbyimpregnatingoxidizedK-Mo/γ-Al2O3sampleswithanaqueoussolutionofcalculatedCo(NO3)2andthencalcininginairattemperaturesof350℃,500℃65℃and800℃respectively,weresulfidedandtheninvestigatedfortheactivityinthesynthesisofmixedalcoholsfromCOhydrogenationunderconditionsofp=5.0MPa,T=350℃andGHSV=4800h^-1.TheresultsdemonstratethattheadditionofcobaltpromoterisfavorabletotheformationofhigheralcoholsandtheopimumcalcinationtemperaturesafterimpregnatingwithCo^2+areabout500-650℃.ThestructureofCoandMospeciesontheoxidizedandsulfidedsampleswasdeterminedbyX-raydiffraction(XRD),laserRamanspectrum(LRS)andextendedX-rayabsorptionfinestructure(EXAFS).Foroxidizedsamplecalcinedat350℃,cobaltexistsasCo3O4spectiesandcoversthesurfaceofK-Mo-Ospecies,thestructureofK-Mo-OspeciesisthesameasthatinK-Mo/Al2O3sample.TheinteractionbetweencobaltandK-Mo-Ospeciesisrelativelyweak.Aftersulfidation.Cobaltexistsassulfidecrystalliteswithanoctahedralcoordinatedstructure,andmolybdenumasMoS2crystallites.Foroxidizedsamplescalcinedat500-650℃,CocomponentinteractswiththeK-Mo-Ospeciesanddestroysthelong-rangeorderoftheK-Mo-Ospectesgradually,Aftersulfidation.CotendstoexistasasulfidewithtetrahedralcoordinatedstructureandMostillasMoS2crystallites.Foroxidizedsamplecalcinedat800℃,CocomponentexistsmainlyasCoAl2O4species,mostofwhichcannotbesultidedduringsulfidation.
简介:Oneofthetechnicalbottlenecksoftraditionallaser-inducedbreakdownspectroscopy(LIBS)isthedifficultyinquantitativedetectioncausedbythematrixeffect.Totroubleshootthisproblem,thispaperinvestigatedacombinationoftime-resolvedLIBSandconvolutionalneuralnetworks(CNNs)toimproveKdeterminationinsoil.Thetime-resolvedLIBScontainedtheinformationofbothwavelengthandtimedimension.Thespectraofwavelengthdimensionshowedthecharacteristicemissionlinesofelements,andthoseoftimedimensionpresentedtheplasmadecaytrend.Theone-dimensionaldataofLIBSintensityfromtheemissionlineat766.49nmwereextractedandcorrelatedwiththeKconcentration,showingapoorcorrelationofR^2c=0.0967,whichiscausedbythematrixeffectofheterogeneoussoil.Forthewavelengthdimension,thetwo-dimensionaldataoftraditionalintegratedLIBSwereextractedandanalyzedbyanartificialneuralnetwork(ANN),showingR^2v=0.6318andtherootmeansquareerrorofvalidation(RMSEV)=0.6234.Forthetimedimension,thetwo-dimensionaldataoftime-decayLIBSwereextractedandanalyzedbyANN,showingR^2v=0.7366andRMSEV=0.7855.Thesehigherdeterminationcoefficientsrevealthatboththenon-KemissionlinesofwavelengthdimensionandthespectraldecayoftimedimensioncouldassistinquantitativedetectionofK.However,duetolimitedcalibrationsamples,thetwo-dimensionalmodelspresentedover-fitting.Thethree-dimensionaldataoftime-resolvedLIBSwereanalyzedbyCNNs,whichextractedandintegratedtheinformationofboththewavelengthandtimedimension,showingtheR^2v=0.9968andRMSEV=0.0785.CNNanalysisoftime-resolvedLIBSiscapableofimprovingthedeterminationofKinsoil.