简介：γ－ｒａｙ　ｉｎ　２５　ＭｅＶ／ｕ　４０Ａｒ＋１１５Ｉｎ　ａｎｄ　１０３Ｒｈ　Ｆｕｓｉｏｎ－ｆｉｓｓｉｏｎ　Ｒｅａｃｔｉｏｎｓγ－ｒａｙｉｎ２５ＭｅＶ／ｕ４０Ａｒ＋１１５Ｉｎａｎｄ１０３ＲｈＦｕｓｉｏｎ－ｆｉｓｓｉｏｎＲ...

简介：Rhodium-andironphosphate-basedcatalystsarebyfarthemostpromisingcatalystsforoxy-brominationofmethane(OBM)reaction.However,mostliteraturereportedeitherRh-orFePO4-basedcatalysts,andtheresultswererarelystudiedinauniformenvironmentalcondition.Inthisreport,comparativestudywasconductedonsilica-andsiliconcarbide-supportedrhodiumandironphosphatecatalystswiththemainfocusesonstabilityperformanceandcokedeposition.ThecatalyticresultsdemonstratedthatthestabilityofbothRh-andFePO4-basedcatalystswasgreatlyinfluencedbythesupportsused,andsiliconcarbide-supportedcatalystsshowedmuchbetteranti-cokingabilityascomparedwithsilica-supportedones.Temperature-programmedoxidationovertheusedcatalystsfurtherindicatedthatthecokeformationmechanismswerecompletelydifferentbetweensilica-supportedrhodiumandironphosphatecatalysts.WhilecokesmightbecausedbycondensationofCH2Br2oversupportedironphosphate,methanedecompositionmightbethereasonforcokeformationoversilica-supportedrhodiumcatalyst.ThesefindingsmightpavethewayfordesigninghighlyefficientandstablecatalystsoftheOBMreaction.

简介：ThesplittingofpotentialenergylevelsforgroundstateX2ΠgofOx2(x=+1,1)underspin–orbitcoupling(SOC)hasbeencalculatedbyusingthespin–orbit(SO)multi-configurationquasi-degenerateperturbationtheory(SO-MCQDPT).TheirMurrell–Sorbie(M–S)potentialfunctionsaregained,andthenthespectroscopicconstantsforelectronicstates2Π1/2and2Π3/2arederivedfromtheM–Sfunction.TheverticalexcitationenergiesforOx2(x=+1,1)areν[O+12(2Π3/2→X2Π1/2)]=195.652cm1,andν[O12(2Π1/2→X2Π3/2)]=182.568cm1,respectively.Allthespectroscopicdataforelectronicstates2Π1/2and2Π3/2aregivenforthefirsttime.

简介：Ｔｈｒｅｅｆｏｌｄ　Ｆｒａｇｍｅｎｔａｔｉｏｎ　ｏｆ　Ｈｏｔ　Ｃｏｍｐｏｕｎｄ　Ｎｕｃｌｅｉ　ｉｎ　２５　ＭｅＶ／ｕ４０Ａｒ＋１１５Ｉｎ，　１０３Ｒｈ　ａｎｄ　９３Ｎｂ　ＲｅａｃｔｉｏｎｓＴｈｒｅｅｆｏｌｄＦｒａｇｍｅｎｔａｔｉｏ...

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简介：1．大肥猪的质量约为150kg，其体重约为________N，相一当于__________个质量为25kg的狗的体重．

简介：当堂反馈1．压强是反映——的物理量．一辆“东风牌”汽车对地面的压强是1．8×10^4Pa它所表示的物理含义是——.

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.

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简介：Inthisarticle,theSm-dopingsinglecrystalsCa1-xSmxFe2As2（x=00.2）werepreparedbytheCaAsfluxmethod,andfollowedbyarapidquenchingtreatmentafterthehightemperaturegrowth.Thesampleswerecharacterizedbystructural,resistive,andmagneticmeasurements.ThesuccessfulSm-substitutionwasrevealedbythereductionofthelatticeparameterc,duetothesmallerionicradiusofSm3+thanCa2+.SuperconductivitywasobservedinallsampleswithonsetTcvaryingfrom27Kto44KuponSm-doping.ThecoexistenceofacollapsedphasetransitionandthesuperconductingtransitionwasfoundforthelowerSm-dopingsamples.ZeroresistivityandsubstantialsuperconductingvolumefractiononlyhappeninhigherSm-dopingcrystalswiththenominalx>0.10.Thedopingdependencesofthec-axislengthandonsetTcweresummarized.Thehigh-TcobservedinthesequenchedcrystalsmaybeattributedtosimultaneoustuningofelectroncarriersdopingandstraineffectcausedbylatticereductionofSm-substitution.

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简介：Theground-stateandthermodynamicpropertiesofquantummixed-spinchainsof1/2-1/2-1-1and3/2-3/2-1-1areinvestigatedbyaquantumMonteCarlosimulationwiththeloop-clusteralgorithm.For1/2-1/2-1-1chain,wefindithastwophasesseparatedbyanenergy-gapvanishingpointintheground-state.For3/2-3/2-1-1chain,thenumericalresultsshowtwoenergy-gapvanishingpointsisolatedbydifferentphasesinitsground-state.Ourcalculationsindicatethatallthesegroundstatephasescanbeunderstoodbymeansofvalence-bond-solidpicture,andthethermodynamicbehavioratfinitetemperaturesiscontinuousasafunctionofparameterα=J2/J1.

简介：Thedipole-length,velocityandaecelerationabsorptionoscillatorstrengthsforthe1s^22p-ls^2nd(3_2=11to20arecalculatedusingtheenergiesandthemulticonfiguratloninteractionwavefunctionsobtainedfromafullcorepluscorrelationmethod.Theagreementbetweenthef-valuescalculatedfromthelength,velocityandaccelerationformulaeisexcellent.Ourresultsagreecloselywiththeexperimentaldataavailableintheliterature.Combiningthesediscreteoscillatorstrengthswiththesingle-channelquantumdefecttheory,thediscreteoscillatorstrengthsforthetransitionsfrom1s^22pstatetohighlyexcitedstates(n_>10)andtheoscillatorstrengthdensitiescorrespondingtothebound-freetransitionsareobtained.

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