简介：Theeffectoftheimprovementofcommercialactivatedcarbon(AC)onitsspecificcapacitanceandhighratecapabilityofdoublelayer(dl)charging/dischargingprocesshasbeenstudied.TheimprovementofACwascarriedoutviaasecondaryactivationundersteaminthepresenceofcatalystNiCl2,andthesuitableconditionwasfoundtobeaheattreatmentatabout875℃for1h.Underthoseconditions,thedischargespecificcapacitanceoftheimprovedACincreasesupto53.67F/g,showinganincreaseofabout25%ascomparedwiththatofas-receivedAC.Thegoodrectangular-shapedvoltammogramsandA.C.impedancespectraprovethatthehighratecapabilityofthecapacitormadeoftheimprovedACisenhancedsignificantly.Thecapacitanceresistance(RC)timeconstantofthecapacitorcontainingtheimprovedACis1.74s,whichismuchlowerthanthatoftheonecontainingas-receivedAC(anRCvalueof4.73s).ItisnotedthatbothkindsofACsamplesshowasimilarspecificsurfaceareaandporesizedistribution,butsomechangeshavetakenplaceinthecarbonsurfacegroups,especiallyadecreaseintheconcentrationofsurfacecarbonylgroupsaftertheimprovement,whichhavebeenverifiedbymeansofX-photoelectronspectroscopy.Accordingly,itissuggestedthatthedecreaseintheconcentrationofsurfacecarbonylgroupsfortheimprovedACisbeneficialtotheorganicelectrolyteionpenetratingintothepores,thusleadingtotheincreaseinboththespecificcapacitanceandhighratecapabilityofthesupercapacitor.

简介：Secondaryalcoholswerecatalyticallyoxidizedwithdiace-toxyiodobenzeneasoxidantinthepresenceofsalen-Mn(Ⅲ)complextoaiTordtheeorrespoltdingketones,inupto99%yield,usingCH2Cl2orwaterasreactionmedia.

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