简介：Carbonsurfacewithlargeoxygenandcarbonratio(O/C)indicatedanoutstandingelectro-catalyticactivitytowardL-ascorbicacidoxidation,comparedtoplatinumgroupmetals.However,interrelationofsurfacefunctionalgroupsanditselectro-catalyticactivityisstillunclear.Inthispaper,weprepareddifferentlevelsofoxidizedcarbonsbyasimpleacidtreatmentandinvestigatedthecorrelationbetweenthesurfaceoxygenfunctionalgroupsofacid-treatedcarbonandelectro-catalyticactivityinanelectrooxidationofL-ascorbicacid.Positivelychargedcarbonwasdemonstratedbylonepairelectronofoxygenfromvalencebandspectrastudy.Itwasrevealedthatthepositivelychargedcarbon,especiallyinvolvedincarbonyl,showedenhancedtheelectro-catalyticactivitythroughbothbetteradsorptionofnegativelychargedreactantsandloweredLUMObyelectronegativityofoxygen.

简介：Usingasimpletwo-parameterwavefunction,wecalculatevariationallythebindingenergyofpositivelyandnegativelychargedexcitonsinGaAs/AlxGa1-xAsquantumwellsforwellwidthsfrom10to300A.Weconsidertheeffectofeffectivemass,dielectricconstantmismatchinthetwomaterials,andthewholecorrelationamongtheparticles.Theresultsarediscussedandcomparedindetailwithpreviousexperimentalandtheoreticalresults,whichshowfairagreementwiththem.