The nitrogen and sulfur co-doped carbon dots(N, S-CDs) with increased luminescence were synthesized by a hydrothermal process in one green pot by using glucose, and a new sulfur-doping source of sodium sulfite was dev...The nitrogen and sulfur co-doped carbon dots(N, S-CDs) with increased luminescence were synthesized by a hydrothermal process in one green pot by using glucose, and a new sulfur-doping source of sodium sulfite was developed.The synergistic effect of the N and S groups was well discussed through the structure analysis of Fourier transform infrared spectra and x-ray photoelectron spectra. The surface states of N, S-CDs embody more complicated functional groups, and S element exists as –SSO3, –C–SO3, and SO-42groups due to the introduction of sodium sulfite. The sulfur-containing groups passivate the surface of the CDs, and the relatively high sulfur groups may reduce the non-radiation centers. The fluorescence is affected by the hydroxyl group of the solvent. The quenching of Fe3+ ion to fluorescence and the sensitivity of fluorescence to p H were also investigated.展开更多
Previous studies have indicated that the peak of the quarkonium entropy at the deconfinement transition can be related to the entropic force,which would induce the dissociation of heavy quarkonium.In this study,we inv...Previous studies have indicated that the peak of the quarkonium entropy at the deconfinement transition can be related to the entropic force,which would induce the dissociation of heavy quarkonium.In this study,we investigated the entropic force in a rotating hot and dense medium using AdS/CFT correspondence.It was found that the inclusion of angular velocity increases the entropic force,thus enhancing quarkonium dissociation,while chemical potential has the same effect.The results imply that the quarkonium dissociates easier in rotating medium compared with the static case.展开更多
基金Project by the National Natural Science Foundation of China(Grant Nos.51571085,11805052,and 61705062)the Research Project for Basic and Forefront Technology of Henan Province,China(Grant No.162300410219)the Doctor Foundation of Henan Polytechnic University,China(Grant No.B2014049)
文摘The nitrogen and sulfur co-doped carbon dots(N, S-CDs) with increased luminescence were synthesized by a hydrothermal process in one green pot by using glucose, and a new sulfur-doping source of sodium sulfite was developed.The synergistic effect of the N and S groups was well discussed through the structure analysis of Fourier transform infrared spectra and x-ray photoelectron spectra. The surface states of N, S-CDs embody more complicated functional groups, and S element exists as –SSO3, –C–SO3, and SO-42groups due to the introduction of sodium sulfite. The sulfur-containing groups passivate the surface of the CDs, and the relatively high sulfur groups may reduce the non-radiation centers. The fluorescence is affected by the hydroxyl group of the solvent. The quenching of Fe3+ ion to fluorescence and the sensitivity of fluorescence to p H were also investigated.
文摘Previous studies have indicated that the peak of the quarkonium entropy at the deconfinement transition can be related to the entropic force,which would induce the dissociation of heavy quarkonium.In this study,we investigated the entropic force in a rotating hot and dense medium using AdS/CFT correspondence.It was found that the inclusion of angular velocity increases the entropic force,thus enhancing quarkonium dissociation,while chemical potential has the same effect.The results imply that the quarkonium dissociates easier in rotating medium compared with the static case.
