In this study,an efficient catalyst Ag@g-C_(3)N_(4) nanocomposite was successfully synthesized through a simple green reaction,and the characterizations through XRD,FTIR,SEM,BET and XPS were also studied.The activitie...In this study,an efficient catalyst Ag@g-C_(3)N_(4) nanocomposite was successfully synthesized through a simple green reaction,and the characterizations through XRD,FTIR,SEM,BET and XPS were also studied.The activities of Ag@g-C_(3)N_(4) were investigated toward the reduction of 4-nitrophenol to their corresponding aminophenol compounds in the presence of excess NaBH_(4) as a reducing agent.The Ag@g-C_(3)N_(4) nanocomposites exhibited high catalytic activities,in which a 92.2%4-nitrophenol conversion in 10 min and the apparent rate constant K_(app)=264.27×10^(-3) min-1were obtained.The as-prepared Ag@g-C_(3)N_(4) nanocomposites showed great potential in catalytically inducing the reduction of 4-nitrophenol,which makes them economically and energy conservation attractive from industrial waste water treatment.展开更多
In different synoptic conditions and at different time scales,the analysis of the energy budgets by Bowen Ratio Method and Bulk Schemes over Huaihe River Basin during the field observation periods of HUBEX in 1999 sho...In different synoptic conditions and at different time scales,the analysis of the energy budgets by Bowen Ratio Method and Bulk Schemes over Huaihe River Basin during the field observation periods of HUBEX in 1999 shows that,(1)the averaged latent heat flux is an order of magnitude more than the averaged sensible heat flux during the observation period:(2)the variation of total cloud amount is out of phase with the terms of energy budgets except for the downward longwave radiation which maybe is related to the cloud's height and class:(3)the values of sensible and latent heat fluxes are small during rain episodes,but thereafter,the values become high and then up to maximum.It is similar to the other terms of the energy budgets except for the downward longwave radiation.The diurnal variation of energy budgets indicates that the daytime precipitation exerts great influence to the energy budgets,but the nighttime precipitation makes little influence; (4)the variation of the latent heat flux is in phase with the evaporation,which indicates that the latent heat flux calculated by bulk schemes is reliable:(5)the means of the sensible and latent heat flux and momentum flux by bulk schemes for the time period from May to August are, respectively,30.71W/m^2.116.81W/m^2.2.86×10^(-2)N/m^2 in 1998 and 30.28W/m^2,107.35 W/m^2,2.74×10^(-2)N/m^2 in 1999.The values of these two years are similar.During summer in 1999 the magnitude and activity of sensible heat flux are strongest in June and those of the latent heat flux are in August.展开更多
In the summers of 1998 and 1999, Chinese and Japanese scientists cooperatively conducted the first large-scale energy and water cycle experiment(WCRP/GEWEX/GAME/HUBEX: World Climate Research Program/Global Energy and ...In the summers of 1998 and 1999, Chinese and Japanese scientists cooperatively conducted the first large-scale energy and water cycle experiment(WCRP/GEWEX/GAME/HUBEX: World Climate Research Program/Global Energy and Water Cycle Experiment/Asian Monsoon Experiment/Huaihe River Basin Energy and Water Cycle Experiment) in the Huaihe River basin, Anhui Province of China. The main objective of this field experiment(HUBEX)was to investigate the multiple-scale structure characteristics, life cycles, and genesis and development mechanisms of the Meiyu system in East Asia as well as the cause of related flooding disasters. It was a joint China-Japan cooperative meteorological and hydrological observation experiment. On the basis of intensive observations, scientists from the two countries conducted follow-up investigations through collating and compiling data and performing scientific analysis during the following five years. It can be concluded that the HUBEX project has yielded comprehensive and remarkable achievements. This paper introduces the major scientific results derived from this field experiment and the ensuing investigations, and reassesses their merits and shortages for the purpose of providing useful experience and proposing new research targets as well as prospects for the initiation of a new joint scientific Meiyu experiment in the middle and lower Yangtze River basin.展开更多
基金Project supported by the Natural Science Foundation of Fujian Province(No.2019J01747 and 2020J01803)Fujian Provincial Key Laboratory of Featured Materials in Biochemical Industry(FJKLFBCM202104)China NSF(No.41976150)。
文摘In this study,an efficient catalyst Ag@g-C_(3)N_(4) nanocomposite was successfully synthesized through a simple green reaction,and the characterizations through XRD,FTIR,SEM,BET and XPS were also studied.The activities of Ag@g-C_(3)N_(4) were investigated toward the reduction of 4-nitrophenol to their corresponding aminophenol compounds in the presence of excess NaBH_(4) as a reducing agent.The Ag@g-C_(3)N_(4) nanocomposites exhibited high catalytic activities,in which a 92.2%4-nitrophenol conversion in 10 min and the apparent rate constant K_(app)=264.27×10^(-3) min-1were obtained.The as-prepared Ag@g-C_(3)N_(4) nanocomposites showed great potential in catalytically inducing the reduction of 4-nitrophenol,which makes them economically and energy conservation attractive from industrial waste water treatment.
基金the National Natural Science Foundation of China(No.49794030).
文摘In different synoptic conditions and at different time scales,the analysis of the energy budgets by Bowen Ratio Method and Bulk Schemes over Huaihe River Basin during the field observation periods of HUBEX in 1999 shows that,(1)the averaged latent heat flux is an order of magnitude more than the averaged sensible heat flux during the observation period:(2)the variation of total cloud amount is out of phase with the terms of energy budgets except for the downward longwave radiation which maybe is related to the cloud's height and class:(3)the values of sensible and latent heat fluxes are small during rain episodes,but thereafter,the values become high and then up to maximum.It is similar to the other terms of the energy budgets except for the downward longwave radiation.The diurnal variation of energy budgets indicates that the daytime precipitation exerts great influence to the energy budgets,but the nighttime precipitation makes little influence; (4)the variation of the latent heat flux is in phase with the evaporation,which indicates that the latent heat flux calculated by bulk schemes is reliable:(5)the means of the sensible and latent heat flux and momentum flux by bulk schemes for the time period from May to August are, respectively,30.71W/m^2.116.81W/m^2.2.86×10^(-2)N/m^2 in 1998 and 30.28W/m^2,107.35 W/m^2,2.74×10^(-2)N/m^2 in 1999.The values of these two years are similar.During summer in 1999 the magnitude and activity of sensible heat flux are strongest in June and those of the latent heat flux are in August.
基金Supported by the Special Strategic Project of Leading Science and Technology of Chinese Academy of Sciences(XDA20100304)National Natural Science Foundation of China(41790471)。
文摘In the summers of 1998 and 1999, Chinese and Japanese scientists cooperatively conducted the first large-scale energy and water cycle experiment(WCRP/GEWEX/GAME/HUBEX: World Climate Research Program/Global Energy and Water Cycle Experiment/Asian Monsoon Experiment/Huaihe River Basin Energy and Water Cycle Experiment) in the Huaihe River basin, Anhui Province of China. The main objective of this field experiment(HUBEX)was to investigate the multiple-scale structure characteristics, life cycles, and genesis and development mechanisms of the Meiyu system in East Asia as well as the cause of related flooding disasters. It was a joint China-Japan cooperative meteorological and hydrological observation experiment. On the basis of intensive observations, scientists from the two countries conducted follow-up investigations through collating and compiling data and performing scientific analysis during the following five years. It can be concluded that the HUBEX project has yielded comprehensive and remarkable achievements. This paper introduces the major scientific results derived from this field experiment and the ensuing investigations, and reassesses their merits and shortages for the purpose of providing useful experience and proposing new research targets as well as prospects for the initiation of a new joint scientific Meiyu experiment in the middle and lower Yangtze River basin.