采用模板法,以SiO2为模板,盐酸多巴胺(PDA)为碳源,通过SiO2构筑具有高度连通的三维多孔结构的氮掺杂中空介孔碳纳米材料(NMHCS),然后以NMHCS为载体,通过简单的预沉淀法将钌负载在碳球表面,制备具有钌负载的氮掺杂中空介孔碳纳米材料电...采用模板法,以SiO2为模板,盐酸多巴胺(PDA)为碳源,通过SiO2构筑具有高度连通的三维多孔结构的氮掺杂中空介孔碳纳米材料(NMHCS),然后以NMHCS为载体,通过简单的预沉淀法将钌负载在碳球表面,制备具有钌负载的氮掺杂中空介孔碳纳米材料电催化剂(Ru/NMHCS),并利用氧气进一步氧化得到Ru/RuO2异质结构电催化剂材料。该异质结构的纳米催化剂材料对析氧反应(OER)表现出显著的电催化活性,电流密度在10 m A·cm^(-2)处的过电位为270 mV,明显优于基准贵金属催化剂RuO2。为贵金属电催化剂的制备提供实验技术参考。展开更多
Studies of the flow and sediment movement in a cavity with free surface were mostly limited to physical modeling experiments. In this study, the sediment movement is characterized in detail using a 3-D turbulent numer...Studies of the flow and sediment movement in a cavity with free surface were mostly limited to physical modeling experiments. In this study, the sediment movement is characterized in detail using a 3-D turbulent numerical model. To close the Reynolds equations, the standard k-ε model is employed. The VOF method is adopted to capture the time varying free surface and the porosity method is introduced to deal with the irregular boundary and the varying bed deformation. The computation results agree well with the experimental data in major aspects such as the vertical distribution of the sediment concentration and the deposition topography in the cavity. The comparisons show that this model can well predict the flow structure and the sediment movement and also the river bed deformation in a cavity.展开更多
Three 2-{(3R,7aS)-1,1-disubstituted-tetrahydro-1H-pyrrolo[1,2-c][1,3]oxazol-3-yl}phenols have been synthesized from salicylaldehyde and amino alcohols derived from L-proline,and used as ligands hi enantioselective add...Three 2-{(3R,7aS)-1,1-disubstituted-tetrahydro-1H-pyrrolo[1,2-c][1,3]oxazol-3-yl}phenols have been synthesized from salicylaldehyde and amino alcohols derived from L-proline,and used as ligands hi enantioselective addition of diethylzinc to aldehydes,the ee values of obtained secondary alcohols were found in the range of 0-90%.展开更多
文摘采用模板法,以SiO2为模板,盐酸多巴胺(PDA)为碳源,通过SiO2构筑具有高度连通的三维多孔结构的氮掺杂中空介孔碳纳米材料(NMHCS),然后以NMHCS为载体,通过简单的预沉淀法将钌负载在碳球表面,制备具有钌负载的氮掺杂中空介孔碳纳米材料电催化剂(Ru/NMHCS),并利用氧气进一步氧化得到Ru/RuO2异质结构电催化剂材料。该异质结构的纳米催化剂材料对析氧反应(OER)表现出显著的电催化活性,电流密度在10 m A·cm^(-2)处的过电位为270 mV,明显优于基准贵金属催化剂RuO2。为贵金属电催化剂的制备提供实验技术参考。
基金Project supported by the National Natural Science Foundation of China (Grant No. 51079104)supported by the Ph. D. Independent Research Fund of Wuhan University (Grant No. 20102060101000064)
文摘Studies of the flow and sediment movement in a cavity with free surface were mostly limited to physical modeling experiments. In this study, the sediment movement is characterized in detail using a 3-D turbulent numerical model. To close the Reynolds equations, the standard k-ε model is employed. The VOF method is adopted to capture the time varying free surface and the porosity method is introduced to deal with the irregular boundary and the varying bed deformation. The computation results agree well with the experimental data in major aspects such as the vertical distribution of the sediment concentration and the deposition topography in the cavity. The comparisons show that this model can well predict the flow structure and the sediment movement and also the river bed deformation in a cavity.
基金Project supported by the Key Laboratory of Organic Syntheses,Jiangsu Province(No.T2109102).
文摘Three 2-{(3R,7aS)-1,1-disubstituted-tetrahydro-1H-pyrrolo[1,2-c][1,3]oxazol-3-yl}phenols have been synthesized from salicylaldehyde and amino alcohols derived from L-proline,and used as ligands hi enantioselective addition of diethylzinc to aldehydes,the ee values of obtained secondary alcohols were found in the range of 0-90%.
