The problems of flooding, bank erosion and even the breaching of the barrier beach by the Grand-Popo lagoon are a concern in the south-western Beninese river-lagoon complex. The present study aims to improve the knowl...The problems of flooding, bank erosion and even the breaching of the barrier beach by the Grand-Popo lagoon are a concern in the south-western Beninese river-lagoon complex. The present study aims to improve the knowledge of the factors controlling the hydro-sedimentary functioning of this lagoon of Grand-Popo. It was based on bathymetric and sedimentological studies and the analysis of physical-chemical parameters of the water and allowed to know the morphology of the lagoon bottom and the distribution of sedimentary facies according to the intensity of the water current. The salinity of the lagoon waters shows a west-east gradient passing thus from 0‰ to 0.78‰ in the main direction of flow. Over the whole lagoon system, the average liquid flows vary from <span style="color:#4F4F4F;font-family:-apple-system, "font-size:16px;white-space:normal;background-color:#FFFFFF;">-</span>38.499 to 159.13 m<sup>3</sup>/s. The bathymetry indicates depths varying from 0.4 to 6.5 m, revealing type V and type U lagoon bottoms which reflect acute bottom concavities marked by hollowing under the effect of strong currents or by sandy terraces resulting from the continuous input of sediments carried by the Mono River. These sediments are heterogeneously distributed in the lagoon bottom and vary from free sand to mud. Given the complexity of the factors that control the hydro-sedimentary functioning of the Grand-Popo lagoon, it is recommended that periodic hydrological and bathymetric monitoring be carried out to locate exceptional variations in water levels to prevent not only the risks of overflowing lagoon waters and the flooding that follows but also spectacular erosion of the lagoon banks.展开更多
The high efficient blowing technique includes increasing oxygen supply intensity and optimizing slag forming. The oxygen supply intensity on 300 t converters of No. 1 steelmaking shop at Baosteel reaches 3.83 m^3/（t ...The high efficient blowing technique includes increasing oxygen supply intensity and optimizing slag forming. The oxygen supply intensity on 300 t converters of No. 1 steelmaking shop at Baosteel reaches 3.83 m^3/（t · min）, and at Taiyuan Steel, Lianyuan Steel, Pingxiang Steel and other steel plants, the oxygen supply intensity on medium converters is in the range of 4.0--4.4m^3/（t · min）. The productivity of converter can be increased by 8% -- 15% with adopting this technique. The whole technique, including design and manufacture of lance nozzle with reasonable pacnolontenue of outlets, technique of oxygen supply and slag forming, has been developed by CISRI to meet the need of technique transfer.展开更多
Holding a dominant position in the spatial planning system at the city level, a city master plan should be able to guide both long-term strategies and short-term planning implementation, while taking into account both...Holding a dominant position in the spatial planning system at the city level, a city master plan should be able to guide both long-term strategies and short-term planning implementation, while taking into account both resource conservation and urban-rural development and coordinating multi-government power and interests of various stakeholders. In the future, city master planning should keep its advanced nature and must follow the principles of being people-oriented, paying equal attention to both development quality and quantity, promoting diversified development, and containing multiple driving forces for development.展开更多
文摘The problems of flooding, bank erosion and even the breaching of the barrier beach by the Grand-Popo lagoon are a concern in the south-western Beninese river-lagoon complex. The present study aims to improve the knowledge of the factors controlling the hydro-sedimentary functioning of this lagoon of Grand-Popo. It was based on bathymetric and sedimentological studies and the analysis of physical-chemical parameters of the water and allowed to know the morphology of the lagoon bottom and the distribution of sedimentary facies according to the intensity of the water current. The salinity of the lagoon waters shows a west-east gradient passing thus from 0‰ to 0.78‰ in the main direction of flow. Over the whole lagoon system, the average liquid flows vary from <span style="color:#4F4F4F;font-family:-apple-system, "font-size:16px;white-space:normal;background-color:#FFFFFF;">-</span>38.499 to 159.13 m<sup>3</sup>/s. The bathymetry indicates depths varying from 0.4 to 6.5 m, revealing type V and type U lagoon bottoms which reflect acute bottom concavities marked by hollowing under the effect of strong currents or by sandy terraces resulting from the continuous input of sediments carried by the Mono River. These sediments are heterogeneously distributed in the lagoon bottom and vary from free sand to mud. Given the complexity of the factors that control the hydro-sedimentary functioning of the Grand-Popo lagoon, it is recommended that periodic hydrological and bathymetric monitoring be carried out to locate exceptional variations in water levels to prevent not only the risks of overflowing lagoon waters and the flooding that follows but also spectacular erosion of the lagoon banks.
文摘The high efficient blowing technique includes increasing oxygen supply intensity and optimizing slag forming. The oxygen supply intensity on 300 t converters of No. 1 steelmaking shop at Baosteel reaches 3.83 m^3/（t · min）, and at Taiyuan Steel, Lianyuan Steel, Pingxiang Steel and other steel plants, the oxygen supply intensity on medium converters is in the range of 4.0--4.4m^3/（t · min）. The productivity of converter can be increased by 8% -- 15% with adopting this technique. The whole technique, including design and manufacture of lance nozzle with reasonable pacnolontenue of outlets, technique of oxygen supply and slag forming, has been developed by CISRI to meet the need of technique transfer.
文摘Holding a dominant position in the spatial planning system at the city level, a city master plan should be able to guide both long-term strategies and short-term planning implementation, while taking into account both resource conservation and urban-rural development and coordinating multi-government power and interests of various stakeholders. In the future, city master planning should keep its advanced nature and must follow the principles of being people-oriented, paying equal attention to both development quality and quantity, promoting diversified development, and containing multiple driving forces for development.
