Since its founding in 1949,the Chinese Academy of Sciences (CAS) has committed itself to gaining honor for our nation by successfully scaling heights of contemporary science.To this end.Chinese scientists have striven...Since its founding in 1949,the Chinese Academy of Sciences (CAS) has committed itself to gaining honor for our nation by successfully scaling heights of contemporary science.To this end.Chinese scientists have striven to exert themselves from generation to generation in a courageous and unflagging way. During the period of the national Eighth Five-year Plan(1991—1995), the scientists with the CAS went on working at the frontiers of international science.According to statistics,there were 205 key R&D projects展开更多
Based on the monitoring data of water quality of more than 40 centralized drinking water sources in 40 towns （townships or streets） of Kaixian County in the first and second half of each year during the ＂Twelfth Fi...Based on the monitoring data of water quality of more than 40 centralized drinking water sources in 40 towns （townships or streets） of Kaixian County in the first and second half of each year during the ＂Twelfth Five-year Plan＂ period, the changing rules of the water quality were studied to provide scientific references for the improvement of drinking water safety of urban and rural residents and drinking water quality. The re- sults show that the water quality of centralized drinking water sources in Kaixian County improved year by year during the ＂Twelfth Five-year Plan＂ period, and most monitoring sites with water quality exceeding the standard are distributed in reservoirs. Total phosphorus, total nitrogen, chemical oxygen demand, and permanganate index exceeded the standard obviously. Main pollution sources are domestic pollution and non-point source pol- lution caused by excessive discharge of nitrogen, phosphorus and organic pollutants. To improve drinking water quality, it is suggested that some towns can get drinking water from other reservoirs, surface water or underground water with better quality instead of previous reservoirs with water quality exceeding the standard, and the control of non-point source pollution should be enhanced.展开更多
文摘Since its founding in 1949,the Chinese Academy of Sciences (CAS) has committed itself to gaining honor for our nation by successfully scaling heights of contemporary science.To this end.Chinese scientists have striven to exert themselves from generation to generation in a courageous and unflagging way. During the period of the national Eighth Five-year Plan(1991—1995), the scientists with the CAS went on working at the frontiers of international science.According to statistics,there were 205 key R&D projects
文摘Based on the monitoring data of water quality of more than 40 centralized drinking water sources in 40 towns （townships or streets） of Kaixian County in the first and second half of each year during the ＂Twelfth Five-year Plan＂ period, the changing rules of the water quality were studied to provide scientific references for the improvement of drinking water safety of urban and rural residents and drinking water quality. The re- sults show that the water quality of centralized drinking water sources in Kaixian County improved year by year during the ＂Twelfth Five-year Plan＂ period, and most monitoring sites with water quality exceeding the standard are distributed in reservoirs. Total phosphorus, total nitrogen, chemical oxygen demand, and permanganate index exceeded the standard obviously. Main pollution sources are domestic pollution and non-point source pol- lution caused by excessive discharge of nitrogen, phosphorus and organic pollutants. To improve drinking water quality, it is suggested that some towns can get drinking water from other reservoirs, surface water or underground water with better quality instead of previous reservoirs with water quality exceeding the standard, and the control of non-point source pollution should be enhanced.
