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由于对环境影响的关注,日本福岛核电站事故后,人们进行了大气、陆地和海洋环境人工放射性核素变化监测与研究,研究的主要核素是131I、137 Cs、134 Cs和129I。除了关注浓度水平的变化外,还进行了通过大气和海流对事故释放的放射性核素运行路径的模拟研究。研究表明,受气候条件的控制,事故释放进入大气的放射性核素先经过太平洋到达北美,然后越过大西洋到达欧洲,最后绕北半球一周后到达中国。除事故核电站周边外,全球大气中131I活度浓度在mBq/m3量级,137 Cs活度浓度在0.1~1mBq/m3量级。事故释放进入海洋的放射性核素将随海流向东输运,然后在北太平洋随环流输运。研究也发现在离开源地不远的海区,由于混合进入200m水深以下的次表层水,在远离事故核电站海区水体的137 Cs活度浓度可达100Bq/m3,但大部分水体137 Cs活度浓度在Bq/m3量级,仅稍高于本底水平。
Due to environmental concerns, man-made radionuclide changes in the air, land and marine environment were monitored and studied after the Fukushima nuclear accident in Japan. The main radionuclides studied were 131I, 137Cs, 134Cs and 129I. In addition to focusing on changes in concentration levels, a simulation study of the radionuclide travel path through the atmosphere and ocean currents to accidents was also conducted. Research shows that controlled by climatic conditions, the accidental release of radionuclides into the atmosphere first reaches North America through the Pacific Ocean, then across the Atlantic Ocean to Europe and finally to China in the northern hemisphere a week later. In addition to the accident nuclear power plant periphery, the global atmosphere 131I activity concentration in the mBq / m3 order, 137 Cs activity concentration in the order of 0.1 ~ 1mBq / m3. The radionuclides released into the ocean by accident will be transported eastward along with the currents and then circulate in the North Pacific. The study also found that in the sea area not far away from the source, the concentration of 137 Cs in water far away from the accidental nuclear power plant can reach 100Bq / m3 due to the sub-surface water mixed into the water below 200m depth, but most 137Cs activity concentrations At Bq / m3, only slightly above background.