Artificial radionuclides in the western Northwest Pacific (II):137Cs and239,240Pu inventories in water and sediment columns observed from 1980 to 1986
Artificial radionuclides in the western Northwest Pacific (II):137Cs and239,240Pu inventories in water and sediment columns observed from 1980 to 1986
复制标题
西北太平洋西部人工放射性核素(II)：1980年至1986年观测到的水和沉积物柱中的137Cs和239,240Pu库存
DOI：
10.1007/bf02109287
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发表时间：
1987
期刊：
影响因子：
--
通讯作者：
K. Nakamura
中科院分区：
文献类型：
--
作者：
Y. Nagaya;K. Nakamura
1980 - 1986年，在北太平洋西部沃茨和沉积物柱中测定了137 Cs和239，240 Pu的浓度和总量。但在沉积物中的比值范围很窄（10−2到10−1），这表明从水柱中去除钚比去除137 Cs更有效。在北纬40度以南的区域，水柱中的放射性核素存量大大超过估计的全球沉降物（大气核爆炸造成的平流层沉降物），特别是239，240钚。这些过剩的库存量意味着，尽管大气层核爆炸暂停已有约20年，但赤道北太平洋核爆炸产生的局部或近距离沉降物在这些区域得到了良好的保存和保留。结果表明，137 Cs在40 ° N以北的表层水中向南部地区的横向输送。文中还提供了有关~（90）Sr含量的一些数据。
Concentrations and inventories of137Cs and239,240Pu were determined in sea waters and sediments columns from the western North Pacific from 1980 to 1986.The239,240Pu/137Cs activity ratio in the water column shows a tendency to increase from the surface (10−3) to bottom waters (10−1), but the ratio in sediment is within a rather narrow range (10−2 to 10−1), indicating more effective removal of plutonium from the water column than137Cs. In regions south of 40‡N, the radionuclide inventories in the water column significantly exceed the estimated global fallout (stratospheric fallout due to the atmospheric nuclear explosion), especially in the case of239,240Pu. These excess inventories imply that local or close-in fallout derived from nuclear explosions in the equatorial North Pacific are well-preserved and retained in the regions, despite about 20 years since the atmospheric nuclear explosion moratorium. Data suggesting lateral transport of137Cs in surface water from north of 40‡N to southern regions is shown. Some data on90Sr contents are also shown.