【摘要】 本文报道了1985年鄱阳湖湖底沉积物放射性水平的调查结果。沉积物中 U、Th、²²⁶Ra、⁴⁰（?）和¹³⁷Cs 的比活度分别为64.8、67.9,58.9、676.1和3.5Bq/kg;用¹³⁷Cs 测龄方法作了沉积物泥芯垂直深度的年代定位,由此得知1985—1958年对应深度沉积物中 U、Th、²²⁶Ra 和⁴⁰K 的比活度与1957—1930年对应深度沉积物比较无显著性差异;U、Th 和²²⁶Ra 的浓集因予分别为5.2×10⁴13.9×10⁴和4.8×10⁴L/kg。更多还原

【Abstract】 This paper presents the investigation results of radioact- ive levels in the sediment at the bottom of Poyang Lake in 1985.Thespecific activities of U,Th,²²⁶Ra,⁴⁰K and ¹³⁷Cs in the sediment were64.8,67.9,58.9,676.1 and 3.5 Bq/kg,respectively.The ages of verti-cal depth of the soil core of the sediment was determined based on theage measurement method with ¹³⁷Cs.It was shown that the specific acti-vities of U,Th,²²⁶Ra and ⁴⁰K in the sediment during 1985—1958 werenot obviously different from those in the sediment during 1957—1930.The concentration factors of U,Th and ²²⁶Ra were（5.2,13.9 and4.8）×10⁴ L/kg.更多还原