分类: 核科学技术 >> 粒子加速器 提交时间: 2023-06-18 合作期刊: 《Nuclear Science and Techniques》
摘要:The concentration of the natural ultra-trace radionuclides 36Cl and 236U in the uranium depended on the neutron flux. In this article, a method for measuring 36Cl and 236U in the same uranium mineral with accelerator mass spectrometry was developed in China Institute of Atomic Energy, providing a protocol of the potential application of 236U in uranium mining, environmental, and geological research. The two samples were from Guangxi and Shanxi province, China, and their ratios 36Cl/Cl and 236U/238U were measured. More experimental data conduced to understand the natural nuclides in the uranium mineral. We plan to conduct more efforts on the research.
分类: 物理学 >> 核物理学 提交时间: 2023-05-31
摘要:The spatial distributions of 239+240Pu and 137Cs in soils from Longji Rice Terraces were investigated to evaluate soil erosion. The activity concentrations of 239+240Pu and 137Cs in the surface soils of the paddy fields were in the range of 0.089-0.734 and 1.80-7.88 mBq/g, respectively. The activities of 239+240Pu and 137Cs showed very similar distribution trends, first increasing and then decreasing with increasing elevation. The 240Pu/239Pu atom ratios in the surface soils ranged from 0.162–0.232. The activities of 239+240Pu and 137Cs in the soil cores tended to be uniformly distributed within the plowed layer and declined exponentially below this depth. The mean soil erosion rates of Longji Rice Terraces estimated by 239+240Pu and 137Cs tracer methods were 5.44 t/(ha·a) and 5.16 t/(ha·a), respectively, which demonstrated that plutonium can replace 137Cs as an ideal tracer for soil erosion research in the future. Landform features are the main factors affecting the distribution of plutonium and 137Cs as well as soil erosion in the Longji Rice Terraces.