化学分区的化学分区的研究
1Department of Environmental Science and Geology, Wayne State University, Detroit, MI 48202, United States of America.
The Science of the total environment
|June 9, 2023
概括
在底特律的道路沉积物中,大气沉降放射性核酸如7Be和210Pb/210Po揭示了沉积物的年龄和污染物流动性. 这项研究量化了210Po/210Pb比率,为城市沉积物动态提供了新的见解.
科学领域:
- 环境科学 环境科学
- 地质化学 地质化学
- 放射化学 放射化学是指辐射化学.
背景情况:
- 后工业城市的道路沉积物可以积累污染物.
- 大气中放射性核化物 (7Be,210Pb,210Po) 的沉积提供了天然的痕迹物.
研究的目的:
- 为了分析底特律道路沉积物中的放射性核化物.
- 用210Po/210Pb比率来确定道路沉积物的表面年龄.
- 为了研究沉积物中放射性核素的移动性.
主要方法:
- 收集和分析道路沉积物和土壤样本.
- 测量210Pb,210Po,7Be,226Ra和137Cs的含量. 这是一个非常好的方法.
- 大气沉积流和活动比率的量化.
- 沉积物部分的顺序提取.
主要成果:
- 在所有样本中观察到新的210Po/210Pb活性比率<1.0.
- 道路沉积物的平均表面年龄计算为146±62天.
- 数字建模预测了210Po/210Pb比率的动态平衡.
- 7Be和210Pb主要在Fe-Mn氧化物和残留分数中发现.
结论:
- 自然放射性核酸标记为沉积物的流动性和年龄提供了洞察力.
- 210Po-210Pb对为理解含有污染物沉积物提供了一个时间维度.
- 放射性核素分布在不同的分数中揭示了复杂化和传输机制.
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