• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Radiation and Environmental Biophysics >Measurement of activity concentrations of 40K, 226Ra and 232Th for assessment of radiation hazards from soils of the southwestern region of Nigeria
【24h】

Measurement of activity concentrations of 40K, 226Ra and 232Th for assessment of radiation hazards from soils of the southwestern region of Nigeria

机译：测量 40 K， 226 Ra和 232 Th的活性浓度以评估尼日利亚西南地区土壤的辐射危害

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Activity concentrations of the selected radionuclides 40K, 226Ra and 232Th were measured in surface soil samples collected from 38 cities in the southwest region of Nigeria by means of gamma spectroscopy with a high-purity germanium detector. Measured activity concentration values of 40K varied from 34.9 ± 4.4 to 1,358.6 ± 28.5 Bq kg−1 (given on a dry mass (DM) basis) with a mean value of 286.5 ± 308.5 Bq kg−1; that of 226Ra varied from 9.3 ± 3.7 to 198.1 ± 13.8 Bq kg−1 with a mean value of 54.5 Bq kg−1 and a standard deviation of 38.7 Bq kg−1, while that of 232Th varied from 5.4 ± 1.1 to 502.0 ± 16.5 Bq kg−1 with a mean value of 91.1 Bq kg−1 and standard deviation of 100.9 Bq kg−1. The mean activity concentration values obtained for 226Ra and 232Th are greater than the world average values reported by the United Nations Scientific Committee on Effects of Atomic Radiation for areas of normal background radiation. Radiological indices were estimated for the radiation/health hazards of the natural radioactivity of all soil samples. Estimated absorbed dose rates in air varied from 12.42 ± 2.25 to 451.33 ± 19.06 nGy h−1, annual outdoor effective dose rates from 0.015 ± 0.003 to 0.554 ± 0.023 mSv year−1, internal hazard index from 0.10 ± 0.03 to 3.02 ± 0.16, external hazard index from 0.07 ± 0.01 to 2.60 ± 0.11, representative level index from 0.19 ± 0.03 to 6.84 ± 0.29, activity index from 0.09 ± 0.02 to 3.42 ± 0.15, and radium equivalent activity from 26.95 ± 5.04 to 963.15 ± 41.87 Bq kg−1. Only the mean value of the representative level index exceeds the limit for areas of normal background radiation. All other indices show mean values that are lower than the recommended limits.
机译：在西南地区38个城市收集的表层土壤样品中，测定了选定放射性核素 40 K， 226 Ra和 232 Th的活度浓度。尼日利亚使用带有高纯度锗探测器的伽马能谱仪。测量的 40 K的活动浓度值从34.9±4.4到1,358.6±28.5 Bq kg -1 （以干重（DM）为基础），平均值为286.5±308.5 Bq千克 -1 ; 226 Ra的平均值在9.3±3.7至198.1±13.8 Bq kg -1 之间，平均值为54.5 Bq kg -1 ，标准偏差为38.7 Bq kg −1 ，而 232 Th的标准偏差为5.4±1.1至502.0±16.5 Bq kg −1 ，平均值为91.1 Bq kg -1 ，标准偏差为100.9 Bq kg -1 。 226 Ra和 232 Th的平均活动浓度值大于联合国原子辐射影响科学委员会对正常背景区域的世界平均值辐射。估算了所有土壤样品的自然放射性的辐射/健康危害的放射学指标。估计的空气中吸收剂量率从12.42±2.25到451.33±19.06 nGy h -1 ，年室外有效剂量率从0.015±0.003到0.554±0.023 mSv年 -1 ，内部危害指数从0.10±0.03到3.02±0.16，外部危害指数从0.07±0.01到2.60±0.11，代表性水平指数从0.19±0.03到6.84±0.29，活动指数从0.09±0.02到3.42±0.15，以及镭等效活度从26.95±5.04到963.15±41.87 Bq kg -1 。仅代表性水平指数的平均值超过正常背景辐射区域的极限。所有其他指数显示的平均值均低于建议的限值。

著录项

相似文献

  • 外文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号