摘要
一、前言根据文献[1]的报导,空气中^(232)Th浓度主要依赖于土壤中放射性核素的浓度和土壤的再悬浮因子两个因素。联合国原子辐射效应科学委员会推荐的地面空气中^(232)Th浓度的估算值就基于这一假设。根据这一假设估算空气中^(232)Th含量的文章目前尚不多见。
the measurements of concentration of ^(232)Th in air in wuhan area show thatthe daily average value is found to be 29.13×10^(-9)Bq/1 in the period from 1981to 1985 based on the measurements of 7346 samples. The highest daily averagevalue is 36.23×10^(-9) Bq/1 in the year 1983. The seasonal changes of the concen-tration of ^(232)Th in air is very obvious for the year 1984 and 1985, being highestin winter with a value of 41.93×10^(-9) Bq/1 in 1984 and 32.85×10^(-9) Bq/1 in 1985,and lowest in summer with values of 25.40×10^(-9) Bq/1 and 14.33×10^(-9)Bq/1 res-pectively. This obvious change with season is related to the weather condition. The concentration of ^(232)Th in air is highest in Qingshan region for six citiesin wuhan area with a value of 49.34×10^(-9)Bq/1 and lowest in wuchan regionwith a value of 18.35×10^(-9) Bq/1. This is due to the difference in the amount ofdust in the air in these regions.
出处
《原子能科学技术》
EI
CAS
CSCD
北大核心
1990年第1期67-69,87,共4页
Atomic Energy Science and Technology
