摘要
杭州附近地区的测量结果表明，地表空气中７Ｂｅ的浓度全年平均为４．６±２．０ｍＢｑ·ｍ－３，比ＵＮＳＣＥＡＲ的报告值高出５０％－８０％。其中１０、１１、１２月份的均值最高，达６．８±１．１ｍＢｑ·ｍ－３；２、６、７月份的均值最低，为２．０±０．１７ｍＢｑ·ｍ－３；４、５月份的浓度接近于全年平均值；表现出明显的与降水有关的季节性变化，而未显示出ＵＮＳＣＥＡＲ报道的与平流层沉降有关的春天最高、晚秋最低的变化规律。７Ｂｅ在杭州附近地区地表空气中的γ辐射年吸收剂量率为４．７×１０－１０Ｓｖ，在成人肺中的年吸收剂量为３．６×１０－８Ｓｖ，在总的环境剂量估算中可不予考虑。
he monthly 7Be monitoring results at 3 positions near Hangzhou are reported.The annual average 7Be concentration in the air above ground is 4.6±2.0mBq·m-3,about 50%-80% more than the value of UNSCEAR report. It reachs the amximum in October to December, the minimum in February and June to July, and approaches the mean value in April to May. These changes evidently relate to seasonal raining and do not follow UNSCEAR report, which indicates that the maximum occurs in spring and the minimum in late autumn caused by the subsidence from stratosphere.The 7Be radiation dose is also evaluated, which is much less than 222Rn and can be ignored.
出处
《核技术》
CAS
CSCD
北大核心
1994年第3期172-175,共4页
Nuclear Techniques
