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目的:监测与分析2017—2020年北京地区大气气溶胶中n 7Be和n 210Pb放射性活度浓度变化情况，为有效防治空气污染提供科学依据。n 方法:利用大流量空气气溶胶采样器(SnowWhite)采集气溶胶样品1 074份，其中春季、夏季、秋季和冬季分别采集275、266、262和271份。使用低本底高纯锗伽马谱仪(ORTEC)分析气溶胶样品中n 7Be和n 210Pb放射性活度浓度。n 结果:2017—2020年北京地区大气气溶胶中n 7Be放射性活度浓度的变化范围为0.56~14.84 mBq/mn 3，平均值为6.84 mBq/mn 3。n 210Pb放射性活度浓度的变化范围为0.01~9.37 mBq/mn 3，平均值为3.19 mBq/mn 3。2017—2020年北京大气气溶胶n 7Be和n 210Pb放射性活度浓度在春、夏、秋、冬四季中差异均有统计学意义(n F＝32.66、93.93，n P<0.05)，其中n 7Be放射性活度浓度春季最高，秋季次之，夏季和冬季最低，n 210Pb放射性活度浓度由高到低分别为冬季、秋季、春季、夏季。n 结论:2017—2020年北京地区大气气溶胶中n 7Be和n 210Pb放射性活度浓度处于正常涨落水平范围内。n “,”Objective:To monitor and analyze the activity concentrations of n 7Be and n 210Pb in atmospheric aerosol in Beijing from 2017 to 2020.n Methods:Totally 1 074 atmospheric aerosol samples were collected by high flow air sampler (SnowWhite) including 275 in spring, 266 in summer, 262 in autumn and 271 in winter and subjected to analysis by low background high-purity germanium gamma-ray spectrometery (ORTEC) to determine the activity concentrations of n 7Be and n 210Pb.n Results:The activity concentrations of n 7Be in atmospheric aerosol were from 0.56 to 14.84 mBq/mn 3, with an avearage of 6.84 mBq/mn 3, and from 0.01 to 9.37 mBq/mn 3 for n 210Pb, with an avearage 3.19 mBq/mn 3. The differences in activity concentrations of n 7Be and n 210Pb in atmospheric aerosol among differernt seasons were statistically significant (n F=32.66, 93.93, n P<0.05). Activity concentration ofn 7Be was highest in spring, followed by autumn, and lowest in summer and winter. Activity concentration of n 210Pb ranged from winter, autumn, spring to summer in descending order.n Conclusions:The activity concentrations of n 7Be and n 210Pb in atmospheric aerosol in Beijing from 2017 to 2020 fluctated within the range of normal level.n