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目的:探讨2021年3月16日—2023年3月31日北京市空气中 7Be、 137Cs和 210Pb活度浓度的变化情况以及与温度、降水量、相对湿度、气压、PM10(仅限 137Cs)等气象参数的相关性。 方法:使用辐射自动监测站内的HRHA01-SFS1000/A超大流量空气采样器共采集了60个气溶胶样品，利用GMX-60型低本底反康高纯锗γ能谱仪测量气溶胶样品中 7Be、 137Cs和 210Pb的活度浓度，使用皮尔逊相关系数表征相关参数的相关性。 结果:7Be活度浓度春季、夏季、秋季与冬季各季度均值分别为4.31、3.53、3.09与2.45 mBq/m 3，范围为1.17～7.79 mBq/m 3，整体均值为(3.36±1.33)mBq/m 3； 137Cs活度浓度范围为0.39～8.49 μBq/m 3，均值为(0.59±1.47)μBq/m 3； 210Pb活度浓度春季、夏季、秋季与冬季各季度均值分别为0.53、0.44、0.72与0.75 mBq/m 3，范围为0.21～1.36 mBq/m 3，均值为(0.56±0.26)mBq/m 3。 7Be的活度浓度与温度、气压相关( r＝0.38、－0.40)、 137Cs的活度浓度与降水相关( r＝－0.41)、 210Pb的活度浓度与温度、气压相关( r＝－0.31、0.37)。空气中 137Cs活度浓度变化呈现出明显的季节性规律，一般在每年的春季(3～5月)出现峰值，与北京市春季沙尘较为频繁有关。空气中 210Pb的活度浓度受冬季煤炭燃烧供暖的影响，在11～3月期间会出现高峰值。 结论:北京市空气中 7Be、 137Cs、 210Pb活度浓度处于正常水平范围内，呈现出季节性的变化趋势。

Objective:To discusses the variations of 7Be, 137Cs and 210Pb activity concentrations in the air in Beijing from March 16, 2021 to March 31, 2023, and their correlation with temperature, precipitation, relative humidity, barometric pressure, PM10 (only limited to 137Cs) and other meteorological parameters. Methods:A total of 60 aerosol samples were collected using the HRHA01-SFS1000/A ultra-large flowair sampler in the automatic radiation monitoring station. The activity concentrations of 7Be, 137Cs and 210Pb in the aerosol samples were measured by GMX-60 low background anti-Compton high purity germanium gamma spectrometer. Pearson correlation coefficient was used to show the correlation of the relevant parameters. Results:The seasonal mean values of 7Be activity concentration were spring 4.31 mBq/m 3, summer 3.53 mBq/m 3, autumn 3.09 mBq/m 3 and winter 2.45 mBq/m 3, respectively, ranging from 1.17 to 7.79 mBq/m 3, with the overall mean of (3.36±1.33) mBq/m 3. The activity concentration of 137Cs ranged from 0.39 to 8.49 μBq/m 3, with an average of (0.59±1.47) μBq/m 3. The average activity concentrations of 210Pb were spring 0.53 mBq/m 3, summer 0.44 mBq/m 3, autumn 0.72 mBq/m 3 and winter 0.75 mBq/m 3, respectively, ranging from 0.21 to 1.36 mBq/m 3, with an average of (0.56±0.26) mBq/m 3. The activity concentration of 7Be was correlated with temperature and pressure ( r=0.38, -0.40), the activity concentration of 137Cs was correlated with precipitation ( r=-0.41), and the activity concentration of 210Pb was correlated with temperature and pressure ( r=-0.31, 0.37). The variation of 137Cs activity concentration in the air showed an obvious seasonal pattern, and the peak value generally appears in spring of each year (March to May), which was related to the frequent spring dust in Beijing. The activity concentration of 210Pb in the air was affected by coal combustion heating in winter, and has a peak value during November to March. Conclusions:The activity concentrations of 7Be, 137Cs and 210Pb in the air in Beijing are within the normal range, showing a seasonal trend.