analysis of gross alpha, gross beta activities and beryllium- 7 concentrations in surface air: their variation and statistical prediction model

background: measurement of gross , gross activities, and cosmogenic beryllium-7 (7be) concentrations were made both daily and weekly during the years 2001- 2004 from samples of atmospheric aerosols filtered from the air at tehran nuclear research center (35 41' n) and zahedan (28 29' n). materials and methods: weekly aerosol samples were collected with the high-volume air samplers on cellulose filters to determine the 7be contents of samples, using a semiconductor gamma spectrometer. airborne dust samples were collected on daily basis on fiber glass filters and used to determine the gross and gross activities with automatic beta analyzer and a zns(ag) counter, respectively. in this study, the concentration and meteorological data were used to determine models for gross , gross and 7be. results: the air concentrations of gross and gross activities and 7be concentrations displayed lognormal distributions during the study period. both and 7be had maximum activity concentrations during warm mid-year months. conclusion: the models can be used to estimate the part of the trend in gross and in 7be levels that can be accounted for by-trends in local meteorology. there has been a satisfactory agreement between the results of the model and the measurements.