The effects of large-scale atmospheric flows on berylium-7 activity concentration in surface air.

Understanding the exchange mechanism between stratosphere and troposphere is one of the most important concerns of meteorologists and climatologists for decades. Different methods are being adopted to study those mechanisms. One of those methods is the study upon the tropospheric concentration of conserve or passive entities with stratospheric origin.

Analysis of gross alpha, gross beta activities and beryllium-7 concentrations in surface air: their variations and statistical prediction model.

Measurement of gross alpha, gross beta 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). Weekly aerosol samples collected with the high-volume air samplers on cellulose filters were used to determine the 7Be contents of samples, using a semiconductor gamma spectrometer. Airborne dust samples were collected daily on fiber glass filters and used to determine the gross beta and gross alpha activities with automatic beta analyzer and a ZnS(Ag) counter, respectively.