Variation analysis of atmospheric Be activity concentrations with respect to precipitation.

Beryllium-7 activity concentrations in the atmosphere and precipitation were continuously measured every day between April 2011 and December 2015 in Dazaifu, western Japan. The measured data were quantitatively analyzed to determine the precipitation-induced variation in Be activity concentrations. The average concentrations on nonprecipitation and precipitation days were 5.

TRITIUM IN THE ENVIRONMENT.

Environmental tritium are natural and anthropogenic origins, the distribution has spread in atmosphere, hydrosphere and biosphere as a variety of chemical forms. The natural tritium is produced by nuclear reactions of neutron with N and O in the upper atmosphere, the production rate changes with 11-year cycle of the solar activity. The production and radioactive decay of natural tritium is balanced on the whole earth, results in the inventory of about 1 EBq.

Analysis of Factors Contributing to the Increase in Be Activity Concentrations in the Atmosphere.

In March 2013, increased Be activity concentrations in the atmosphere were observed for successive days in Dazaifu, western Japan. The daily Be activity concentration ranged from 0.93 to 14 mBq/m, with a monthly average of 8.

Cosmogenic Be: Particle size distribution and chemical composition of Be-carrying aerosols in the atmosphere in Japan.

The particle size distributions of airborne aerosols with Be were measured using cascade impactors at Dazaifu, a city in western Japan, in 2018 to observe their seasonal variation. Beryllium-7 was found to be adsorbed to aerosols with a particle size of less than 2.1 μm; in general, particles sized 0.

Atmospheric radionuclides transported to Fukuoka, Japan remote from the Fukushima Dai-ichi nuclear power complex following the nuclear accident.

Radionuclides were detected from the Fukushima nuclear accident at Fukuoka, Japan, 1000 km west of the Fukushima Dai-ichi nuclear power complex. Iodine-131 was first detected 3 d after the accident, indicating that it was probably transported dispersively because of local meteorological conditions, and not global air circulation. The maximum concentrations, 5.