Artificial radionuclide entrance with solid and liquid phases of atmospheric precipitations on the earth surface in the Leningrad region in 1961-1973

Presented are results of observations of radionuclides of the artificial origin (Mn54, Sr90, Y91, Zr95, Ru103, Ru106, Cs137, Ce141,144, Eu155) falling out with the atmospheric precipitations near Leningrad in 1961-1973. The study of the quantitative distribution of radionuclides between the solid and liquid phases of the atmospheric precipitations testified to the constancy of the distribution of separate radionuclides and the independence of such a distribution on the kind of precipitations (rain, snow), the quantity of the disperse phase, proportion of suspended particles of the organic and inorganic origin, duration of their presence in the atmospheere. Based on the analysis of experimental and published data stated are factors conditioning the distribution of separate radionuclides between the solid and liquid phases of the atmospheric precipitations. The data cited testify to the firmness of the inclusion of a certain part of each radionuclide of Zr95, Nb95, Ru106, Sb125, Cs137, Ce144 into the faction of suspended particles which is hardly soluble in acids