Инд. авторы:	Vosel Y.S, Vosel S., Melgunov M., Lazareva E., Kropacheva M.Y., Strakhovenko V.D.
Заглавие:	Discussions on the driving mechanism of postdepositional migration of Am-241 and Cs-137 in organomineral sediments (Lake Krugloe, Tomsk region, Russia)
Библ. ссылка:	Vosel Y.S, Vosel S., Melgunov M., Lazareva E., Kropacheva M.Y., Strakhovenko V.D. Discussions on the driving mechanism of postdepositional migration of Am-241 and Cs-137 in organomineral sediments (Lake Krugloe, Tomsk region, Russia) // Environmental Science and Pollution Research. - 2019. - Vol.26. - Iss. 19. - P.19180-19188. - ISSN 0944-1344. - EISSN 1614-7499.
Внешние системы:	DOI: 10.1007/s11356-019-04726-w; РИНЦ: 38705434; PubMed: 31065980; SCOPUS: 2-s2.0-85065505333; WoS: 000473041000019;
Реферат:	eng: A core of bottom sediments from Lake Krugloe located within the 30km influence zone of the Siberian Chemical Plant (located in the city of Seversk Tomsk-7) was studied to determine scales and rates of migration of artificial radionuclides Cs-137 and Am-241 in organomineral sediment. It was found that the main portion of Cs-137 and Am-241 was contained in the sediment interval above 10cm. This means that the horizon of 10cm corresponds to 1950the time of the start of widespread tests of nuclear weapons. The Pb-210(ex) dates also confirm that this particular horizon was formed in the 1950s. Pore waters in the core above the 10cm horizon are in oxidizing conditions. The depth of the oxidized/reduced boundary was determined from the distribution of redox-sensitive elements Fe and U dissolved in the pore solution. The core distribution of Cs-137 is a slightly sloping step, with the lower edge at the 10cm level. The smearing of the lower boundary of this distribution showing the scale of Cs-137 migration made it possible to estimate the diffusion mobility of Cs-137. Its diffusion coefficient turned out to be of the order of 10(-8)cm(2)s(-1). As shown by measurements, the scale of migration of Am-241 and the scale of migration of Cs-137 have similar values. Theoretical analysis carried out in this work shows that the most probable mechanism of Cs-137 and Am-241 migration in the pore solution of lake sediment is the migration of colloidal particles to which these radionuclides are strongly bound. Calculation of the diameter of such particles by the Stokes-Einstein formula shows that they have submicron dimensions (d approximate to 400nm). No evidence was found that the change in redox conditions in the sediment had an effect on migration of Am ions in pore solution.
Ключевые слова:	MANGANESE; OXIDATION; DEPOSITION; ACCUMULATION; TRANSPORT; CONTAMINATION; RADIONUCLIDES; URANIUM; PB-210; Diffusion coefficient; Lake sediments; Radionuclides migration; Am-241; Cs-137; DYNAMICS;
Издано:	2019
Физ. характеристика:	с.19180-19188