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The mechanism of 234U 238U activity ratio enhancement in karstic limestone groundwater
(Elsevier B.V., 1993-01-05)
Experimental etch/leach of Carboniferous Limestone gravels on a laboratory time-scale has demonstrated that 234U 238U activity ratios (AR's) greater than the radiochemical equilibrium value may be generated on short ...
The dissolved uranium concentration and 234U/238U activity ratio in groundwaters from spas of southeastern Brazil
(2017-01-01)
This paper describes the natural radioactivity due to 238U and 234U in 75 water sources from spas located in 14 municipalities in São Paulo and Minas Gerais states, Brazil. These waters are extensively utilized for drinking ...
The mechanism of 234U 238U activity ratio enhancement in karstic limestone groundwater
(Elsevier B.V., 2014)
The mechanism of 234U 238U activity ratio enhancement in karstic limestone groundwater
(Elsevier B.V., 2014)
The assessment of soils contamination from U-238 and U-234 disequilibria data
(2018-01-01)
Understanding processes involved in the soils formation is important for appropriate assessment of contamination occurring in the superficial horizons. Several tools have been used for such purpose, including the natural ...
Nitrification processes in groundwaters evidenced by modification on the U contents and U-234/U-238 activity ratios
(Computational Mechanics Publications Ltd, 1998-01-01)
Groundwaters from the Botucatu-Piramboia aquifer system located at the Parana sedimentary basin in Brazil and sampled at Ribeirao Preto city, São Paulo State, were chemically and isotopically analysed, with the aim of ...
Nitrification processes in groundwaters evidenced by modification on the U contents and U-234/U-238 activity ratios
(Computational Mechanics Publications Ltd, 1998-01-01)
Groundwaters from the Botucatu-Piramboia aquifer system located at the Parana sedimentary basin in Brazil and sampled at Ribeirao Preto city, São Paulo State, were chemically and isotopically analysed, with the aim of ...
Nitrification processes in groundwaters evidenced by modification on the U contents and 234U/238U activity ratios
(1998-01-01)
Groundwaters from the Botucatu-Piramboia aquifer system located at the Parana sedimentary basin in Brazil and sampled at Ribeirao Preto city, Sao Paulo State, were chemically and isotopically analyzed, with the aim of ...
Some applications of the natural uranium isotopes238U and 234U in environmental studies
(2009-02-01)
238U is the principal isotope of natural U (99.72% abundance) and is the progenitor of the (4n+2) series of radioelements. The isotope 234U is radiogenic and the decay chain from 238U through 234U proceeds as follows: 238U ...
Uranium isotopes in groundwater occurring at Amazonas State, Brazil
(Elsevier B.V., 2015-03-01)
This paper reports the behavior of the dissolved U-isotopes U-238 and U-234 in groundwater providing from 15 cities in Amazonas State, Brazil. The isotope dilution technique accompanied by alpha spectrometry were utilized ...