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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 ...
Uniqueness of radially symmetric positive solutions for -delta u+u=u(p) in an annulus
(ACADEMIC PRESS INC ELSEVIER SCIENCE, 2008)
Uniqueness of radially symmetric positive solutions for -delta u+u=u(p) in an annulus
(ACADEMIC PRESS INC ELSEVIER SCIENCE, 2008)
Resultados de existência, de não existência e de simetria de solução para o operador p-Laplaciano fracionário com múltiplas singularidades críticas e potencial de Hardy
(Universidade Federal de Minas GeraisBrasilICX - DEPARTAMENTO DE MATEMÁTICAPrograma de Pós-Graduação em MatemáticaUFMG, 2021-07-09)
In this doctoral thesis we consider a problem involving the fractional p-Laplacian
operator
(−∆p)
su −µ
|u|
p−2u
|x|
p s
=
|u|
p
∗
s
(β)−2u
|x|
β
+
|u|
p
∗
s
(α)−2u
|x|
α
(x ∈ R
N
) (0.7)
where ...
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 ...
Uniqueness of radially symmetric positive solutions for -Delta u+u=u(p) in an annulus
(ACADEMIC PRESS INC ELSEVIER SCIENCE, 2008-09-01)
In this article we prove that the semi-linear elliptic partial differential equation
-Delta u + u = u(p) in Omega
u > 0 in Omega. u = 0 on partial derivative Omega
possesses a unique positive radially symmetric ...
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 ...
Radial solutions of an elliptic equation with singular nonlinearity
(Academic Press Inc Elsevier ScienceSan DiegoEUA, 2009)