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Artículo
Simple model with facilitated dynamics for granular compaction
(American Physical Society, 1999)
A simple lattice model is used to study compaction in granular media. As in real experiments, we consider a series of taps separated by large enough waiting times. The relaxation of the density exhibits the characteristic ...
Artículo
Modelling the suspended matter distribution in an estuarine system : Application to the Odiel river in southwest Spain
(Elsevier, 1996)
A numerical model which solves the advective-diffusive dispersion equation for suspended matter and includes the deposition and resuspension is presented. The model requires the simultaneous solution of the hydrodynamic ...
Artículo
Glassy behavior in a simple model with entropy barriers
(American Physical Society, 1997)
We study the dynamical behavior of a system with a variable number of particles n. The empty state n=0 is the ground state, while all the other states n>0 are degenerate in energy. In equilibrium, the mean number of particles ...
Artículo
Modelling the Distribution of Radionuclides in Deep Ocean Water Columns. Application to 3H, 13 Cs and 239, 246Pu
(Elsevier, 1998)
A one-dimensional model to simulate the dispersion of radionuclides down deep water columns has been developed. The model includes the transfers of radionuclides between water, suspended matter and bottom sediments. Such ...
Artículo
Anthropogenic contamination analyzed by TTPIXE in samples from the Odiel salt marsh at the SW Spain
(Springer, 1997)
The studied marsh area is located at the southwest of Spain in an estuarine system formed by the confluence of the Odiel river and the Atlantic ocean. 23 samples collected in the marsh have been analysed by Thick Target ...
Artículo
Enhanced U and Th concentrations in soils from a wet marshland washed by contaminated riverwaters
(Elsevier, 1996)
A study of the presence of U and Th isotopes in soil samples from a saline wet Marshland located close to a phosphoric acid production factory is presented. The samples were collected during low tide in areas washed by ...
Artículo
Lie symmetries and multiple solutions in lambda-omega reaction-diffusion systems
(IOP, 1997)
Lie theory of transformation groups is applied to the study of lambda-omega reaction-diffusion systems in two-dimensional media. Our study proves that they are invariant with respect to a five-parameter symmetry group. ...
Artículo
The distribution of U, Th and 226Ra derived from the phosphate fertilizer industries on an estuarine system in Southwest Spain
(Elsevier, 1994)
This paper reports an extensive study of the presence of natural radioactivity around a phosphate fertilizer factory complex situated in an estuarine area of southwest Spain. The study has concluded that the wastes from ...
Artículo
Overdamped sine-Gordon kink in a thermal bath
(1999)
We study sine-Gordon kink diffusion at finite temperature in the overdamped limit. By means of a general perturbative approach, we calculate the first- and second-order ~ in temperature ! contributions to the ...
Ponencia
A Study on the Dependence of Water Tree Permittivity with Time
(IEEE, 1996)
During the growth of water trees in the insulation of a cable the distribution of the electric field is modified because of the local change of the dielectric properties of the material. It results a local enhancement ...