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Dispersion analysis of twist-symmetric dielectric waveguides
(MDPI, 2021)
We propose a circular twist-symmetric dielectric waveguide that is polarization-selective. In the practical implementation of optical fibers, a selective circular polarization is more convenient than its linearly polarized ...
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Vaccination compartmental epidemiological models for the delta and omicron SARS-CoV-2 variants
(Elsevier, 2024-01)
We explore the inclusion of vaccination in compartmental epidemiological models concerning the delta and omicron variants of the SARS-CoV-2 virus that caused the COVID-19 pandemic. We expand on our earlier compartmental-model ...
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Discrete breathers in Klein–Gordon lattices. A deflation-based approach
(American Institute of Physics, 2023-11-21)
Deflation is an efficient numerical technique for identifying new branches of steady state solutions to nonlinear partial differential equations. Here, we demonstrate how to extend deflation to discover new periodic orbits ...
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Standing and traveling waves in a model of periodically modulated one-dimensional waveguide arrays
(American Physical Society, 2023-08)
In the present work we study coherent structures in a one-dimensional discrete nonlinear Schrödinger lattice in which the coupling between waveguides is periodically modulated. Numerical experiments with single-site initial ...
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Radioactivity of phosphogypsum in the south-west of Spain
(OXFORD UNIV PRESS, 1998)
Phosphogypsum is the by-product of producing phosphoric acid by reacting phosphate rock with sulphuric acid. In the south-west of Spain, and near the town of Huelva, there is a big industrial complex with some factories ...
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External radiation assessment in a wet phosphoric acid production plant
(PERGAMON-ELSEVIER SCIENCE LTD, 2009)
The factories dedicated to the production of phosphoric acid by the so-called wet acid method are usually considered typical NORM industries, because the phosphate rock used as raw material usually contains high concentrations ...
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Characterisation of the plutonium isotopic composition of a sediment core from Palomares, Spain, by low-energy AMS and alpha-spectrometry
(ELSEVIER SCIENCE BV, 2010)
The measurement of plutonium isotopes, 239Pu and 240Pu, at 670 kV on the compact accelerator mass spectrometry (AMS) system at the Centro Nacional de Aceleradores (CNA) in Seville, Spain, is now a reality. In this work, ...
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Certified reference materials for radionuclides in Bikini Atoll sediment (IAEA-410) and Pacific Ocean sediment (IAEA-412)
(PERGAMON-ELSEVIER SCIENCE LTD, 2016)
The preparation and characterization of certified reference materials (CRMs) for radionuclide content in sediments collected offshore of Bikini Atoll (IAEA-410) and in the open northwest Pacific Ocean (IAEA-412) are described ...
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Overcoming ICP-QMS instrumental limitations for Tc-99 determination in environmental solid samples using radiochemistry
(PERGAMON-ELSEVIER SCIENCE LTD, 2006)
Besides its capabilities, quadrupole-based ICP-MS counting establishes several limitations on 99Tc analysis in environmental samples. Overcoming these limitations requires the use of radiochemical methods. We have developed ...
Artículo
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A comparison between active and passive techniques for measurements of radon emanation factors
(PERGAMON-ELSEVIER SCIENCE LTD, 2009)
Some radon related parameters have been determined through two different techniques (passive and active) in soil and phosphogypsum samples. Emanation factors determined through these techniques show a good agreement for ...