J. A. Rodríguez

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In this work optical properties of SiO X ð0 , X , 2Þ layers obtained by plasma enhanced chemical vapor deposition are studied. Infrared spectra and refractive index dependences with the reactant gases flow ratio R are explained for as deposited, aged and thermally treated samples in the R range from 9.17 to 110. Variations are found to be influenced mainly(More)
SnO 2 nanoribbons with exposed (1 0 1 h) and (0 1 0) surfaces have recently been demonstrated to be highly effective NO 2 sensors even at room temperature. The sensing mechanism is examined here through first principles density functional theory (DFT) calculations. We show that the most stable adsorbed species involve an unexpected NO 3 group doubly bonded(More)
Eggs are sources of protein, fats and micronutrients that play an important role in basic nutrition. However, eggs are traditionally associated with adverse factors in human health, mainly due to their cholesterol content. Nowadays, however, it is known that the response of cholesterol in human serum levels to dietary cholesterol consumption depends on(More)
In the present work, pattern synthesis of linear arrays using APSO is presented. APSO algorithm is employed for the synthesis of uniformly spaced arrays of two classes using unequal phases with equal amplitudes and with unequal amplitudes. The main objective of this work is to minimize the sidelobe level with a constraint on beam width and to perform null(More)
An amperometric flow biosensor for oxalate determination in urine samples after enzymatic reaction with oxalate oxidase immobilized on a modified magnetic solid is described. The solid was magnetically retained on the electrode surface of an electrode modified with Fe (III)-tris-(2-thiopyridone) borate placed into a sequential injection system preceding the(More)
A method is presented for magnetic solid phase extraction of tartrazine from nonalcoholic beverages. The method involves the extraction and clean-up by activated carbon covered with magnetite dispersed in the sample, followed by the magnetic isolation and desorption of the analyte by basified methanol. The tartrazine eluted from the magnetic support was(More)
Certain antenna applications require Dual-beam radiation patterns. The main aim of this paper is to generate the dual-beam radiation patterns from an array of isotropic radiators with single prefixed amplitude distribution. The optimal phase excitations are obtained using Particle Swarm Optimization. Beam 1 is a highly directive pencil beam and beam 2 is a(More)
A novel and facile method was developed to produce hybrid graphene oxide (GO)-polyelectrolyte (PE) capsules using erythrocyte cells as templates. The capsules are easily produced through the layer-by-layer technique using alternating polyelectrolyte layers and GO sheets. The amount of GO and therefore its coverage in the resulting capsules can be tuned by(More)
We report the first collection of Anopheles pictipennis from northern Chile, particularly sectors of Totoral, Perales, Puerto Viejo, and Salinas in the Atacama region. Adults were captured using human bait, while larvae and pupae were collected from various habitats including ponds, puddles left by overflowing river water, edges along river banks, wells,(More)
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