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Caracterización fisicoquímica del agua superficial en la subcuenca del río La Paz, San Ramón, Alajuela Costa Rica; como indicador del impacto ambiental por urbanismo en la zona
(2020)
El río La Paz es uno de los afluentes del río Barranca ubicado en el distrito Piedades Norte de San Ramón. Esta zona se caracteriza por ser montañosa de población rural en crecimiento, en la que se llevan a cabo actividades ...
Determinación colorimétrica de hierro en agua potable mediante la utilización de imágenes obtenidas con el teléfono celular
(2023-03-09)
La colorimetría de imágenes digitales se basa en la extracción de coordenadas de color de imágenes captadas con dispositivos como: escáneres, cámaras digitales y teléfonos celulares. El hierro es uno de los elementos más ...
Reconnaissance of selected PPCP compounds in Costa Rican surface waters
(2011-10-15)
Eighty-six water samples were collected in early 2009 from Costa Rican surface water and
coastal locations for the analysis of 34 pharmaceutical and personal care product
compounds (PPCPs). Sampling sites included areas ...
Inhibition of granulocyte elastase activity by caffeic acid derivatives
(1999)
In former studies it was shown that bornyl derivates may contribute to the anti-inflamatory activity of some drugs, such as Verbesia turbacensis, Notopterygium incisum or Coreopsis mutica.
Unusual Microbial Xylanases from Insect Guts
(2004-06-07)
Recombinant DNA technologies enable the direct isolation and expression of novel genes from biotopes containing complex consortia of uncultured microorganisms. In this study, genomic libraries were constructed from microbial ...
Synthesis of Iodinated Naphthoquinones Using Morpholine-Iodine Complex
(Synthetic Communications Vol. 34, No. 18, pp. 3389–3397, 2004, 2004)
The efficient synthesis of 2‐hydroxy‐3‐iodo‐1,4‐naphthoquinone (3), 2‐amino‐3‐iodo‐1,4‐naphthoquinone (4), and 2‐iodo‐1,4‐naphthoquinone (5) have been developed using the parent naphthoquinone in combination with the ...
Desarrollo y verificación de metodologías electroquímicas para la determinación de antimonio, plomo y otros componentes orgánicos presentes en residuos de disparo
(2022)
El análisis de residuos de disparo tanto inorgánicos como orgánicos, presentes en escenas del crimen, ha sido uno de los problemas más complicados en la ciencia forense debido a que la cantidad de muestra es muy limitada ...
Studies of methamidophos-C-14 in Costa Rican vegetables and soils
(1984)
In order to see the effect of time lapse between the last application of methamidophos and harvesting insecticide was applied on lettuce plants (6,84 μCi in one experiment and 4,03 μCi in the other experiment). Analysis ...
Aggregation Pheromone of Coconut Rhinoceros Beetle, Oryctes rhinoceros (L.) (Coleoptera: Scarabaeidae)
(1995-10)
Male coconut rhinoceros beetles,Oryctes rhinoceros (L.), produce three sex-specific compounds, ethyl 4-methyloctanoate, ethyl 4-methylheptanoate, and 4-methyloctanoic acid, the first of which is an aggregation pheromone. ...
Drying kinetics as Tool for the Assessment of Dynamic Porosity of Catalyst-Support Materials
(2018)
Critical drying fraction data (xc) were obtained for a series of porous materials, frequently used
as supports for heterogeneous catalysts. This kinetic parameter correlates well with the secondorder rate constants for ...