Browsing Química by Title
Now showing items 106-125 of 156
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Pheromone chirality of african palm weevil, Rhynchophorus phoenicis (F.) and palmetto weevil, Rhynthophorus crueniatus (F.) (Coleoptera: Curculionidae)
(1994-09)There are four stereoisomers of both 3-methyl-octan-4-ol, the aggregation pheromone of the African palm weevil,Rhynchophorus phoenicis (F.) and 5-methyl-octan-4-ol, the aggregation pheromone of the palmetto weevil,Rhynchophorus ... -
Pheromone chirality of asian palm weevils,Rhynchophorus ferrugineus (Oliv.) andR. vulneratus (Panz.) (Coleoptera: Curculionidae)
(1996-02)Production of 4-methyl-5-nonanol, and 4-methyl-5-nonanone by two sympatric Asian palm weevils,Rhynchophorus ferrugineus (Oliv.) andR. vulneratus (Panz.) suggested that enantiospecificity of either compound could impart ... -
Photoreactivity of Oil and Alcoholic Diterpenic Varnishes: Key Role of the Polymerization Process
(2020)he conservation of artworks is a key issue in cultural heritage. The alterations of the varnish could be linked mainly to the photopolymerization of the natural resin. The photodegrada- tion of sandarac and rosin under ... -
Polifenoides de Uncaria Tormentosa y propiedades fitoterapéuticas de uña de gato costarricense
(2012-12-18)Esta invención se refiere a extractos fenólicos conteniendo procianidinas, propelargonidinas y flavanolignanos, con propiedades/actividades potencialmente beneficiosas para la salud humana, y obtenidos a partir de las ... -
Predation of the Rolled-Leaf Beetle Cephaloleia kressi García-Robledo (Coleoptera: Chrysomelidae: Cassidinae) by the Rove Beetle Phanolinus Sp. (Coleoptera: Staphylinidae: Xanthopygina) in a Montane Forest of Costa Rica
(2020-12-22)The genus Cephaloleia Chevrolat includes 215 species, known as rolled-leaf beetles, all of which are restricted to the Neotropics (Garcı́a-Robledo et al. 2015; Staines and Garcı́a-Robledo 2014). These beetles complete their ... -
Pristine but metal-rich Río Sucio (Dirty River) is dominated by Gallionella and other iron-sulfur oxidizing microbes
(2017-03)Whether the extreme conditions of acidity and heavy metal pollution of streams and rivers originating in pyritic formations are caused primarily by mining activities or by natural activities of metal-oxidizing microbes ... -
Producción de un detergente líquido ambientalmente preferible y estrategia de lanzamiento al mercado del Valle Central Occidental de Costa Rica
(2009)Se determinó la viabilidad de instalar una empresa de productos químicos preferibles para el ambiente, en el cantón de Poás de Alajuela, Costa Rica. Con este propósito se seleccionó una formulación de un detergente líquido ... -
Purpureocillium roseum sp. nov. A new ocular pathogen for humans and mice resistant to antifungals
(2020)Background Infectious keratitis is the main cause of preventable blindness worldwide, with about 1.5–2.0 million new cases occurring per year. This inflammatory response may be due to infections caused by bacteria, fungi, ... -
Rapid shift in microbial community structure in a neutral hydrothermal hot spring from Costa Rica
(2020)In this work, we characterize the geochemistry and microbial community of Bajo las Peñas, a neutral (pH 6.5-7.4), hot spring (T = 62.0-68.0°C) located near Turrialba Volcano, Costa Rica. The microbiota at its two sources ... -
Reactivity and structure of derivatives of 2-hydroxy-1,4-naphthoquinone (lawsone)
(2007-11)The structures of two derivatives of 2-hydroxy-1,4-naphthoquinone (lawsone) are examined using the density functional theory (DFT) hybrid functional B3LYP. Using the optimized structure of lawsone acetate, the reactivity ... -
Removal of both N-nitrosodimethylamine and trihalomethanes precursors in a single treatment using ion exchange resins
(2017-11-01)Drinking water utilities are relying more than ever on water sources impacted by wastewater effluents. Disinfection/oxidation of these waters during water treatment may lead to the formation of several disinfection ... -
Removal of N-nitrosodimethylamine precursors with powdered activated carbon adsorption
(2016-01-01)The main objective of this study was to examine the roles of powdered activated carbon (PAC) characteristics (i.e., surface chemistry, pore size distribution, and surface area) in the removal of N-nitrosodimethylamine ... -
Reproducible molecular networking of untargeted mass spectrometry data using GNPS
(2020-05-13)Global Natural Product Social Molecular Networking (GNPS) is an interactive online small molecule–focused tandem mass spectrometry (MS2) data curation and analysis infrastructure. It is intended to provide as much chemical ... -
Richness and metallo-tolerance of cultivable fungi recovered from three high altitude glaciers from Citlaltépetl and Iztaccíhuatl volcanoes (Mexico)
(2020)In Mexico little is known about high-altitude glacial psychrotolerant or psychrophilic fungal species, with most glacial fungi isolated from polar environments or Alpine glaciers. It has been documented that some of these ... -
Room temperature gas-solid reaction of titanium on glass surfaces forming a very low resistivity layer
(2016-09)Titanium films were deposited on quartz, glass, polyamide and PET substrates in a high vacuum system at room temperature and their electrical resistance monitored in vacuo as a function of thickness. These measurements ... -
Sex pheromone components of Diatraea considerata (Heinrich) (Lep., Pyralidae)
(1998-08)Three aldehydes. (Z)-11-hexadecenal (Z11–16:Ald), (Z)-7-hexadecenal (Z7–16:Ald) and (Z)-13-octadecenal (Z13–18:Ald), in a ratio of 74:23:3 are female-produced sex pheromone components of the pyralid moth, Diatraea considerata ... -
Short communication: Effect of different kefir grains on the attributes of kefir produced with milk from Costa Rica
(2020)Kefir is an artisanal product that is gaining scientific attention due to its increase in consumption attributed to its potential health benefits. The effect on the quality attributes of kefir grains of different origin ...