Now showing items 21-30 of 50
Room temperature gas-solid reaction of titanium on glass surfaces forming a very low resistivity layer
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 ...
Estrogenic and serotonergic butenolides from the leaves of Piper hispidum Swingle (Piperaceae)
(Journal of Ethnopharmacology 129(2): 220–226, 2010)
Ethnopharmacological relevance: Our previous work has demonstrated that several plants in the Piperaceae family are commonly used by the Q’eqchi Maya of Livingston, Guatemala to treat amenorrhea, dysmenorrhea, and pain. ...
Removal of both N-nitrosodimethylamine and trihalomethanes precursors in a single treatment using ion exchange resins
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 ...
The role of chloramine species in NDMA formation
N-nitrosodimethylamine (NDMA), a probable human carcinogen disinfection by-product, has been detected in chloraminated drinking water systems. Understanding its formation over time is important to control NDMA levels in ...
Fisico-química de las aguas superficiales de la Cuenca del río Rincón, Península de Osa, Costa Rica
Hydrochemistry of the surface waters at the Rincon River Basin, Osa Peninsula, Costa Rica
The Rincon River Basin is characterized by steep and rugged topography with outcrops of recent sediments as well as igneous and sedimentary rocks. The area is mostly covered by forest (Tropical Wet Forest) and agricultural ...
Influence of rice field agrochemicals on the ecological status of a tropical stream
Many tropical countries contain a high density of protected ecosystems, and these may often be bordered by intensive agricultural systems. We investigated the chemical and ecological status of a stream connecting an area ...
Metals in coastal mollusks of Costa Rica
Metales en moluscos costeros de Costa Rica
The input of contaminants to coastal ecosystems is a global problem on the rise. Data on metal pollution from tropical sites is often lacking and pilot surveys are urgently needed to provide a general framework to estimate ...
Evaluation of a recent product to remove lipids and other matrix co-extractives in the analysis of pesticide residues and environmental contaminants in foods
This study demonstrates the application of a novel lipid removal product to the residue analysis of 65 pesticides and 52 environmental contaminants in kale, pork, salmon, and avocado by fast, low pressure gas chromatography ...
Analysis of glyphosate and aminomethylphosphonic acid in leaves from Coffea arabica using high performance liquid chromatography with quadrupole mass spectrometry detection
Glyphosate is a commonly applied herbicide in coffee plantations. Because of its non-selective mode of action it can damage the crop exposed through spray drift. Therefore, it is of interest to study glyphosate fate in ...
Ecotoxicological analysis during the removal of carbofuran in fungal bioaugmented matrices
Biomixtures are used for the removal of pesticides from agricultural wastewater. As biomixtures employ high content of lignocellulosic substrates, their bioaugmentation with ligninolytic fungi represents a novel approach ...