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Synthesis of 2-hydroxy-3-substituted naphthoquinones using the Heck reaction
(2007-06)
An efficient Heck coupling of 2-hydroxy-3-iodo-naphthoquinone with a series of electron-deficient alkenes in aqueous solution has been accomplished. The method is characterized by simple conditions and facile work-up to ...
Biodegradation of Pharmaceuticals by Fungi and Metabolites Identification
(2012-01-01)
Pharmaceutical compounds comprise a widely employed group of
therapeutic agents now considered as emerging micropollutants. This chapter
summarizes the state of the art in the degradation of pharmaceuticals by fungi ...
Guía de mediación pedagógica para aprendizajes comunitarios: comités de agua transfronte- rizos, Costa Rica - Nicaragua : pedagogía social, estrategias para la optimización del uso del agua para consumo humano en las comunidades de La Trocha e Isla Chica en los Chiles, Alajuela
(2021)
El equipo de profesores y profesoras de la Universidad Nacional y la Universidad de Costa Rica que elaboró esta guía conforma el proyecto de extensión y acción social universitaria: “Pedagogía social: estrategias para la ...
Propargylation of Carbonyl Compounds: An Efficient Method for the Synthesis of Homopropargyl Alcohols
(1998)
Controlled dilithiation of allene, with two equivalents of n-butytlithium, produces the propargyl dianion 5. The latter couple efficiently with carbonyl compounds to produce homopropargyl alcohols in high yields.
Desarrollo de sensores electroquímicos para la determinación de drogas sintéticas en fluidos biológicos y muestras de incautación
(2023-07-09)
La cantidad de nuevas sustancias psicoactivas, popularmente conocidas con términos como: drogas emergentes, drogas de diseño, drogas sintéticas o drogas recreativas, aumenta en el mercado global de las drogas cada año. El ...
Bile salts and derivatives: Rigid unconventional amphiphiles as dispersants, carriers and superstructure building blocks
(2015)
Steroidal surfactants like bile salts have a rigid amphiphilic structure significantly different from the typical head–tail one. As a result, these molecules show peculiar features in their self-assembly behavior and ...
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 ...
Ethyl propionate: Synergistic kairomone for african palm weevil,Rhynchophorus phoenicis L. (Coleoptera: Curculionidae)
(1994-04)
Small trunk pieces of a freshly felled 10-year-old oil palm,Elaeis quineensis (Jacq.), were placed in a modified Nalgene desiccator, and volatiles captured for six days on Porapak Q. Gas chromatographic (GC) analysis of ...
Electrochemical biosensor for quantitative determination of fentanyl based on immobilized cytochrome c on multi-walled carbon nanotubes modified screen-printed carbon electrodes
(2022)
Fentanyl is a powerful synthetic opioid used to treat severe pain. New administration routes toward its illegal consumption
for recreational purposes pose a growing threat to public health, either due to misuse or abuse ...
Assessing the reactive surface area of soils and the association of soil organic carbon with natural oxide nanoparticles using ferrihydrite as proxy
(2020-09-09)
Assessment of the surface reactivity of natural metal-(hydr)oxide nanoparticles is necessary for predicting ion adsorption phenomena in soils using surface complexation modeling. Here, we describe how the equilibrium ...