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Evaluación de los efectos de la contaminación atmosférica y el ángulo de exposición sobre la corrosión del acero de bajo carbono y acero galvanizado en la región del Valle Central Occidental (VCO) de Costa Rica
(2023-05)
Costa Rica is a country that imports its metallic materials, this makes the evaluation of its corrosion losses of special interest, since they represent an average of 3% of the GDP. In particular, atmospheric corrosion is ...
Grids III: Hydrogen Bridges in Introductory Chemistry
Cuadrículas III: Puentes de Hidrógeno en Química General
(2021)
Based on IUPAC recommendations for the
definition of the hydrogen bond, a series of
grids is presented to provide instructors of
introductory chemistry courses with visual
examples of H-bridged systems. The grids ...
Aprovechamiento de los desechos de la industria del anodizado de aluminio en la síntesis de zeotipos tipo AlPO4-X y aplicación de estos en la captura de amoniaco
(2020)
La finalidad de este trabajo fue llevar a cabo la síntesis de zeotipos tipo AlPO4-X utilizando desechos provenientes de la industria de anodizado de aluminio (DAAl-1) en sustitución de la fuente de aluminio, estos desechos ...
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 ...
Estudio quimico de las hojas de tabernaemontana arborea rose
(1986)
From the leaves of Tabernaemontana arborea Rose (Apocynaceae) the triterpenoid lupeyl acetate and the indole alkaloids voacangine, 19 epivoacristine, vobasine and 19R-hydroxiconopharingine have been isolated and identified ...
A Chronoamperometric Screen Printed Carbon Biosensor Based on Alkaline Phosphatase Inhibition for W(VI) Determination in Water, Using 2-Phospho-l-Ascorbic Acid Trisodium Salt as a Substrate
(2015)
This paper presents a chronoamperometric method to determine tungsten in water using screen-printed carbon electrodes modified with gold nanoparticles and cross linked alkaline phosphatase immobilized in the working ...
General Chemistry Without Orbitals
(2020)
We illustrate the solutions of Schroedinger's equation for the hydrogen atom in coordinates of all four systems, and differentiate the applicability of orbitals in these four systems. We present reasons that future textbooks ...
ArsH protects Pseudomonas putida from oxidative damage caused by exposure to arsenic
(2020-03-23)
The two As resistance arsRBC operons of Pseudomonas putida KT2440 are followed by a downstream gene called arsH that encodes an NADPH‐dependent flavin mononucleotide reductase. In this work, we show that the arsH1 and (to ...
Caracterización de la calidad del agua de la Quebrada Sanatorio en Tierra Blanca ubicada en una zona agrícola de la provincia de Cartago y sus implicaciones para la salud pública
Quality of water from Quebrada Sanatorio (Tierra Blanca), in the county region of Cartago province and impacts on public health
Qualidade de água de Quebrada Sanatorio (Tierra Blanca), na região agrícola da província de Cartago, e seus impactos sobre a saúde pública
(2012-10)
Se monitoreó la calidad del agua de la Quebrada Sanatorio (Tierra Blanca, Cartago, Costa Rica), durante abril, junio, agos to y octubre de 2011. Se establecieron tres puntos de muestreo utilizando una metodología de ...