Browsing Artículos científicos by Title
Now showing items 206-225 of 241
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Rainfall, groundwater, and surface water isotope data from extreme tropical cyclones (2016-2019) within the Caribbean Sea and Atlantic Ocean basins
(Elsevier, 2020-06)Under a changing climate, projections estimate that over the next thirty years, extreme Tropical Cyclones (TCs) will increase in frequency, with two to three times more Category 4 and 5 hurricanes in the Atlantic basin ... -
Recovery of acetate by anion exchange with consecutive CO2-expanded methanol desorption: A model-based approach
(Elsevier BV, 2018-04-07)Production of bio-based acetate is commonly hindered by the high costs of the downstream processing. In this paper, a model is developed to describe a new method that recovers acetate salts using anion exchange resins, and ... -
Remote Piloting UAS in Extreme Environments with Challanging Climatic Conditions - An Overview of Modern UAS Capabilities in the Field of Volcanology, Geosciences, Atmospheric Chemistry and Interplanetary Exploration
(ADVANCED ENGINEERING DAYS (AED), 2022-09)Unmanned Aerial Systems have recently had advanced payloads configured by engineers for various atmospheric sampling experiments and have been proven a successful and innovative technology. Climatic stability in volcanic ... -
Renewable fatty acid ester production in Clostridium
(Nature Communications, 2021-07-16)Bioproduction of renewable chemicals is considered as an urgent solution for fossil energy crisis. However, despite tremendous efforts, it is still challenging to generate microbial strains that can produce target biochemical ... -
Residual nitrite in processed meat products in Costa Rica: Method validation, long-term survey and intake estimations
(Elsevier Ltd, 2021-05-12)Ingestion of high amounts of nitrite due processed meat consumption could produce negative effects in human health. Here, we investigate long-term residual sodium nitrite content in processed meat products in Costa Rica ... -
Revisiting the fundamentals of p-nitrophenol analysis for its application in the quantification of lipases activity. A graphical update
(Universidad Nacional (Costa Rica), 2020-07-31)p-Nitrophenol (pNP) is a widely used compound for analytical determinations of several esterases (EC. 3.1.1.X), including lipases (E.C. 3.1.1.3). Most enzymatic measurements employ pNP derivatives such as ... -
Saneamiento de aguas residuales mediante humedales artificiales en el Museo de Cultura Popular de la Universidad Nacional
(Universidad Nacional (Costa Rica), 2013-06)El cumplimiento de los Objetivos de Desarrollo del Milenio en términos de acceso sostenible al saneamiento requiere incrementar el desarrollo de programas de investigación que promuevan opciones tecnológicas simples y de ... -
Scattering of light by colloidal aluminosilicate particles Produces the unusual sky-blue color of Río Celeste (Tenorio Volcano Complex, Costa Rica)
(2013-09-18)Río Celeste (Sky-Blue River) in Tenorio National Park (Costa Rica), a river that derives from the confluence and mixing of two colorless streams-Río Buenavista (Buenavista River) and Quebrada Agria (Sour Creek)-is renowned ... -
Self-assembly study of type I collagen extracted from male Wistar Hannover rat tail tendons
(BioMed Central Ltd, 2020-11-23)Background: Collagen, the most abundant protein in the animal kingdom, represents a promising biomaterial for regenerative medicine applications due to its structural diversity and self-assembling complexity. Despite ... -
Síntesis de precursores tipo 1,8-naftilimida: propiedades y usos potenciales para la detección selectiva de metales en agua
(Universidad Nacional (Costa Rica), 2019)El objetivo del presente trabajo fue sintetizar moléculas (cromóforos) que tuviesen la capacidad de combinarse con sustancias macrocíclicas para preparar macromoléculas (quimiosensores) que pudiesen utilizarse para la ... -
Síntesis y caracterización de nanosílices funcionalizadas injertadas con 3-aminopropil trietoxisilano para ser utilizadas en adhesivos de poliuretano
(Universidad del País Vasco (España), 2007-03)En este trabajo se presentan los resultados obtenidos al modificar superficialmente una sílice pirogénica hidrófila comercial, con una superficie específica de 200 m2/g, a la que se le injertó 3-aminopropiltrietoxisilano. ... -
Síntesis, propiedades y aplicaciones de puntos cuánticos a base de carbono
(Revistes Catalanes amb Accés Obert, 2022)Los puntos cuánticos a base de carbono muestran propiedades ópticas y electrónicas de interés tecno-lógico debido a su confinamiento cuántico y el efecto de los grupos funcionales en sus bordes. Pueden ... -
Spatial and Temporal Variation of Stable Isotopes in Precipitation across Costa Rica: An Analysis of Historic GNIP Records
(2013-11-27)The location of Costa Rica on the Central American Isthmus creates unique microclimate systems that receive moisture inputs directly from the Caribbean Sea and the Pacific Ocean. In Costa Rica, stable isotope monitoring ... -
Stable isotopes reveal groundwater to river connectivity in a mesoscale subtropical watershed
(Taylor and Francis Ltd., 2021)The Corumbataí River basin (São Paulo, Brazil) has a critical situation regarding water availability due to the intensive use to support agriculture and urbanization, requiring scientific information to face water demand. ... -
Stable isotopic characterizacion of nitrate wet deposition in the tropical urban atmosphere of Costa Rica
(Springer, 2021-07-13)Increasing energy consumption and food production worldwide results in anthropogenic emissions of reactive nitrogen into the atmosphere. To date, however, little information is available on tropical urban environments where ... -
Structure and Properties of Biodegradable Polymers: Rolling Effect in Poly (butylene succinate) Sheets
(SAGE Publishing (Estados Unidos), 2004)Sheets made from poly (butylene succinate) (PBS) were prepared by extrusion. They have been studied under uniaxial drawing as a function of the draw condition. Changes in molecular orientation and crystallinity were ... -
Student Camps to Promote Scientific Vocations in STEM: The Quimi Camp Case
(Universidad Nacional (Costa Rica), 2023-06-01)[Objetivo] Desde el año 1988 y hasta el año 2018, el estudiantado de secundaria en Costa Rica debía aprobar un examen final para graduarse de la escuela secundaria, y ser elegible para una educación universitaria pública. ... -
Synthesis of Dihydroindolo[2,3-c]carbazole as Potential Telomerase Inhibitor
(Journal of Heterocyclic Chemistry vol.53 no.3 762-766 2015, 2015-05-27)The dictyodendrins A-E were the first marine natural products that show inhibition of telomerase. A versatile and convergent route was described for the synthesis of derivatives of these pyrrolo[2,3-c]carbazole alkaloids ... -
The effect of solution environment and the electrostatic factor on the crystallisation of desmotropes of irbesartan
(Royal Society of Chemistry, 2019)The experimental conditions necessary for stabilising irbesartan (IBS) tautomers in solution and selectively obtaining the desmotropic crystal forms are presented herein. 1H and 2H tautomers were stabilized in specific ... -
The manufacture and properties of oil palm and pineapple leaf fiberboard panels
(WIT Transactions on Ecology and the Environment, 2014)Particleboards were manufactured from oil palm fruit, the oil palm mesocarp fiber of Elaeis guineensis, the leaves of pineapple (Ananas comosus) and the sawdust from three fast-growing species of trees (Gmelina arborea, ...