Listar Revista de Ciencia y Tecnología por título
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Direct functionalization of Mn12-(methacrylate) clusters on Si(100): surface characterization and electrochemical properties
(2016-09)The reaction of H–terminated Si(100) with methacrylate–substituted manganese carboxylate clusters [Mn12O12{CH2C(CH3)COO}16(H2O)4], [Mn12–(methacrylate)] via hydrosilylation afforded Mn12–(methacrylate)−Si(100). The chemically ... -
Diseño, construcción y puesta en marcha de un fotobiorreactor tubular para producir la microalga Chlorella sp.
(2015-06-17)The following is an article about the design and construction of a tubular photobioreactor to produce microalgae Chlorella sp. using combustion gases from a fuel-oil boiler. The reactor was build for the treatment of 50 L ... -
EEfecto de contaminantes sobre la transferencia de oxígeno en sistemas de aeración analizado mediante un modelo de dos zonas simplificado
(2009-01-13)A series of unsteady-state reaeration tests were performed in a 1000 l tank at 1-10-3 normal m3/s diffused-air flow rate and 298,65 K water temperature. Three different types of impurities: soybean oil, surfactant, and ... -
Emisiones antropogénicas de compuestos tóxicos para el aire en el Gran Área Metropolitana de Costa Rica en el 2007
(2015-06-17)The Emissions Inventory Toxic Air Compounds for the Greater Metropolitan Area in 2007 is framed within the air quality policy in Costa Rica. The main toxic anthropogenic contaminants were toluene, methanol, xylenes, ... -
Estructura hidrográfica de la Bahía de Bluefields, Nicaragua
(2009-04-29)In March and October of 2000, under the DIPAL II project (Proyecto para el Desarrollo Integral de la Pesca Artesanal en la Región Autónoma del Atlántico Sur), two hydrographic surveys were carried out in the Bay of Bluefields ... -
Estudio de una definición no aritmética de finitud conjuntista
(1987)Intuitivamente, un conjunto es finito si termina quedando vacío al extraerle elementos de uno en uno. El propósito de este trabajo es formalizar esta noción de finitud conjuntista y discutir algunas propiedades que se ... -
Evaluación de la uniformidad intrínseca en gamma cámaras del servicio de medicina nuclear del Hospital San Juan de Dios
(2009-04-29)The quality assurance program in a Nuclear Medicine Department aims to minimize errors and artifacts that cover all aspects of clinical practice. The quality control can be seen such as one particular procedure used to ... -
Evaluación de las aguas de drenaje del sector de riego de Tamarindo y su influencia sobre el Parque Nacional Palo Verde
(2011-07-18)The following physicochemical parameters were measured to determine the quality of the drainage water of Tamarindo Irrigation Sector, at the Arenal-Tempisque Irrigation District: temperature, pH, dissolved oxygen saturation ... -
Evaluación y desarrollo de la metacognición en la enseñanza de la química
(2011-07-18)Metacognition may be defined as the knowledge and regulation of one’s own cognitive system, the capacity to reflect about one’s actions and thoughts. Current views on metacognition pose it as a fundamental factor in achieving ... -
Evaluation of three chroroplastic markers for barcoding and for phylogenetic reconstruction purposes in native plants of Costa Rica
(2012-11-26)DNA barcoding has been proposed as a practical and standardized tool for species identification. However, the determination of the appropriate marker DNA regions is still a major ... -
Una fundamentación instrumental de la Aritmética
(1990)Desde el punto de vista de la génesis histórica y psicológica del conocimiento humano, poca duda cabe que los números naturales van siendo elaborados como referente social en el proceso de conteo. En este artículo se ... -
Graph Theory and simple Hueckel Theory applied to benzene
(2012-11-26)We compare the results of application of graph theory and of simple Hueckel theory in its traditional form to benzene, as an instance of a conjugated molecular system. The ... -
Harnessing titanium dioxide surface toward novel functional materials
(2015)The ever-increasing worldwide energy consumption has led the society to quest for novel and functional materials that can be used in the development of solar fuels to some extent lessen the dependence on fossil fuels. In ... -
Historia del campo geomagnético de Costa Rica
(2011-02-15)The study of the geomagnetic field began with the publication of the book De Magnete (1600) of Sir William Gilbert (1504-1603). By influence of Sir Edmund Halley the British Marine is obligated to make measurements of the ... -
Identificación de modelos de orden reducido a partir de la curvatura de reacción del proceso
(2009-01-13)A general identification procedure is given, for first and second orders plus time delay models, that uses two or three arbitrary points over the process reaction curve. Two simplified versions of the methods are described: ... -
IMPACTO DEL CRECIMIENTO ECONÓMICO INDUSTRIAL SOBRE LOS RECURSOS ENERGÉTICO E HÍDRICO EN COSTA RICA
(2012-11-26)An empirical relationship between water consumption, energy consumption and industrial GDP was established, for the case of Costa Rica. This relationship may be useful in ... -
Importancia de la batimetría de las planicies basales en la propagación de tsunamis transoceánicos
(2009-04-29)The initial form of a tsunami originated by an homogeneous seismic source consists on a simple wave front. While the tsunami propagates in deep water, this simple form suffers several modifications by the tsunami's interaction ... -
Kinetics of the fischer esterification of palm fatty acids with isopropanol and butyl-cellosolve
(2009-01-13)Fischer esterification of the mixture of palm fatty acids can be achieved in 80% conversion, under conditions of reactive distillation and methanesulphonic acid as catalyst. The volatility of the H2O/alcohol azeotrope ... -
La cinética de la esterificación de ácidos carboxílocos es de segundo orden con repecto al alcohol
(2009-01-13)Esterification of carboxylic acids with alcohols is considered as AAC2 type reaction. The specific rate of esterification of acetic acid with methanol, in mixtures of acetonitrile-methanol showed a quadratic dependence on ... -
La lógica difusa en ingeniería: principios, aplicaciones y futuro
(2009-01-13)Fuzzy logic is a mathematical tool that mimics the way humans manage and process information. It is a method of great simplicity for processing of information, decision making and process control. This article discusses ...