Listar Revista de Ciencia y Tecnología por título
Mostrando ítems 10-29 de 79
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Calculations of chemical equilibrium with symbolic computation
(2014-07-07)We show how a processor for symbolic computation can readily enable extensive calculations to describe the equilibria involving gases, the pH of an aqueous solution in the titration of a polyprotic acid, and complex ions ... -
Caracterización del producto del proceso de viscoreducción, para la conversión de aceite vegetal, aceite de alga y búnker
(2013-06-28)Through the use of a high pressure and high temperature reactor conditions a visbreaking is simulated, with the purpose of producing green fuels, replacing a fraction fuel oil #6 with vegetable oils. A 25% (m/m) of palm ... -
Caracterización y determinación del potencial Aterogénico de quesos producidos en Costa Rica
(2009-01-13)Cardiovascular diseases have been one of the main causes of mortality during the past years in Costa Rica. Many risk factors associated to these disorders include the intake of high-fat diets, being cheese an example of ... -
Cálculo de las integrales radiales en dispersión de electrones
(2011-02-11)The radial integrals which arise from the distorted wave treatment of photon emission process in electron and positron scattering, involve products of the electron`s (or positron`s) ingoing and outgoing wave functions and ... -
Ciencia, tecnología y educación en Costa Rica en el período 2010-2014
(2017-09)En este artículo se analizaron las distintas redes vinculadas a la formulación de políticas públicas en la Comisión de Ciencia y Tecnología del Congreso de Costa Rica, entre el 2010 y 2014, con el propósito de describir ... -
Climatología del viento y oleaje frente a las costas de Costa Rica, parte 1.
(2009-04-29)The climatologically behavior of the wind and waves is studied around the Costa Rica's coasts using re-analysis data from wave forecasting numeric model. It is found that the wind in the Caribbean coasts of Costa Rica is ... -
COMPARACIÓN DE METODOLOGÍAS DE EXTRACCIÓN PARA LIMONENO Y CARVONA EN Lippia alba USANDO CROMATOGRAFÍA DE GASES.
(2012-11-26)Abstract Different plants drying procedures, hydrodistillation and solvent extraction by sonication were evaluated for the essential oil extraction of Lippia alba. Quantitative ... -
Control de calidad en espectrometría gamma de bajo nivel
(2011-02-07)Low level gamma spectrometry is a very precise techniqueto measure the concentration of nuclides present in different samples in Bq kg-1. The quality control of the procedure and method used be carried out by intercomparison ... -
Curvatura en teorías generalizadas de Yang-Mills
(2009-01-13)The curvature in R1+3 spaces with a generalized Yang-Mills connection is studied and the results are analyzed. Other options borne by modifications of the base space are also studied and commented. The present situation ... -
Desórdenes del sistema musculoesquelético por trauma acumulativo en estudiantes universitarios de computación e informática
(2011-07-18)The main objective of this research was to establish the correlation of Musculoskeletal Disorders (MSD ́s) by accumulative damage, among university ́s students from the computer science school (ECCI) at the Universidad de ... -
Determinación de un modelo para el consumo de energía con suspensión total de sólidos en fluidos newtonianos
(2011-07-18)The development of a model for the power consumption in a mixing process for the suspension solids in a Newtonian liquid is proposed in this study. As a first step of this research, the critical variables were determined ... -
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 ...