Volumen 21, Números 1 y 2
https://hdl.handle.net/10669/14600
2024-03-29T10:37:37ZSismicidad y fallamiento en la zona de Arenal-Miramar
https://hdl.handle.net/10669/14605
Sismicidad y fallamiento en la zona de Arenal-Miramar
A review of the local tectonic frame was made, focusing on the faulting of The Tilaran Ridge and Montes de Aguacate. On a map of faults we plot historic and recent seismicity which was taken from Rojas (1993) and data bases of The National Seismological Network (RSN:ICE-UCR) and The Arenal Seismic Network (ICE). We verified that there is active faulting both north and south of Arenal Lake. The main faults with associated seismic activity are Jamaical, Esperanza, Cote-Arenal, Caas, those of a system parallel to Arenal Lake and those toward north-northeast of Esparza. In the area tow large historic earthquakes have ocurred, one of wich killed 23 people.; Se realizó una revisión de los trabajos que existen sobre tectónica a nivel local, analizando las diversas fallas documentadas en el área de las estribaciones montañosas correspondientes a la Cordillera de Tilarán y a los Montes del Aguacate. Sobre un mapa de fallas se graficó la sismicidad extraída de las bases de la Red Sismológica Nacional (RSN: ICE-UCR), del catálogo y del Observatorio Sismológico del Volcán Arenal (OSIVAM-ICE). Se comprueba que hay fallamiento activo en la zona tanto al corte como al sur del embalse de Arenal y las principales fallas con actividad sísmica asociada son: Jamaical, Esperanza, Cote-Arenal, Cañas, un sistema al norte del embalse de orientación noroeste y otro al norte de Esparza. En esta área sísmica han ocurrido dos grandes sismos históricos, uno de los cuales causó la muerte de 23 personas.
2011-02-01T00:00:00ZVariación del estado del mar al paso de las ondas tropicales por el mar Caribe
https://hdl.handle.net/10669/14604
Variación del estado del mar al paso de las ondas tropicales por el mar Caribe; Variación del estado del mar al paso de las ondas tropicales por el mar Caribe
The Caribean sea is considered as great maritime traffic zone and one of the seas adjacent to Cuba for which the weather forecast everyday are issued. In summer, the tropical wave cross through this region, bringing the increase in wave. In current paper, the wave height variation during the passage of these weather systems through Caribbean sea was studied. Also the result obtained will be usefull to improve the maritime forecast`s quality.; El mar Caribe es una zona de gran tráfico marítimo y uno de los mares adyacentes a Cuba para los cuales se confeccionan cada día pronósticos del tiempo. En verano, con frecuencia cruzan por el lugar ondas tropicales que incrementan el oleaje. El presente trabajo investiga la variación de la altura de la ola de estos sistemas por el mar Caribe y sus resutados servirían para mejorar la calidad de los pronósticos marítimos.
2011-02-07T00:00:00ZNanostructure size determination in N+- type porous silicon bY X-Rya diffractometry and Raman Spectroscopy
https://hdl.handle.net/10669/14603
Nanostructure size determination in N+- type porous silicon bY X-Rya diffractometry and Raman Spectroscopy
A series of porous silicon surfaces were obstained after different exposition times of electrochemiscal etching on crystaline n+- type silicon in presence of hydrofluoric acid. These kind of surfaces show photoluminescence when illuminated by UV light. One possible explanation for this is that the treated surface is made up of small crystallites in the nanometer scale that split away the semiconductor band edges up to optical photon energies for the band-to-band recombination processes. In this study, a nanometer size determination of such proposed structures was perfomed by use of X-Ray Diffractometry and Raman Spectroscopy. The results suggest a consistency between the so called Quantum Confined Model and the experimental results.
2011-02-07T00:00:00ZControl de calidad en espectrometría gamma de bajo nivel
https://hdl.handle.net/10669/14602
Control de calidad en espectrometría gamma de bajo nivel
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 exercises with world reconized institutios. During the last three years the Nuclear Physics Laboratory of the University of Costa Rica (LAFNA) has been participating in the international quality assessment program (QAP) carried out by the Environmental Measurements Laboratory (EML), Department of Energy, USA. The results show a very good agreement with the rest of the participant laboratories. This provide a very objetive evaluation of the high precision of the methods used by LAFNA in low leel spectroscopy measurements.
2011-02-07T00:00:00Z