Volumen 21, Números 1 y 2

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  • Ítem
    Sismicidad y fallamiento en la zona de Arenal-Miramar
    (2011-02-01 00:00:00) Fernández Arce, Mario Enrique; Rojas Quesada, Wilfredo; Taylor Castillo, Waldo; Arroyo Hidalgo, Ivonne Gabriela
    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.
  • Ítem
    Variación del estado del mar al paso de las ondas tropicales por el mar Caribe
    (2011-02-07 00:00:00) Sosa-Hurtado, Marina; Hernández, Acacia del Sol
    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.
  • Ítem
    Nanostructure size determination in N+- type porous silicon bY X-Rya diffractometry and Raman Spectroscopy
    (2011-02-07 00:00:00) Ramírez Porras, Arturo
    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.
  • Ítem
    Control de calidad en espectrometría gamma de bajo nivel
    (2011-02-07 00:00:00) Salazar Matarrita, Alfonso; Loría Salazar, Luis Guillermo
    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.
  • Ítem
    Odontología en el Renacimiento Español: la práctica profesional
    (2011-02-07 00:00:00) Guzmán Stein, Miguel
    Until the publication of the book Coloquio... Sobre la materia de la dentadura, y maravillosa obra de la boca by Franco Martínez del Catrillo in 1557, the dental subjet was relegated to an inferior plane below Medicine and Surgery as well in the Antique, but particularly during the Middle Age in the cristian world, with their strong consequences among the human beings. This article study the transition from Middle Age to the Enlightment in Spain through the development of the dentistry thoery and praxis as a part of the surgery skills, and it pointed the Coloquio... as a master piece of innovation, trascending it throughout Europe, not only as a medicne speciality but also influencing the culture and hygiene at that time. Some remarks at the end the book gives a brief selection of contents of others treatise on medicine and general surgery, particularly on dental and buccal treatment. For the elaboration for this study original bibliographics sources were consulted in situ that are keeped by the National Library of Madrid, also section of Science and Medicine in the Library of the University of Zaragoza, and others libraries in Spain and Europe.