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Niveles de radioactividad en tres regiones de Costa Rica
Niveles de radioactividad en tres regiones de Costa Rica
(2011-02-15)
The establishment of the first radioactivity levels of natural radiation was carried out during the period 1991 to 1994 in three different regions of Costa Rica. The radionuclides studied belong to different soil types ...
Acerca de si pudo o no ser el universo anisotrótipico
Acerca de si pudo o no ser el universo anisotrótipico
(2011-02-15)
The theoretical and experimetnal problem concerning the origin and formations of the universe is establish in this paper, specially by developing some theories that try to explain this phenomena, and also to settle the ...
Álgebras-MV artinianas y noetherianas
Álgebras-MV artinianas y noetherianas
(2011-02-11)
We study MV-algebras that satisfacy tha ascending of descending chain conditions on ideals. We demostrarted, for example, if an MV-algebra is artianan, then it has a finite number of minimal prime ideals. We also show the ...
Álgebras-MV artinianas y noetherianas
(2011-02-14)
Estudiamos álgebras-MV que satisfacen las condiciones de cadena ascendente o de cadena descendente por ideales. Por ejemplo, si un álgebra es artiana, entonces tiene un número finito de ideales primos y minimales. También ...
Sismicidad y fallamiento en la zona de Arenal-Miramar
(2011-02-01)
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 ...
On the classification of constrained extrema
(2011-07-18)
Using simple arguments, accessible to students of advanced calculus with an interest in Mathematics, we show the equivalence of several criteria, scattered in the literature, to classify the critical points of functions ...
COMPARACIÓN DE METODOLOGÍAS DE EXTRACCIÓN PARA LIMONENO Y CARVONA EN Lippia alba USANDO CROMATOGRAFÍA DE GASES.
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 ...
Polymers of unidimentional coordination [M(sac)2(H2O)(pyz)]n, (M= Ni2+, Cu2+ and Zn2+, sac =saccharinate, pyz= pyrazine), spectroscopy and magnetic properties
(2011-07-18)
Coordination polymers have been prepared by the hydrothermal reaction of M2+saccharinates (M = Ni, Cu and Zn) and pyrazine, pyz, in a ratio 1:1. The complexes of formula [M(sac)2(H2O)2pyz]n, M = Ni2+ and Zn2+ and ...
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 ...
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 ...