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Soluciones interiores exactas a las ecuaciones de Einstein para un líquido ideal con simetría axial
(2011-07-18)
Exact interior solutions of Einstein equations were obtained, using the ideal fluid model with axial symmetry (Weyl-Lewis-Papapetrou or Weyl-Papapetrou).
Lignanos de Zanthoxylum acuminatum
(2009-01-13)
From the aerial parts of Zanthoxylum acuminatum (Rutaceae) collected in Upala, Alajuela, Costa Rica were isolated the known lignans hinokinin, (+)-asarinin, (+)- piperitol, (+)-kobusin, and epi-kobusin. In addition to 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: ...
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 ...
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 ...
Síntesis y caraterización del ligando tris-(2-tiosalicilamidoetil)amina y sus complejos de hierro e indio
(2009-01-13)
The coordination chemistry of the hexadentate ligand, tris(2-thiosalicylamidoethyl)amine, (LH3), was studied. The reaction of the ligand trianion with iron(III) and indium(III) yields monomeric hexacoordinate complexes, ...
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 ...
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 ...
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 ...
Producción de jarabe de fructosa con enzimas inmobilizadas en un proceso continuo a partir de tiquisque (<i>Xanthosoma sagittifolium</i>)
Producción de jarabe de fructosa con enzimas inmovilizadas en un proceso continuo a partir de tiquisque (<i>Xanthosoma sagittifolium</i>)
(2013-06-28)
High fructose corn syrups (HFCS) are mainly used by the food industry and are produced by enzymatic hydrolysis from cornstarch. The main objective of this project was to produce fructose syrups using tiquisque starch ...