The electronic properties of the Mg 2 NiH 4 monoclinic phase are calculated using a density functional approach calculation. The crystalline parameters and interatomic distances calculated are close to the experimental values within a 3% error. We also evaluate the density of states (DOS) and character of the chemical bonding for the hydrogen's located in their equilibrium positions. While the Ni-Mg interaction is dominant in the pure alloy, in the hydride the hydrogen atoms present a bonding much more developed with Ni than with Mg. The principal bonding interaction is Ni sp-H s. Moreover, a small bonding between Ni d eg and H 1s is observed. Up the Fermi level, the Ni-H interaction is slightly antibonding. The Mg-Ni bonding interactions are weaker in the hydride phase when compared with the pure Mg 2 Ni alloy. The present study is potentially useful because the alloys Mg-Ni are good materials for hydrogen storage.

Cordoba, C. et al. (2013). Valoración de sistemas ubicuos basados en e-Campus y Near Field Communication en un ambiente universitario.

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The use of the Open edX platform to offer xMOOC courses by different Universities in the world, has led to a growth in the participation of students in the courses, thus generating a set of navigation patterns when interacting with the xMOOC which are recorded in the tracking.log file. So far there is no study that identifies EF-ISF navigation patterns of the set of patterns, for this reason in this document propose the use of the LexRank with Threshold algorithm for the identification of the EF-ISF navigation patterns.