930 resultados para Alonso de Espina


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Tesis (Doctor en Ciencias con acentuación en Química de Productos Naturales) UANL, 2014.

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Dans une société médiatique on ne peut pas définir l’intellectuel comme une personne qui simplement travaille avec les lettres; on doit le définir plutôt comme une personne qui utilise d’autres moyens de communication en cherchant la meilleure façon de critiquer la société. En regardant la problématique de la définition de l’intellectuel dans la société médiatique on étudie dans ce mémoire les films Rodrigo D. No futuro et La Vendedora de Rosas réalisés dans les bidonvilles de Medellin par le directeur colombien Víctor Gaviria. Dans les films on peut voir la vie de jeunes garçons et des enfants pour qui la réalité est faite de drogue et de pauvreté. L’étude s’étend sur trois chapitres : Dans le premier on examine l’ensemble socio-historique dans lequel les films ont été réalisés et aussi on examine le concept de « sicariato » qui a été utilisé dans des études scientifiques et des romans. Le second chapitre porte sur la problématique de la définition de l’intellectuel et sur le processus de création de Víctor Gaviria, appelé « Voluntad Realista ». Dans le troisième chapitre on examine le manifeste écrit par Víctor Gaviria « Las Latas en el fondo del río » dans le contexte historique du troisième cinéma latino-americain, dont les cinéastes ont écrit des manifestes semblables.

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Thèse diffusée initialement dans le cadre d'un projet pilote des Presses de l'Université de Montréal/Centre d'édition numérique UdeM (1997-2008) avec l'autorisation de l'auteur.

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Màster Oficial en Enginyeria Biomèdica

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A deformed-jellium model is used to calculate the fission barrier height of positive doubly charged sodium clusters within an extended Thomas-Fermi approximation. The fissioning cluster is continuously deformed from the parent configuration until it splits into two fragments. Although the shape of the fission barrier obviously depends on the parametrization of the fission path, we have found that remarkably, the maximum of the barrier corresponds to a configuration in which the emerging fragments are already formed and rather well apart. The implication of this finding in the calculation of critical numbers for fission is illustrated in the case of multiply charged Na clusters.

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Slab and cluster model spin-polarized calculations have been carried out to study various properties of isolated first-row transition metal atoms adsorbed on the anionic sites of the regular MgO(100) surface. The calculated adsorption energies follow the trend of the metal cohesive energies, indicating that the changes in the metal-support and metal-metal interactions along the series are dominated by atomic properties. In all cases, except for Ni at the generalized gradient approximation level, the number of unpaired electron is maintained as in the isolated metal atom. The energy required to change the atomic state from high to low spin has been computed using the PW91 and B3LYP density-functional-theory-based methods. PW91 fails to predict the proper ground state of V and Ni, but the results for the isolated and adsorbed atom are consistent within the method. B3LYP properly predicts the ground state of all first-row transition atom the high- to low-spin transition considered is comparable to experiment. In all cases, the interaction with the surface results in a reduced high- to low-spin transition energy.

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The chemical properties of single-atomic chains of gold atoms are investigated using density functional calculations. The nanochains are shown to be unusually chemically active with strong chemisorption of oxygen atoms and carbon monoxide. The chemisorption energies vary significantly with the strain/stress conditions for the chain. Oxygen atoms are found to energetically prefer to get incorporated into a chain forming a new type of gold-oxygen nanochain with a conductance of one quantum unit. We suggest that the long bond lengths observed in electron microscopy investigations of gold chains can be due to oxygen incorporation.

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The mechanism of generation of atomic Na and K from SiO2 samples has been studied using explicitly correlated wave function and density functional theory cluster calculations. Possible pathways for the photon and electron stimulated desorption of Na and K atoms from silicates are proposed, thus providing new insight on the generation of the tenuous Na and K atmosphere of the Moon.

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The interface of MgO/Ag(001) has been studied with density functional theory applied to slabs. We have found that regular MgO films show a small adhesion to the silver substrate, the binding can be increased in off-stoichiometric regimes, either by the presence of O vacancies at the oxide film or by a small excess of O atoms at the interface between the ceramic to the metal. By means of theoretical methods, the scanning tunneling microscopy signatures of these films is also analyzed in some detail. For defect free deposits containing 1 or 2 ML and at low voltages, tunnelling takes place from the surface Ag substrate, and at large positive voltages Mg atoms are imaged. If defects, oxygen vacancies, are present on the surface of the oxide they introduce much easier channels for tunnelling resulting in big protrusions and controlling the shape of the image, the extra O stored at the interface can also be detected for very thin films.

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Se presenta experiencia educativa que propone la elaboraci??n de materiales para dar respuesta a la diversidad de alumnado. Se realiza en el IES Veleta en Granada. Los objetivos son: crear unos materiales que estuvieran adaptados a los niveles de nuestros alumnos; crear unos materiales que cubrieran las necesidades, motivaciones e intereses de nuestros alumnos; facilitar a nuestro alumnado la adquisici??n de los conocimientos m??nimos exigidos en el curr??culo; agrupar los materiales resultantes en tres ??mbitos para facilitar la labor docente y el proceso de ense??anza-aprendizaje de nuestro alumnado; fomentar un mayor conocimiento de la lengua espa??ola y la ampliaci??n de su l??xico para conseguir en nuestro alumnado una expresi??n m??s fluida; utilizar el material elaborado en situaciones reales dentro del aula; dar respuesta a una situaci??n cambiante dentro de nuestras aulas; facilitar la labor a los docentes para dar una respuesta m??s r??pida y efectiva en el contexto cambiante de nuestras aulas; fomentar el conocimiento y la apreciaci??n de la cultura espa??ola valorando el respeto y la opini??n de los dem??s; crear un ambiente de trabajo relajado pero activo y responsable; fomentar la autonom??a de nuestro alumnado en su proceso de ense??anza-aprendizaje; propiciar la participaci??n activa de los alumnos en las clases; motivar el esfuerzo, razonamiento l??gico y autonom??a del alumnado, trabajando en clase casos y problemas de la vida cotidiana.

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Monográfico con el título: 'Competencias Educativas'. Resumen basado en el de la publicación

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Monográfico con el título: 'Igualdad y Coeducación, hacia la libertad individual y la convivencia'. Resumen basado en el de la publicación