Propuesta de un nuevo modelo de prácticum en el título de Grado de Maestro de Primaria de la Universidad de Alicante

Comunicación presentada en el XI Symposium Internacional sobre el practicum y las prácticas en empresas en la formación universitaria "Evaluación y supervisión del practicum: el compromiso con la calidad de las practicas", Poio (Pontevedra), 27-29 junio 2011.

KOH activation of carbon materials obtained from the pyrolysis of ethylene tar at different temperatures

A complete study of the importance of the pyrolysis temperature (up to 1500 °C) of a petroleum residue (ethylene tar) in the activation with KOH of the resultant pyrolysis products (covering from the own ethylene tar to pitches and well developed cokes) has been carried out. The trend in the porosity found for activated carbons is as follows: the pore volume increases with the pyrolysis temperature reaching a maximum value (1.39 cm3/g) at about 460 °C, just at the transition temperature between a fluid pitch and a solid coke. It is the pitch with highest mesophase content that develops the maximum porosity when activated with KOH. The amount of H2, CO and CO2 produced during the reaction of the mesophase pitch and coke with KOH has been quantified, and a trend as described for the pore volume was found with the pyrolysis temperature. Therefore, there is a relationship between the reactivity of the precursor with KOH and the porosity developed by the activated carbon. Since the reactions that produce H2 initiate at temperatures as low as 300 °C, it seems that KOH is modifying the conditions under which the pyrolysis occurs, and this fact is critical in the development of porosity.

Preparation of high metal content nanoporous carbon

Activated carbons with high metal content have been prepared by the pyrolysis of ethylene tar with dissolved metal acetylacetonates (Ti, V, Fe, Co, Ni and Cu) and subsequent activation with KOH of the pitch obtained in pyrolysis. These metal compounds decompose during the pyrolysis of ethylene tar yielding metal nanoparticles formed by metal and/or oxide which are homogeneously distributed in the pitch and remain in the activated carbon, so that the concentration of metal is, in most cases, 4–5 times higher than in the pristine ethylene tar. Since KOH is an effective activating agent, all activated carbons combine a high porosity development with a high metal content. In some of the carbons, such as P2FeA (3.3% Fe, pore volume 1.84 cm3/g, BET surface area 3270 m2/g), there is even an increase in the pore volume when compared to the activated carbon prepared in the same way without metal, in spite of the fact that the metal increases the weight of carbon without contributing to the adsorptive capacity. It seems that iron, on the one hand modifies the pyrolysis to give a pitch with larger mesophase content and on the other hand it locally catalyzes carbon gasification with the CO2 produced along the synthesis of the carbon. In addition to its influence on activation, iron promotes the formation of graphitic carbon fibers.

Características de los ambientes de aprendizaje online para una práctica docente de calidad. Indicadores de evaluación

Contribuir a la mejora de la calidad de la enseñanza y de los resultados de aprendizaje constituye uno de los retos en el sistema universitario actual que exige un gran esfuerzo de coordinación en las acciones de investigación e innovación a desarrollar. Para alcanzar este propósito, desde el grupo de investigación EDUTIC-ADEI (VIGROB-039) de la Universidad de Alicante se ha promovido la constitución de una red docente interdepartamental e interuniversitaria que pretende investigar sobre cómo debe ser la enseñanza online que se desarrolla en el ámbito universitario. Para ello, se ha abordado el concepto de ambiente de aprendizaje en este contexto virtual con el fin de delimitar los parámetros que deben definir una enseñanza de calidad cuando hablamos de e-learning, Masive Open Online Courses [MOOCs], Personal Learning Environment [PLE], etc. La investigación, pues, ahonda en los aspectos curriculares que conforman dichos ambientes de aprendizaje online con el fin de delimitar los parámetros de una enseñanza virtual de calidad.