Influences of the solid load on the microstructure and compressive behavior of Fe2O3 scaffolds manufactured by freeze-casting using stearic acid as dispersant agent

Porous materials manufactured by freeze-casting are demonstrating potential application as oxygen carriers for the production and purification of hydrogen, or anode material for lithium-ion batteries. However, to obtain the required pore morphology and sufficient mechanical strength, the suspension processing parameters must be controlled. Fe2O3 nanoparticles/camphene suspensions were fabricated using stearic acid as the dispersant agent showing a low-viscosity (130 mPa⋅s) with a high solid volume fraction (0.3). Suspensions show a shear-thinning behavior according to the Sisko model and a maximum packing fraction of 0.569 estimated from a zero porosity sample. A modified Krieger and Dougherty model was introduced to incorporate the influence of the particleaspect ratio. The Fe2O3 scaffolds manufactured by freeze-casting shown a gradient pore size along the freezing direction, which was diminished with the solid volume fraction, the compression strength was improved with the pore size reduction and fitted according to the minimum solid area model.Universidad de Sevilla PIF II.2AAgencia Estatal de Investigación (AEI) MAT2016-76713-

Protagonismo del mentor en una actividad tutorial de carácter multidisciplinar en Ingeniería

XIX Congreso Universitario de Innovación Educativa en las Enseñanzas Técnicas : Barcelona, 6 a 8 de julio de 2011En la Escuela Politécnica Superior (EPS) de la Universidad de Sevilla se ha trabajado, por tercer curso consecutivo, en un Plan de Acción Tutorial desarrollado por 16 profesores tutores y 20 alumnos mentores de 5 titulaciones de Ingeniería Técnica. El objetivo perseguido en este curso ha sido potenciar actividades que han surgido del propio albedrío de los alumnos mentores, lo que ha dado como resultado la realización de una serie de actividades de mentoría motivadas y dirigidas desde el principio por los alumnos mentores. La actividad conjunta de todos ellos ha llevado a organizar unos subgrupos de mentorías en función de determinadas características del alumnado de primer curso (deportistas, trabajadores, becarios de otras universidades…), a realizar reuniones presenciales de mentores para puesta a punto de estas actividades así como de puesta al día de los resultados que se iban consiguiendo, además de organizar una segunda captación de mentorizados tras las notas del primer cuatrimestre, y la protagonización de una Jornada de Mentoría al final del curso.A third edition with 16 tutorial lecturers and 20 tutorial students from five different degrees (Technical Engineering of the Polytechnical School, EPS, at University of Seville) in a Tutorial Plan development, has been prepared. During the present year, the main characteristic has been a serial of mentoring actions motivated and directed by these mentors. This activity has been organized considering several subgroups of mentoring depending on special characteristics in first year students (sportsplayers, workers, grant holders from other universities…), moreover the organization of a second recruiting of new students after the first term marks, updating meetings for mentors only, and to be main figures in a Congress on Mentoring at the end of the academic year

Type-A Gelatin-Based Hydrogel Infiltration and Degradation in Titanium Foams as a Potential Method for Localised Drug Delivery

A gelatin-based hydrogel was infiltrated and degraded-released in two different titanium foams with porosities of 30 and 60 vol.% (Ti30 and Ti60 foams) and fabricated by the space holder technique to evaluate its potential to act as an innovative, alternative, and localised method to introduce both active pharmaceutical ingredients, such as antibiotics and non-steroidal anti-inflammatory drugs, and growth factors, such as morphogens, required after bone-tissue replacement surgeries. In addition, the kinetic behaviour was studied for both infiltration and degradation-release processes. A higher infiltration rate was observed in the Ti60 foam. The maximum infiltration hydrogel was achieved for the Ti30 and Ti60 foams after 120 min and 75 min, respectively. Further, both processes followed a Lucas-Washburn theoretical behaviour, typical for the infiltration of a fluid by capillarity in porous channels. Regarding the subsequent degradation-release process, both systems showed similar exponential degradation performance, with the full release from Ti60 foam (80 min), versus 45 min for Ti30, due to the greater interconnected porosity open to the surface of the Ti60 foam in comparison with the Ti30 foam. In addition, the optimal biocompatibility of the hydrogel was confirmed, with the total absence of cytotoxicity and the promotion of cell growth in the fibroblast cells evaluated