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A process for obtaining planar anode-supported solid oxide fuel cells was developed. Aqueous-based slurries were prepared and sequentially deposited via tape casting to form half cell tapes consisting of the electrolyte, functional, and structural anode. Sintering of the three-layered tapes was done in two stages: presintering circular samples of 25 mm diameter in free conditions first, and then sintering them using zirconium disks as light loads (90 Pa), to obtain half cells having 20 mm and 3.8 m À1 in diameter and curvature, respectively. Active materials for the electrolyte, anode, and cathode were partially stabilized zirconia (PSZ), Ni and LSM, respectively. Finally, thicknesses of complete cells were 400, 30, 30, and 80 lm for the structural anode, functional anode, electrolyte, and cathode, respectively. The cells were tested in a no-chamber (direct-flame) setup evaluating electrochemical performance and shock thermal resistance. Open circuit voltage was 830 mV at 560°C using methanol as fuel in a burner with porous media to modify the shape of the flame. Cells were also strong enough to resist the rapid temperature changes during several no-chamber tests.

En este trabajo se evaluaron los ensayos para la obtención de azúcares fermentables a partir de materias amiláceas, en este caso particular yuca, los cuales comprendieron el seguimiento de la reacción de hidrólisis enzimática para la posterior determinación de la cinética de reacción (formación de producto en función del tiempo). En una primera etapa se consideró el proceso convencional que consta de licuefacción y sacarificación, a cargo de una alfa-amilasa y una gluco-amilasa comerciales respectivamente. Yen una segunda etapa la acción bifuncional de una única enzima comercial, analizándose por separado las dos partes constitutivas de la yuca: el parénquima interno y el parénquima externo. La materia prima se caracterizó en cuanto a su composición, porcentaje de humedad, proteína y por último contenido de almidón enbase seca.