The aim of this work was to use the Washburn capillary rise method to evaluate changes in surface energy promoted by the insertion of CuO in a 58S glass and its implication in bioactivity. The presence of CuO decreased the surface wettability by decreasing the Lewis acid-base component γ S AB and increasing the Lifshitz-van der Waals component γ S LW . The insertion of CuO also diminished the value of the electron donor parameter γ S -; i.e., the number of negative groups. This was accompanied by a nonuniform apatite formation on the surface, likely because the presence of CuO-rich regions with lower electron donor values impaired the adsorption of Ca 2+ , preventing uniform apatite precipitation. Therefore, surface energy was extremely sensitive to small physical and chemical changes in the glass structure and the behavior of the electron donor parameter could be used as an adequate probe to predict glass bioactivity.

In this work aqueous-based tape casting was used to produce Ni-GDC substrates. Rheological properties of the slurries were measured at room temperature. The acrylic-based suspensions showed a pseudoplastic behavior and remained stable and homogeneous. Tapes with thickness between 100 and 220 um were produced and showed smooth and homogeneous surfaces and good flexibility. Sintered tapes showed good density and porosity values.

<p>Este trabalho tem como objetivo analisar as propriedades microestruturais, físicas, mecânicas e elétricas de compósitos NiO-CDG obtidos pela técnica <em>tape casting</em> e sinterizados em diferentes temperaturas. Os resultados revelaram que os compósitos têm fases cristalinas bem definidas de óxido de níquel (NiO) e céria dopada com gadolínio (CDG). As amostras sinterizadas a 1400 ºC apresentaram a melhor relação entre densidade relativa (98,00 %) e resistência mecânica (107,39 MPa). Além disso, amostras a verde mostraram uma resposta elétrica semelhante às sinterizadas, tornando-as excelentes candidatas para aplicações como materiais precursores de ânodos para células a combustível de óxido sólido (SOFCs).</p>

Studies have been developed in last decades in order to produce NiO-based material to be used as anode in solid oxide fuel cell (SOFC). Aqueous-based tape casting was used to produce NiO-GDC substrates with smooth and homogeneous surfaces and good flexibility. Physical and mechanical properties were obtained in green tapes sintered at temperatures ranging from 1200 to 1400 ͦ C. The tapes sintered in 1400 ͦ C showed the best density and porosity values and mechanical strength between 7 and 25 MPa. SEM micrographs show a dense material with cracks and pores. The sintered material shows the presence of nickel oxide and gadolinium cerium oxide.

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