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Animação estereoscópica: relações entre a tecnologia audiovisual e a percepção da profundidade
(Universidade Federal de São Carlos, 2014-07-30) Santos, Tiago Eugenio dos; Andrade, Leonardo Antônio de; https://lattes.cnpq.br/3921612856948891; https://lattes.cnpq.br/2248690766230203
The stereoscopic application is not in itself a technical novelty, because, already in 1838, the first device that allowed the stereoscopic display is designed. In the early years of its invention new apparatus were constructed in an attempt to combine animation with stereoscopy. The 1910s and 1920s are marked by the beginning of the use of stereoscopy in the cinema and at the end of the 1930s in film animation. Since then, there have been periods of great productivity alternated by periods of relative calm. Today, we live in a time in which stereoscopy comes back to matter in the film scene, especially in animated films. This research builds a historical overview of stereoscopy, stereoscopic cinema and stereoscopic animated film. It also exposes the particularities of a stereoscopic audiovisual piece and discusses the specifics of the application of stereoscopy in animated films. Using as reference periods of stereoscopic film according to the author Ray Zone, this research aims to analyze the use of stereoscopy in animations from different historical periods. The selected works for the analysis are: Motor Rhythm (1952), Starchaser: The Legend of Orin (1985) and Brave (2012). In order to verify the implementation of stereoscopy and the role of parallax in the pieces chosen, an analysis methodology was developed so that we could be able to determine the application of stereoscopy within an audiovisual work while also addressing its narrative composition.
Catalisadores derivados de óxidos do tipo perovskita LaMO3, LaMFeO3 e LaMO3/γ-Al2O3 (M = Co, Ni ou Fe) aplicados à reforma a vapor de etanol
(Universidade Federal de São Carlos, 2014-07-30) Faustino, Patrícia Brígida; Assaf, José Mansur; https://lattes.cnpq.br/9563312407691130; https://lattes.cnpq.br/6807169442685729
The hydrogen production has been extensively studied as a clean and powerful energy source, indicating that in the future hydrogen will became a key component for the global energy production, since burning fossil fuels, used nowadays, emits disturbing amounts of gases that cause the greenhouse effect and the global warming, which urgently needs to be reduced. Thus, hydrogen use has been studied as electric power generation and as a fuel derived from, for example, fuel cells that are able to convert chemical energy from the reaction between H2 and O2 into electrical energy, thermal energy and water, without causing environmental impacts, since it has no noises or vibrations and there is neither combustion or emission of particulates. A feasible way to produce hydrogen is the Steam Reforming Reaction of ethanol, since ethanol is a renewable source obtained mainly from sugar cane and also due to the low costs of operation in the Steam Reforming Reaction. Due to these facts, the reactions of Steam Reforming of Ethanol (SRE) have been extensively studied in previous years, and several studies have shown that this reaction provides a high hydrogen production; however, some parallel reactions may occur, forming side products, leading to reduced amounts of produced H2. Thus, the development of appropriate catalysts in these reactions becomes necessary, in a way that it enhances the conversion favoring the major product and suppressing the conversion to side products. A good efficiency of perovskite type oxides as catalysts in the SRE has been reported in several studies. These materials are mixed oxides with an ABO3 chemical structure, A being the largest cation such as alkali metals, alkaline earth metals and rare earth elements, and B representing the smallest cation such as transition metals. The partial substitution of cations located in the B site by others with similar oxidation state can promote changes in the redox properties of these ions, causing changes in the stability of the crystal structure. Therefore, the perovskite type oxides LaNiO3, LaCoO3 and LaFeO3 were synthesized through the citrate and precipitation methods. In a second stage Fe was added into the structure of the oxides LaNiO3 and LaCoO3, and in a new stage LaNiO3, LaCoO3 and LaFeO3 was synthesized with perovskite type oxides supported on gamma alumina by precipitation-deposition. After the syntheses, the catalysts were characterized and the influence of the preparation method was studied, specifically the effect of Fe addition and of the support presence, in relation to the activity of the catalysts in the reactions of steam reforming of ethanol for hydrogen production. The experimental results showed that the LaCoO3 catalyst synthesized by precipitation method was more active and stable than the others, although the LaNiO3 (citrate and precipitation) and LaCoO3 (citrate) catalysts had also been active in SRE. The material LaFeO3 showed to be inactive in the reaction. The Fe addition in the catalysts LaNiO3 and LaCoO3 structure did not significantly alter their catalytic performance, indicating an economically advantageous feature, since iron is a cheaper metal than cobalt and nickel, and may partially replace these elements in the catalyst formulation, thus decreasing the synthesis cost without compromising the hydrogen yields. The use of gamma alumina as support in the SRE favored materials with higher specific surface area, whereas it did not favor a higher activity or stability of these catalysts, however the activity was maintained.