Navegando por Data de Publicação, começando com "2013-10-17"

Filtrar resultados por ano ou mês

Agora exibindo 1 - 4 de 4

Desenvolvimento de método analítico por cromatografia líquida para determinação de impurezas no iodixanol
(Universidade Federal de São Carlos, 2013-10-17) Rondon, Bruno Doratioto; Cass, Quezia Bezerra; https://lattes.cnpq.br/9197210255594409
This work describes for the first time an isocratic method in a single analytical run to quantify deacetyl iodixanol (iodixanol related compound C), iopentol (iodixanol related compound D) and cyclized iodixanol (iodixanol related compound E), as impurities in iodixanol. Iodixanol is a drug substance, dimeric, nonionic, water-soluble, used as a radiographic contrast medium, which is administered by intravascular injection. The impurities A and B were not evaluated in this work, since they are not commercially available as standards. The method was also validated for the quantitative assay, since there is no chromatographic method described in the current USP compendium for the assay. The impurities can be formed during the synthesis process of iodixanol, and it is important to quantify them due to their related toxicity. In this work, the reverse and hydrophilic interaction (HILIC) modes of elution were evaluated. The hydrophilic elution mode was selected due to good efficiency and selectivity. In both modes of elution, columns having the technology fused-core were used, since they demonstrate high efficiency due to their better mass transfer in comparison to conventional HPLC columns. The chromatographic separation was carried out on a kinetex® HILIC column (150 x 4.6 mm; 2.6 μm) at 20 °C using acetonitrile-formic acid (pH 3.2; 1.0 mmol L-1) (92:08, v/v) at a flow rate of 0.8 mL/min. The compounds were monitored at 243 nm and the total time of analysis was 45 min. The method was validated in accordance with the current ICH guidelines for determination of impurities which include selectivity, linearity, accuracy, precision, limits of quantification and detection and robustness. The limits of quantification (LOQ) were 0.479; 0.0606 and 0.133 μg/mL for the impurities C, D and E, respectively. Furthermore, the validated methods were tested in iodixanol samples. The test results of the analyses of impurities and assay in those samples are presented and discussed accordingly.
A construção de mundos online: uma análise da comunidade de fãs de Lost, Darkufo
(Universidade Federal de São Carlos, 2013-10-17) Trento, Francisco Beltrame; Massarolo, João Carlos; https://lattes.cnpq.br/3308336910966465; https://lattes.cnpq.br/6399881805812837
This dissertation aims to analyze the world-building process as spaces of transmidiatic communication. We listed information from the distinct media utilized on the development of the TV series Lost, including it internal narrative complexity. We studied and classified distinct factors that congregated the user interaction in an online community. We investigated the conditions of meaning production and the discursive and ideological formations enounced in a complex system of communicational interaction. We also observed how the authorfunction acts in collaborative ambient from the web 2.0. This research is qualitative and exploratory, and examines the Darkufo online community, constituted by users that were fans of the TV-series Lost. Based on the netnographic methodology and using the discourse analysis studies, we tried to systematize the processes that involve users and the online community interactive ambient.
Produção de hidrogênio por reforma a vapor e oxidativa do etanol utilizando óxidos do tipo perovskita
(Universidade Federal de São Carlos, 2013-10-17) Garcia, Silmara Rodrigues; Assaf, José Mansur; https://lattes.cnpq.br/9563312407691130; https://lattes.cnpq.br/8510190431071866
This paper assesses the catalytic activities of LaCoO3 perovskite towards the steam reforming oxidative reaction of ethanol . Due to the low surface area which is commonly found on perovskite-type oxides , these were supported onAl2O3 , ZrO2 and ZrO2-Al2O3. The unsupported catalysts were prepared by precipitation and citrate methods whilst the supported catalysts were prepared by deposition -precipitation . The techniques employed to characterize the solids were: X -ray diffraction by the powder method (DRX) , X-Ray Fluorescence (FRX) Programmed Temperature Reduction with H2 (RTP-H2) Nitrogen Adsorption by B.E.T. method, X-ray Diffraction in situ, Raman spectroscopy, transmission electronic microscopy, scanning electronic microscopy, hydrogen desorption at programmed temperature TPD-H2 and Thermogravimetric Analysis. The preparation of the catalysts by precipitation and citrate routes proved to be efficient to obtain the perovskite type oxides .The supported catalysts showed surface area values larger than the unsupported ones, as there was the formation of other oxidase phases due to stand- perovskite or metal support interactions , as observed by the decreasing of reduction degree , through RTP analysis .The unsupported catalysts calcined at 700 , 800 and 900 ° C presented the best activity for oxidative reforming reaction than the supported ones. These, in turn, showed better catalytic activity towards the oxidative reforming reaction in relation to steam reforming of ethanol. By the X-ray Diffraction analysis in situ performed during the RTP-H2 and reaction tests, it was observed that the 20LaCoO3/Al2O3 catalyst prepared by method 2 - deposition -precipitation - showed lower size of crystallite of cobalt during the steam reforming reactions and oxidation in situ, therefore suggesting a better metal dispersion . The unsupported LaCoO3 catalyst prepared by precipitation method and calcined at 700ºC showed less coke formation towards the oxidative reaction of reforming of ethanol . Among the supported compounds the 20LaCoO3/ZrO2 showed the lowest coke formation in the same reaction. The analysis of scanning electron microscopy performed after the oxidative reaction, Raman spectroscopy the and Thermogravimetric Analysis, suggests that the unsupported LaCoO3 catalyst prepared by precipitation and calcined at 700ºC and the supported 20LaCoO3/ZrO2 catalyst showed lower carbon formation.
Projeto Canadá: seletividades e redes de imigrantes brasileiros qualificados em Toronto
(Universidade Federal de São Carlos, 2013-10-17) Sega, Rodrigo Fessel; Truzzi, Oswaldo Mário Serra; https://lattes.cnpq.br/5005536921435787; https://lattes.cnpq.br/1375808875370802
The focus of this work is Brazilians who migrated to the city of Toronto, Canada, through government programs to attract skilled labor from the Canadian government. This dissertation examines the relationship between skilled migration and social networks from fieldwork conducted in the city of Toronto between December 2011 and June 2012. Sought to understand how the migration process occurs, as potential migrants are actual migrants, from analyzing the decision to migrate and move to Toronto to adaptation processes in the destination society. From ethnography, participant observation and semistructured interviews with these Brazilian immigrants, we see how the internet and communications technologies are important mediators of this process, the creation of social networks and integration in existing networks. The profile of skilled labor bounded by the Canadian government was also analyzed in comparison to the profile of Brazilians who actually migrate, generating different modes of insertion in Canadian society. These paths and trajectories were analyzed from the theory of social networks and understood as adaptation strategies of immigrants. Different social groups and networks are formed in this process, including connecting individuals who intend to migrate, even in Brazil. Finally, gender differences were important in this process, they produced deferent types of networks and marked paths of women and men in the adaptation process in the city, having booked a chapter to this discussion.