Síntese e caracterização de pós Ba(x)Sr(1-x)Co0,8Fe0,2O3- através do método de coprecipitação via oxalato

Ceramic powders based on oxides of perovskite-type structure is of fundamental interest nowadays, since they have important ionic-electronic conductivity in the use of materials with technological applications such as gas sensors, oxygen permeation membranes, catalysts and electrolytes for solid oxide fuel cells (SOFC). The main objective of the project is to develop nanostructured ceramic compounds quaternary-based oxide Barium (Br), Strontium (Sr), Cobalt (Co) and Iron (Fe). In this project were synthesized compounds BaxSr(1-x)Co0, 8Fe0,2O3- (x = 0.2, 0.5 and 0.8) through the oxalate co-precipitation method. The synthesized powders were characterized by thermogravimetric analysis and differential thermal analysis (TGADTA), X-ray diffraction (XRD) with the Rietveld refinement using the software MAUD and scanning electron microscopy (SEM). The results showed that the synthesis technique used was suitable for production of nanostructured ceramic solid solutions. The powders obtained had a crystalline phase with perovskite-type structure. The TGA-DTA results showed that the homogeneous phase of interest was obtained temperature above 1034°C. It was also observed that the heating rate of the calcination process did not affect the elimination of impurities present in the ceramic powder. The variation in the addition of barium dopant promoted changes in the average crystallite size in the nanometer range, the composition being BSCF(5582) obtained the lowest value (179.0nm). The results obtained by oxalate co-precipitation method were compared with those synthesis methods in solid state and EDTA-citrate method

Fotografia e paisagens da modernidade : Currais Novos/RN de 1950 a 1980 / Gênison Costa de Medeiros

This dissertation promotes a dialogue between visual representation and the new cultural geography theory to critically examine the photography representation of an specific urban landscape. The interest here is to explore the ways in which the images of the city of Currais Novos - RN, captured by the photographer Raimundo Bezerra from 1950 to 1980, have taken a great part in shaping people s understanding and imagination of this city s modernizing process. What comes out of this work is the comprehension of that photography permites a geographical study of urban landscape as it can revel perceptions, imaginations, discourses e subjetivities which are based on especific urban cultural dreams and aspirations related to the case studied. So, the aim of this dissertation was to analyse how the discourse of modernity could be seen as part of and impregnated to the urban landscape of Currais Novos by Bezerra s photographs. Then, an intertextual, hermeneutic and phenomenalogical understanding of the geographic object and how it fits within the cultural context was fundamental

Aplicação de tecnologias eletroquímicas (oxidação via radicais hidroxila, oxidação mediada via cloro ativo e eletrocoagulação) para o tratamento de efluentes reais ou sintéticos

In this work the degradation of real and synthetic wastewater was studied using electrochemical processes such as oxidation via hydroxyl radicals, mediated oxidation via active chlorine and electrocoagulation. The real effluent used was collected in the decanter tank of the Federal University of Rio Grande do Norte (ETE-UFRN) of Effluent Treatment Plant and the other a textile effluent dye Ácido Blue 113 (AB 113) was synthesized in the laboratory. In the electrochemical process, the effects of anode material, current density, the presence and concentration of chloride as well as the active chlorine species on site generated were evaluated. Electrodes of different compositions, Ti/Pt, Ti/Ru0,3Ti0,7O2, BDD, Pb/PbO2 and Ti/TiO2-nanotubes/PbO2 were used as anodes. These electrodes were subjected to electroanalytical analysis with the goal of checking how happen the anodic and cathodic processes across the concentrations of NaCl and supporting electrolyte used. The potential of oxygen evolution reaction were also checked. The effect of active chlorine species formed under the process efficiency was evaluated by removing the organic matter in the effluent-ETE UFRN. The wastewater treatment ETE-UFRN using Ti/Pt, DDB and Ti/Ru0,3Ti0,7O2 electrodes was evaluated, obtaining good performances. The electrochemical degradation of effluent-UFRN was able to promote the reduction of the concentration of TOC and COD in all tested anodes. However, Ti/Ru0,3Ti0,7O2 showed a considerable degradation due to active chlorine species generated on site. The results obtained from the electrochemical process in the presence of chloride were more satisfactory than those obtained in the absence. The addition of 0.021 M NaCl resulted in a faster removal of organic matter. Secondly, was prepared and characterized the electrode Ti/TiO2-nanotubes/PbO2 according to what the literature reports, however their preparation was to disk (10 cm diameter) with surface area and higher than that described by the same authors, aiming at application to textile effluent AB 113 dye. SEM images were taken to observe the growth of TiO2 nanotubes and confirm the electrodeposition of PbO2. Atomic Force Microscope was also used to confirm the formation of these nanotubes. Furthermore, was tested and found a high electrochemical stability of the electrode Ti/TiO2-nanotubes/PbO2 for applications such as long-term indicating a good electrocatalytic material. The electrochemical oxidation of AB 113 using Ti/Pt, Pb/PbO2 and Ti/TiO2-nanotubes/PbO2 and Al/Al (electrocoagulation) was also studied. However, the best color removal and COD decay were obtained when Ti/TiO2-nanotubes/PbO2 was used as the anode, removing up to 98% of color and 92,5% of COD decay. Analysis of GC/MS were performed in order to identify possible intermediates formed in the degradation of AB 113.

Cartilha do silêncio: sob o signo da modernidade e da memória

This research starts from the presupposition that Cartilha do Silêncio(1997), a novel by the Brazilian writer Francisco Dantas, has a double articulated shift. One of the moves is towards the modern experience, with the idea that modernity is filled with contraries, as remarked by Nietzsche; the other is linked to the livelihoods ashore on traditional experiences, which encompasses the notion of memory as individual and collective ownership. The aim here is to analyze such perspective, social and critical issues within the characters' life stories that regards the calling of past as clear example that tradition is not gone, though modern life presents its own signs. Such dynamics gives to the plot a paradoxal feature. This work is mainly grounded on Marshall Berman' s thoughts in All That Is Solid Melts Into Air: The Experience of Modernity (1982) as well as on Antoine Compagnon'sFive Paradoxes of Modernity (1994). Assuming that Francisco Dantas' Novel is set as a split narrative, outcome of social memory originated on individual experiences aside social process and patriarchal family, this research brings into play the concept of memory by Jacques Le Goff in History and Memory (1992) along EcléaBosi's study in Memória e Sociedade: lembranças de velhos (1979). Keen to check how Cartilha do silêncio adjoins modern livelihoods with aesthetics order, the method articulates text and context, literary and social life, according to Antonio Candido'sLiteratura e Sociedade (1965). Thus, after reading the novel, it is possible to notice how the identity of the characters are built throughout the plot and it is also kept against settling on its social context during the transition from patriarchal tradition to modernity, creating a taut mood between both registries.

As Bibliotecas Universitárias de Portugal e Nordeste do Brasil: estudo sobre o impacto e mediação das tecnologias digitais

Analisa as práticas de mediação desenvolvidas nas bibliotecas universitárias pelos bibliotecários diante das tecnologias digitais. Para tanto estabelece como objetivo geral analisar de forma comparativa, o impacto e mediação das tecnologias digitais no funcionamento de bibliotecas Universitárias de Portugal e da região Nordeste do Brasil. Integraram esta pesquisa 10 universidades federais brasileiras e 12 universidades públicas portuguesas, com um total geral de 115 bibliotecários, que são os sujeitos participantes. É uma pesquisa qualitativa que adota o método quadripolar – recomendado para os trabalhos desenvolvidos no âmbito das Ciências Sociais Aplicadas, e em especial na área de Ciência da Informação. Através da interação entre os polos: epistemológico, teórico, técnico e morfológico, que fundamentam este método, houve o fortalecimento e a fluidez das questões estudadas. Os resultados dos questionários aplicados aos bibliotecários, bem como da análise dos sítios das bibliotecas pesquisadas, foram interpretados através de um alicerce teórico baseado em três pontos principais: as questões paradigmáticas que envolvem a área de Ciência da Informação, a análise da mediação pós-custodial informacional e científica e as Tecnologias de Informação e Comunicação presentes nas bibliotecas. Como principais resultados vemos que o impacto das tecnologias digitais nas bibliotecas universitárias é considerado pelos bibliotecários brasileiros e portugueses como positivo, com ênfase em dois pontos: a inovação dos suportes de informação e a autossuficiência dos utilizadores. A maior diferença se percebe em relação ao aspecto social, através de uma maior preocupação entre os bibliotecários brasileiros com as barreiras informacionais causadas por questões econômica, social e educacional e sentido com menos intensidade pelos bibliotecários portugueses, que ascendem as tecnologias digitais com mais facilidade. De forma conclusiva, a análise do impacto e a mediação das tecnologias digitais nas bibliotecas pesquisadas, apontam para uma evolução nas práticas mediadoras das bibliotecas universitárias de Portugal e do Nordeste do Brasil e uma convergência laboral entre os bibliotecários portugueses e brasileiros.

Fatores inibidores à adoção de tecnologias de informação em micro e pequenas empresas fornecedoras da vale no estado do Pará

Universidade Estadual do Rio Grande do Norte

Cerâmica de Santo Antônio do Potengi: entre tradição e modernidade

In the Rio Grande do Norte, the craftsmanship is generating of economy, it involves a significant number of people and is diversified in its raw materials and particular type. As reference of the craft local, the ceramics supplied the primary necessities in the utilitarian domestic servants, acquired piety in the religious figures, were toy in infantile amusements and, finally, gained status of pure ornament. By its historical representation, the district of Santo Antônio do Potengi is considered the most important center of manufacture of craftpottery in the State. The work of the potters continues in that locality anchored between the familiar inheritance and the participation each more influential time of the public politics destined to the sector situation verified for visible alterations in the shape of the pottery from the decade of 1990 with the implantation of a cooperative destined to the collective production. We observe in this passage, that such actions in the measure where they objectify to structuralize conditions ideal to support the artisan making, do not benefit in significant way the social development them craftsmen. It is important not to lose of sight that exists some involved dimensions in this process and that these surpass the common interest for the object and the consequent economic connotation of its commercialization. They are knowledge that imply in the access to raw materials, in the peculiar of the formal aspects and productive methods, in the contextual relations organized to defend the survival of the activity

Um espaço pioneiro de modernidade educacional: Grupo Escolar Augusto Severo -Natal/RN -1908-13

Cette recherche a pour but d analyser l Ecole Augusto Severo, située dans la ville de Natal dont la construction date de 1907,étant le premier établissement d enseignement primaire à l état du Rio Grande do Norte, pendant le processus de restructuration de l enseignement républicain. On cherche à comprendre la représentation de ce milieu scolaire, comme équipement urbain, dans le processus de modernisation de la ville et comme modèle éducationnel pour l état entre 1908 et 1913. En se servant des études historiographes sur le processus de modernisation de quelques villes brésiliennes et des innovations de l enseignement public primaire au pays, à la fin du dix-neuvième siècle et pendant la première décennie du vingtième siècle, comme source pour mieux saisir le contexte général et spécifique. On reconstitue les aspects économiques, sociaux et politiques déterminants des interventions publiques réalisées dans cette ville par les gouvernements républicains ayant comme obectif la construction d une ville embellie,hygiénique et civilisée. Située au quartier Ribeira, principal scénario de la modernité de Natal, l Ecole Augusto Severo est mise em relief comme symbole de civilité du paysage urbain de l époque pour le citoyen du Rio Grande do Norte. Elle disposait de services d énergie et d un tram électrique. Il y avait devant, un grand lac arborisé et une station ferroviaire. A côté, il y avait le théâtre Carlos Gomes (actuellement Alberto Maranhão). Par suíte de son imposante architecture, raffiné style éclectique,on reflète l idéal républicain des elites locales, avec une conception d espace symbolique et éducative de surveillance et contrôle, caractéristiques de l école graduée républicaine