Síntese e caracterização de poliacrilamidas modificadas para utilização na indústria do petróleo

Modified polyacrylamides with ≅ 0.2 mol % of N,N-dihexylacrylamide and hydrolysis degree from 0 to 25 % were synthesized by micellar copolymerization. The hydrophobic monomer was obtained by the reaction between acryloyl chloride and N,Ndihexylamine and characterized by infrared (IR) and proton nuclear magnetic resonance (1H NMR) spectroscopy. The polymer molecular structures were determined through 1H and 13C NMR spectroscopy and the polymers were studied in dilute and semi-dilute regimes by viscometry, rheometry, static light scattering and photon correlation spectroscopy, at the temperature range from 25 to 55 ºC. The data obtained by viscometry showed that the intrinsic viscosity from the hydrolyzed polymers is larger than the precursor polymers at the same ionic strength. The comparison between the charged polymers showed that the polymer with higher hydrolysis degree has a more compact structure in formation water (AFS). The increase of temperature led to an enhanced reduced viscosity to the polymers in Milli-Q water (AMQ), although, in brine, only the unhydrolyzed polymer had an increase in the reduced viscosity with the temperature, and the hydrolyzed derivatives had a decrease in the reduced viscosity. The static light scattering (SLS) analyses in salt solutions evidenced a decrease of weight-average molecular weight (⎯Mw) with the increase of the hydrolysis degree, due to the reduction of the thermodynamic interactions between polymer and solvent, which was evidenced by the decrease of the second virial coefficient (A2). The polymers showed more than one relaxation mode in solution, when analyzed by photon correlation spectroscopy, and these modes were attributed to isolated coils and aggregates of several sizes. The aggregation behavior depended strongly on the ionic strength, and also on the temperature, although in a lower extension. The polymers showed large aggregates in all studied conditions, however, their solutions did not displayed a good increase in water viscosity to be used in enhanced oil recovery (EOR) processes

O estágio não-obrigatório na formação profissional dos(as) assistentes sociais: trabalho precarizado ou processo didático-pedagógico?

Coexisten, en el universo académico, prácticas curriculares obligatorias y no obligatorias que pueden ser remuneradas o no. Delante de la constatación de lagunas en la concepción, gestión y operacionalización de las prácticas no obligatorias remuneradas, escogimos este tema como objeto de nuestra investigación, tratando de analizarlo en el contexto de los cambios sociohistóricos contemporaneos y su influencia en la cualidad de la formación profesional del estudiante de la carrera de Servicio Social. Este estudio tiene como ¨locu¨ de investigación la Facultad de Servicio Social del Estado de Rio Grande del Norte (FASSO/UERN). Este estudio se caracteriza por la adopción de una perspectiva de análisis cualitativa, con la expectativa de develarlo mucho más allá de lo que se muestra en su aparecncia. Para esto, realizamos revisión de literatura, análisis de documentos, observación asistemática y entrevistas con estudiantes y profesionales de las entidades que ofrecen prácticas a los estudiantes. Además se incluyó, en los procedimientos metodológicos, la aplicación de encuestas y conversaciones informales. Constatamos la existencia de lagunas en el desarrolllo de las prácticas no obligatorias remuneradas, ocasionadas por la ausencia de supervisión y por la inclusión de pasantes en sectores y/o actividades desvinculadas de su futura profesión. La investigación nos permitió desvelar situaciones en las que la oferta de plazas ocurre en detrimento de la contratación de empleados, lo que configura un distanciamento de este componente curricular del área de formación profesional, desvirtuando su carácter educacional. Cientes de la coexistencia contradictoria entre situaciones ventajosas y problemáticas en las prácticas no obligatorias remuneradas para el proceso de formación profesional de los asistentes sociales, concluimos que esta modalidad de práctica cuando vinculada a la intervención de la facultad y bajo la supervisión de asistentes sociales, independiente de sus implicaciones en los intereses del mercado, potencializa el desarrollo de competencias y habilidades intrínsecas al proceso de formación profesional; pero si distanciada del área de formación y/o sin el debido acompañamiento didáctico-pedagógico establece poca o ninguna relación con la formación de los asistentes sociales. Pero, incluso distanciadas del ejercicio y de la formación académica en el área de servicio social y/o (llenas de aspectos frágiles) llenas de fallas en el proceso de enseñanza y aprendisaje, estas experiencias ejercen profunda influencia en la formación de los asistentes sociales, pudiendo fragilizar el compromiso con el proyecto ético-político, diseminar el aspecto subalterno de la profesión y hacer confuso y conflictivo el proceso de construcción de la identidad profesional. En este sentido, las inversiones de capital para reducir los gastos con mano de obra, las dificultades vividas por las universidades públicas brasileñas para garantizar la cualidad de la enseñanza delante de la insuficiencia de recursos humanos y materiales y la desvalorización de los componentes no obligatorios del proceso de formación profesional de los asistentes sociales, son factores que obstaculizan el reconocimiento y la materialización del potencial didáctico-pedagógico de las prácticas

Coeficientes de incidência do dengue e sua relação com os diferenciais intra-urbanos segundo condições de vida no município do Natal, Rio Grande do Norte

This study sprang from the hypothesis that spatial variations in the morbidity rate for dengue fever within the municipality of Natal are related to intra-city socioeconomic and environmental variations. The objective of the project was to classify the different suburbs of Natal according to their living conditions and establish if there was any correlation between this classification and the incidence rate for dengue fever, with the aim of enabling public health planners to better control this disease. Data on population density, access to safe drinking water, rubbish collection, sewage disposal facilities, income level, education and the incidence of dengue fever during the years 2001 and 2003 was drawn from the Brazilian Demographic Census 2000 and from the Reportable Disease Notification System -SINAN. The study is presented here in the form of two papers, corresponding to the types of analysis performed: a classification of the urban districts into quartiles according to the living conditions which exist there, in the first article; and the incidence of dengue fever in each of these quartiles, in the second. By applying factorial analysis to the chosen socioeconomic and environmental indicators for the year 2000, a compound index of living condition (ICV) was obtained. On the basis of this index, it was possible to classify the urban districts into quartiles. On undertaking this grouping (paper 1), a heterogeneous distribution of living conditions was found across the city. As to the incidence rate for dengue fever (paper 2), it was discovered that the quartile identified as having the best living conditions presented incidence rates of 15.62 and 15.24 per 1000 inhabitants respectively in the years 2001 and 2003; whereas the quartile representing worst living conditions showed incidence rates of 25.10 and 10.32 for the comparable periods. The results suggest that dengue fever occurs in all social classes, and that its incidence is not related in any evident way to the chosen formula for living conditions

Estudo do fluxo de neutrino solar com o código evolutivo de Toulouse - Geneva

The study of solar neutrinos is very important to a better comprehension of the set of nuclear reactions that occurs inside the Sun and in solar type stars. The ux of neutrinos provides a better comprehension of the stellar structure as a whole. In this dissertation we study the ux of neutrinos in a solar model, addressing the neutrino oscillation, analyzing with the intention of determining and verify the distribution from a statistical point of view, since this ux depends on the particles intrinsic velocity distributions in stellar plasma. The main tool for this analysis was the Toulouse-Geneva Stellar Evolution Code, or TGEC, which allow us to obtain the neutrino ux values per reaction and per layer inside the Sun, allowing us to compare the observational results for the neutrino ux detected on experiments based on Cl37 (Homestake), Ga71 (SAGE, Gallex/GNO) and water (SNO). Our results show the nal distribution for neutrino ux as a function of the depth using the coordinates of mass and radius. The dissertation also shows that the equations for this ux are present in TGEC.

Diagênese e proveniência dos arenitos da tectonossequência Rifte na bacias do Rio do Peixe Araripe, NE do Brasil

This thesis presents diagenetic and provenance studies of sandstones belonging to the Rift Tectonosequence of the Rio do Peixe and Araripe basins. These basins are located in the interior of Northeast Brazil aligned along the Trend-Cariri Potiguar. Their origin is related to the Early Cretaceous rifting event. In terms of lithostratigraphy, the studied section corresponds to the Antenor Navarro, Sousa and Rio Piranhas formations of the Rio do Peixe Basin, and the Missão Velha and Abaiara formations of the Araripe Basin, outcropping in the central-west Cariri Valley. A facies analysis was performed and identified nine distinct sedimentary facies for the Rio de Peixe Basin and ten sedimentary facies for the Araripe Basin, individualized according to the different rock types and their sedimentary structures. These facies associations to led paleoenvironments interpretations and their vertical succession allowed understanding the evolution of the depositional setting during the cronostratigraphic interval studied in these basins. Based on petrographic and diagenetic studies it was possible to characterize the texture and mineralogy of these sandstones, identifying their diagenetic stage and the grain framework provenance. The petrographic study allowed to classify the lithotypes studied in both basins as quartzarenites. Such quartzarenites, in general, are rich in quartz, feldspar and lithic fragment grains, and at accessory levels tourmaline, sphene, zircon, epidote and other mineralogy. The diagenetic history of the studied rocks proved to be very complex, being characterized by a variety mineral of phases that succeeded each other during the eo, meso and telodiagenetic stages. According to the studied formation and the textural and compositional aspects of the rocks, some processes were more or less active, while others were even absent. The eodiagenetic stage is marked by mechanical infiltration of clays and early mechanical compactional processes. The mesodiagenetic phase is characterized by continuity of the mechanical compaction and the beggining of chemical compaction, with quartz and feldspar overgrowths, precipitation of kaolinite, alteration of framework grains to chlorite and illite, and finally, precipitation of opaque minerals. The telodiagenetic stage is represented by the oxidation of some grains, matrix and cements. For the provenance analysis of the studied sandstones were used ternary diagrams whose vertices correspond to the percentage of quartz, feldspar and lithic fragments. This study allowed identifies the source area of these rocks as continental blocks. It was also possible, based on the chemical stability and mineralogical maturity of the rocks, recognize that the Antenor Navarro Formation of the Rio do Peixe Basin, and the upper section of the Missão Velha Formation of Araripe Basin have less maturity and stability when compared with the other studied formations

Mercado imobiliário informal e dinâmica urbana: o caso do bairro de Mãe Luiza Natal/RN

This paper aims at analyzing the dynamics of informal housing in Mãe Luiza, in the context of real estate valuation of the city of Natal/RN, which, like any other urban center, has problems related to access to urban land, which increasingly more is appreciated due to their scarcity and, consequently, has led to the segregation of urban spaces. Recently, the informal housing market has received special attention by scholars who wish to discuss the production of space and ways of access to urban land and housing, especially for those disadvantaged by the housing policies of the government where these exist. When talking about the housing market, we are automatically referring to concepts or categories intrinsic to the existing mode of production in our society - the capitalism. Thus, the categories: income, value (use and exchange), commodity, capital, profits and capital gains, along with other important concepts as well as land use (urban) and real estate agents are of great relevance to discussion we intend to do within the context of production space

Crescimento e mortalidade de Brycon opalinus (Characiformes, Characidae) no Parque Estadual da Serra do Mar, Mata Atlântica, Estado de São Paulo

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Efeitos da radiação laser de dióxido de carbono em tecido ósseo: estudo macroscópico em ratos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Structural control over well productivity in the Jundiaí River Catchment, Southeastern Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Por que as cooperativas agropecuárias e agroindustriais brasileiras estão falindo?

Este ar tigo evidencia as contradições do Modelo Cooperativista brasileiro em relação ao Modelo Original. Trata- se de incoerências intrínsecas na formação do movimento cooperativo, nos princípios para a sua condução ideológica, bem como na regimentação e operacionalização estatutária. A partir desses desacertos, o artigo mostra as restrições para o exercício da autogestão. Também sugere mudanças nas leis cooperativistas vigentes, propícias ao exercício da participação dos associados no processo decisório.

Reabilitação neuropsicológica pediátrica

A neuropsicologia investiga a expressão comportamental das disfunções cerebrais, isto é, a interação entre estruturas cerebrais preservadas e prejudicadas e as funções cognitivas, tais como linguagem, memória, atenção e outras. A neuropsicologia pediátrica possui especificidades: maturação, estratégias cognitivas, ensino formal e cultura, e características intrínsecas à reorganização cerebral. O objetivo da reabilitação neuropsicológica é estabelecer estratégias para adaptação de funções cognitivas afetadas em relação às demandas do ambiente da criança. A reabilitação cognitiva pediátrica auxilia crianças com deficiência mental, epilepsia, traumatismo craniencefálico, síndromes autísticas, tumores cerebrais, paralisia cerebral, etc. Programas de reabilitação neuropsicológica podem ser voltados para dificuldades acadêmicas ou para funções cognitivas. A investigação da efetividade de programas de reabilitação depende de diversos fatores. O neuropsicólogo deve contribuir para o desenvolvimento de novas estratégias de reabilitação cognitiva, ser qualificado para o uso das mesmas e partilhar, com a equipe interdisciplinar, as técnicas e experiências efetivas.

Aglomeraciones pesqueras en América Latina: ventajas asociadas al enfoque de cluster

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Fomentar la coordinación de las políticas económicas en América Latina: el método REDIMA para salir del dilema del prisionero

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Política fiscal en países especializados en productos no renovables en América Latina

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Diseño de un sistema de medición de desempeño para evaluar la gestión municipal: una propuesta metodológica

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