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Migrações de trabalhadores maranhenses para o corte da cana-de-açúcar no interior do Estado de São Paulo: o percurso da "precisão"
(Universidade Federal de São Carlos, 2011-12-17) Pontes, Sabrina Kelly; Alves, Francisco José da Costa; https://lattes.cnpq.br/9183120186518337
The end of the 90's was characterized in relation to the migration process bringing new elements. Among them, the impossibility of reproducing small family farms caused by the expulsion process. In this context, workers from Maranhão became the new actors, with workers from Minas Gerais and Bahia, and migrates to the state of São Paulo to work on cutting sugar cane. With this mind the objective of the thesis is to show that workers from distants regions of the country, specifically from Maranhão, are migrating to cut the cane in São Paulo, from the late 1990's? One hypothesis is that the Brazilian government has a participations in the migration of these workers by "promote" the process of expulsion through the adoption of agrobusiness as a development strategy of the country, besides the growth of the sugarcane industry after the 1990s mainly in the state of São Paulo. The used methodology is based on intensive literature review, using indicators of IBGE, Agricultural Census and official numbers showing that there is a crisis in the agricultural falmily on the state of Maranhão, and a study case of workers from Maranhão. It is conclude that, the migration of Maranhão, as pointed out earlier studies, it is not based on temporary wage as a means of keeping the family production unit, but in this case, migration is meant to keep the family unit. In these, cases the wage became definitive, because the process of expulsion and the politicies of Maranhão do not give condition to these small farmers, strengthening and making effective the migratory process.
Processamento e caracterização de cerâmicas transparentes do sistema ferroelétrico PMN-PT dopado com lantânio
(Universidade Federal de São Carlos, 2011-12-17) Badillo, Fernando Andrés Londoño; Garcia, Ducinei; https://lattes.cnpq.br/5236758856687873; https://lattes.cnpq.br/6266238277645440
In this work, one of the goals was the stabilization and/or optimization of the perovskita phase in the (Pb,La)(Mg1/3Nb2/3)O3+PbTiO3 (PLMN-PT) e Pb(Mg1/3Nb2/3)O3+PbTiO3+La2O3 (PMN-PT:La) powders in order to obtain ceramics with appropriate quality for optical applications. The stabilization of the system studied here was possible by the use of oxygen atmosphere in the powder calcinations process and densification process. Secundary phases, smaller to 5% and until 0% for the calcined powders and the densified pellets respectively were archived. After being given the best calcinations conditions, the pellets were conventionally and uniaxially hot pressing densified on oxygen atmosphere. For all the ceramics were performed structural, micro structural, and electrical characterizations. Comparisons between the systems studied (PLMN-PT and PMNPT: La) and between the densified processes used (conventionally and uniaxial hot pressing) were performed for all PT concentration. Relationship between vacancies and PT concentration were determined from measurements realized. Excellent properties were found for all the ceramics, as such, homogeneous microstructure, high density, free secondary phases and electrical properties as the reported in the literature. Light transmission (from visible to near infrared) was observed in ceramics obtained by uniaxil hot pressing. Electro-óptical characterization in function of frequency and temperature unprecedented were performed for all the transparent ceramics using the dynamic method Senarmont. Finally, electro-optics coefficient ideal for technological applications, this being, a clear sign of the excellent quality of the ceramics obtained in this work.