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Cooperativismo em assentamentos de reforma agrária: a sobrevivência de cooperativas do MST no contexto capitalista
(Universidade Federal de São Carlos, 2004-09-03) Vazzoler, Márcia Regina; Eid, Farid
This thesis has as objective to make a comparative study of cases between cooperatives of agrarian production - CPAs in agrarian reform settlements in the state of São Paulo and the state of the Rio Grande Do Sul, being analyzed the process of creation, development and limits taxes to the these cooperatives, verifying its internal organization of the production and the work and as this factor contributes for the success or economic and social failure of these cooperatives. We understand as failure those cooperatives that pass for difficulties of generation of income and consequence dissolution and as success those cooperatives whose factors economic and social they are not only seen as an end, but as a way for its growth. We leave of the principle of that a differentiation between the Traditional Cooperatives exists - that they function, over all, as capital society, or either, maximizes chances and reaches a similar economic rationality to the ones of the too much capitalist companies through technological, financial and organizacional mechanisms, increasing its production essentially in relation to the market, accumulating and centering capital without the main concern with social justice; and the selected ones for the development of this thesis of, the cooperatives of agrarian production - CPAs in agrarian reform settlements - that they function, above of everything, as a society of people. This type of organization of production and work possess character and socialist inspiration and if it characterizes for presenting a differentiated management, based in the historical principles of the cooperativismo. The organizations managed for itself same congregate majority or totality diligent agricultural in conditions of exercise of the collective ownership of the means of production, where the work associated it is organized by means of planning and determined collective norms and the results of the production are distributed on the basis of the participation of the work of each associate. As well as the traditional cooperatives, the CPAs of agrarian reform searchs the efficiency, however such efficiency is submitted to the logic of the social inclusion, of the preservation of the ranks of work and fight for the agrarian reform. We intend to answer which are the determinative factors of economic and social success of CPAs in agrarian reform settlements in São Paulo and the Rio Grande Do Sul and as the internal organization of the production and of the work of these cooperatives it contributes for this result.
Desenvolvimento e caracterização de composições polipropileno/cargas retardantes de chama
(Universidade Federal de São Carlos, 2004-09-03) Trombini, Rejane Cristina; Agnelli, José Augusto Marcondes; https://lattes.cnpq.br/7592090152400440
The main objective of this study was to develop and characterize polypropylene modified with flame retardant fillers. Two flame retardant fillers (Aluminum Hydroxide and Magnesium Hydroxide) were incorporated into four distinct types of polypropylene, two of which were homopolymers and two copolymers. The contents of the flame retardant fillers were 40 and 60%, in mass. The composites were prepared using two co-rotating double screw extruders, one a bench scale device and the other of considerably larger dimensions. The test specimens were then injection processed, after which the composites thermal, mechanical, thermomechanical and flammability performance were evaluated. An analysis was made of the thermogravimetric results to identify the possible occurrence of water loss during the composite s processing. The flame retardant fillers were found to improve the composite s flammability behavior, albeit with a concomitant decrease in their mechanical properties, most notably a drop in the material s impact strength. The best physical and mechanical properties and the lowest flammability were obtained with polymer-flame retardant filler composites whose polymeric matrix was composed of propylene-ethylene copolymer with the highest ethylene content. A study was also made of the properties of polypropylene and organic clay nanocomposites, from which a type of polypropylene most closely resembling the ones previously studied was chosen to serve as a standard against which to compare the properties obtained for the polypropylenes modified with traditional flame retardant fillers. Under the conditions utilized in this study, the nanocomposites displayed an adequate physical and mechanical behavior, but the evaluations revealed that no satisfactory increase in resistance to flammability was achieved.
Avalição química e da capacidade de biossorção da grama batatais (Paspalum notatum) visando aplicações analíticas
(Universidade Federal de São Carlos, 2004-09-03) Araújo, Geórgia Christina Labuto; Nogueira, Ana Rita de Araújo; https://lattes.cnpq.br/7034773971317045
This work suggests the chemical characterization of the genus Paspalum and was divided in 3 steps: 1) sample preparation of plants with diluted acids; 2) biosorption studies employing Paspalum notatum root material, and 3) investigation of root cellular wall constituents. Therefore, in the first step, solutions ranging from 2 to 14 mol L-1 HNO3 were used to assisted high-pressure microwave plant samples digestion. Quantitative amounts of analytes were obtained, including Fe and Al, by using 2 mL of 2 mol L-1 HNO3 solution plus 1 mL of H2O2 30 % v v-1. Residual carbon contents were ≤ 11 %. The 1H NMR spectra indicated lower variety of nitrocompounds for samples digested with diluted acids. For the second step, sorption studies in root material leached and no-leached with 0.14 mol L-1 HNO3 solution were performed. The sorption obtained for the former was higher than for the latter material. Sorption isotherms of Al3+, Fe3+, Cu2+ and Ni2+ in H3CCOONH4 and KNO3 environments with mono and multielemental solutions were plotted and adjusted to the more representative theoretical models for the experimental results. The KNO3 monoelemental studies presented higher sorption for Fe and Cu than for H3CCOONH4 environment, probably owing to the absence of bounding ions. Sorption has reduced for all analytes in KNO3 multielemental studies, probably owing to the competition by the sorption sites. In the other hand, H3CCOONH4 multielemental studies showed an increasing of two times for Fe and Al sorption, probably due to lateral interactions between the analytes and the biosorbent surfaces, which were verified with sorption isotherm profiles. In the last step, the 1H NMR spectra and the potentiometric titration indicated that the acid rinsing changed the material. In this case, interpretation of the results obtained with potentiometric titration suggests the amine and phenol groups as likely sorption sites. The determination of Al, Fe, Cu, Ni, aminoacids and sugar in fractions obtained from the sequential extraction of the cell wall compounds, combined to Pearson s correlation coefficient studies, evidenced different distributions of the analytes at the fractions and material. Thus, the functional groups related to each metal could be estimated.