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Estudo da formação e remoção de tortas de filtração de gases em filtros de tecidos de polipropileno e de algodão
(Universidade Federal de São Carlos, 2004-06-15) Rodrigues, Antonio Carlos Marques; Aguiar, Mônica Lopes; https://lattes.cnpq.br/0431688649128529
The purpose of this work is to evaluate and to compare, in the processes of cake formation and remotion in the gases filtration with Bag Filters, the behavior of a filter made of natural fibers fabric with other made of synthetic fibers. The fabrics compared were a woven cotton with granite texture of 0.735 kg/m² and a non woven polypropylene of 0.600 kg/m². The experimental apparatus consisted of a circular filter with 0.023 m² in area, a powder feeder with controlled powder flow rate and humidity, linked with a microcomputer and a system to collect de data. The particle material was a phosphatic concentrated of density 2.79 x 10³ kg/m³ with mean particle diameter of 4.55 x 10-6 m. In the realization of this work, they were accomplished filtering procedures of the particle material in samples of the mentioned fabrics and cake remotion procedures with reverse air flow procedure, in order to determine the cake removing tension by the method proposed by Seville et al. (1989), also being evaluated other filtration and remotion aspects and data. In order to compare e evaluated the behavior of the fabrics in job conditions, they were also accomplished successive filtration and cleaning cycles in both fabrics until they become particle material saturated. During filtration four gas velocities were employed (4.5; 6.0; 7.5 and 9.0 cm/s), the flow rate was adjusted to 2.0 x 10-5 kg/s (11% of the feeder total velocity) and three maximum pressure drops across the filter were employed (300 mmH2O, 400 mmH2O and 500 mmH2O). In the cleaning steps six cleaning gas velocities were employed (1.6 cm/s; 3.0 cm/s; 9.0 cm/s; 12.0 cm/s; 15.0 cm/s and 18.0 cm/s). In the successive filtration and cleaning cycles they were employed gas filtration velocity of 6.0 cm/s, filtration final pressure drop of 400 mmH2O and gas cleaning velocity of 18.0 cm/s. The polypropylene fabric has taken more cycles to be saturated with the powder in the filtration and cleaning cycles and presented a greater cleaning degree in the cleaning processes, 77% in average, than the cotton that presented 39% of cake removal in average. The polypropylene fabric porosity was found to be greather than the cotton fabric ones. The cake-fabric adhesion force per unit of area has increased with the increase of the filtration gas velocity for both clothes, being remarkable that the polypropylene fabric has presented greather values than the cotton fabric, especially for the cakes formed with filtration gas velocities of 6.0 and 7.5 cm/s. It was also observed that the cake plaques, removed in the cleaning procedures, have increased in size with the increase of the cake removed portion and with the cake mass per unit of area for both studied fabrics.
Legislação e educação: o ideário reformista do ensino primário em Sergipe na Primeira República - 1889-1930.
(Universidade Federal de São Carlos, 2004-06-15) Oliveira, Dilma Maria Andrade de; Bittar, Marisa; https://lattes.cnpq.br/2452755458267316
The present work intends to discuss the genesis of the Republican teaching in the State of Sergipe (northeast of Brazil), from 1889 to 1930, also called First Republic or Old Republic. The Republic, initiated in 1889, comes together with the belief in the necessity of a remodeling of the economical, political and social order, and in the conviction that education would be the strongest tool for the consolidation of the republican regimen and for the construction of a modern country, capable of offering the people the conditions to be inserted in a representative democratic regimen. In the educational field, it can be pointed out the reforms directed to the public instruction by the State and the Union. The Republic would educate, instruct and form the refined men and free citizens. From the instruction development, men with a new mentality would be born to overcome the intellectual and cultural delay of the country. What was proposed and which possible historical direction of the school education in the First Republic in relation to the structure, to the organization and to the assistance of the primary teaching in the State of Sergipe? We have taken as presumption that the educational laws reveal, in a judging/ institutional and political level, the educational proposals of the ruling segments of the society, while part of a historical social process, in which for their legitimacy through the available tools, the maintenance and consolidation of a certain form of power. For the survey of the issues we have used, firstly , the usual techniques of the work with primary and secondary document resources highlighting the laws, decrees, rules and messages of the government and newspapers from 1889 to 1930, in the state of Sergipe. In the set of actions and procedures, the pedagogical as well as the we political ones, we have evidenced the absence of direction, of a clear design in leading a broad project, that had favored the entrance of the majority of the population to the school education. On the hand, the amount of legal acts directed to the public instruction in order to reform it, is showing that the education was thought and reaffirmed insistently with the purpose of incorporating a republican society project that also has not maintained itself.
Determinação do potencial de seqüestro de carbono na recuperação de matas ciliares na região de São Carlos - SP
(Universidade Federal de São Carlos, 2004-06-15) Martins, Osvaldo Stella; Tundisi, José Galizia; https://lattes.cnpq.br/5730659239785432
The loss of natural forest coverage reached 86% from total forested areas in São Paulo State until the year 2003. This scenario gets more critical when gallery forests are taken into acount. This particular kind of forests offers ecological services even more important than normal forests. Even inside law protected areas as well as permanently protected areas (CPA) riverside forests have been progressively devastated. Clearing of riverside forests, besides other problems, causes water resources depletion as the rivers lose this kind of natural protection. A critical factor on riverside forest recovery is related to the high costs on planting and maintaining reforested areas. This work presents an analysis developed to evaluate the potential carbon sequestration on recovering gallery forests, aiming to obtain CERs (Certified Emission Reductions) from a CDM (Clean Development Mechanism) project, as foreseen in the Kyoto Protocol. The proposal is divided in four main steps. In the first step the target area is defined and the total CPA area is marked. Then, which part of the CPA area is still forested and which part is not are determined. During the third step the local gallery forest main characteristics are analised. In the fourth step the information regarding development duration, population size of each tree species and individual diameter at breast heigth (DBH) are used to calculate the amount of carbon accumulated in the reforested area. Finally the proposal is applied for the micro-basin of Jacaré-Guaçu River, in São Carlos (21°30´S, 47°30´W) region, São Paulo State, Brazil. The results show an accumulation of 95tC/ha considering above ground and roots biomass and a cost for sequestred carbon of US$ 7/tCO2eq. Considering the actual CER´s market value, US$ 5/tCO2eq the carbon credits are not enough to meet the costs of reflorestation but represents a valuable contribution.