Navegando por Assunto "Ipixuna - PA"

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Acesso aberto (Open Access)
A vida dirige o rio: cem anos de ocupação cabocla e extrativismo madeireiro no Alto Capim
(Universidade Federal do Pará, 2003-02-17) MEDINA, Gabriel; SHANLEY, Patrícia
In the Brazilian Amazon, the increasing rate of deforestation has prompted the international research community to look for solutions that reconcile conservation and development. Since the late 1980s, researchers throughout the world have explored the role that extraction of non-timber forest products (NTFPs) could have to the well-being of forest dwellers as well as to the environment. This thesis explores the role that NTFPs play in the lives of rural communities in a dynamically changing timber frontier region along the Capim River in the eastern Amazonian state of Pará. As the timber industry advances throughout the Amazon basin, communities located along logging frontiers are increasingly approached to sell the rights to their timber. Such communities consider several aspects to assess the value of forest products. Besides socio-economic and ecological values (real value), there is relative value, which strongly influence the way resources are used. This relative value is based on representations regarding the importance of forest products and on the context in which these representations are formed. To explore this theme, the thesis begins with a historical reconstruction of a caboclo community focusing on forest resource use and dynamics during the last hundred years. For the households within the study communities, timber always represented a natural heritage that could be spent over time. It was the principal product with market value and, during initial timber sales, extraction did not significantly reduce access to other forest products. Therefore, timber resources represented an inheritance with exchange value and little conflicting use. Four socioeconomic factors were identified which influenced communities to sell timber despite the losses in NTFPs that they began to experience over time: 1) paternalistic relationships among buyers and caboclos; 2) difficulties in common property resource management; 3) quick cash gained from timber sales guaranteed access to market products and; 4) expanding market involvement required increased cash to meet increasing needs. To understand the value which communities grant to forest products in their decision-making it is fundamental to identify the real alternatives that NTFPs represent to households and to compare this with other land use options.
Acesso aberto (Open Access)
Mapeamento de jazidas de bauxitas no Distrito Paragominas – Açailândia (PA-MA) pelo método da sísmica de refração
(Universidade Federal do Pará, 1986-12-29) BOLAÑOS ALVARADO, Ricardo Antonio; SCHIEL, Klaus Rainer; http://lattes.cnpq.br/1748862841375705
In the last 30 years, the mapping of bauxite deposits in Brazil has been carried out using drill holes. In this study, the refraction seismic method has been applied for the first time, with about 3000m of shallow profiles done on an experimental scale, at localities along the highway BR-10, as well as at Plato Esperança in the Jabuti region (PA), and near Açailândia county (MA), with the aim of delimitation of the bauxite layer. Although, the critical distance method has been used on some occasions to calculate thicknesses; this study has used the Generalized Reciprocal Method to process and interpret the data, to get the continuos delimitation of the layer being investigated. The GRM has an adventage compared to old traditional methods because, it delinates undulating refractors, infers undetected layers, and also is insensitive to dip angles up to 20 degrees. From the velocity analysis graph the velocity of the bauxite layer has been calculated, resulting in a mean of 840m/s. Using the time depth data it has been possible to map the bauxite, which has an irregular behavior and with a mean thickness of 5m. The geophysical research carried out at these areas turned out to be very important considering the fact that this method can be successfully applied to other regions having the same geological characteristics.
Acesso aberto (Open Access)
Parâmetros sangüíneos e urinários, no pré e pós parto, de búfalas criadas em sistema exclusivo de pastejo
(2003-06) OLIVEIRA, Carlos Magno Chaves; BARBOSA NETO, José Diomedes; BARBOSA, Imke Barbara Pfeifer; CARDOSO, Deugles Pinheiro
Eight lactating buffaloes of the Murrah breed were used from 60 days before up to 60 days after calving, in order to evaluate alterations in the concentration of blood glucose, total plasmatic protein, haematocrit and the presence of ketonic bodies in the urine. The 5 to 10- year old buffaloes were clinically healthy and had had at least two lactations. During the experimental period the animals were maintained on Brachiaria brizantha pasture and supplemented with a mineral mixture and water.The media concentrations of blood glucose and the media values of the haematocrit diminished significantly after calving (p<0,05). The concentrations of total plasmatic protein did not show significant variation during the pre and post-calving period. The ketonic bodies in the pre-calving period were only detected in the urine of one buffaloe, but after the 32nd day of lactation ketonic bodies were detected in all animals. There was a direct relationship between the color of the urine positive by the Rothera test and blood glucose concentrations. It can be concluded that at the beginning of lactation the buffaloes had an energetic deficit, characterized by a decline of blood glucose concentrations and the presence of ketonic bodies in the urine, and that lactation caused a progressive decline of the hematocrit, but that the concentration of total plasmatic protein did not vary during the pre and post-calving period.
Acesso aberto (Open Access)
Síntese e caracterização de analcina obtida a partir de rejeito caulim com aplicação em adsorção
(Universidade Federal do Pará, 2006-12-19) CORREA, Edinelson Saldanha; NEVES, Roberto de Freitas; http://lattes.cnpq.br/9559386620588673
In this work from kaolin processing industries from Ipixuna-PA were used in order to synthesi analcime derived zeolite as predominant crystalline phase though the hydrothermal process. The sample was converted into metakaolinite by calcinations at 700°C during 4 hours. From sample this metakaolinite a reacting mixture consisting of diatomite and sodium hydroxide was prepared. In order to determine of ideal conditions for analcime synthesis, a number of process variables were measured such as sodium availability, silicon ratio, nature of the silica source, pH of the reacting mixture, and auto clave residence time. Some important properties of the adsorbent where measured as well, such as thermal stability in the presence of acids hydrogen desorption kinetics, the trends of the adsorption isotherms as such as selectivity for copper, cadmium, zinc and nickel ions. Analcime synthesis from kaolin processing wastes was feasible. A displacement in the (h, k, l) planes was observed at 400 °C and was maintained up to 600°C, caused by the withdrawal of oxygen in positions 1/8 in analcime, shrinking the unit cell and in active channels and sites of zeolite, affecting its adsorption capacity.
Acesso aberto (Open Access)
Utilização de rejeito de caulim da Amazônia na síntese da zeólita A
(2007-09) MAIA, Ana Áurea Barreto; CORREA, Edinelson Saldanha; ANGÉLICA, Rômulo Simões; SOUZA, Célio Augusto Gomes de; NEVES, Roberto de Freitas
Zeolite A and Hydroxysodalite were synthesized after kaolin wastes from kaolin processing industries for paper coating, located in the Amazon region. The waste is mainly composed by kaolinite, which has the same SiO2/Al2O3 ratio requested for those two zeolites. Thereby, synthesis process may occur in two steps: 1) the kaolin was submitted to thermal treatment, through calcination process at 700 °C for 2 h, in order to obtain the metakaolinite phase. The metakaolinite obtained reacted with NaOH solution, in hydrothermal conditions, using autoclaves, at the following temperatures: 80, 110 and 150 °C for 24 h. The starting materials were identified and characterized by means of X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) analysis and synthesis products were characterized by means of XRD, SEM, Thermal Methods (DTA-DTG) and Fourier Transformed Infrared Spectroscopy (FTIR). A mixture of Zeolite A and Hydroxysodalite was obtained through this process at 150°C. In the temperature of 110 ºC there was only the Zeolite A formation. Nevertheless, in the lowest synthesis temperature (80°C) there was no crystalline material formation for the established conditions.