Distribuição de 137Cs em árvores frutíferas tropicais

• Ano de defesa: 2006
• Autor(a) principal: Mosquera, Bernardo Nepomuceno Pinto
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Programa de Pós-graduação em Física; Física
• Palavras-chave em Português: Contaminação radioativa; Radioatividade; Medição; CNPQ::CIENCIAS EXATAS E DA TERRA::FISICA
• Link de acesso: https://app.uff.br/riuff/handle/1/17345

The concentrations of 137Cs were measured from guava, mango and avocado trees, with the aim to verify how this radionuclide is transported and distributed along the tropical fruit trees. Bi-dimensionals diagrams of the radial distribution of 137Cs in the main trunk are also presented. Comparisons with a few longitudinal and radial distributions of 40K for these trees were performed. The results confirm the present knowledge on the transport and distribution of salts in fruit trees, where the specific 137Cs activity is higher in the growing parts of these trees: fruits, leaves, needles, twigs and the outer growth layers. On the other hand, it was observed that 40K radial distribution exhibits saturation for high values of 137Cs concentration. Thus, unlike for 137Cs, 40K absorption is regulated or limited by some mechanism. In addition, the bi-dimensional diagrams of the 137Cs radial distribution show more accurate results than the conventional one-dimensional diagrams, disclosing no symmetrical or homogeneous behaviors of the specific activity on either of the tree rings.