Estudos de óxidos magnéticos em solos de Roraima

• Ano de defesa: 2013
• Autor(a) principal: Silva, Gilmar Alves
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Roraima; Brasil; CCT - Centro de Ciência e Tecnologia; PPGFIS - Programa de Pós-Graduação em Física; UFRR
• Palavras-chave em Português: Difratometria de raios; Análise termomagnética; Espectroscopia Mössbauer; Óxidos de ferro; Solos de Roraima; Mössbauer spectroscopy; X-ray diffraction; Thermomagnetic analyzes; Iron oxide; Soils of Roraima; CNPQ::CIENCIAS EXATAS E DA TERRA::FISICA
• Link de acesso: http://repositorio.ufrr.br:8080/jspui/handle/prefix/11

The research was mainly devoted to the characterization of iron oxides (magnetic phases) present in soils in four municipalities of Roraima, included five different points located in the East Central State. The techniques used were X-ray diffraction (RDX), thermomagnetic analyzes (ATM) and Mössbauer spectroscopy (MS). XRD results showed the occurrence of phases of iron oxides, silicon, aluminum and other stages fewer. The ATM proves that the magnetic phases are magnetite, maghemite and hematite. The MS confirms the results of XRD and ATM, with phases having hyperfine parameters typical of oxides of iron (Fe). From the results of MS quantify the iron oxides present as 35% magnetite (Fe3O4), maghemite 27% (γFe2O3); 16% hematite (αFe2O3); 12% goethite (2FOOH) and 10% ilmenite (FeTiO3 ), the above result is magnetite iron oxide majority.