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In this work, the effect of Fenton's reagent on the degradation of residual Kraft black liquor was investigated. The effect of Fenton's reagent on the black liquor degradation was dependent on the concentration of H2O2. At low concentrations (5 and 15 mM) of H2O2, Fenton's reagent caused the degradation of phenolic groups (6.8 and 44.8%, respectively), the reduction of reaction medium pH (18.2%), and the polymerization of black liquor lignin. At a high concentration (60 mM) of H2O2, Fenton's reagent induced an extensive degradation of lignin (95-100%) and discoloration of the black liquor. In the presence of traces of iron, the addition of H2O2 alone induced mainly lignin fragmentation. In conclusion, Fenton's reagent and H2O2 alone can degrade residual Kraft black liquor under acidic conditions at room temperature.

Experiments with soft phosphate and fertilizer grade concentrated superphosphate and diammonium phosphate were to measure effects on voluntary intake of their fluoride in relation to that from calcium fluoride and sodium fluoride given once daily by capsule. Mature wethers were offered 1200 or 1400 g daily of mixed grain-roughage diet, and responses to fluoride were measured by inappetence, consumption of less than 10% of offered diet. When 40 ppm fluoride as sodium fluoride was given for 2 days, inappetence resulted, whereas 2,400 ppm fluoride as calcium fluoride did not decrease feed intake. Time required for recovery of appetite increased with more fluoride. When soft phosphate, concentrated superphosphate, and diammonium phosphate were tested at 100, 200, and 400 ppm fluoride, inappetence occurred always but severity of reduction of intake was related to parts per million fluoride. Solubility of fluoride in soft phosphate, concentrated superphosphate, and diammonium phosphate is more similar to sodium fluoride than to calcium fluoride, and their use should be in keeping with fluoride tolerances established for ruminants fed sodium fluoride.

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O artigo apresenta dados etnográficos e contextuais sobre o processo de caracterização e identificação de terras tradicionalmente ocupadas por comunidades vazanteiras, pescadoras e quilombolas do Médio São Francisco, estado de Minas Gerais, Brasil. Tem como foco analisar os desafios do fazer antropológico na atual conjuntura política e econômica brasileira, marcada pela emergência de um novo tipo de antiambientalismo de caráter autoritário e racializado (ACSELRAD, 2018), baseado em uma retórica explicitamente estigmatizadora em relação aos povos e comunidades tradicionais, movimentos sociais, pesquisadores e órgãos públicos. Tal retórica, tem sido utilizada como estratégia de convencimento social e como forma de legitimar práticas de desregulamentação ambiental e fundiária. Para tanto, foi realizada pesquisa bibliográfica e documental, trabalho de campo etnográfico e análise situacional para leitura dos processos em andamento durante trabalho de pesquisa. Os dados revelam que, o que está em jogo é a apropriação privada pelo segmento ruralista das águas e das áreas inundáveis nas margens do rio São Francisco, que compõem parte dos territórios de diversas comunidades tradicionais,  sendo definidas pela legislação como terras da União e áreas de preservação permanente.