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Bagaço de cana-de-açúcar e raízes de alface empregados como biossorventes de íons metálicos em meio aquoso
(Universidade Federal de São Carlos, 2017-06-05) Milani, Priscila Aparecida; Carrilho, Elma Neide Vasconcelos Martins; https://lattes.cnpq.br/5147872007117167; https://lattes.cnpq.br/2420667904233275
Sugarcane bagasse and hydroponic lettuce roots were used as biosorbents for Cu(II), Fe(II), Zn(II) and Mn(II) removal from mono and multielement solutions, as well as in lake water, at pH 5.5, in batch processes. These biomasses were studied in natura (lettuce roots, NLR, and sugarcane bagasse, NSB) and chemically modified with HNO3 (lettuce roots, MLR, and sugarcane bagasse, MSB). The results showed that higher adsorption efficiency was achieved with the modified biomass, with the exception of lettuce roots, which also presented similar efficiency when used in natura. The removal experimental quantities (qexp) in monoelement solution, calculated using the Langmuir isothermal model for Cu(II), Fe(II), Zn(II) and Mn(II) were respectively, 1.22, 1.08, 1.40 and 1.23 mg g-1 in NLR, and 1.69, 1.68, 1.09 and 1.48 mg g-1 in MLR and 0.58, 0.036, 0.40 e 0.24 mg g-1 in NSB, and 1.30, 1.41, 1.55 and 1.02 mg g-1 in MSB. The removal experimental quantities (qexp) in multielement solution containing Cu(II), Fe(II), Zn(II), and Mn(II) in multielement solution were 1.28, 1.41, 1.29 and 1.05 mg g-1 in NLR, and 1.30, 1.09, 1.72 e 1.64 mg g-1 in MLR, and 0.47, 0.58, 0.09 and 0.02 mg g-1 in NSB, and 1.30, 1.09, 1.06 and 1.62 mg g-1 in MSB, respectively. We used the isothermal models of Langmuir and Freundlich, however for multielement solutions the adsorption did not conform to the Freundlich isotherm. In the kinetic studies with modified biomasses, sorption was achieved in the first 5 minutes and reached equilibrium in 30 min. The O-H, C-O-C, C-C, C-H, and C=O groups were found in the characterization of the biomass sorption sites by Fourier transform infrared spectrometry (FTIR). In the determination of the biomass surface charges using blue methylene and red amaranth dyes, there was a predominance of negative charges. Modified biomasses were used in the adsorption of Cu(II), Fe(II), Zn(II), and Mn(II) in lake water, in which retention of 24.31, 14.50, 8.21, and 8.03 mg g-1 by MLR, and 13.15, 10.50, 5.14 and 6,10 mg g-1 by MSB was found, respectively.
Caracterização da pecuária leiteira do município de Muriaé, MG: uma reflexão sobre perspectivas futuras
(Universidade Federal de São Carlos, 2017-06-05) Vasconcelos, João Marcos Carvalho; Schlindwein, Marcelo Nivert; https://lattes.cnpq.br/9690898537150950; https://lattes.cnpq.br/5880919055676173
The objective of this work is to evaluate the current situation of the activity, production base and technological level used by the producers affiliated to the Muriaé Livestock Program, in the following points: characteristics of the properties, productivity, animal nutrition, techniques developed and animal health. The work includes a micro-region of the municipality of Muriaé / MG, 129 producers affiliated to the Muriaé Livestock Program were interviewed, with a semi-structured questionnaire application. The questionnaire included: characteristics of the properties, productive activities, animal nutrition, techniques developed and animal health. Small farms, consumer goods, leased and lending station, main income dairy production, household base labor in most of the properties, non-agricultural activities in the part of the dynamics of the properties, Variation of five species of grasses, breeds European cattle, and the cross between them. The productive process in the properties and directed to the milk production, as well as a herd aptitude, with media production of 113 liters, commercialization in laboratory, cooperative, fair free and informal commerce. Animal nutrition computes in fourteen different food management. The animals of the properties are in the preventive program of diseases and diseases, result obtained by veterinary interaction carried out by the program, as well as the conventional management. A livestock activity of the family producers of Muriaé is with low specialization, its base production is the production of milk, followed by secondary activities without increase of income, as the properties are with the technological deficiency in the use of the maximization of production of milk.