5 research outputs found

    Rice Husk Ash Modified with Vanadium Pentoxide

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    Rice husk collected in Barreiras City, Bahia, Brazil was converted to rice husk ash (RHA) by acidic or basic leaching, followed by calcination. The resulting RHA was modified with vanadium pentoxide (2, 5, or 10 mass% of V2O5).  The modified RHA samples were characterized by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). RHA exhibited FTIR bands associated with silica. After modification of acid-leached RHA with vanadium, the XRD data indicated the formation of V2O5 phases. Base-leached RHA modified with vanadium pentoxide showed the presence of the V2O5 phase only in the sample containing 10 mass% V2O5. The FTIR data indicated the formation of cristobalite, where bands associated with Si-O-V interactions were observed only for the sample with 10 mass% V2O5 prepared with acid-leached RHA. DOI: http://dx.doi.org/10.17807/orbital.v9i2.91

    Remoção de Carbofurano em Água Empregando Resíduos Agroindustriais como Adsorventes

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    In this study aimed to evaluate the possibility of using industrial boiler ash and rice husk ash in removing the commercial pesticide (carbofuran) in aqueous solution. These solids were collected in the Barreiras/BA, were heat treated and characterized by XRD and FT-IR. The adsorption experiments were performed in batch and the carbofuran removal was quantified using the spectrophotometry in the UV region. XRD data showed high silica content in boiler ash, which was reinforced by FT-IR analyses, showing the band FT-IR associated with presence of silica. In the FT-IR analysis of rice husk ash, this band relative to silica also were observed. The potential of adsorption of the ash industrial boiler and rice husk ash was verified obtaining significant results in the removal of carbofuran at low concentrations (2 mg/L), showing 100% of removal of pesticides from 720 min, used the ash industrial boiler, giving these materials a promising character as adsorbents. In the kinetic study of carbofuran adsorption, the mechanism of pseudo-second-order was better adjusted using the RHA as adsorbent, with a correlation coefficient (R2) of 0.997. The adsorption equilibrium was adjusted better to model of adsorption isotherm of Freundlich with a correlation coefficient of 0.999. DOI: http://dx.doi.org/10.17807/orbital.v1i1.71

    Rice Husk Ash Modified with Vanadium Pentoxide

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    Rice husk collected in Barreiras City, Bahia, Brazil was converted to rice husk ash (RHA) by acidic or basic leaching, followed by calcination. The resulting RHA was modified with vanadium pentoxide (2, 5, or 10 mass% of V2O5).  The modified RHA samples were characterized by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). RHA exhibited FTIR bands associated with silica. After modification of acid-leached RHA with vanadium, the XRD data indicated the formation of V2O5 phases. Base-leached RHA modified with vanadium pentoxide showed the presence of the V2O5 phase only in the sample containing 10 mass% V2O5. The FTIR data indicated the formation of cristobalite, where bands associated with Si-O-V interactions were observed only for the sample with 10 mass% V2O5 prepared with acid-leached RHA. DOI: http://dx.doi.org/10.17807/orbital.v9i2.91

    Bilateral cheiloschisis in bovine - A case report

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    ABSTRACT. Caldas S.A., Nogueira V.A., Lima A.E.S., Aragão A.P., d’Avila M.S., Santos A.M., Miranda I.C., Costa S.Z.R. & Peixoto T.C. [Bilateral cheiloschisis in bovine - A case report.] Queilosquise bilateral em bovino - Relato de caso. Revista Brasileira de Medicina Veterinária, 36(1):55-59, 2014. Departamento de Medicina e Cirurgia Veterinária, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, BR 465 Km 7, Seropédica RJ 23890-000, Brasil. E-mail: [email protected] A case of bilateral queilosquise in a cattle two years old was reported. Clinically, there was cachexia, difficulty in grasping food and water intake. The clinical examination revealed that the nasal orifices were discontinuous with the upper lip, which allowed communication between the nostrils and mouth in its rostral portion, crowding of incisors (tweezers), as well as exposure of medium and the 2nd corner and of the tongue. In this case, the bilateral queilosquise was the result of flaws in fusion of the maxillary process and the medial nasal process and its surroundings, probably due to mineral deficiencies of pregnant cow. This pathogenesis was suggested by excluding other possible causes, the knowledge of the existence of mineral deficiencies in the region where the event occurred and bad nutritional status of pregnant female
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