Activity of Mo(II) allylic complexes supported in MCM-41 as oxidation catalysts precursors

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Desempenho ponderal de bovinos Nelore suplementados com fontes alternativas de fósforo

O desempenho produtivo e a possível interferência do flúor sobre a saúde dos animais foram investigados em bovinos Nelore suplementados, por 866 dias, com distintas fontes alternativas de fósforo com diferentes relações fósforo:fluor (P:F). Os tratamentos experimentais foram: Controle negativo (CONTNEG, sem qualquer suplementação com P), fosfato bicálcico (FB 120:1, FB 30:1 e FB 10:1), fosfato monobicálcico (FMBC 60:1), superfosfato triplo (SFT 30:1) e fosfato de rocha de Cajati (FR 10:1). Foram utilizados 49 novilhos, desmamados aos oito meses de idade, castrados e com 230 kg de peso médio, distribuídos em sete piquetes com água e mistura mineral formulada sem P. A dieta padrão foi feita com bagaço de cana (0,03% de P) como volumoso e um concentrado contendo 0,239 % de P oferecido na base de 1% do peso dos animais para permitir um ganho de peso aproximado de 0,50 kg/dia. Até o dia 134, não houve diferença estatística entre os diversos lotes, inclusive para o tratamento CONTNEG, que não recebeu fósforo suplementar na dieta e ganhou 71,6 kg de peso ou 0,633 kg/dia. Após 866 dias de confinamento (2,37 anos), os animais suplementados com o fosfato bicálcico padrão (120:1) ganharam menos peso que os suplementados com as fontes FMCB 60:1, FB 30:1 e SFT 30:1. Até um ano de suplementação fosfórica com fosfato bicálcico padrão (120:1) artificialmente fluoretado com NaF ou com o fosfato de rocha não se detectou danos à saúde ou ao ganho de peso dos animais. As análises de fósforo nos ossos mostraram diferença estatística apenas entre o tratamento CONTNEG e os que tinham fosfato bicálcico. As concentrações de flúor nos ossos se mostraram intimamente associadas à quantidade de flúor disponível nas fontes utilizadas. Conforme a proporção P:F na dieta foi diminuindo, características relacionadas à fluorose dentária ficaram mais evidentes, sendo que os animais que receberam fontes com relação 10:1, apresentaram, ao final do experimento, dentes incisivos permanentes mal formados, quebradiços e com manchas esbranquiçadas.

Production of biodiesel by esterification of palmitic acid over mesoporous aluminosilicate Al-MCM-41

Biodiesel has been obtained by esterification of palmitic acid with methanol, ethanol and isopropanol in the presence of Al-MCM-41 mesoporous molecular sieves with Si/Al ratios of 8.16 and 32. The catalytic acids were synthesized at room temperature and characterized by atomic absorption spectrometry (AAS), thermal analysis (TG/DTA), X-ray diffraction (XRD), nitrogen absorption (BET/BJH), infrared spectroscopy (IR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The reaction was carried out at 130 degrees C whilst stirring at 500 rpm, with an alcohol/acid molar ratio of 60 and 0.6 wt% catalyst for 2 h. The alcohol reactivity follows the order methanol > ethanol > isopropanol. The catalyst Al-MCM-41 with ratio Si/Al = 8 produced the largest conversion values for the alcohols studied. The data followed a rather satisfactory approximation to first-order kinetics. (C) 2008 Elsevier Ltd. All rights reserved.

Preparation of different basic Si-MCM-41 catalysts and application in the Knoevenagel and Claisen-Schmidt condensation reactions

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Effect of the catalyst MCM-41 on the kinetic of the thermal decomposition of poly(ethylene terephthalate)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Thermogravimetric investigations during the synthesis of silica-based MCM-41

MCM-41 material was synthesized starting from hydrogel containing colloidal fumed silica, sodium silicate, cetyltetramethylammonium bromide (CTMABr) as surfactant, and distilled water as solvent. These reactants were mixed to obtain a gel with the following composition: 4SiO(2):1Na(2)O:1CTMABr:200H(2)O. The hydrogel with pH=14 was hydrothermally treated at 100 degreesC, for 4 days. Each day, the pH was measured, and then adjusted to 9.5-10 by using 30% acetic acid solution. Thermogravimetry was the main technique, which was used to monitor the participation of the surfactant on the MCM-41 nanophase, being possible to determine the temperature ranges relative to water desorption as well as the surfactant decomposition and silanol condensation.

Doses e fontes alternativas de nitrogênio no milho sob plantio direto em solo arenoso

The objective of this work was to evaluate the effect of nitrogen sources and rates on maize nutrition and grain yield under no-tillage system in sandy soil. The experiment was conducted in a Typic Quartzipsamment, in the city of Cassilandia, State of Mato Grosso do Sul, Brazil. A completely randomized block design was used in a factorial array 3x4 with four replicates. Treatments consisted of three sources [urea, extruded urea with starch (Starea), and ammonium sulfonitrate with nitrification inhibitor of 3,4-dimethylpyrazole-phosphate (Entec (R) 26)] and four rates (0, 45, 90 and 180 kg ha(-1)) of nitrogen, applied in side-dressing when the plants presented four and six expanded leaves. The nitrogen source affected N, K, and S concentration in the leaf, but did not interfere in the components of production and maize grain yield. Nitrogen application like ammonium sulfonitrate promoted higher concentrations of N, K and S in the maize leaf in relation to the urea, especially in the larger rates studied. Side-dressing nitrogen fertilization increased the number of ears per plant, number of grains per ear and grain yield, grown under no-tillage system in sandy soil, independent of the used source.

Uma nova metodologia de projeto e controle para o inversor Boost (CSI) monofásico, para o aproveitamento de fontes alternativas e renováveis de energia elétrica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Desempenho de bovinos nelore suplementados com fontes alternativas de fósforo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Isolamento de leveduras de um consórcio especializado e avaliação de seu potencial na produção de biossurfactantes em fontes alternativas de carbono

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Solubilização de fontes alternativas de potássio pelos ácidos húmicos, cítrico e casca de café

This study was to evaluate the solubility of nepheline syenite rocks and glauconite as alternative sources of K by organic humic acid arrays, citrus and coffee pods at various times from 0 to 180 days of incubation. The experiment was conducted in the fertility laboratory in the Department of Soil Science at the Federal University of Lavras in a completely randomized design with 90 treatments and 3 replications. The treatments were arranged in a factorial arrangement (2 x 3 x 7 + 3), 2 nepheline syenite rocks and glauconite incubated with water and 3 matrix organic humic acid, citric acid and coffee husk in six different incubation times of 0, 7, 15, 30, 75, 120 and 180 days, incubation were performed with the three above-mentioned organic matrix in increasing doses of 0, 1, 2, 5 and 10% humic acids and citric 0, 5, 10 20 and 40% for coffee husk. We evaluated the K2O content by different extractants soluble in 2% citric acid and water all treatments at all incubation times quoted above. Incubation and the application of organic matrix rocks nepheline syenite and generally glauconite provided a significant increase in solubility of K of the rocks studied in this work. Among the organic matrix has been observed that the coffee husk which provided the greatest release of K2O in both rocks mainly into the extractor 2% citric acid showed that the most efficient extraction K2O in all treatments.

Projeto e desenvolvimento de um sistema automatizado para monitoramento de fontes alternativas de energia

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Preparação pelo processo sol-gel de pós redispersáveis, filmes finos densos e materiais mesoporosos de óxido de titânio

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Parcelamento de fontes alternativas de nitrogênio no milho safrinha em sucessão à soja

Increasing out-of-season corn productivity is possible by the application of nitrogen fertilizers even when in succession to soybean. On the other hand, information concerning the best sources of nitrogen and ways of splitting the doses to be applied is still scarce. Having that in mind, an experiment was carried out viewing to evaluate the effects of sources of nitrogen and ways of splitting doses of those N fertilizers on out-of-season corn sown in succession to soybean cultivated in a no-tillage system. The experiment took place in Chapadão do Céu, state of Goiás, Brasil (latitude of 18°35’42’’ South, longitude of 52°47’59’’ West and mean altitude above sea level of 802 m) in an Acrutox. The experimental units were distributed in the field in accordance with a randomized complete block design, in a factorial scheme 3 X 5 + 1, with four replications. Three were the sources of N: urea, urea extruded with starch (Amireia®) and ammonium sulfonitrate with a nitrification inhibitor (Entec®) and five the ways of splitting the nitrogen dose : 90-0, 60-30, 45-45, 30-60, and 0-90 in which the first fraction was applied at sowing and the second in side dressing. In addition to those, there was a check treatment, without N. All plots received, at sowing, 12 kg ha-1 of N by the mixture NPK. The ways of splitting the N dose and the sources of N had no significant effect on the levels of N and S in the leaves, first ear height, the final plant population, the number of ears per plant, and the number of grains per ear. N in the Entec® form at the highest doses applied in side dressing resulted in the highest grain yield, independently of the way the N dose was split. Only in the form Entec® the dose of 90 kg ha-1 of N increased grain productivity by 9.6% in comparison with the check treatment.

Avaliação da qualidade de óleos compostos obtidos de fontes alternativas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)