Fixação de fósforo por um latossolo do estado de Minas Gerais

It: was studied the adsorption of R by samples of the horizons A1 (0-22cm), A3 (22-56cm) and B22 (155-200cm) of a Latossol f rom the State of Minas Gerais, Brasil, by mean of the isotherm of Langmuir. The maximum adsorption values (b) and selectivity constant (K) calculated from the linear pattern of the Langmuir equation were correlated with some physical and chemical: characteristics of the horizons. The main conclusion were as follows: a) The adsorption isotherm showed two definite regions: the one regarding to the high R fixation is in accordance with the Langmuir equation. b) It was observed big differences in respect to the values of maximum adsorption (b) as well as to the selectivity constant (K) .Foi estudada a adsorção do fósforo por amostras de três horizontes, A1 (0-22cm), A3 (22-56cm) e B22 (155-200cm), de um Latossolo do Estado de Minas Gerais por meio da isoterma de Langmuir. Os valores de adsorção máxima (b) e da constante de seletividade (K) calculados a partir da forma linear da equação de Langmuir foram correlacionados com algumas características físicas e químicas apresentadas pelos citados horizontes. Os resultados encontrados permitiram concluir que: a - As isotermas de adsorção mostraram duas regiões distintas: aquela em que o fosfato é fortemente retido foi convenientemente descrita pela equação de Langmuir. b - Em virtude da diversidade das características físicas e químicas dos horizontes houve grande variação nos valores de adsorção máxima (b) e da constante de seletividade (K)

Painéis sanduíches de poliéster reforçado com fibras de rami para aplicação na Construção Civil

RESUMO Neste trabalho foram produzidos e caracterizados mecanicamente compósitos de resina de poliéster reforçada com tecido bidirecional de fios de rami, com diferentes teores de reforço. Estes compósitos foram testados experimentalmente e numericamente como faces de painéis sanduíches formados com núcleos de bucha vegetal impregnada com resina de poliéster e poliestireno expandido - EPS. A caracterização mecânica dos materiais em estudo foi realizada em laboratório a partir de ensaios de tração e flexão, e simulação numérica pelo Método de Elementos Finitos (MEF). A microestrutura do compósito foi analisada por Microscopia Eletrônica de Varredura (MEV). A partir das propriedades mecânicas obtidas para os compósitos reforçados com tecido bidirecional de fios de rami e núcleos de EPS e bucha vegetal, observou-se viável a confecção de painéis sanduíches para aplicação na Construção Civil. Os compósitos com 50% de volume de fios de rami apresentaram as melhores propriedades mecânicas e foram usados como faces nos protótipos dos painéis. Os núcleos em estudo apresentaram bons resultados, com destaque para a bucha vegetal impregnada de resina poliéster, que apresentou maior rigidez e opções de confecção de painéis com maiores dimensões e mais delgados. O presente trabalho evidenciou o potencial das fibras vegetais para uso como constituintes dos compósitos poliméricos e núcleo dos painéis sanduíches e, portanto, revela uma nova alternativa de aproveitamento dessas fibras para aplicação no setor da construção

EFFICACY OF NITAZOXANIDE AGAINST Toxocara canis: LARVAL RECOVERY AND HUMORAL IMMUNE RESPONSE IN EXPERIMENTALLY INFECTED MICE

SUMMARY The efficacy of nitazoxanide (NTZ) against toxocariasis was investigated in an experimental murine model and results were compared to those obtained using mebendazole. Sixty male BALB/c mice, aged six to eight weeks-old, were divided into groups of 10 each; fifty were orally infected with 300 larvaed eggs of T. canisand grouped as follows, G I: infected untreated mice; G II: infected mice treated with MBZ (15 mg/kg/day) 10 days postinfection (dpi); G III: infected mice treated with NTZ (20 mg/kg/day) 10 dpi; G IV: infected mice treated with MBZ 60 dpi; G V: infected mice treated with NTZ 60 dpi; GVI: control group comprising uninfected mice. Mice were bled via retro-orbital plexus on four occasions between 30 and 120 dpi. Sera were processed using the ELISA technique to detect IgG anti- Toxocaraantibodies. At 120 dpi, mice were sacrificed for larval recovery in the CNS, liver, lungs, kidneys, eyes and carcass. Results showed similar levels of anti- ToxocaraIgG antibodies among mice infected but not submitted to treatment and groups treated with MBZ or NTZ, 10 and 60 dpi. Larval recovery showed similar values in groups treated with NTZ and MBZ 10 dpi. MBZ showed better efficacy 60 dpi, with a 72.6% reduction in the parasite load compared with NTZ, which showed only 46.5% reduction. We conclude that administration of these anthelmintics did not modify the humoral response in experimental infection by T. canis. No parasitological cure was observed with either drug; however, a greater reduction in parasite load was achieved following treatment with MBZ

Photoinduced Schottky Barrier in Photorefractive Materials

LGEP 2010 ID = 604International audienc

Photovoltaic effect in Bi2TeO5 photorefractive crystal

CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORFAPEG - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE GOIÁSWe report on the presence of a strong photovoltaic effect on nominally undoped photorefractive Bi2TeO5 crystals and estimated their Glass photovoltaic constant and photovoltaic field for lambda = 532 nm illumination. We directly measured the photovoltaic-based photocurrent in this material under lambda = 532 nm wavelength laser light illumination and compared its behavior with that of a well known photovoltaic Fe-doped Lithium Niobate crystal. We also show the photovoltaic current to strongly depend on the polarization direction of light. Holographic diffraction efficiency oscillation during recording and the behavior of fringe-locked running holograms in self-stabilized experiments are also demonstrated here as additional indirect proofs of the photovoltaic nature of this material.We report on the presence of a strong photovoltaic effect on nominally undoped photorefractive Bi2TeO5 crystals and estimated their Glass photovoltaic constant and photovoltaic field for lambda = 532 nm illumination. We directly measured the photovoltaic-based photocurrent in this material under lambda = 532 nm wavelength laser light illumination and compared its behavior with that of a well known photovoltaic Fe-doped Lithium Niobate crystal. We also show the photovoltaic current to strongly depend on the polarization direction of light. Holographic diffraction efficiency oscillation during recording and the behavior of fringe-locked running holograms in self-stabilized experiments are also demonstrated here as additional indirect proofs of the photovoltaic nature of this material.1071514CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORFAPEG - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE GOIÁSCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORFAPEG - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE GOIÁSSem informaçãoSem informaçãoSem informaçãoSem informaçã

Electron Paramagnetic Resonance Study of Ternary CuII Compounds with Glycine and Phenanthroline

We report electron paramagnetic resonance (EPR) measurements at 9 and 34 GHz, and room temperature (T), in powder and single crystal samples of the ternary compounds of copper nitrate or copper chloride with glycine and 1,10-phenanthroline [Cu(Gly)(phen)(H2O)]∙NO3∙1.5H2O (1) and [Cu(Gly)(phen)Cl]2∙7H2O (2). In compound 1 the copper ions are arranged in 1-D chains along one of the crystal axes connected by syn-anti carboxylate ligands, while in 2 the array is nearly 3-D and the connections involve H-bonds and stacking interactions. The angular variation of the squared g-factor and the line width were measured as a function of orientation of the magnetic field (B0) in three orthogonal crystal planes. In both compounds we observed one resonance without hyperfine structure for any magnetic field orientation which we attribute to the collapse of the hyperfine coupling and of the resonances of two chemically identical but rotated coppers in the unit cell, produced by exchange interactions. We analyze the results in terms of the structures of the compounds and of the chemical paths connecting neighbor copper ions which support the exchange interactions between neighbor spins in the lattice. Considering the collapse of the EPR signals of rotated sites in the lattices we are able to set lower  limits to the exchange interactions, which are supported by weak equatorial-apical carboxylate bridges in 1, and by paths containing hydrogen bonds and aromatic interactions in 2. Broadening due to dipole dipole couplings and hyperfine interactions are strongly reduced by these exchange couplings and their role in the EPR line width is more difficult to recognize.Fil: Santana, Ricardo C.. Universidade Federal de Goias; BrasilFil: Araújo, Anderson B. C.. Universidade Federal de Goias; BrasilFil: Carvalho, Jesiel F.. Universidade Federal de Goias; BrasilFil: Calvo, Rafael. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Física del Litoral; Argentina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Departamento de Física; Argentin

Nonlinear light-induced absorption In Bi2OeO5 photorefractive crystals

FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAIS - FAPEMIGCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESWe report on the light-induced absorption in undoped photorefractive Bi2TeO5 (BTeO) crystal. The so-called "two-center" model is shown to adequately describe the present material behavior. We demonstrate that nonlinear light-induced absorption occurs for high light intensities. The theoretical model allowed us to find out some material parameters from experimental data. We also investigate the effect of intensity and wavelength on the light-induced absorption.We report on the light-induced absorption in undoped photorefractive Bi2TeO5 (BTeO) crystal. The so-called "two-center" model is shown to adequately describe the present material behavior. We demonstrate that nonlinear light-induced absorption occurs for high light intensities. The theoretical model allowed us to find out some material parameters from experimental data. We also investigate the effect of intensity and wavelength on the light-induced absorption.311126772680FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAIS - FAPEMIGCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAIS - FAPEMIGCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESSem informaçãoSem informaçãoSem informaçãoSem informaçãoFrejlich, J., (2006) Photorefractive Materials: Fundamental Concepts, Holographic Recording, and Materials Characterization, , Wiley-InterscienceFöldvári, I., Denz, C., Péter Á., Petter, J., Visinka, F., Bismuth tellurite - A new material for holographic memory (2000) Opt. 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Opt., 5, pp. S500-S506Herth, P., Granzow, T., Schaniel, D., Woike Th., Imlau, M., Kratzig, E., Evidence for light-induced hole polarons in LiNbO3 (2005) Phys. Rev. Lett., 95, p. 067404Marinova, V., Ahmad, I., Goovaerts, E., Photo-induced absorption study of carrier dynamics in Ru-doped Bi12SiO20 crystals after nanosecond laser pulse excitation (2010) J. Appl. Phys., 107, p. 113106Luedtke, F., Buse, K., Sturman, B., Hidden reservoir of photoactive electrons in LiNbO3 crystals (2012) Phys. Rev. Lett., 109, p. 026603Evans, D.R., Shuymelyuk, A., Cook, G., Odoulov, S., Secondary photorefractive centers in Sn2P2S6:Sb crystals (2011) Opt. Lett., 36, pp. 454-456Buse, K., Light-induced charge transport processes in photorefractive crystals I: Models and experimental methods (1997) Appl. Phys. B, 64, pp. 273-291Brost, G.A., Motes, R.A., Rotgé, J.R., Intensity-dependent absorption and photorefractive effects in barium titanate (1988) J. Opt. Soc. Am. B, 5, pp. 1879-1885Kwak, C.H., Park, S.Y., Lee, E.-H., Intensity-dependent two-wave mixing at large modulation depth in photorefractive BaTiO3 crystal (1995) Opt. Commun., 115, pp. 315-322Shumelyuk, A., Wesner, M., Imlau, M., Odoulov, S., Wave mixing in nominally undoped Sn2P2S6 at high light intensities (2009) Appl. Phys. B, 95, pp. 497-503De Oliveira, I., Frejlich, J., Light intensity-dependent Debye screening length in undoped photorefractive titanosillenite crystals (2012) J. Appl. Phys., 112, p. 113523De Oliveira, I., Carvalho, J.F., Frejlich, J., Resonance running hologram velocity nonlinearity dependence upon light intensity in photorefractive crystals (2013) Appl. Phys. Lett., 102, p. 251913Carvalho, J.F., Fabris, Z.V., De Oliveira, I., Frejlich, J., Crystal growth of Bi2TeO5 by a double crucible Czochralski method (2014) J. Cryst. Growth, 401, pp. 795-797We acknowledge the financial support from Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP), Fundacao de Amparo a Pesquisa do Estado de Goias (FAPEG), Conselho Nacional de Desenvolvimento Cientfico e Tecnologico (CNPq), Coordenacao de Aperfeicoamento de Pessoal de Ensino Superior (CAPES), and Fundo de Apoio ao Ensino, Pesquisa e Extensao da Universidade Estadual de Campinas (FAEPEX)