796 resultados para Green Star,
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The first quantitative analysis of phylogenetic relationships of green lacewings (Chrysopidae) is presented based on DNA sequence data. A single nuclear and two mitochondrial genes are used in the analysis: carbomoylphosphate synthase (CPS) domain of carbamoyl-phosphate synthetase-aspartate transcarbamoylase-dihydroorotase (CAD) (i.e. rudimentary locus), large subunit ribosomal gene (16S) and cytochrome oxidase I (COI). This study represents the first use of the CAD gene to investigate phylogenetic relationships of the lacewings. DNA sequences for 33 chrysopid species from 18 genera, representing all subfamilies and tribes, were compared with outgroups sampled from families Hemerobiidae, Osmylidae and Polystoechotidae. Parsimony analyses of the combined data set recovered all of the previously established subfamilial and tribal groups as monophyletic clades (although relatively weakly supported) except Apochrysinae sensu lato. The enigmatic Nothancyla verreauxi Navas has historically been difficult to place in a subfamily group based on morphological characteristics; molecular data presented herein do not adequately resolve this problem.
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We report on light-emitting devices based on a green-phosphor compound (Mn-doped zinc silicate, Zn2SiO4: Mn) dispersed in a conductive polymeric blend (poly-o-methoxyaniline/polyvinylene fluoride, POMA/PVDF-TrFE). The devices exhibited high luminance in the green, good stability and homogeneous brilliance over effective areas up to 5 cm(2). The electroluminescence (EL) spectrum presented essentially the same characteristics as the photoluminescence (PL) and cathodoluminescence spectra, indicating that the light emission originates from decay of the same excited species, regardless of the excitation source. Operating characteristics were analyzed with current density - voltage (J - V) and luminance voltage ( L - V) curves to investigate the nature of the electroluminescence of the active material, which is still not completely understood.
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The measurement of sulfur dioxide in air at the parts-per-billion level is described. The experimental arrangement consists of two optical fibers placed on opposite sides of a liquid droplet of malachite green solution. After light has been passed through the droplet, the transmitted light is measured by a referenced photodetection arrangement. The light used in this absorption process is from a monochromatic source (lambda(max) 625 nm). This arrangement permits the variation of color in the droplet to be measured. The sulfur dioxide in the sample is collected by the droplet; it reacts with malachite green resulting in a colorless dye. The decoloration of the solution is proportional to the concentration of sulfur dioxide sampled. The signal depends on the sample flow rate. The present technique is simple, inexpensive, and permits a fast and near real time measurement while consuming very little reagent, (C) 1999 Academic Press.
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The Green function for a spin-1/2 charged particle in the presence of an external plane wave electromagnetic field is calculated by algebraic techniques in terms of the free-particle Green function.
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We prove the equivalence of many-gluon Green's functions in the Duffin-Kemmer-Petieu and Klein-Gordon-Fock statistical quantum field theories. The proof is based on the functional integral formulation for the statistical generating functional in a finite-temperature quantum field theory. As an illustration, we calculate one-loop polarization operators in both theories and show that their expressions indeed coincide.
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Blue-green and red photoluminescence (PL) emission in structurally disordered CaTiO3:Sm (CT:Sm) powders was observed at room temperature with laser excitation at 350.7 nm. The perovskite-like titanate CT:Sm powders prepared by a soft chemical processing at different temperatures of annealing were structurally characterized by X-ray diffraction (XRD) and X-ray absorption near-edge structure (XANES). The results indicate that the generation of the broad PL band is related to order-disorder degree in the perovskitelike structure. (c) 2006 Elsevier B.V. All rights reserved.
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An intense and broad visible photoluminescence (PL) band was observed at room temperature in structurally disordered PbWO4 thin films. The scheelite lead tungstate (PbWO4) films prepared by the polymeric precursor method and annealed at different temperatures were structurally characterized by means of x-ray diffraction and atomic force microscopy analysis. Quantum-mechanical calculations showed that the local disorder of the network modifier (Pb) has a very important role in the charge transfer involved in the green PL emission. The experimental and theoretical results are in good agreement, both indicating that the generation of the intense visible PL band is related to simultaneous structural order and disorder in the scheelite PbWO4 lattice.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The aim of this work was evaluating the performance of several cultivars of green corn for consumption 'in natura' in different planting dates. The first planting date was on May 26th, and the others, every 40 days. The hybrids (treatments) were: AG-1051, Agroeste 1567, BM-3061, Prezoto-32D10, PL-6880, BX-1382 and GNZ-2004. The following characteristics were evaluated: production, commercial ears weight without husk, commercial ears number, commercial ears diameter and length, male flowering, plant height and height of ear corn insertion. The cultivars AG1051, Agroeste 1567 and BM 3061 presented the best results compared to the others and they should be used in green corn production for ` in natura' consumption in Passos County, MG.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)