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São José de Piranhas, Brazil

de Farias A.P.,Instituto Federal Of Alagoas | de Albuquerque A.W.,CECA | Filho G.M.,CECA | Reis L.S.,CECA
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2013

The present study was aimed to evaluate the productivity of Heliconia psittacorum x Heliconia pathocircinada, cv. Golden Torch, when submitted to different sources of organic manure. The experiment was conducted at Escola Agrotécnica Federal, in Satuba, Alagoas State (Brazil). The experimental design was randomized blocks with 5 replications and 10 treatments: T1(control, without fertilization; T2) mineral fertilizer; T3) farm yard manure; T4) chicken bedding; T5) filter cake; T6) urban garbage compound; T7) farm yard manure + mineral fertilizer; T8) chicken bedding + mineral fertilizer; T9) filter cake + mineral fertilizer; T10) urban garbage compound + mineral fertilizer. The following variables were evaluated: number of the tillers per clump, the beginning of the flowering, number of the flower stem per clump, length of flower stem, diameter of flower stem, length of bract, interval of the flowering, number of leaves per flower stem and leaf area of flower stem. The fertilization organomineral provided a significant increase in the variables: number of tillers per clump, length of flower stem, number of flower stem per clump, length of bract, floral stem, diameter of flower stem and leaf area, contributing also to the precocity harvest and smaller flowering interval, when compared with organic fertilizers and control. Source

da Silva G.L.,Federal University of Alagoas | da Silva G.L.,Instituto Federal Of Alagoas | Canabarro A.A.,Federal University of Alagoas | Canabarro A.A.,Boston University | de Lima Bernardo B.,Harvard University
Annals of Physics | Year: 2015

Motivated by experimental evidences of spectral broadening of partial coherent pulses emitted by a P2O5-doped Raman fiber laser in a silica fiber, we theoretically study the propagation of a partially coherent optical beam through a noninstantaneous media by using extensions of the nonlinear Schrödinger equation (NLSE) including a phase-diffusion model for the partially coherent beam. The finite response time of the medium is incorporated by means of the Debye relaxation model. The dispersion relation is analytically calculated, and the gain spectra together with relevant second-order statistical quantities are numerically computed. Moreover, we provide a complete description of how these statistical properties vary as a function of the delayed nonlinear response of the medium; specifically in the regime of fast nonlinear response in which modulation instability is not expected to occur for genuine incoherent pulses. © 2015 Elsevier Inc.. Source

Bedor C.N.G.,Federal University of Vale do Sao Francisco | Morais R.J.L.,Federal University of Vale do Sao Francisco | Cavalcanti L.S.,Federal University of Vale do Sao Francisco | Ferreira J.V.,Instituto Federal Of Alagoas | Pavao A.C.,Federal University of Pernambuco
Science of the Total Environment | Year: 2010

The aim of the present study was to investigate the carcinogenic potential of endosulfan and its metabolites through electronic parameters that characterize the action of carcinogens, i.e. descriptors such as electron affinity, Δ (HOMO-LUMO), dipole moments, electrostatic attraction, formation heat (Hf) and permeability of the cell membrane (c Log P). The results reveal that both endosulfan and its metabolites are electrophilic and have carcinogenic potential. Although there are few data on its carcinogenicity in the literature, the findings of the present study indicate that the use of this pesticide represents a risk to the health of the general population, especially rural workers. © 2010 Elsevier B.V. Source

Mello F.F.C.,University of Sao Paulo | Mello F.F.C.,Harvard University | Cerri C.E.P.,University of Sao Paulo | Davies C.A.,Royal Dutch Shell | And 6 more authors.
Nature Climate Change | Year: 2014

The effects of land-use change (LUC) on soil carbon (C) balance has to be taken into account in calculating the CO2 savings attributed to bioenergy crops1-3. There have been few direct field measurements that quantify the effects of LUC on soil C for the most common land-use transitions into sugar cane in Brazil, the world's largest producer 1-3. We quantified the C balance for LUC as a net loss (carbon debt) or net gain (carbon credit) in soil C for sugar-cane expansion in Brazil. We sampled 135 field sites to 1 m depth, representing three major LUC scenarios. Our results demonstrate that soil C stocks decrease following LUC from native vegetation and pastures, and increase where cropland is converted to sugar cane. The payback time for the soil C debt was eight years for native vegetation and two to three years for pastures. With an increasing need for biofuels and the potential for Brazil to help meet global demand4, our results will be invaluable for guiding expansion policies of sugar-cane production towards greater sustainability. © 2014 Macmillan Publishers Limited. All rights reserved. Source

Silva A.J.C.,Federal University of Alagoas | Silva Jr. J.G.,Instituto Federal Of Alagoas | Alves Jr. S.,Federal University of Pernambuco | Tonholo J.,Federal University of Alagoas | Ribeiro A.S.,Federal University of Alagoas
Journal of the Brazilian Chemical Society | Year: 2011

Dansyl-based fluorescent films were prepared by two different methods. In one of them, the surface of an indium tin oxide (ITO) electrode was coated with a film of chitosan and the polymer subsequently derivatized with dansyl chloride, whilst in the second method a film of dansylglycine was electrochemically deposited on the ITO surface. Atomic force microscopy (AFM) was employed to map the surfaces of the films. Comparison of the morphological, photochemical and electrochemical properties of these films indicated that the dansylglycine film electrodeposited on ITO exhibited electrochemical response, emitted a higher level of fluorescence, presented greater surface roughness and larger relative surface area in comparison with its dansyl chloride-chitosan counterpart. This behavior can be attributed to the higher number of active sites present in the well-organized and rough structure of the electrodeposited film in comparison with the chemically produced films. ©2011 Sociedade Brasileira de Química. Source

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