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Joao Pessoa, Brazil

The Federal University of Paraíba is a public university whose main campus is located in the city of João Pessoa, Paraíba, Brazil. Together with the Federal University of Campina Grande, it is the main university of the state of Paraiba, Brazil. UFPB offers degrees in areas such as the liberal arts , health science , engineering and technology , business, education and the fine arts . There are also campuses in Areia, Bananeiras and North Coast . Wikipedia.


Pedrosa I.A.,Federal University of Paraiba
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2011

We present a quantum description of electromagnetic waves propagating through time-dependent homogeneous nondispersive conducting and nonconducting linear media without charge sources. Based on the Coulomb gauge and the quantum invariant method, we find the exact wave functions for this problem. In addition, we construct coherent and squeezed states for the quantized electromagnetic waves and evaluate the quantum fluctuations in coordinate and momentum space as well as the uncertainty product for each mode of the electromagnetic field. © 2011 American Physical Society. Source


In this study honey samples produced by Melipona (Michmelia) seminigra merrillae, collected in seven counties distributed in the central and southern region of Amazonas state in Brazil, were analysed for their botanical origin, content and profile of phenolic compounds, and antioxidant and antimicrobial activities. Twenty-two pollen types were identified. The total phenolic content ranged from 17 to 66 mg GAE/g of extract; the highest contents were found in honeys produced from pollen types such as Clidemia and Myrcia. The antioxidant activity was higher in the samples that contained higher quantities of phenolic compounds. In relation to the antibacterial activity, samples CAD3, CAD4 and SAD3 presented the best results. Fourteen phenolic compounds were determined. Among them, we identified the flavonoid taxifolin, which has not previously been described in honeys from stingless bees, and we report the identification of catechol in Brazilian honey samples for the first time. Copyright © 2013 Elsevier Ltd. All rights reserved. Source


Bakke K.,Federal University of Paraiba
International Journal of Modern Physics A | Year: 2011

We consider a neutral particle with permanent electric dipole moment interacting with a field configuration induced by the noninertial effects of the FermiWalker reference frame in the presence of a disclination and discuss the influence of curvature on the Landau - He - McKellar - Wilkens quantization. © 2011 World Scientific Publishing Company. Source


Bakke K.,Federal University of Paraiba
Annals of Physics | Year: 2014

We investigate torsion and noninertial effects on a spin-1/2 quantum particle in the nonrelativistic limit of the Dirac equation. We consider the cosmic dislocation spacetime as a background and show that a rotating system of reference can be used out to distances which depend on the parameter related to the torsion of the defect. Therefore, we analyse torsion effects on the spectrum of energy of a nonrelativistic Dirac particle confined to a hard-wall potential in a Fermi-Walker reference frame. © 2014 Elsevier Inc. Source


We discuss the arising of bound states solutions of the Schrödinger equation due to the presence of a Coulomb-type potential induced by the interaction between a moving electric quadrupole moment and a magnetic field. Furthermore, we study the influence of the Coulomb-type potential on the harmonic oscillator by showing a quantum effect characterized by the dependence of the angular frequency on the quantum numbers of the system, whose meaning is that not all values of the angular frequency are allowed. © 2013 Elsevier Inc. Source

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