Fermentação em estado sólido: uma alternativa para o aproveitamento e valorização de resíduos agroindustriais tropicais.

bitstream/CNPAT-2010/9607/1/Ct-102.pd

Dose-response curves of Lolium multiflorum biotypes resistant and susceptible to clethodim.

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Strange quark matter in explosive astrophysical systems

Explosive astrophysical systems, such as supernovae or compact star binary mergers, provide conditions where strange quark matter can appear. The high degree of isospin asymmetry and temperatures of several MeV in such systems may cause a transition to the quark phase already around saturation density. Observable signals from the appearance of quark matter can be predicted and studied in astrophysical simulations. As input in such simulations, an equation of state with an integrated quark matter phase transition for a large temperature, density and proton fraction range is required. Additionally, restrictions from heavy ion data and pulsar observation must be considered. In this work we present such an approach. We implement a quark matter phase transition in a hadronic equation of state widely used for astrophysical simulations and discuss its compatibility with heavy ion collisions and pulsar data. Furthermore, we review the recently studied implications of the QCD phase transition during the early post-bounce evolution of core-collapse supernovae and introduce the effects from strong interactions to increase the maximum mass of hybrid stars. In the MIT bag model, together with the strange quark mass and the bag constant, the strong coupling constant $\alpha_s$ provides a parameter to set the beginning and extension of the quark phase and with this the mass and radius of hybrid stars.Comment: 6 pages, 5 figures, talk given at the International Conference on Strangeness in Quark Matter (SQM2009), Buzios, Brasil, September 28 - October 2, 2009, to be published in Journal Phys.

Fungos potencialmente ocratoxígenos em café.

Micotoxinas. Fatores que influenciam a produção de micotoxinas. Influência da atividade de água. Fungos associados aos frutos e grãos de café. Fungos produtores de OTA. Ocratoxina em café. Alteração da qualidade provocada por fungos associados aos grãos de café. Interação da OTA e outras micotoxinas. Considerações finais.bitstream/item/65527/1/2003-DOC-0053.pd

Electron localization by a magnetic vortex

We study the problem of an electron in two dimensions in the presence of a magnetic vortex with a step-like profile. Dependending on the values of the effective mass and gyromagnetic factor of the electron, it may be trapped by the vortex. The bound state spectrum is obtained numerically, and some limiting cases are treated analytically.Comment: 8 pages, latex, 4 figure

Limit on suppression of ionization in metastable neon traps due to long-range anisotropy

This paper investigates the possibility of suppressing the ionization rate in a magnetostatic trap of metastable neon atoms by spin-polarizing the atoms. Suppression of the ionization is critical for the possibility of reaching Bose-Einstein condensation with such atoms. We estimate the relevant long-range interactions for the system, consisting of electric quadrupole-quadrupole and dipole-induced dipole terms, and develop short-range potentials based on the Na_2 singlet and triplet potentials. The auto-ionization widths of the system are also calculated. With these ingredients we calculate the ionization rate for spin-polarized and for spin-isotropic samples, caused by anisotropy of the long-range interactions. We find that spin-polarization may allow for four orders of magnitude suppression of the ionization rate for Ne. The results depend sensitively on a precise knowledge of the interaction potentials, however, pointing out the need for experimental input. The same model gives a suppression ratio close to unity for metastable xenon in accordance with experimental results, due to a much increased anisotropy in this case.Comment: 15 pages including figures, LaTex/RevTex, uses epsfig.st

Chiral phase transition in the presence of spinodal decomposition

The thermodynamics of a first order chiral phase transition is considered in the presence of spinodal phase separation within the Nambu-Jona-Lasinio (NJL) model. The properties of the basic thermodynamic observables in the coexistence phase are discussed for zero and non-zero quark masses. We focus on observables that probe the chiral phase transition. In particular, the behavior of the specific heat and entropy as well as charge fluctuations are calculated and analyzed. We show that the specific heat and charge susceptibilities diverge at the isothermal spinodal lines. We determine the scaling behavior and compute the critical exponent $\gamma$ of the net quark number susceptibility at the isothermal spinodal lines within the NJL model and the Ginsburg-Landau theory. We show that in the chiral limit the critical exponent $\gamma=1/2$ at the tricritical point as well as along the isothermal spinodal lines. On the other hand, for finite quark masses the critical exponent at the spinodal lines, $\gamma=1/2$, differs from that at the critical end point, $\gamma=2/3$, indicating a change in the universality class. These results are independent of the particular choice of the chiral Lagrangian and should be common for all mean field approaches.Comment: 12 pages, 11 figure