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Jornal da Tarde (1966-75): ideologia liberal e ditadura militar.
(Universidade Federal de São Carlos, 2004-04-06) Gazzotti, Juliana; Martins Filho, João Roberto
Secagem em leito fixo de sementes com mucilagem
(Universidade Federal de São Carlos, 2004-04-06) Prado, Manoel Marcelo do; Sartori, Dermeval José Mazzini
Attempting to contribute with the studies on mucilaginous seeds drying, the objective of this work is to study the simultaneous heat and mass transfer during drying in fixed bed of papaya seeds with and without mucilage. The physical-mathematical analysis used to predict the moisture and temperature profiles during drying was based on two-phases model, according to mass and heat balances in fluid and particulate phases. A moving coordinate system, that follows the bed contraction movement, was used to take into account the shrinkage phenomenon. Experimental investigations in a drying unit at bench scale were conducted to characterize the phenomenon of shrinkage and the physical properties of material as function of moisture content, as well as to determine the temperature and moisture content distributions, which were used to evaluate the model. The equations of thermodynamics equilibrium and heat and moisture transfer rate between the solid and fluid phases were obtained from specific studies. The model equations were solved using the finite difference method. Although the beds of mucilaginous seeds had the higher heat transfer rates, their drying rates were lower than those of non-mucilaginous seeds. Bed shrinkage was nearly 30% and 12% for seeds with and without mucilage, respectively, what is directly related to superficial characteristics of each particle and moisture gradients developed during drying. The analysis of the fixed bed drying of papaya seeds, which was based on the two-phases model, corroborated the importance of the bed shrinkage for a more accurate interpretation of heat and mass phenomena involved in drying of particles with high moisture contents. It is verified that the developed model is promising to predict the drying variable and that it must be tested in correlated studies.
Autoecologia do camorim, Centropomus undecimalis (Bloch, 1792), (Perciformes: Centropomidae) em ambiente hipersalino em Galinhos, RN, Brasil
(Universidade Federal de São Carlos, 2004-04-06) Mendonça, Maisa Clari Farias Barbalho de; Oliveira, José Eduardo Lino
Studies were done with the objective of knowing more about the ecology of the species Centropomus undecimalis (Bloch, 1792), regarding the aspects of population dynamics, age and growth, alimentary diet and reproduction. 1179 specimens (1122 males and 57 females), were captured in the Diamante Branco salt mine, Galinhos RN, the capture period happened between February 2001 and January 2003. Every month captures were done with the aid of fishing gears, looking for a representative sample of the population. The population dynamics showed a significant difference between the monthly relative frequencies distribution and for length classes, for males and females; and the same behavior occurred with the total weight distribution classes. The sexual proportion showed the prevalence of males during the whole period; being verified in the distribution by classes of length that there was an inversion among the sexes, the males pondered in classes of smaller length and the females in the classes of larger length. The growth parameters were obtained through the method of back calculation, being verified a low growth tax (K) and a high value of the asymptotic length. The analysis of the repletion Index and the medium repletion degree showed the prevalence of stomachs empty in the whole study period; the analysis of stomach content using the Index of Relative Importance and the alimentary Index revealed that the species is carnivore, with a tendency of piscivorous, with fishes, crustaceans, mollusks and insects in the diet. The Centropomus undecimalis reproduction was established using histological cuts, characterizing the stadiums of gonadal development for males and females. The oocyte and spermatogenic development observed allow inferring that the species is protandric hermaphrodite, through the simultaneous presence of spermatogenic tissues remains and ovarian tissues in development.