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The effect of shredding and particle size in physical and chemical processing o...
Oliveira, Paula C.; Taborda, F. Charters; Nogueira, C. A.; Margarido, F.Circuit boards present in most electric and electronic devices are very important components, which should be removed during sorting and dismantling operations in order to allow further adequate treatment for recovering valuable metals such as copper, nickel, zinc, lead, tin and rare elements. This recovery can be made by physical and chemical processes being size reduction by shredding the first step. In this ...
The effect of shredding and particle size in physical and chemical processing o...
Oliveira, Paula C.; Taborda, F. Charters; Nogueira, C. A.; Margarido, F.
Physical and chemical processing of printed circuit boards waste
Oliveira, Paula C.; Taborda, F. Charters; Margarido, F.; Nogueira, C. A.A recycling process for PCB’s is being studied, based on physical processing and hydrometallurgical treatment. PCB’s waste was shredded in a lab cutting mill, resulting a grinded material with 90% (weight) with particle size less than 2.1 mm and an average particle diameter of 1.2 mm. Chemical analysis of granulometric fractions showed that the base metals like Cu, Zn, Pb and Sn concentrated mainly in intermedi...
Leaching studies for metals recovery from printed circuit boards scrap
Oliveira, Paula C.; Cabral, Marta; Taborda, F. Charters; Margarido, F.; Nogueira, C. A.In this paper, the leaching behavior of the major metals present in printed circuit boards waste is evaluated, aiming at its recycling by hydrometallurgy. Several leachants were compared (sulfuric, hydrochloric and nitric acids, at 2 M H+ concentration), at temperatures of 25ºC and 90ºC and 4 hours of reaction time. Sulfuric acid leaching was not very promising concerning metals dissolution being only effective...
Localização anatómica das lesões responsáveis pelos diferentes padrões de respo...
Caldas, Alexandre Castro; Antunes, N. Lobo; Botelho, M. A. Silveira; Trindade, A. Monteiro; Grosso, J. Teixeira; Ferro, José M.; Marques, José BravoAplicaram-se duas provas de audição dicótica a 51 doentes com tumores dos hemisférios cerebrais com locaiizações diversas. Os resultados obtidos estão de acordo um o modelo fisio-patológico previamente proposto. Salienta-se a dissociação de resultados obtidos com as duas provas (dígitos e palavras). ------ ABSTRACT ------ Fifty one putients with tumors of the cerebral hemispheres were tested with two different ...
A perturbação das capacidades construtivas nos doentes afásicos
Ferro, José M.; Caldas, Alexandre Castro; Grosso, J. Teixeira; Taborda, F.; Marques, José BravoInexistente
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