EM - Escola de Minas
URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/6
Notícias
A Escola de Minas de Ouro Preto foi fundada pelo cientista Claude Henri Gorceix e inaugurada em 12 de outubro de 1876.
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2 resultados
Resultados da Pesquisa
Item Tectonic control of erosion in the southern Central Andes.(2018) Val, Pedro Fonseca de Almeida e; Venerdini, Agostina L.; Ouimet, William; Alvarado, Patricia; Hoke, Gregory D.Landscape evolution modeling and global compilations of exhumation data indicate that a wetter climate, mainly through orographic rainfall, can govern the spatial distribution of erosion rates and crustal strain across an orogenic wedge. However, detecting this link is not straightforward since these relationships can be modulated by tectonic forcing and/or obscured by heavy-tailed frequencies of catchment discharge. This study combines new and published along-strike average rates of catchment erosion constrained by 10Be and river-gauge data in the Central Andes between 28◦S and 36◦S. These data reveal a nearly identical latitudinal pattern in erosion rates on both sides of the range, reaching a maximum of 0.27 mm/a near 34◦S. Collectively, data on topographic and fluvial relief, variability of rainfall and discharge, and crustal seismicity suggest that the along-strike pattern of erosion rates in the southern Central Andes is largely independent of climate, but closely relates to the N–S distribution of shallow crustal seismicity and diachronous surface uplift. The consistently high erosion rates on either side of the orogen near 34◦S imply that climate plays a secondary role in the mass flux through an orogenic wedge where the perturbation to base level is similar on both sides.Item Application of sodium - and biogenic sulfide to the precipitation of nickel in a continuous reactor.(2013) Gonzaga, Flávia Donária Reis; Silva, Adarlêne Moreira; Cunha, Emmanoelle Cintra da; Leão, Versiane AlbisAttention has been focused in recent decades upon the precipitation of metal sulfides from acid mine drainage (AMD) and pregnant leach solutions, due to the advantages of the sulfide precipitation process over traditional methods employing hydroxides. The aim of this work was thus to explore Technologies for the precipitation of valuable metals, such as nickel using such sulfides (as either Na2S or biogenic sulfide). The recovery of nickel sulfide was improved when the initial pH of the solution containing each metal was set to 7. In such a condition the removal efficiency of nickel was 99.9%, corresponding to a residual level of 0.13 mg /L for nickel in solution. Kinetic parameters for precipitation were determined from the particle size distributions (produced in an MSMPR reactor) using the method of moments, where the growth and nucleation rates, as well the agglomeration kernel, were calculated. The precipitation of nickel at an initial pH of 7 showed a nucleation rate value of 8.16 x 1018#m^-3 s^-1, the highest volumetric growth rate (1.03 x 10^1 um^-3 s^-1) and agglomeration kernel of 9.71 x 10^-23m3 #^-1 s^-1. The biogenic sulfide was a suitable alternative to sodium sulfide for nickel removal. Both sodium sulfide and biogenic sulfide can be utilized to precipitate nickel as millerite (NiS), allowing the effluent compliant with environmental legislation.