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Carbon based materials as novel redox mediators for dye wastewater biodegradation

Due to their large-scale production and extensive application, dyes have turned serious pollutants when improperly handled and disposed, creating grave public health and environmental problems. One of the problems that textile industry is facing is related with the incomplete exhaustion of dyes onto textile fibres from an aqueous dyeing process, and the need to implement innovative and sustainable effluent trea...

Nordeste Alentejano

The missing Rheic Ocean magmatic arcs: Provenance analysis of Late Paleozoic

Early Carboniferous turbiditic sedimentary rocks in synorogenic basins located on both sides of the Rheic suture in SW Iberiawere studied for provenance analysis. An enigmatic feature of this suture, which resulted from closure of the Rheic Ocean with the amalgamation of Pangea in the Late Carboniferous, is that there are no recognizable mid- to Late Devonian subduction-related magmatic rocks,which should have ...

The provenance of Late Ediacaran and Early Ordovician siliciclastic rocks in th...

U–Pb geochronology of detrital zircon from Late Ediacaran (Beiras Group greywackes) and Early Ordovician (Sarnelhas arkosic quartzites and Armorican quartzites of Penacova) sedimentary rocks of the southwest Central Iberian Zone (SW CIZ) constrain the evolution of northern Gondwana activepassive margin transition. The LAICPMS U–Pb data set (375 detrital zircons with 90–110% concordant ages) is dominated by Neop...

North-Gondwana assembly, break-up and paleogeography: U–Pb isotope evidence fro...

The Estremoz Anticline in the Ossa-Morena Zone (SW Iberia) includes upper Ediacaran detrital rocks uncon- formably overlain by lower Cambrian detrital and carbonate rocks. The spectra of detrital zircon U–Pb ages dominated by Cryogenian and Ediacaran ages (with a typical gap in Mesoproterozoic ages) of the upper Edi- acaran greywackes and lower Cambrian arkosic sandstones indicate provenance from sources placed...

Geologia de Portugal - Geologia Pré-Mesozóica de Portugal II.2.3. Maciço de Évora

O Maciço de Évora (ME) representa uma área com cerca de 60 km2 (Fig. 1) que se estende entre Montemor-o-Novo e Évora (Carvalhosa, 1983), localizada nos domínios ocidentais da Zona de Ossa-Morena (ZOM, Quesada e Munhá, 1990; Pereira et al., 2007; 2008, 2009a) e incluído no sector de Montemor-Ficalho (Oliveira et al., 1991). Os seus limites foram definidos por Carvalhosa (1983) como coincidentes a sudoeste com o ...

Detrital zircon from a late Paleozoic accretionary complex of SW Iberia (Varisc...

In this study we present new U-Pb ages of detrital zircons from greywackes and quartzites of the Pulo do Lobo Anticline (PLA) that have been interpreted to represent a Late Paleozoic accretionary complex in SW Iberia. The PLA separates the Ossa Morena Zone, which has a North- Gondwana affinity throughout Late Ediacaran and Early Paleozoic times, from the South Portuguese Zone, which is considered to be underlai...

Evaluation of ion exchange-modified Y and ZSM5 zeolites in Cr(VI) biosorption a...

The aim of this work was the evaluation of the performance of two zeolites with different structures (FAU and MFI) and acidity properties in the biosorption of Cr(VI) and catalytic oxidation of ethyl acetate. The starting zeolites, Y (FAU) and ZSM5 (MFI), were modified by ion exchange treatments with NaNO3 in order to obtain zeolites with different acidity and sodium content. A biosorption system consisting of ...

Electrocatalytic oxidation of oxalic and oxamic acids in aqueous media at carbo...

The electrochemical oxidation of oxalic and oxamic acids on multiwalled carbon nanotubes (CNT) and on monometallic (Pd and Pt) and bimetallic (Pd-Cu, Pt-Cu) catalysts supported on multiwalled carbon nanotubes was investigated using cyclic voltammetry. The electrodes were prepared by dispersion of the catalytic material on Toray carbon (CT) using a Nafion/water solution. The kinetic parameters of the reactions w...

The effect of nanotube surface oxidation in the electrical response of MWCNT/PV...

Carbon nanotubes / poly(vinylidene fluoride) composites were prepared using CNT with different oxidation and thermal treatments. The oxidation procedure leads to CNT with the most acidic characteristics that lower the degree of crystallinity of the polymer and contribute to a large increase of the dielectric constant. The surface treatments, in general, increase percolation threshold and decrease conductivity, ...