Publications by authors named "Mariele S Nascimento"

Microwave-induced combustion (MIC) was proposed in this study for honey decomposition aiming for As, Cd, Hg, and Pb determination by inductively coupled plasma mass spectrometry (ICP-MS). Sample mass (up to 1.0 g), absorbing solution (0.

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Many efforts have been recently made to improve the digestion efficiency by using powerful equipment or by using an auxiliary reagent. In this work, an alternative method is reported, which explores a digestion system based on a single reaction chamber (SRC) technology pressurized with O for reducing the amount of acid, without impairing the digestion efficiency. Before digestion, the system was pressurized with compressed air (20 bar, 20% O) while the temperature was evaluated from 180 up to 270 °C.

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Oil emulsified in water is one of the most difficult mixtures to treat due to the good stability of emulsions, so there is a growing demand for more efficient methods for separating immiscible oil/water mixtures. In this context, the focus of this study was to obtain an adsorbent for the selective treatment of a simulated oily wastewater. To this aim, a modified hydrotalcite sample with hydrophobic and magnetic characteristics was prepared and characterized.

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Urban dust is a mixture of deposited particles from different sources usually linked to potentially toxic elements (PTEs). Despite the industrialization of many South American countries, little is known about the impact of particulate matter in large cities; these data are necessary to promote environmental policies aiming to protect human health. The main objective of this work was to evaluate the particle size distribution, composition, and environmental and human health risks of settled dust particles from Barranquilla, a Colombian Caribbean industrialized area.

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Microwave-induced combustion (MIC) system for further Cl, Br, and I determination in granola by inductively coupled plasma mass spectrometry (ICP-MS) was proposed. A high sample mass of granola was pressed as pellets and inserted into the proposed MIC system. Water and NHOH were evaluated as absorbing solutions.

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The halogen determination is important in view of their biological and environmental roles, but their determination has still been considered a challenge, especially at low concentrations. Therefore, a method for honey decomposition using microwave-induced combustion (MIC) combined with ion chromatography and conductimetric detection (for Cl, F, and S determination) or mass detection (for Br and I determination) (IC-CD-MS) is proposed. Trueness was evaluated by adding reference materials (RMs) or a standard solution in the sample.

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An alternative method for the determination of total chlorine content in hydroxypropyl cellulose (HPC) was applied, combining a recently developed system based on a combustion step followed by pyrohydrolysis reaction. Using this approach it the determination of total chlorine by inductively coupled plasma optical emission spectrometry (ICP-OES) without interferences was feasible. It overcame the limitations of European Pharmacopoeia (EP) method for HPC analysis regarding to the inability to determine total chlorine in HPC, once some chlorine compounds (e.

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Mancozeb (MZ), a manganese- and zinc-containing ethylene-bis-dithiocarbamate, is a broad-spectrum fungicide. Harmful effects of this fungicide have been reported in nontarget organisms via a not fully understood mechanism. has provided remarkable contributions for toxicological studies.

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Dairy industry wastewater contains high levels of organic matter, consisting mainly of fat, protein and products of their partial microbial decomposition. In the present study, the use of continuous electrocoagulation is proposed for the primary treatment of dairy wastewater. The electrochemical treatment was carried out in a continuous flow cell with aluminum electrodes.

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