Cobalt
Mostrando 1-12 de 842 artigos, teses e dissertações.
-
1. An alternative route to extract nickel and cobalt from non-commercial laterite ore
Abstract Laterite ores, which represent around two-thirds of nickel reserves, became an important source of nickel and cobalt metals. The objective of the present study was to investigate the efficiency of a hybrid route to extract nickel and cobalt present in a laterite ore sample which was not commercially attractive to be processed through the current rou
REM - International Engineering Journal. Publicado em: 2022
-
2. Iron Cobaltite (FeCo2O4) Nanocatalysts for Water-Oxidation: Effects of Annealing Temperature on Catalytic Properties
The development of efficient, stable, and non-precious metal water oxidation catalysts (WOCs) is a matter of importance for sustainable energy research. In this work, iron cobaltite (FeCo2O4) nanoparticles were prepared by the coprecipitation method, and we present the effect of heat treatment (250, 350, 450, 650 and 900 °C) on the catalytic properties. Cat
Journal of the Brazilian Chemical Society. Publicado em: 2022
-
3. Analysis and evaluation of structural properties of Co3O4 microparticles obtained at low temperature
Abstract In the present research, the synthesis of cobalt oxide Co3O4 was carried out using the sol-gel technique with subsequent heat treatment at 225 and 235 °C. The final product obtained was characterized by X-ray diffraction (XRD), showing a pure crystalline phase of Co3O4, cell parameters a=b=c=8.071 Å, and a volume of 525.7 Å3. The particle size wa
Cerâmica. Publicado em: 2022
-
4. Metal-Supported Niobium Catalysts Investigation for Conversion of Bio-Renewable Glycerol to Organic Compounds
The glycerol oxidative dehydration to organic compounds, especially acrolein and acrylic acid, was studied over vanadium, molybdenum, and cobalt oxides supported on niobium oxide and niobium phosphate catalysts. At 300 °C, the glycerol conversion was 100% over all catalysts tested, and acrolein was the main product observed, without significant deactivation
Journal of the Brazilian Chemical Society. Publicado em: 2022
-
5. DETERMINATION OF TOTAL AND BIOACCESSIBLE ELEMENTS IN TEMPORARY ADHESIVE TATTOOS USED BY CHILDREN AND ADULTS
The presence of bioaccessible potentially-toxic elements in five different brands of temporary tattoos (packaged with bubble gums) aimed at children and three product brands used by young and adult audiences were analyzed in accordance with the Brazilian Organization of Technical Standards (ABNT) and International Organization for Standardization (ISO) for t
Química Nova. Publicado em: 2022
-
6. Kinetic study and thermodynamic equilibrium modeling of the Co(II) and Mn(II) bioadsorption using the Rhodococcus opacus strain
Abstract Microbial biomass is considered a renewable and environmentally friendly resource. Thus, the research conducted a kinetic study and thermodynamic equilibrium modeling of the cobalt (Co) and manganese (Mn) bioadsorption process using the Rhodococcus opacus (RO) strain as a biosorbent. The inactive biomass subjected to 0.1 M NaOH pretreatment was brou
REM - International Engineering Journal. Publicado em: 2022
-
7. Monitoring and health risk assessment of selected trace metals in wheat rice and soil samples
Abstract Wheat and rice constitute important cereal crops and any contamination may pose potential adverse impacts on human health. The study was conducted to determine eight trace metals, i.e. cadmium (Cd), copper (Cu), cobalt (Co), chromium (Cr), zinc (Zn), lead (Pb), nickel(Ni), manganese (Mn), in wheat, rice and soil samples collected from different citi
Food Sci. Technol. Publicado em: 2020-12
-
8. Telepsychiatry in Brazil during the COVID-19 pandemic: Did we exchange a walk-on part in a war for a lead role in a cage?
Abstract Wheat and rice constitute important cereal crops and any contamination may pose potential adverse impacts on human health. The study was conducted to determine eight trace metals, i.e. cadmium (Cd), copper (Cu), cobalt (Co), chromium (Cr), zinc (Zn), lead (Pb), nickel(Ni), manganese (Mn), in wheat, rice and soil samples collected from different citi
J. bras. psiquiatr.. Publicado em: 2020-12
-
9. Vale S.A .: Operação de Streaming de Cobalto
RESUMO O caso “Vale S.A. — Cobalt Streaming” descreve uma transação realizada na Vale, uma empresa de mineração brasileira e uma das mais importantes em seu segmento. A transação foi desenvolvida para reduzir o risco de um importante projeto para a expansão de uma mina na província de Newfoundland e Labrador, no Canadá. Ao fazer o streaming da
Rev. adm. contemp.. Publicado em: 2020-12
-
10. Design, Synthesis, and Application of Colored Cobalt Pigments (Pink, Blue, Green)
The combination of white or colorless oxides (MgO, Al2O3, ZnO) with colorant ions (Co2+) generates colored pigments (pink, blue, green). The color is caused by the insertion of the colorant ion in the respective crystal lattices (periclase, alumina, wurtzite), as verified by X-ray diffraction. Absorption spectra in the visible region show analogous triplet b
J. Braz. Chem. Soc.. Publicado em: 2020-11
-
11. Performance of Water Oxidation by 3D Printed Electrodes Modified by Prussian Blue Analogues
The water oxidation is the limiting step in the water-splitting process. Given this scenario, the development of new catalysts is essential in this field. The emergent demand is the use of Earth-abundant elements and catalysts with high performance under mild conditions. Because of this, catalysts such as Prussian Blue analogues (PBA) have been receiving a l
J. Braz. Chem. Soc.. Publicado em: 2020-11
-
12. Ischemia-modified albumin as a possible marker of oxidative stress in patients with telogen effluvium,
Abstract Background Telogen effluvium is the most common form of non-scarring alopecia characterized by diffuse hair loss. Ischemia-modified albumin is a marker of oxidative stress and inflammation. Objective The aim of this study was to compare the levels of ischemia-modified albumin of telogen effluvium patients with healthy controls. Methods Ninety-one
An. Bras. Dermatol.. Publicado em: 2020-08