Metal Oxides
Mostrando 1-12 de 131 artigos, teses e dissertações.
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1. Bimetallic Au-Pd/α-MoO3 Catalyst with High Oxygen Vacancies for Selective Oxidation of Cinnamyl Alcohol
Supported Au-Pd nanoparticles (NPs) have been extensively studied in alcohol oxidation reactions. However, few studies use reducible metal oxides as support, which can activate oxygen molecules and boost the selectivity of the reaction. In this work, Au-Pd NPs were supported on α-MoO3 and evaluated in the selective oxidation of cinnamyl alcohol without solv
Journal of the Brazilian Chemical Society. Publicado em: 2023
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2. 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
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3. THEORETICAL UNDERSTANDING OF MORPHOLOGICAL DISTRIBUTION OF HYDROGEN IN AMORPHOUS CALCIUM SILICATE HYDRATE
Determining the morphological distribution of hydrogen atoms in calcium silicate hydrate phase (C-S-H) is of great concern but challenging. In this work, based on the stoichiometric composition of (CaO)1.7(SiO2)(H2O)1.8, a series of amorphous Ca1.7•Si•(O)3.7-x•(OH)2x•(H2O)1.8-x models are constructed using Monte Carlo method, where x represents the m
Quím. Nova. Publicado em: 20/07/2020
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4. An Overview of the Photocatalytic H2 Evolution by Semiconductor-Based Materials for Nonspecialists
The solar-to-chemical energy conversion is promising to tackle sustainability challenges toward a global future. The production of H2 from sunlight represents an attractive alternative to the use of carboniferous fossil fuels to meet our energy demands. In this context, the water splitting reaction photocatalyzed by semiconductors that can be excited under v
J. Braz. Chem. Soc.. Publicado em: 2020-02
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5. BIODIESEL SYNTHESIS FROM WASTE COOKING OIL USING A VARIETY OF WASTE MARBLE AS HETEROGENEOUS CATALYSTS
Abstract The research article is based on biodiesel synthesis by the transesterification of waste cooking oil with methanol in the presence of heterogeneous catalysts prepared from different marble. Eight samples of marble were successfully converted into potential catalysts by calcination. The thermal treatment of waste marbles at 300oC-1000oC converted the
Braz. J. Chem. Eng.. Publicado em: 13/01/2020
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6. Characterization and Comparative Analysis of Corrosion Resistance of 4 High Manganese Steels Models in Aqueous Solution of NaCl
The liquefied natural gas volumes that currently need to be stored and/or transported require engineering to consistently develop materials that combine high mechanical strength and low manufacturing costs. The present work brings the study of four models of high manganese steels (non-commercials), to demonstrate the feasibility of being used in the petroche
Mat. Res.. Publicado em: 09/12/2019
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7. Proteins and Peptides at the Interfaces of Nanostructures
Abstract: The present review focuses on the proteins and peptides at the interfaces of nanostructured metals and semiconductors as a result of their use in synthesis in-situ and functionalization of nanostructures. We start the review with an introduction about the peculiar properties of nanostructured materials and their applications. In the following, the
An. Acad. Bras. Ciênc.. Publicado em: 25/11/2019
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8. DETERMINAÇÃO DE Al3+, Fe3+ E Cu2+ PRESENTES EM SOMBRAS DE MAQUIAGEM POR ESPECTROFOTOMETRIA UV-Vis: UMA PROPOSTA DE EXPERIMENTO CONTEXTUAL EM NÍVEL SUPERIOR DE ENSINO
Metallic oxides are used in cosmetic shadows formulations in order to highlight the area around the eyes, with different colors. Due to the close proximity to the eye mucosa, these products are a potential source of metal intoxication in human body. Based in this fact, several analytical methods to quantify metals in cosmetic shadows have been proposed in th
Quím. Nova. Publicado em: 02/05/2019
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9. Oxidative Dehydration of Glycerol over Molybdenum- and Vanadium-Based Catalysts
Surplus of glycerol production from the biodiesel industry has led to the search for glycerol conversion routes, the most common of which are dehydration and oxidative dehydration. Vanadium and molybdenum oxides were supported on γ-Al2O3 and their properties were analyzed through several characterization techniques, showing that the acidity increases after
J. Braz. Chem. Soc.. Publicado em: 08/04/2019
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10. De-NOx Performance and Mechanism of Mn-Based Low-Temperature SCR Catalysts Supported on Foamed Metal Nickel
A series of manganese-based catalysts supported on foamed metal nickel (FMN) with various Mn/Ni ratios was prepared for low-temperature selective catalytic reduction (SCR) of NO with NH3 (NH3-SCR). The effects of calcination temperature, amount of added Mn, optimal operating conditions, and H2O on the elimination of nitrogen oxides (de-NOx) performance of ca
J. Braz. Chem. Soc.. Publicado em: 2018-08
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11. Esfuerzo de corte en Interfaces Fe/Fe3O4
Abstract The mechanical stability of oxides formed on metallic alloys is a key concern in the determination of component susceptibility to the medium in contact and the applicability of the alloy to high temperatures and other extreme conditions. In this context, the energy of adhesion is a key parameter. Density functional Theory (DFT) and other atomistic m
Matéria (Rio J.). Publicado em: 19/07/2018
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12. Electrocatalytic Oxidation Removal of Phenol from Aqueous Solution with Metal Oxides Doped Carbon Aerogel
Metal oxides (manganese oxide, MnO, manganese dioxide, MnO2, copper oxide, CuO, zinc oxide, ZnO and nickel oxide, NiO) doped carbon aerogel (CA) were prepared and used as catalysts in heterogeneous oxidation of phenol from aqueous solution in a three-dimensional (3D) electrode reactor. Textural characterization of metal oxides doped CA showed that the metal
J. Braz. Chem. Soc.. Publicado em: 2018-04