Aluminum Oxides
Mostrando 1-12 de 48 artigos, teses e dissertações.
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1. 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
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2. Towards Qualification of Friction Stir Welding to AA5083-O and AA5052-O Aluminum Alloys
Friction Stir Welding (FSW) is an excellent alternative for joining dissimilar and similar materials in comparison to conventional welding processes. In this sense, this work aims at qualifying FSW to similar AA5083-O and AA5052-O aluminum alloys, with 6.35 mm thickness, in a CNC machining center. Therefore, four welding experiments were undertaken. At first
Mat. Res.. Publicado em: 13/01/2020
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3. 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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4. Análises de dosagens de concreto asfáltico do tipo Pré Misturado a Frio (PMF) utilizando Resíduos da Construção e Demolição de obras (RCD)
RESUMO Na construção civil, um problema ambiental recorrente é a geração e disposição de Resíduos de Construção e Demolição (RCD) de obras. A utilização do RCD como agregados na composição de concreto asfáltico, do tipo Pré Misturado a Frio (PMF), torna possível a execução de pavimentos rodoviários de baixo tráfego. Diante desses fatos
Matéria (Rio J.). Publicado em: 25/11/2019
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5. Validation of a Standard Operating Procedure (SOP) for Forensic Soils Investigation in Brazil
ABSTRACT Soil traces are useful as forensic evidence due to their potential to transfer and adhere to different types of surfaces on a range of objects or persons. Several works have been developed in forensic soils, under different analytical approaches. However, in Brazil, only the researches from the Group of the Federal University of Paraná have develop
Rev. Bras. Ciênc. Solo. Publicado em: 09/09/2019
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6. CHARACTERIZATION OF SILICON-ALUMINUM-ZIRCONIUM OXIDE OBTAINED BY THE SOL-GEL PROCESS
A new silicon-aluminum-zirconium ternary oxide (SiO2/Al2O3/ZrO2) was prepared by the sol-gel method followed by one-step washing with absolute ethanol or two-step washing with absolute ethanol followed by ultra-pure water. Both ternary oxides presented high surface area (over 340 m2 g-1). The binding energy values for Zr3d and Al2p levels showed the insertio
Quím. Nova. Publicado em: 18/07/2019
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7. Effectiveness of Arsenic Co-Precipitation with Fe-Al Hydroxides for Treatment of Contaminated Water
ABSTRACT Wastewater treatment is a challenging problem faced by the mining industry, especially when mine effluents include acid mine drainage with elevated arsenic levels. Iron (hydr)oxides are known to be effective in removal of As from wastewater, and although the resulting compounds are relatively unstable, the presence of structural Al enhances their st
Rev. Bras. Ciênc. Solo. Publicado em: 29/03/2018
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8. Chemical and mineralogical characterization of silicon manganese iron slag as railway ballast
Abstract In nature, metal ores such as iron, lead, aluminum and others are found in an impure state, sometimes oxidized and mixed with silicates of other metals. During casting, when the ore is exposed to high temperatures, these impurities are separated from the molten metal and can be removed. The mass formed by these compounds is slag. Slag is the co-prod
REM, Int. Eng. J.. Publicado em: 2017-12
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9. A Model for the Formation of Niobium Structures by anodization
The fluoride use for anodizing electrolytes has been primarily responsible for the formation of nanoporous oxides at valve metals, except aluminum, since it causes a dissolution process. This study presents the formation of an oxide model according to the following anodizing parameters: 100 V, 12.73 mA/cm2, room temperature and the niobium samples anodized i
Mat. Res.. Publicado em: 25/05/2017
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10. Clays for Brick Manufacturing in Actopan, Hidalgo: Physical, Chemical and Mineralogical Characterization
Samples of clays from Actopan, Hidalgo employed in brick manufacturing are physical, chemical and mineralogical characterized. Transmitted polarized light microscopy showed a uniform particle size with grain morphology characteristic of euhedral crystals with quartz, feldspars, nontronite, and iron oxides particles. Scanning Electron Microscopy revealed 75 �
Mat. Res.. Publicado em: 11/05/2017
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11. Chemical-Mineralogical Characterization of Magnetic Materials from Magnetic Soils of the Southern Espinhaço Mountain Chain and of the Upper Jequitinhonha Valley, State of Minas Gerais, Brazil
ABSTRACT In the Southern Espinhaço Mountain Chain and in the Upper Jequitinhonha Valley, magnetic soils, in different pedogenetic stages, are found to be forming over intrusions of basic lithology. The essential chemical and mineralogical properties of samples from magnetic soil profiles from those two physiographic environments in the state of Minas Gerais
Rev. Bras. Ciênc. Solo. Publicado em: 27/03/2017
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12. Gas-Phase Conversion of Glycerol to Acetol: Influence of Support Acidity on the Catalytic Stability and Copper Surface Properties on the Activity
Mesoporous mixed copper-aluminum oxides and copper-silicon oxides were synthesized with polymeric precursors route in order to evaluate the effect of the support acidity on the catalytic stability due to the carbon deposit and the copper surface characteristics on the catalytic activity for the gas-phase conversion of glycerol to acetol. The samples were cha
J. Braz. Chem. Soc.. Publicado em: 2016-12