Effect Of Nb
Mostrando 1-12 de 139 artigos, teses e dissertações.
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1. Synthesis and characterization of niobium-doped fish scale-derived hydroxyapatite by physical ultrasound interference
Abstract Fish scales of the Arapaima gigas (pirarucu) species were heat-treated to obtain natural hydroxyapatite (HAp), and it was doped with niobium (Nb) by physical ultrasound interference to confirm an effective route to the production of Nb-doped HAp powders. The effect of ultrasound application on doping was investigated. The structure of the powders wa
Cerâmica. Publicado em: 2021-03
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2. ELECTROCHEMICAL INCINERATION OF SHORT-CHAIN CARBOXYLIC ACIDS WITH NB‑SUPPORTED BORON DOPED DIAMOND ANODE: SUPPORTING ELECTROLYTE EFFECT INTO THE ELECTROGENERATED OXIDANT SPECIES (HYDROXYL RADICALS, HYDROGEN PEROXIDE AND PERSULFATE)
This work describes the electrochemical oxidation study of three short chain carboxylic acids (acetic, oxalic and formic 0.18 mol L-1) using different electrolysis conditions (electrolyte composition and current density) in an electrochemical reactor fitted with niobiumsupported/BDD electrode (Nb/BBD) as anode and titanium plate as cathode. The experiments w
Quím. Nova. Publicado em: 2020-03
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3. Effect of Welding Parameters on Nanostructured Fe-(C, B)-(Cr, Nb) Alloys
New nanostructured Fe-(Nb,Cr)-(C,B) multicomponent alloys have been developed for hardfacing application. They have better wear resistance than traditional Fe-Cr-C alloys. The nano-alpha-Fe, eutectic and hard carboborides phases of the weld metal usually show variations with the welding procedure. 6 test samples with different heat input were welded. It was
Mat. Res.. Publicado em: 20/01/2020
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4. Microstructural Evolution and Phase Transformation of a Ti-5Nb-5Al Alloy During Annealing Treatment
The microstructural evolution and phase transformation of a Ti-5Nb-5Al alloy during isothermal annealing treatment were studied in this paper. The microstructural evolution was analyzed by X-ray diffraction (XRD), scanning electron microscope (SEM) equipped with X-ray energy dispersive spectroscopy (EDS) and electron backscattering diffraction (EBSD). The fi
Mat. Res.. Publicado em: 05/12/2019
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5. Effect of Rolling Temperature on Microstructure and Mechanical Properties of a Nb-Mo Microalloyed Medium Mn Steel
Warm rolling of medium Mn steel is a promising technology to meet the needs of vehicle weight reduction and energy conservation while ensuring the safety for passengers. In this study, a novel Nb-Mo microalloyed 6.6Mn steel was subjected to a series of warm rolling tests at temperatures ranging from 630 to 690 ºC, based on the thermodynamic-based prediction
Mat. Res.. Publicado em: 11/11/2019
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6. Influence of Nb Content on Sensitization and Pitting Corrosion of Welded AISI 430 Ferritic Stainless Steel
Resumo Neste trabalho, o efeito da adição de Nb na sensitização e corrosão por pite de aço inoxidável ferrítico AISI 430 submetido à soldagem TIG foi investigado por caracterização microestrutural e técnicas eletroquímicas. As três regiões distintas do processo de soldagem, zona fundida, zona termicamente afetada e metal de base do aço AISI
Soldag. insp.. Publicado em: 07/10/2019
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7. Influence of Sintering Time on the PTCR Effect of Nb2O5-doped BaTiO3 Ceramics
The effects of the sintering time on the electrical properties and the positive temperature coefficient of resistance (PTCR) effect of Ba1.006(Ti1-xNbx)O3 (BTN) ceramics were investigated, which were sintered at 1190 ºC for 0.5-6 hours in a reducing atmosphere and then re-oxidized at 800 ºC for 1 hour. The results indicated that the sintering time affected
Mat. Res.. Publicado em: 16/09/2019
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8. Influence of Mechanical Cycling on Residual Strain in Superelastic Cu-Al-Be-Nb Alloys
The understanding of the stabilization mechanism of martensite used to obtain alloys with high hysteresis and the possibility of recovering this martensite (residual strain) by heating at temperatures higher than As and Af have been fundamental for application in bonding devices. One of the possibilities to enhance residual strain is through mechanical cycli
Mat. Res.. Publicado em: 15/07/2019
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9. Effect of Thermo-Mechanical Treatments on the Microstructure and Mechanical Properties of the Metastable β-type Ti-35Nb-7Zr-5Ta Alloy
In this work, theoretical composition design and thermo-mechanical treatments were combined in order to improve the mechanical compatibility of a biomedical β-type titanium alloy. By applying a composition design theory, cold rolling and low temperature aging, a metastable β-type Ti-35Nb-7Zr-5Ta (wt%) alloy with an elastic modulus of 47 GPa and a yield str
Mat. Res.. Publicado em: 29/10/2018
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10. Effect of Solid Solution + Double Ageing on Microstructure and Properties in the Layer by Layer of the Z-Y Interface of Inconel 718 alloys Fabricated by SLM
The microstructure in the Z-Y surface of Inconel 718 alloys fabricated by selective laser melting (SLM) shows the relatively homogeneous and irregular fine grain structure after the heat treatment process of 1050ºC solid solution + double ageing. A large number of bulk precipitates were observed on the grain boundary, and the typical dendritic crystallizati
Mat. Res.. Publicado em: 11/10/2018
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11. Influence of Small Content Elements Additions on the Glass Forming Ability of Zr-based Bulk Metallic Glasses Alloys
The present work reports investigation on the Glass Forming Ability (GFA) of Zr-based Bulk Metallic Glasses (BMG’s) by microalloying with early transition metals. GFA was measured as the amorphous fraction formed in samples with different diameters using optical microscopy (OM) and image analysis techniques. Samples with the highest GFA had their oxygen co
Mat. Res.. Publicado em: 06/09/2018
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12. Effect of Dy3+ Amount on the Structural and Luminescence Properties of LaNbO4:Dy3+ Phosphor Obtained by One-Step Spray Pyrolysis Process
In this study, Dy3+-doped LaNbO4 phosphors with a blue to white emission that can be tuned by varying the activator concentration were prepared by one-step spray pyrolysis process. According to the powder X-ray diffraction results, increasing Dy3+ concentration favored the tetragonal phase. Slight changes were observed in the recorded Raman spectra as a func
J. Braz. Chem. Soc.. Publicado em: 2018-03