Rare Earth Elements
Mostrando 1-12 de 58 artigos, teses e dissertações.
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1. Selective formation of neodymium phosphate from iron-neodymium magnet waste
Abstract Neodymium-iron-boron alloy, Nd2Fe14B, is used as a material for magnets. Neodymium is one of the valuable and expensive rare earth elements and is often recovered to reduce costs and environmental impact. Recently, a method for recovering neodymium as neodymium phosphate from mixed solutions was reported. This method was very useful because the main
Cerâmica. Publicado em: 2022
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2. Upconversion 3D Printed Composite with Multifunctional Applications for Tissue Engineering and Photodynamic Therapy
Upconversion nanoparticles (UCNPs) are suitable materials for bioapplications due to their ability to emit visible light under near infrared (NIR) excitation, in the biological transparency range. Polycaprolactone(PCL)-based scaffolds are widely used in tissue engineering in combination with inorganic compounds to improve bioactivity and osteoconductive prop
J. Braz. Chem. Soc.. Publicado em: 2020-04
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3. Separation of gadolinium and europium from chloride media by the solvent extraction technique
Abstract Obtaining rare earth elements (REE) is a complicated task, due mainly to the difficulty of separating and purifying them. Solvent extraction is the most widely used technique for separating REE, and the most common extractants used are organophosphorus acids. The low selectivity of this technique leads to the need for a high number of extraction cel
REM, Int. Eng. J.. Publicado em: 2020-03
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4. Application of the fundamental parameter method to the assessment of major and trace elements in soil and sediments from Osamu Utsumi uranium mine by WDXRF
Abstract Wavelength dispersive X-ray fluorescence spectrometry (WDXRF) is a suitable technique for the characterization of contaminated mining sites, providing a quick and reliable screening for areas of significant contamination. This study established and validated a non-destructive methodology for quantitative simultaneous determination of major and minor
REM, Int. Eng. J.. Publicado em: 16/09/2019
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5. Geochemistry, Sm-Nd isotopes and SHRIMP U-Pb geochronology of the Morro do Coco Granite (RJ, Brazil): another piece of the post-collisional magmatism of the Ribeira Belt
Abstract The Morro do Coco granite (MC) is a post-collisional intrusive body that was emplaced at Ribeira Belt, in the Cambro-Ordovician, succeeding the final stages of the Gondwana supercontinent amalgamation. This unit requires more studies, contrasting with similar best investigated occurrences of the central Ribeira Belt. This work presents a detailed in
Braz. J. Geol.. Publicado em: 12/09/2019
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6. Geochemistry and Spatial Variability of Rare Earth Elements in Soils under Different Geological and Climate Patterns of the Brazilian Northeast
ABSTRACT Growth in the agricultural and industrial sectors has increased the demand for rare earth elements (REEs) in the production of technological devices and fertilizers. Thus, the accumulation of these elements in the soil has become an environmental concern. Here, we aim to determine the natural contents of REEs in soils derived from different parent m
Rev. Bras. Ciênc. Solo. Publicado em: 02/07/2018
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7. Green Processing of Strategic Elements Based on Magnetic Nanohydrometallurgy
Magnetic nanohydrometallurgy (NHM) is a new process based on engineered superparamagnetic nanoparticles capable of performing as complexing agents for extracting and recovering strategic metals from mineral sources and urban wastes, as well as for removing hazardous elements from contaminated water. Its principles and application are reviewed in this paper.
J. Braz. Chem. Soc.. Publicado em: 2018-05
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8. Geology, geochemistry and petrology of basalts from Paraná Continental Magmatic Province in the Araguari, Uberlândia, Uberaba and Sacramento regions, Minas Gerais state, Brazil
Abstract: This study covers the region between the cities of Sacramento and Araguari/Uberlândia (Minas Gerais State, Brazil), where basalt flows from the Paraná Continental Magmatic Province outcrop. The investigated rocks present tholeiitic signature, with high titanium content, and are classified as Pitanga magma-type. The preserved basalt thickness is b
Braz. J. Geol.. Publicado em: 22/02/2018
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9. Determination of Rare Earth Elements in Some Flower Herb Teas and their Infusions
The aim of this study was to determine the sixteen rare earth elements (REEs) in twelve types of popular flower herb teas and their infusions consumed in China. Microwave-assisted acid digestion was used for all of the samples, and the contents of these elements were determined by inductively coupled plasma mass spectrometry (ICP-MS). The concentrations of R
J. Braz. Chem. Soc.. Publicado em: 2017-10
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10. Rare Earth Element Concentrations in Brazilian Benchmark Soils
ABSTRACT: Studies regarding background concentrations of rare earth elements (REEs) are scarce and have mainly focused on a limited number of soil types from the northern hemisphere. The aim of this study was to determine REE concentrations in thirty-five benchmark soils of Brazil. Composite soil samples were taken from areas under native vegetation or with
Rev. Bras. Ciênc. Solo. Publicado em: 15/12/2016
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11. Simultaneous Determination of Rare Earth Elements by ICP OES After On-Line Enrichment Using Multi-Walled Carbon Nanotubes Coated Cellulose Acetate Membrane
This study investigates application of multi-walled carbon nanotubes coated cellulose acetate membrane for on-line extraction and preconcentration of some rare earth elements (Y, La, Ce, Nd, Sm, Gd and Dy) prior to their determination by inductively coupled plasma optical emission spectrometry. Sample solutions containing rare earth elements (pH: 6.0) and l-
J. Braz. Chem. Soc.. Publicado em: 2016-12
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12. Evaluation of Inductively Coupled Plasma Tandem Mass Spectrometry for Determination of As in Agricultural Inputs with High REE Contents
In the present work, an inductively coupled plasma-tandem mass spectrometer (ICP-MS/MS) operating in single quadrupole and mass shift modes were evaluated for As determination in mineral fertilizers and agricultural gypsum with high contents of rare earth elements. For MS/MS mode, oxygen was the gas introduced into the octopole reaction system (ORS3). Sample
J. Braz. Chem. Soc.. Publicado em: 2016-11