Recent progress in impurity removal during rare earth …
As presented in Fig. 2, the Chinese controlled 97% of all rare earth oxide (REO) production in the world at the time and brought about a severe rare earth crisis for the rest of the. Methodology. The present review aims to systematically review recent progress in impurity removal during REE processing and to identify best practices for …
Radiolysis of LaF3 crystals with rare-earth impurities
PDF | The absorption spectra of LaF3 crystals, both pure and doped with rare-earth fluorides (YF3, CeF3, NdF3, PrF3, SmF3, EuF3, GdF3, TbF3, DyF3, HoF3,... | Find, read and cite all the research ...
Grain Boundary Strengthening in Alumina by Rare …
Grain Boundary Strengthening in Alumina by Rare Earth Impurities. J. Buban, K. Matsunaga, +4 authors. Y. Ikuhara. Published in Science 13 January 2006. …
Crystal field of rare earth impurities in LaF3
The method to calculate crystal field parameters was successfully applied to rare earth impurities in LaF 3, showing its applicability to R on sites with an arbitrary local symmetry. Despite the ionic character of the compound the R ( 4 f) - F ( 2 p, 2 s) hybridization plays a significant role.
Effects of Flue Gas Impurities on the Performance …
Selective catalytic reduction (SCR) is still the most widely used process for controlling NOx gas pollution. Specifically, commercial vanadium-based catalysts have problems such as narrow operating …
Skew scattering by rare-earth impurities in silver
It turns out that skew scattering by the rare-earth impurities contributes strongly to the Hall effect. The variation of the skew scattering in the rare-earth series allows us to separate what is due respectively to anisotropic terms of the k and of the k interactions. (a) a term p~ ~, of ordinary Hall resistivity which is due to the Lorentz force.
Determination of rare earth impurities in high purity …
Semantic Scholar extracted view of "Determination of rare earth impurities in high purity gadolinium oxide by inductively coupled plasma mass spectrometry after 2-ethylhexylhydrogen-ethylhexy phosphonate extraction chromatographic separation." by …
Determination of rare earth impurities in high purity …
A method was developed for the determination of rare earth impurities in high purity Gd 2 O 3 by inductively coupled plasma mass spectrometry (ICP-MS). The matrix suppression effect of Gd 2 O 3 on signals of rare earth impurities was compensated for by Re internal standardization. The spectra overlap interferences from GdH, GdO, …
Grain Boundary Strengthening in Alumina by Rare Earth Impurities
It is found that the yttrium segregates to very localized regions along the grain boundary and alters the local bonding environment, thereby strengthening the boundary against mechanical creep. Impurity doping often alters or improves the properties of materials. In alumina, grain boundaries play a key role in deformation mechanisms, …
Leaching and mass transfer characteristics of elements from …
The ion-adsorption type rare earth ore is an unconsolidated bed of clay minerals. Column leaching, heap leaching and in situ leaching are used in the industrial practice [].Nowadays, rare earth is recovered by in situ leaching process with (NH 4) 2 SO 4 solution in the industry and precipitated with ammonium bicarbonate. However, there …
ISO 23597:2023 (en), Rare earth ? Determination of rare earth …
In the products, there exist trace non-rare earth impurities including some carbonates, oxalates and moisture. Some of them (such as Ca, Si, Fe) come from raw materials and others (such as Fe) come from industrial processes of rare earth metal from the electrolytic process. ... Rare earth content refers to the mass fraction of all rare earth ...
Separation and Preconcentration of Impurities in …
Impurity elements noticeably affect the properties of materials based on rare earth elements (REEs). Therefore, sensitive, multielement, and reliable methods are …
Preparation of high-purity neodymium chloride by
Introduction. Neodymium (Nd) is an important element in astronavigation, clean energy and electronic industries. 1 With applications in these specialized areas increasing, high-purity Nd has been commonly required. For example, the product of Nd 2 O 3 applied in batteries and semiconductor laser requires that the content of RE (rare …
Recent progress in impurity removal during rare …
Impurities present in REE products greatly affect their properties and performance. •. Impurity removal processes must be developed to minimize entrainment. …
High temperature water vapour corrosion of rare earth disilicates …
The problems with impurities, particularly Ca in rare earth oxide powders, have been discussed above. Therefore all three diagrams may reflect a true situation: Fig. 6 a for the impurity laden system, Fig. 6 b for the Y- (Y/Yb-, Y/Lu-) system with Ca concentrations too small for the stabilisation of oxyapatite and Fig. 6 c for the Yb- and ...
Selective removal of impurities from rare earth sulphuric liquor …
This purification aims at reducing the concentration of impurities such as Fe 3+, Al 3+, PO 4 3− and UO 2 2+ in order to allow the production of marketable rare earth products, such as rare earth oxides or carbonates. Moreover, this purification is performed avoiding as much as possible any REEs losses, since this has a negative impact on the ...
ISO
The impurity elements to be analysed as typical non-rare earth impurities are the following five elements: Magnesium (Mg), Aluminum (Al), Silicon (Si), Calcium (Ca) and Iron (Fe). The specified measurement ranges for these impurities are shown in Table 1. An instrument capable of the achieving the below ranges is required for this …
(PDF) Influence of Impurities on the Properties …
Investigations of impurity centers, electrical resistivity and microstructure of BaTiO3 ceramics doped with rare-earth ions Y, La, Nd, Sm, Dy and Lu at concentrations x = 0.001–0.005 were ...
Damping by Slow Relaxing Rare Earth Impurities in
Damping by Slow Relaxing Rare Earth Impurities in Ni80 Fe20. G. Woltersdorf, M. Kiessling, G. Meyer, J.-U. Thiele, and C. H. Back. Phys. Rev. Lett. 102, 257602 – …
Direct Determination of Rare Earth Impurities in High …
irect etermination of Rare Earth Impurities in High-Purity Terbium Oxide with the NexION 1100 ICP-MS Figure 2. BEC of 10 µg/L Lu in 500 ppm Tb 4O 7 solution with different NH 3 gas flow. Figure 3. AFT optimization curve of 10 µg/L Lu in 500 ppm Tb4O 7 solution with RPq = 0.45 and NH 3 = 3 mL/min. An important cell parameter in the ...
Effective determination of trace rare earth elements in ThF
In order to analyze trace rare earth impurities in ThF 4, two effective analytical methods based on the matrix-matched strategy using ICP-MS with different sample pretreatment procedures are developed in this study.The first procedure involves the conversion of ThF 4 into ThO 2 by pyrohydrolysis and the subsequent dissolution of …
Research Progress in Preparation and Purification of …
Impurities such as Si, Fe, Al, Mo, Ti were mostly from rare earth oxide and reagent materials. Total concentration of impurities in rare earth metals could be …
Separation and Preconcentration of Impurities in Rare-Earth …
Besides rare earth impurities, an important role in the purity of REE-based materials is taken by non-rare-earth impurities (NREIs). For example, in the manufacture of phosphors and optical ceramics, high-purity rare earth oxides are used, and critical impurities are colored ions Fe, Ni, Cr, Co, Cu, V, Mn, etc., as well as some lanthanides [ …
Effect of Rare‐Earth Impurities on the Ferrimagnetic …
F. Hartmann‐Boutron; Effect of Rare‐Earth Impurities on the Ferrimagnetic Resonance and Nuclear Relaxation in Yttrium Iron Garnet. Journal of Applied Physics 1 March 1964; 35 (3): ... Then making the slow relaxation hypothesis, we rigorously calculate the susceptibilities of the rare‐earth ions and deduce that, in order to be successful ...
Rare-earth impurities in gallium nitride: The role of the …
Abstract. We performed a first principles investigation on the electronic properties of 4f-rare earth substitutional impurities in zincblende gallium nitride (GaN:REGa, with RE = Eu, Gd, Tb, Dy ...
Extraction and Separation of Rare Earth Elements …
It is worthwhile to note that, in this review, extraction of rare earth elements is construed to encompass processes or practices that dislodge or abstract REE's from …
Impact of Rare Earth (La, Pr, Eu) Impurities on the …
We report measurements of the magnetoresistance of gold containing rare-earth impurities in longitudinal and transverse magnetic fields. For rare-earths with orbital magnetism the dominant effect ...
Solid phase separation and ICP-OES/ICP-MS determination of rare earth …
Rare earth impurities in nuclear grade uranium oxide samples were determined by the well established extraction of uranium using TBP-TOPO-CCl 4. The advantage of this extraction is that it is a general method for determination of both REEs and common trace elements in a single go. However, this procedure suffers from draw back as TBP extractant ...
Radiolysis of LaF3 crystals with rare-earth impurities
The absorption spectra of LaF3 crystals, both pure and doped with rare-earth fluorides (YF3, CeF3, NdF3, PrF3, SmF3, EuF3, GdF3, TbF3, DyF3, HoF3, ErF3, TmF3, YbF3, and LuF3) have been investigated. All these impurities can be separated into two groups with respect to the shape of the absorption spectra of irradiated crystals. The …
Grain Boundary Strengthening in Alumina by Rare …
Impurity doping often alters or improves the properties of materials. In alumina, grain boundaries play a key role in deformation mechanisms, particularly in the phenomenon of grain boundary sliding during creep at high temperatures. We elucidated …