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Fig. 2 presents the effect of pressure on unit cell volume ratio in the zinc blend structure for ScN and YN semiconducting. We report in Table 1 the equilibrium structural parameters for scandium and yttrium nitrides calculated within LDA, GGA and HSE hybrid functional in the zinc blend structure. These parameters computed within HSE functional ...
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In the presence of Al, Fe and Mn, scandium was deposited from 6 M Н 2 SO 4 in the form of double sulfates of unidentified composition [Komissarova et al., 1965]. Based on different stability of scandium and yttrium group sulfates, K 3 Sc(SO 4) 3 can be crystallized with scandium selective precipitation efficiency of 98% [Volkov et al., 1997].
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Rare-earth metals, scandium, and yttrium 60 103 55 28 100 Consumption, apparent3 9,550 10,500 9,060 11,600 13,000 Price, dollars per kilogram, average:4 Cerium oxide, 99.5% minimum 3 2 2 2 2 Dysprosium oxide, 99.5% minimum 279 198 187 179 240 Europium oxide, 99.99% minimum 344 74 77 53 35 Lanthanum oxide, 99.5% minimum 3 …
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Mixtures of oxides of yttrium or scandium as the predominant metal 2846.90.2015 Free. Mixtures of chlorides of yttrium or scandium as the predominant metal 2846.90.2082 Free. Mixtures of other rare-earth carbonates, including scandium 2846.90.8075 3.7% ad val. Mixtures of other rare-earth compounds,
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15 hours agoAs the demand for rare earth elements increases world-wide, so too do the mining activities associated with rare earth element extraction. Rare earth elements are listed as 15 elements on the ...
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The outer or valence electrons for the 14 lanthanides and lanthanum are the same, 5d6s 2; for scandium, 3d4s 2; and for yttrium, 4d5s 2. There is some variation in the chemical properties of the lanthanides because of the lanthanide contraction and the hybridization, or mixing, of the 4 f electrons with the valence electrons.
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Provided by the Springer Nature SharedIt content-sharing initiative. Scandium and yttrium, like all other ions, complexes, or compounds, are toxic in excess. These and other elements of group IIIA are hard metals that bind weakly to organic ligands and may compete for the binding sites of some other elements.
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ionic radius, ion electronegativity, and the formal charge. Scandium, yttrium, as well as aluminum and the elements of the groups lA, IIA, the Ln and actinides, are classified in class A. These elements have different properties from those elements grouped in class B or …
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Scandium and yttrium are found in Norway as a silicate called 2SiO 2 •Y 2 O 3 •Sc 2 O 3 . Figure 6 shows the chemical composition of another ore found in Madagascar with a Sc content of 42.6%, which looks to be a complex silicate of scandium, zirconium, and aluminum . Sc can be recovered from the two kinds of thorveitite ores by …
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ABSTRACT Such physicochemical properties of sec-nonylphenoxy acetic acid (CA-100) as the solubility in water, acid dissociation constant in water, dimerization constant in heptane, and distribution constant in organic solvent-water were measured by two-phase titration. The extraction behaviors of scandium (III), yttrium (III), lanthanides …
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The crystal structures of the reduced yttrium and scandium chlorides (R x Cl y, R = Y, Sc, y: x < 2) are characterized by the edge-sharing R 6 octahedral layer-like (YCl and ScCl),...
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2 Scandium. Scandium Mineralogy. Minerals that contain Sc at concentrations greater than a few. ... Biochemistry of Scandium and Yttrium, Part 2: Biochemistry and Applications. Boston: Springer US ...
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Reochimica et Cosniochimica Acta, 1963, Vol. 27, pp. 577 to 622. Pergamon Press Ltd. Printed in Northern Ireland Abundances of the fourteen rare-earth elements, scandium, and yttrium in meteoritic and terrestrial matter* R. A. SCHMITT, R. H. SMITH, J. E. LASCH, A. W. MOSEN, D. A. OLEHY and J. VASILEVSKISI John Jay Hopkins Laboratory for Pure …
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Reversed-phase high-performance liquid chromatography with post-column derivatization using 4-(2-pyridylazo)-resorcinol (PAR) and UV–visible detection at 520 nm was tested to optimize separation and recovery, primarily for scandium but also for yttrium and the individual lanthanides, from iron present in the samples.
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It is found that scandium is extracted with 2,6-pyridinedicarboxylic acid diamides similarly to heavy lanthanides, while yttrium is extracted together with light group lanthanides. ... The four out of six studied ligands demonstrate significant potentiometric sensitivity towards scandium, yttrium and lanthanides in 10 −7 –10 −3 mol/L ...
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Although the first 3d metal, scandium is not a transition metal, but has significantly different properties, partly on account of its slightly greater size, forming complexes with higher coordination numbers (e.g. the aqua ion [Sc(H 2 O) 7] 3+). Its …
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ScCl 3 reacts with 2 equiv of KC 5 Me 4 H to form (C 5 Me 4 H) 2 ScCl(THF), 1, which reacts with allylmagnesium chloride to make (C 5 Me 4 H) 2 Sc(η 3-C 3 H 5), 2. Complex 2 reacts with [HNEt 3 ][BPh 4 ] to yield [(C 5 Me 4 H) 2 Sc][(μ-Ph)BPh 3 ], 3, which has just one primary Sc−C(phenyl) contact connecting the tetraphenylborate anion and ...
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1972). The electron binding energies and the electronic structures of scandium and yttrium are presented in Table 2-2 and Figs. 2-1 and 2-2, respectively. 2.3 General Chemical and Physical Properties Scandium shows few similarities with other d …
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Authors and Affiliations. Environmental Chemistry & Ecotoxicology, University of Gdańsk, 63 Wita Stwosza Str., 80‑308, Gdańsk, PL, Poland. Małgorzata Mędyk
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It was called an' earth' because it was yttrium oxide, Y 2 O 3, ... 20 years ago, most scientists had not heard of it, other than vaguely noting where it was in the periodic table, under scandium and above lanthanum. Some people might just have known that it was one of 4 chemical elements named after the small Swedish town of Ytterby, along ...
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Scandium, atomic number 21. It is the first of the transition metals, and its discovery is entwined with that of vertical neighbours yttrium and lanthanum. The Swedish island of Resarö, near Stockholm, became a hotbed of elemental discovery in the late eighteenth, …
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Scandium is found in most rare earth element deposits and is sometimes classified as a rare earth element. The International Union of Pure and Applied Chemistry includes scandium in their rare earth element definition. ... The most abundant rare earth elements are cerium, yttrium, lanthanum and neodymium [2]. They have average crustal ...
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Thus, scandium, yttrium and lutetium all have a coordination number of 6 in their oxides M 2 O 3 (M = Sc, Y, Lu) and in all the halides, save the fluoride. Apart from the fluoride (six coordinate WO 3 structure), all ScX 3 (X = F, Cl, Br, I) have the FeCl 3 structure, also adopted by LuX 3 (X = Br, I) whilst LuCl 3 has the AlCl 3 structure.
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Scandium is a metal that has many of the characteristics of the rare earth elements, particularly yttrium. It is a light material with a higher melting point than aluminum, giving it uses in aerospace and other …
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Abstract. The members of the Sc Group are Sc scandium, Y yttrium, La lanthanum, Ce cerium, Pr praseodymium, Nd neodymium, Pm promethium, Sm samarium, Eu europium, Gd gadolinium, Tb terbium, Dy dysprosium, Ho holmium, Er erbium, Tm thulium, Yb ytterbium, Lu lutetium, and Ac actinium. All these elements resemble each other greatly, …
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A process of removing impurities, such as Fe, Zr, Ti, Al, Si, from scandium solution by ion exchange was proposed. Various resins' selectivity was studied in scandium chloride solution. The results indicated that D851 resin had high selectivity of Sc at low acidity, and high selectivity of Zr at high acidity; D370 resin had high selectivity of Fe and …
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Synthesis and structure of double-metal-layered scandium, yttrium, and zirconium chloride carbides and nitrides, M2Cl2C and M2Cl2N | Inorganic Chemistry. ACS Publications. C&EN. Authors & Reviewers. Website Demos & Tutorials. For Librarians & Account Managers. …
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Rare Earths. The rare earths, or rare earth elements (REE), are a relatively abundant group of elements consisting of scandium, yttrium, and the 15 elements of the lanthanide series of the periodic table. Scandium (Sc) is the lightest rare earth element. Scandium is present in crustal rocks in amounts greater than lead and precious metals, but ...
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Much important uranium chemistry is reported, often of great interest. Notable is the work of Ephritikhine and co-workers, especially comparing lanthanide and actinide compounds of the same ligand, and highlights from Andersen's group include the molecular [(η 5-1,2,4-(Bu t) 3 C 5 H 2) 2 U = O]. The outstanding work, both in quality and quantity, has come from …
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Japan is the world's leading importing country of scandium and yttrium. In 2020, Japan imported nearly 6,800 metric tons of the rare earth-metals, with a value of approximately 201.7 million U.S ...
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