Distribution behavior of uranium, neptunium, rare-earth elements ( Y, La, Ce, Nd, Sm, Eu, Gd) and alkaline-earth metals (Sr,Ba) between molten LiClKCI eutectic salt and liquid cadmium or bismuth

In accordance with United Nations General Assembly resolution, the year 2019 was proclaimed the International Year of the Periodic Table of Chemical Elements. Rare-earth elements were discovered during the time of the Periodic System development. In the past few decades, their compounds have attracted great interest due to their unique reactivity. This review covers recent achievements in the field of intermolecular hydrophosphination of alkenes, dienes and alkynes, which is catalyzed by rare earth and alkaline-earth metal complexes. Catalytic hydrophosphination reaction is the addition of an P—H bond to С—С multiple bonds, and offers an efficient and elegant synthetic approach to production of the organophosphorus compounds widely used in industrial synthesis, pharmaceuticals, agrochemistry, and other areas. The high values of the ionic radii of rare earth and alkaline-earth metals in combination with the Lewis acidity provide their compounds with a pronounced tendency to complex formation and, accordingly, high coordination numbers. Due to high reactivity of M—E (E = C, H, N, P) bonds, ease of Ln—P ı-bond metathesis and multiple C—C bond insertions, these compounds offer new prospects for the catalysis of the alkenes and alkynes hydrophosphination. Therefore, complexes of non-toxic and relatively abundant in nature rare earth and alkaline earth metals can be a cheaper and more effective alternative to compounds of late transition metals in the catalysis of the C—P bond formation.

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Oxidation resistance and growth resistance of gray cast iron modified with alkaline-earth and rare-earth elements

Metal Science and Heat Treatment ◽

10.1007/bf00779888 ◽

1980 ◽

Vol 22 (4) ◽

pp. 297-298 ◽

Cited By ~ 2

Author(s):

I. N. Ganiev ◽

T. A. Li ◽

A. V. Vakhobov ◽

V. I. Asanov

Keyword(s):

Rare Earth ◽

Cast Iron ◽

Rare Earth Elements ◽

Oxidation Resistance ◽

Alkaline Earth ◽

Gray Cast Iron ◽

Gray Cast

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Immobilization of alkali, alkaline-earth and rare-earth elements by crystalline zirconium phosphate HZr2(PO4)3

Journal of the Ceramic Society of Japan ◽

10.2109/jcersj2.120.334 ◽

2012 ◽

Vol 120 (1404) ◽

pp. 334-337

Author(s):

Susumu NAKAYAMA

Keyword(s):

Rare Earth ◽

Rare Earth Elements ◽

Zirconium Phosphate ◽

Alkaline Earth

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Age and origin of Late Jurassic and Paleocene granitoids, Nelson Batholith, southern British Columbia

Canadian Journal of Earth Sciences ◽

10.1139/e93-200 ◽

1993 ◽

Vol 30 (12) ◽

pp. 2305-2314 ◽

Cited By ~ 16

Author(s):

J. H. Sevigny ◽

R. R. Parrish

Keyword(s):

British Columbia ◽

Rare Earth ◽

Rare Earth Elements ◽

Middle Jurassic ◽

Late Jurassic ◽

Alkaline Earth ◽

Biotite Granite ◽

Isotopic Data ◽

Quartz Monzonite ◽

Early Late

In the Middle Jurassic Nelson Batholith, southern British Columbia, young 40Ar/39Ar ages (i.e., 50–60 Ma) and distorted isobaric surfaces in the batholith suggest the possibility of Paleocene granitic plutonism. We present the results of a study undertaken to evaluate this possibility. Geochemical criteria successfully distinguish a suite of granitoids within the Nelson Batholith that differ from Nelson granites of similar SiO2 content. The granitoid suite is composed of 71.6–75.7 wt.% SiO2 leucocratic biotite granite and quartz monzonite with strong enrichments in alkaline, alkaline earth, and rare earth elements. Nd and Pb isotopic compositions suggest that biotite granite and quartz monzonite are not related. Biotite granite yields a U–Pb age of 158.9 ± 0.6 Ma (concordant zircons). Quartz monzonite crystallized at 61 ± 1 Ma, based on interpretation of titanite and zircon analyses. Zircons from this sample lie along a line from 61 to 160 Ma and demonstrate the presence of Middle Jurassic inheritance. Based on its petrographic and isotopic similarity to other Middle Jurassic plutons in the Nelson Batholith – Valhalla Complex area, we include the 159 Ma biotite granite with the Jurassic plutonic suite. This result demonstrates that magmatism in southern British Columbia was active at least until the early Late Jurassic (Oxfordian). The Paleocene (61 Ma) quartz monzonite that intrudes the southern Nelson Batholith is the structurally highest occurrence of "Ladybird" granite yet documented in southern British Columbia. Comparison of new and published geochemical and isotopic data for Paleocene granitoids throughout the southern Omineca Belt, British Columbia, suggests that these granitoids were not derived from a single, old crustal source.

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