Zirconia – A Ceramic for Excess weapons Plutonium Wastes

1999 ◽  
Vol 556 ◽  
Author(s):  
W. L. Gong ◽  
W. Lutze ◽  
R. C. Ewing
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Metal Oxides ◽  
Solid Solutions ◽  
Binary Systems ◽  
Single Phase ◽  
Sol Gel ◽  
Neutron Absorber ◽  
Cubic Zirconia

AbstractWe synthesized a ceramic containing simulated excess weapons plutonium waste in solidsolution with zirconia (ZrO2)ss. ZrO2 has a large solubility for other metal oxides. More thantwenty binary systems AxOy- ZrO2 have been reported in the literature, including PuG2, rare earth elements, and oxides of metals contained in weapons plutonium wastes. We show that significant amounts of gadolinium (neutron absorber) and yttrium (stabilizer of the cubic modification) can be dissolved in ZrO2, together with plutonium (simulated by Th4+, Ce4+, or U4+) and impurities (e.g., Ca Mg, Fe, Si). Sol-gel and powder methods were applied to make homogeneous, single phase zirconia solid solutions. Pu waste impurities were completely dissolved in the solid solutions. In contrast to other phases, e.g., zirconolite and pyrochlore, yttrium stabilized cubic zirconia does not undergo amorphization upon irradiation.

Uptake of rare earth elements from solution by metal oxides

1993 ◽  
Vol 27 (9) ◽  
pp. 1796-1802 ◽  
Author(s):  
Dirk Koeppenkastrop ◽  
Eric H. De Carlo
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Metal Oxides

Sol-Gel synthesis of an optical silica glass doped with rare-earth elements

2007 ◽  
Vol 33 (2) ◽  
pp. 152-155 ◽  
Author(s):  
N. N. Khimich ◽  
G. M. Berdichevskii ◽  
E. N. Poddenezhnyi ◽  
V. V. Golubkov ◽  
A. A. Boiko ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Silica Glass ◽  
Sol Gel ◽  
Sol Gel Synthesis

scholarly journals The Synthesis and Characterization of Sol-Gel-Derived SrTiO3-BiMnO3 Solid Solutions

Crystals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1125
Author(s):  
Dovydas Karoblis ◽  
Ramunas Diliautas ◽  
Eva Raudonyte-Svirbutaviciene ◽  
Kestutis Mazeika ◽  
Dalis Baltrunas ◽  
...  
Keyword(s):  
Solid Solutions ◽  
Single Phase ◽  
Perovskite Phase ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Paramagnetic Materials ◽  
Ft Ir ◽  
Ir Analysis ◽  
Superposition Effect

In this study, the aqueous sol-gel method was employed for the synthesis of (1−x)SrTiO3-xBiMnO3 solid solutions. Powder X-ray diffraction analysis confirmed the formation of single-phase perovskites with a cubic structure up to x = 0.3. A further increase of the BiMnO3 content led to the formation of a negligible amount of neighboring Mn3O4 impurity, along with the major perovskite phase. Infrared (FT-IR) analysis of the synthesized specimens showed gradual spectral change associated with the superposition effect of Mn-O and Ti-O bond lengths. By introducing BiMnO3 into the SrTiO3 crystal structure, the size of the grains increased drastically, which was confirmed by means of scanning electron microscopy. Magnetization studies revealed that all solid solutions containing the BiMnO3 component can be characterized as paramagnetic materials. It was observed that magnetization values clearly correlate with the chemical composition of powders, and the gradual increase of the BiMnO3 content resulted in noticeably higher magnetization values.

Structures and Optical Properties of Nanoforest-Like Carbon Nanotubes Decorated with Nanoparticles of Strontium Aluminate Doped with Rare-Earth Elements

MRS Advances ◽  
2018 ◽  
Vol 3 (1-2) ◽  
pp. 121-126
Author(s):  
Patsy Y. Arquieta Guillén ◽  
Alena Borisovna Kharissova ◽  
Beatriz Ortega García ◽  
Oxana V. Kharissova
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Rare Earth ◽  
Rare Earth Elements ◽  
Metal Oxides ◽  
Spray Pyrolysis ◽  
Metal Oxide Nanoparticles ◽  
Strontium Aluminate ◽  
Fluorescent Properties ◽  
Multi Wall Carbon Nanotubes

ABSTRACTNowadays, carbon nanotubes have a lot of applications in daily life, being applied in the fabrication of cellphones, computers, nanotransistors, among many others. Currently, their new applications in biotechnology area are in research, in particular in order to find new biosensors with fluorescent properties applying on the basis of multi-wall carbon nanotubes (MWCNTs). In this work, the obtaining of carbon nanoparticles having fluorescent properties via spray pyrolysis is presented. Synthesis, properties, structural peculiarities, and applications of nanobuds and related nanostructures are discussed. MWCNTs, decorated with strontium aluminate SrAl12O19 and doped with rare-earth elements, were synthetized from distinct organic precursors and the corresponding metal oxides. The metal oxides used were Samarium (Sm), Europium (Eu), Neodymium (Nd), Lanthanum (La), Cerium (Ce) and some their combinations.The synthesis was carried out on the surface of optical fibres to obtain a uniform growth of forest-like MWCNTs, adding to metal oxide nanoparticles to their surface. The preparation of composites was carried out by spray pyrolysis techniques in dry nitrogen atmosphere in the temperature range from 780 to 850°C. The formed products were characterized by Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), FTIR spectroscopy, Raman spectroscopy and UV/visible spectroscopies. The analysis of the obtained data shows that the deposited nanoparticles are in the range of size 20-60 nm being uniformly distributed on the surface of MWCNTs. The samples, obtained at different temperatures and with doping metal oxides added to SrAl12O19, show different fluorescence behavior. The best results were observed with lanthanum oxide as a dopant. Possible applications as persistently luminescent phosphors for the formed MWCNTs-supported luminescent materials are proposed.

The Mutual Solubility of Salts of Rare Earth Elements

2015 ◽  
Vol 670 ◽  
pp. 82-88
Author(s):  
Vera A. Batyreva ◽  
Larisa S. Grigor’eva
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Solid Solutions ◽  
Mutual Solubility ◽  
Pure Form ◽  
High Tech

Relevance of the work caused by necessity of expanding the database of the mutual solubility of salts of rare earth elements to create technologies for producing them in pure form for high-tech industries. The main aim of the study: was to investigate reciprocal solubility of lanthanum and erbium bromates and trichloroacetates in the water and the and to determine the conditions of solid solutions formation and the possibility of obtaining concentrates of lanthanum and erbium.

scholarly journals Compositional Variability of Monazite–Cheralite–Huttonite Solid Solutions, Xenotime, and Uraninite in Geochemically Distinct Granites with Special Emphasis to the Strongly Fractionated Peraluminous Li–F–P-Rich Podlesí Granite System (Erzgebirge/Krušné Hory Mts., Central Europe)

Minerals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 127
Author(s):  
Karel Breiter ◽  
Hans-Jürgen Förster
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Solid Solutions ◽  
Heavy Rare Earth Elements ◽  
Compositional Variability ◽  
Variscan Granites ◽  
Almost All ◽  
Ree Pattern ◽  
Highly Evolved ◽  
Comprehensive Study

A comprehensive study of monazite–cheralite–huttonite solid solutions (s.s.) and xenotime from the highly evolved, strongly peraluminous P–F–Li-rich Podlesí granite stock in the Krušné Hory Mts., Czech Republic, indicates that, with the increasing degree of magmatic and high-T early post-magmatic evolution, the content of the cheralite component in monazite increases and the relative dominance of middle rare earth elements (MREE) in xenotime becomes larger. Considering the overall compositional signatures of these two accessory minerals in the late Variscan granites of the Erzgebirge/Krušné Hory Mts., three types of granites can be distinguished: (i) chemically less evolved F-poor S(I)- and A-type granites contain monazite with a smooth, mostly symmetric chondrite-normalized (CN) rare-earth elements (REE) pattern gradually declining from La to Gd; associated xenotime is Y-rich (˃0.8 apfu Y) with a flat MREE–HREE (heavy rare earth elements) pattern; (ii) fractionated A-type granites typically contain La-depleted monazite with Th accommodated as the huttonite component, combined with usually Y-poor (0.4–0.6 apfu Y) xenotime characterized by a smoothly inclining, Yb–Lu-dominant CN-REE pattern; (iii) fractionated peraluminous Li-mica granites host monazite with a flat, asymmetric (kinked at La and Nd) CN-LREE pattern, with associated xenotime distinctly MREE (Gd–Tb–Dy)-dominant. Monazite and xenotime account for the bulk of the REE budgets in all types of granite. In peraluminous S(I)-type granites, which do not bear thorite, almost all Th is accommodated in monazite–cheralite s.s. In contrast, Th budgets in A-type granites are accounted for by monazite–huttonite s.s. together with thorite. The largest portion of U is accommodated in uraninite, if present.

The effects of the modification of the BST-system solid solutions with rare earth elements

2021 ◽  
Author(s):  
K.P. Andryushin ◽  
L.A. Shilkina ◽  
S.V. Khasbulatov ◽  
A.V. Nagaenko ◽  
S.I. Dudkina ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Solid Solutions
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