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Author Kang, Z. C. ♦ Eyring, L.
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword MATERIALS SCIENCE ♦ CERIUM OXIDES ♦ CHEMICAL PREPARATION ♦ ELECTRON MICROSCOPY ♦ COLLOIDS ♦ EXPERIMENTAL DATA ♦ GELS ♦ MEASURING METHODS ♦ RARE EARTH COMPOUNDS ♦ CERIUM COMPOUNDS ♦ CHALCOGENIDES ♦ DATA ♦ DISPERSIONS ♦ INFORMATION ♦ MICROSCOPY ♦ NUMERICAL DATA ♦ OXIDES ♦ OXYGEN COMPOUNDS ♦ SYNTHESIS ♦ Ceramics, Cermets, & Refractories- Preparation & Fabrication ♦ Ceramics, Cermets, & Refractories- Structure & Phase Studies
Abstract The steps in the evolution of colloidal gels during drying, aging, and crystallization into ceramic oxides are followed by high-resolution electron microscopy. Two systems are discussed in this paper. Colloidal ceric hydroxide gels in two morphologies were studied. In one, spherical gel particles with only short-range order were observed to dehydrate to polycrystalline CeO{sub 2} with large grain size. In the other a polycrystalline precipitate of CeO{sub 2} was observed to increase its order without altering its grain size. Colloidal terbium hydroxycarbonate is also observed to have short-range order even in the earliest stages. In contrast to the cerium oxide these disordered materials are observed to crystallize and decompose in dynamic stages (even revealing reversibilities) through the intermediate dioxymonocarbonate to the oxide as carbon dioxide and water are removed.
ISSN 00224596
Educational Use Research
Learning Resource Type Article
Publisher Date 1990-09-01
Publisher Place United States
Journal Journal of Solid State Chemistry
Volume Number 88
Issue Number 1


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