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Title: Phase evolution studies in CaZrTi{sub 2}O{sub 7}−RE{sub 2}Ti{sub 2}O{sub 7} (RE = Nd{sup 3+}, Sm{sup 3+}) system: Futuristic ceramic host matrices for nuclear waste immobilization

Abstract

Series of compositions with general stoichiometry as Ca{sub 1−x}Zr{sub 1−x}RE{sub 2x}Ti{sub 2}O{sub 7} (RE = Nd{sup 3+}, Sm{sup 3+}) were prepared by solid state reaction and characterized by powder x-ray diffraction technique to unravel the phase fields in the title systems. The phase fields in CaZrTi{sub 2}O{sub 7−}Nd{sub 2}Ti{sub 2}O{sub 7} and CaZrTi{sub 2}O{sub 7−}Sm{sub 2}Ti{sub 2}O{sub 7} systems differed significantly at the rareearth rich regions. The common phase fields like zirconolite-2M, zirconolite-4M, cubic perovskite are observed at the zirconolite rich regions of both systems. Depending on the structure of RE{sub 2}Ti{sub 2}O{sub 7} phase, the cubic pyrochlore or monoclinic RE{sub 2}Ti{sub 2}O{sub 7} phases are observed in the studied system. The observed phase fields in these two systems indicate ionic radius of the rare-earth ion has a dominating role in the phase relations. Further details of the phases and their homogeneity are explained in the text of the manuscript.

Authors:
; ;  [1]
  1. Chemistry Division, Bhabha Atomic Research Centre, Mumbai-400085 (India)
Publication Date:
OSTI Identifier:
22269511
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1591; Journal Issue: 1; Conference: 58. DAE solid state physics symposium 2013, Patiala, Punjab (India), 17-21 Dec 2013; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 12 MANAGEMENT OF RADIOACTIVE WASTES, AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES; CALCIUM COMPOUNDS; CERAMICS; CUBIC LATTICES; ENCAPSULATION; MONOCLINIC LATTICES; PHASE STABILITY; PHASE STUDIES; POWDERS; RADIOACTIVE WASTE PROCESSING; SAMARIUM IONS; TITANATES; X-RAY DIFFRACTION; ZIRCONOLITE

Citation Formats

Jafar, M., E-mail: sachary@barc.gov.in, Achary, S. N., E-mail: sachary@barc.gov.in, and Tyagi, A. K., E-mail: sachary@barc.gov.in. Phase evolution studies in CaZrTi{sub 2}O{sub 7}−RE{sub 2}Ti{sub 2}O{sub 7} (RE = Nd{sup 3+}, Sm{sup 3+}) system: Futuristic ceramic host matrices for nuclear waste immobilization. United States: N. p., 2014. Web. doi:10.1063/1.4872488.
Jafar, M., E-mail: sachary@barc.gov.in, Achary, S. N., E-mail: sachary@barc.gov.in, & Tyagi, A. K., E-mail: sachary@barc.gov.in. Phase evolution studies in CaZrTi{sub 2}O{sub 7}−RE{sub 2}Ti{sub 2}O{sub 7} (RE = Nd{sup 3+}, Sm{sup 3+}) system: Futuristic ceramic host matrices for nuclear waste immobilization. United States. doi:10.1063/1.4872488.
Jafar, M., E-mail: sachary@barc.gov.in, Achary, S. N., E-mail: sachary@barc.gov.in, and Tyagi, A. K., E-mail: sachary@barc.gov.in. 2014. "Phase evolution studies in CaZrTi{sub 2}O{sub 7}−RE{sub 2}Ti{sub 2}O{sub 7} (RE = Nd{sup 3+}, Sm{sup 3+}) system: Futuristic ceramic host matrices for nuclear waste immobilization". United States. doi:10.1063/1.4872488.
@article{osti_22269511,
title = {Phase evolution studies in CaZrTi{sub 2}O{sub 7}−RE{sub 2}Ti{sub 2}O{sub 7} (RE = Nd{sup 3+}, Sm{sup 3+}) system: Futuristic ceramic host matrices for nuclear waste immobilization},
author = {Jafar, M., E-mail: sachary@barc.gov.in and Achary, S. N., E-mail: sachary@barc.gov.in and Tyagi, A. K., E-mail: sachary@barc.gov.in},
abstractNote = {Series of compositions with general stoichiometry as Ca{sub 1−x}Zr{sub 1−x}RE{sub 2x}Ti{sub 2}O{sub 7} (RE = Nd{sup 3+}, Sm{sup 3+}) were prepared by solid state reaction and characterized by powder x-ray diffraction technique to unravel the phase fields in the title systems. The phase fields in CaZrTi{sub 2}O{sub 7−}Nd{sub 2}Ti{sub 2}O{sub 7} and CaZrTi{sub 2}O{sub 7−}Sm{sub 2}Ti{sub 2}O{sub 7} systems differed significantly at the rareearth rich regions. The common phase fields like zirconolite-2M, zirconolite-4M, cubic perovskite are observed at the zirconolite rich regions of both systems. Depending on the structure of RE{sub 2}Ti{sub 2}O{sub 7} phase, the cubic pyrochlore or monoclinic RE{sub 2}Ti{sub 2}O{sub 7} phases are observed in the studied system. The observed phase fields in these two systems indicate ionic radius of the rare-earth ion has a dominating role in the phase relations. Further details of the phases and their homogeneity are explained in the text of the manuscript.},
doi = {10.1063/1.4872488},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1591,
place = {United States},
year = 2014,
month = 4
}
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