Imperial College London
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ProfessorRobinGrimes

Faculty of Engineering, Department of Materials

BCH Steele Chair in Energy Materials
 
 
 
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Contact

 

+44 (0)20 7594 6730r.grimes

 
 
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Location

 

B303cBessemer BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Pavlov:2017:10.1016/j.actamat.2017.07.060,
author = {Pavlov, TR and Wenman, MR and Vlahovic, L and Robba, D and Konings, RJM and Van, Uffelen P and Grimes, RW},
doi = {10.1016/j.actamat.2017.07.060},
journal = {Acta Materialia},
pages = {138--154},
title = {Measurement and interpretation of the thermo-physical properties of UO2 at high temperatures: the viral effect of oxygen defects},
url = {http://dx.doi.org/10.1016/j.actamat.2017.07.060},
volume = {139},
year = {2017}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Values are reported of specific heat, thermal conductivity and thermal diffusivity of UO2 from 1500 K to 2900 K based on laser flash measurements. Experiment is complemented by the development of solid state physics models that aid in the interpretation of the results. Specific heat is shown to exhibit a smooth maximum at 2715 K ± 100 K, consistent with a competition between two processes - oxygen defect interactions (net attraction) and saturation of oxygen interstitial sites. The specific heat model and measurements show, for the first time that a gradual pre-melting transition is consistent with high temperature literature values – enthalpy increment measurements and independently measured high temperature oxygen defect concentrations. Thermal conductivity exhibits a minimum consistent with: 1) an increase in electronic thermal conductivity via polaron production and mobilization and 2) degradation in lattice thermal conductivity due to phonon - phonon scattering and phonon - defect scattering. It is predicted that the high concentration of oxygen defects should contribute significantly to electrical conductivity and thermal expansion at high temperatures.
AU  - Pavlov,TR
AU  - Wenman,MR
AU  - Vlahovic,L
AU  - Robba,D
AU  - Konings,RJM
AU  - Van,Uffelen P
AU  - Grimes,RW
DO  - 10.1016/j.actamat.2017.07.060
EP  - 154
PY  - 2017///
SN  - 1359-6454
SP  - 138
TI  - Measurement and interpretation of the thermo-physical properties of UO2 at high temperatures: the viral effect of oxygen defects
T2  - Acta Materialia
UR  - http://dx.doi.org/10.1016/j.actamat.2017.07.060
UR  - https://www.sciencedirect.com/science/article/pii/S1359645417306419
UR  - http://hdl.handle.net/10044/1/53520
VL  - 139
ER  -
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