• The Korean Journal of Ceramics
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• v.4 no.2
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• pp.72-77
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• 1998

A defect model for UO$_2$ fuel containing soluble fission products was devised based on the defect structure of pure and doped uranias. Using the equilibrium between fuel solid-solution and fission-products and the material balance within the fuel, a tracing method to get the stoichiometry change of urania fuel with burnup was made. This tracing method was applied to high burnup urania fuel and DUPIC fuel. The oxygen potential of urania fuel turned out to increase slightly with burnup. The stoichiometry change was calculated to be negligible due to the buffering role f Mo. The oxygen potential of DUPIC fuel out to be sensitive to the initial chemical state of Mo in the fuel.

• Journal of English Language & Literature
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• v.57 no.5
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• pp.757-786
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• 2011

Seneca, the most influential classical Stoic and Justus Lipsius, the founder of Renaissance Stoicism suggest constancy, an unmovable strength of the steadfast mind based on reason and sound judgment, as a practical way or attitude in life full of both public and private evils. As a member of the Sidney family, Wroth is very much likely to have been influenced in molding her concept of constancy by Senecan and Lipsian Stoicism, which was introduced into England through Sir Philip Sidney's friendship with Lipsius. This paper explores Wroth's concept of constancy in Urania as a Stoic ideal in the context of the major Stoic writings of Seneca and Lipsius. While the titular character of the romance Urania shows some inherent attributes of Stoic constancy from the beginning of the romance, Pamphilia as the pattern of constancy gradually perfects the virtue through the ordeals of her love of Amphilanthus and her queenship. Her frequent retirements into private and secluded places are the essential occasions for her disciplining in Stoic constancy through self-examinations of her psychological and emotional disorders and poetry writing. Amphilanthus, a constantly inconstant lover, fully understands the importance of constancy in love as well in life only after his marriage to another woman and Pamphilia's marriage to another man. At the end of the romance they come to accept the vicissitudes of life in Stoic constancy. In Urania, Wroth transforms the strongly masculine Stoic constancy into a female heroic ideal. Thereby she presents those female characters as important political, ethical and cultural subjects and their constancy as a thread through the labyrinths of love and life.

• Nuclear Engineering and Technology
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• v.23 no.3
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• pp.321-327
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• 1991

A defect model e)[plaining the oxygen potential of Gadolinia doped urania based on the defect structure of pure urania has been developed. Gd-dopants are assumed to stay in the cation sites pushing away nearby oxygen interstitials reducing the number of interstitial sites. Gd-dopants also form dopant-vacancy clusters in the abundance of oxygen vacancies. This model explains the discontinuous change of the oxygen potential at O/M= as well as the increase of the potential with the dopant concentration.

• Analytical Science and Technology
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• v.20 no.2
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• pp.131-137
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• 2007

The urania-gadolinia fuels were dissolved with nitric acid. The analytical conditions of ICP-AES for the direct determinations of gadolinium in the uranium matrices without separation process were investigated. Based on the effect of uranium on gadolinium intensity, the best wavelength for gadolinium was 336.223 nm. The relative deviation of two methods, direct and indirect measurements with anion exchange chromatography, was less than 5 %. Therefore it was possible for this procedure directly to measure 5~10 wt.% of gadolinium in urania-gadolinia fuels without separation by ICP-AES.

• Proceedings of the Korean Nuclear Society Conference
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• 2001.05a
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• pp.273-273
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• 2001

• Proceedings of the Korean Nuclear Society Conference
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• 2001.10a
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• pp.220.2-220
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• 2001

• Proceedings of the Korean Nuclear Society Conference
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• 2002.10a
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• pp.270-270
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• 2002

• Journal of the Korean institute of surface engineering
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• v.36 no.1
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• pp.99-107
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• 2003

The diffusion coefficient of Xe-133 was obtained from an annealing test. The specimens were made from a UO$_2$ single crystal powder with natural enrichment. Weight and grain size were 300mg and ($23\mu\textrm{m}$, respectively. Oxygen potentials were obtained from an oxygen sensor. Released fractions were obtained from both results of gamma scans and quantitative analysis with MCNP code, The annealing test was performed at three temperatures at once. Diffusion coefficients of Xe-133 were calculated using slope of Booth theory in each O/M ratios. Activation energy and the pre-exponential factor of the diffusion coefficient were obtained. The activation energy of near stoichiomeric $UO_2$ is 310 kJ/mol. The measured values of near stoichiometric $UO_2$ are very close to other data available. Diffusion coefficients increase with hyper-stoichiometry, due to higher concentration of cation vacancies.