• Bulletin of the Korean Chemical Society
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• v.21 no.6
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• pp.567-570
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• 2000

Bovine liver catalase was exposed to cysteine, as a natural inactivator metabolize, causing autoxidation-generating $H_2O_2$ continuously. The catalase species concentrations and activity measurement were done by spectrophotometry in phosphate buffer 10mM, pH 6.5, and 27 $^{\circ}C$. The activity of catalase decreased continuously due to the conversion of active ferricatalase species, E-Fe (III), to an inactive enzyme species, E-Fe (IV). This conversion is related to the slow production of $H_2O_2generated$ by autoxidation of cysteine. The free SH-group of cysteine has an essential role in production of $H_2O_2$ and hence inactivation of catalase. NADPH can protect catalase against inactivation due to the conversion of inactive form of E-Fe (IV) to ferricatalase species, E-Fe (III).

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.12 no.1
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• pp.31-35
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• 2002

Abstract Spinel powder having a particle size of 0.9$\mu$m was calcined for 30 min at $1300^{\circ}C$, followed by ball milling for 4h, to obtain the spinel particle size of 3.29$\mu$m. The die-pressed spinel was presintered at $1100^{\circ}C$ for 2h and then lanthanum aluminosilicate glass was infiltrated at $1080^{\circ}C$ for 0~2 h to investigate the penetration kinetics in glass-spinel composite. The infiltration distance is parabolic in time due to capillarity. The strength and the fracture toughness of glassspinel composites were 317 MPa and 3.56 MPa $m^{1/2}$ respectively and dual microstructure of column (needle) and polygonal shapes as a result of recrystallization was observed due to the high calcination temperature.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.373-378
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• 2003

As a part of assessment of the structural material for the molten salt handling system, corrosion behavior of austenitic alloys, Fe-base and Ni-base in the molten salt of $LiCl-Li_2O_2$ was investigated in the range of temperature; 650~$725^{\circ}C$, time; 24- 168h, $Li_2O$; 3wt%, mixed gas; Ar-10%$O_2$. In the molten salt of $LiCl-Li_2O_2$, Ni-base alloys showed higher corrosion resistance than Fe-base alloys. Fe-base alloy with low Fe and high Ni contents exhibited better corrosion resistance. The scales of $Cr_2O_3$, $FeCr_2O_4$ on Fe-base alloys were showed, and $Cr_2O_3$, $NiFe_2O_4$ on Ni-base alloys were also showed.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2003.11a
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• pp.25-28
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• 2003

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2000.11a
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• pp.18-18
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• 2000

• Proceedings of the Materials Research Society of Korea Conference
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• 2001.05a
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• pp.89-89
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• 2001

• Proceedings of the KSEEG Conference
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• 2007.04a
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• pp.370-372
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• 2007

• Proceedings of the Korean Ceranic Society Conference
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• 2003.10a
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• pp.219.1-219
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• 2003

• Bulletin of the Korean Chemical Society
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• v.7 no.4
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• pp.318-320
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• 1986

• Korean Journal of Metals and Materials
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• v.50 no.3
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• pp.218-223
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• 2012

Fe-(8.5, 18.5, 28.3, 36.9) wt% Cr alloys were corroded between 600 and $800^{\circ}C$ for up to 70 h in a 1 atm gas mixture that consisted of 0.0242 atm of $H_2S$, 0.031 atm of water vapor, and 0.9448 atm of nitrogen gas. Their corrosion resistance increased with an increment in the Cr content. The Fe-8.5%Cr alloy corroded fast, forming thick, fragile, nonadherent scales that consisted primarily of an outer FeS layer and an inner (Fe, Cr, O, S)-mixed layer. The outer FeS layer grew into the air by the outward diffusion of $Fe^{2+}$ ions, whereas the inner mixed layer grew by the inward diffusion of oxygen and sulfur ions. At the interface of the outer and inner scales, voids developed and cracking occurred. The Fe-(18.5, 28.3, 36.9)% Cr alloys displayed much better corrosion resistance than the Fe-8.5Cr alloy, because thin $Cr_2O_3$ or $Cr_2S_3$ scales formed.