• Proceedings of the Korean Nuclear Society Conference
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• 1997.05b
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• pp.217-222
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• 1997

핵연료 물질인 금속 우라늄과 이산화 우라늄의 플라즈마 기체에 의한 에칭 연구가 수행되었다. 연구에 사용된 플라즈마 기제는 CF$_4$와O$_2$의 혼합기체이며 CF$_4$/O$_2$의 혼합비. 시편 표면의 온도, R.F power, 그리고 압력에 따른 에칭율을 측정하였다. L-metal의 경우는 R.F power를 50W로 고정하고 아주 낮은 $O_2$의 성분비와 반응시간에 따른 에칭정도를 질량결손으로 계산하였다. $UO_2$의 에칭에 있어서는 CF$_4$/O$_2$의 비가 4:1에서 가장 높은 에칭율을 보였으며 그 에칭율은 최대 1000 monolayers/min 이었으며 U-metal의 경우 그 에칭율은 $UO_2$와 비교하여 10배 가량 낮은 것으로 나타났다.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2007.05a
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• pp.153-154
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• 2007

• Proceedings of the Materials Research Society of Korea Conference
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• 2000.11a
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• pp.76-76
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• 2000

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2001.05a
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• pp.551-553
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• 2001

• Journal of environmental and Sanitary engineering
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• v.15 no.1
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• pp.25-33
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• 2000

The new ion exchange resin was synthesized from chloromethylated styrene-1,4-divinylbenzene(DVB) with 1-aza-15-crown-5 macrocyclic ligand by substitution reaction. The effect of pH, time, dielectric constant of solvent and cross-linked of the matrix on the adsorption for $UO_2^{2+}$, $Ca^{2}$ and $Lu^{3+}$ was investigated. The metal ion was not adsorbed on the resins below pH 3 but above pH 4 fast adsorption behavior was showed. The optimum equilibrium time for adsorption of metallic ions was two hours. The adsorption selectivity determined in ethanol matrix was in increasing order $UO_2^{2+}>Ca^{2}>Lu^{3+}$. The adsorption power was in the order of 1%, 2%, 10% and 20% -crosslinked resin, but adsorption properties of resins decreased in proportion to the order of dielectric constant of solvents used. In addition, these metal ions could be separated in the column packed with 1% crosslinked resin by pH2.5 $HNO_3$ as an eluent.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.119-119
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• 2003

탄화규소나 열분해 탄소는 고온 특성 및 화학적인 안정성 이 우수하여 단미 혹은 코팅재로로 소재의 성능을 향상시키기 위하여 에너지 관련 분야, 반도체 치구 분야, 방위산업 및 항공우주 분야와 원자력 분야에서 다양하게 사용된다. 특히 원자력 분야에서는 고온형 원자로의 노심 요소 부품으로 적용 및 개발을 고려하고 있으며, 대표적인 예로 수소생산용 초고온 가스냉각로의 코팅 핵연료 입자를 들 수 있다. 일반적으로 TRISO라 불리는 가스냉각로 핵연료는 구형 $UO_2$ kemel의 주변을 PyC-SiC -PyC의 삼중 코팅층으로 둘러싸는 구조를 하고 있으며, 이 코팅층들은 kernel물질이 분열하는 동안 발생되는 내부 기체 압력을 견디는 압력용기 역할과 기체나 금속 핵분열 생성물들을 가두는 확산 장벽 역할을 하게 된다. 본 연구에서는 구형의 $UO_2$대신 선행연구를 위하여 구형 ZrO$_2$를 이용하여 증착온도나 시간 및 입력기체비 등의 화학증착 변수로 조절하여 SiC 및 PyC을 코팅하고, 각 변수들에 의한 증착층의 거동을 고찰하고자 하였다.

• Bulletin of the Korean Chemical Society
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• v.6 no.4
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• pp.225-228
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• 1985

The absorptions of Fe(Ⅲ), Tb(Ⅲ), Tl(Ⅰ), Ce(Ⅲ), Th(Ⅳ), and $UO_2^{2+}$ ions into the Dowex 50W-X2, 100-200 mesh resin were investigated by spectrophotometry to understand the abnormal strong absorption behavior of cations to cation exchange resins in concentrated HClO4. The distribution coefficients increase in the order : Tl(Ⅰ) < Fe(Ⅲ) < Tb(Ⅲ)∼Ce(Ⅲ) < $UO_2^{2+}$< Th(Ⅳ) and the order is interpreted in terms of the ratio of charge-to-ionic radius. The mole ratios of increment of $ClO_4^-$ ion absorption to metal ion absorption showed the same order as the distribution coefficients, which indicates that the electrostatic association between $ClO_4^-$ ion and metal ion plays a major role in the strong absorption.

• Journal of the Korean Chemical Society
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• v.55 no.3
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• pp.412-417
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• 2011

A series of homobinuclear complexes of the type [$M_2L(NO_3)_n(H_2O)_m$] where M=$UO_2$(VI), ZrO(IV), Th(IV); L=3-benzylidine-imino-5-p-sulphonamido phenyl azo-2-thiohyatoin(bispt), 3-furfurylidine-imino-5-p-sulphonamido phenyl azo-2-thiohydantoin(fispt),3-pyridyl-2'-methylene-imino-5-p-sulphonamido phenyl azo-2-thiohydantoin(pmispt) and 3-thienyl-2'-methylene-imino-5-p-sulphoanamido phenyl azo-2-thiohydantoin(tmispt); n=8 for Th(IV) and 4 for others, m=4 for bispt and 3 for others have been synthesized and characterized on the basis of elemental analysis, thermal analysis, molar conductance, magnetic moment and spectroscopic data (IR, electronic and $^1H$-NMR). In the light of this information, the ligands can be visualized as tetradentate co-ordinating through azomethine nitrogen, carbonyl oxygen to one metal centre where as azo nitrogen and thioimido nitrogen to the other metal centre yielding homo binuclear complexes of the above composition. The fungi toxicity of the ligands & their zirconyl complexes against some fungal pathogen has been studied.

• Nuclear Engineering and Technology
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• v.41 no.2
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• pp.155-162
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• 2009

Since the 90's, EDF and AREVA-NP have irradiated, up to very high burnups, lead assemblies housing $M5^{(R)}$ cladded fuels. Post-irradiation examination of high burnup $UO_2$ pellets show an increase in the fission-gas release rate, an increase in fuel swelling, and formation of fission-gas bubbles throughout the pellets. Xenon abundances were quantified, and phenomena leading to this bubble formation were identified. All examinations provided valuable data on the complex state of the fuel during irradiation. They show the good behavior of these fuels, exhibiting various microstructures at very high burnups, none of which is likely to lead to problems during irradiation.

• Journal of environmental and Sanitary engineering
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• v.14 no.3
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• pp.80-89
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• 1999

The ion exchange resins have been synthesized from chlormethyl styrene-1,4-divinyl benzene(DVB) with 1%, 5%, and 10%-crosslinking and macrocyclic ligand of cryptand type by copolymerization method and the adsorption characteristics of uranium(VI), lead(II) and holmium(III) ions have been investigated in various experimental conditions. The correlation between the adsorption characteristics of rare earths and transition metal on the resins and stability constants of complexes with macrocyclic ligand have been examined. The $UO_2^{2+}$ aqueous solutions are not adsorbed on the resins below pH 3.0, but the power of adsorption of $UO_2^{2+}$ increased rapidly above pH 4.0. The adsorption power was in the order of 1%, 10%, and 5%-crosslinked resin, but adsorptive characteristics of resins decreased in proportion to the order of dielectric constants of solvents.