• 한국광학회:학술대회논문집
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• 한국광학회 2005년도 하계학술발표회
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• pp.46-47
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• 2005

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2001년도 춘계학술발표회요약집
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• pp.270.1-270
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• 2001

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2001년도 추계학술발표회요약집
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• pp.281.1-281
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• 2001

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1999년도 추계학술발표회요약집
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• pp.299.2-299
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• 1999

• Asian Pacific Journal of Cancer Prevention
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• 제16권6호
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• pp.2251-2256
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• 2015

To study effects of cellular FLICE (FADD-like IL-$1{\beta}$-converting enzyme)-inhibitory protein (c-FLIP) inhibition by RNA interference (RNAi) on sensitivity of U2OS cells to tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL)-induced apoptosis, plasmid pSUPER-c-FLIP-siRNA was constructed and then transfected into U2OS cells. A stable transfection cell clone U2OS/pSUPER-c-FLIP-siRNA was screened from the c-FLIP-siRNA transfected cells. RT-PCR and Western blotting were applied to measure the expression of c-FLIP at the levels of mRNA and protein. The results indicated that the expression of c-FLIP was significantly suppressed by the c-FLIP-siRNA in the cloned U2OS/pSUPER-c-FLIP-siRNA as compared with the control cells of U2OS/pSUPER. The cloned cell line of U2OS/pSUPER-c-FLIP-siRNA was further examined for TRAILinduced cell death and apoptosis in the presence of a pan-antagonist of inhibitor of apoptosis proteins (IAPs) AT406, with or without 4 hrs pretreatment with rocaglamide, an inhibitor of c-FLIP biosynthesis, for 24 hrs. Cell death effects and apoptosis were measured by the methods of MTT assay with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and flow cytometry, respectively. The results indicated that TRAIL-induced cell death in U2OS/pSUPER-c-FLIP-siRNA was increased compared with control cells U2OS/pSUPER in the presence or absence of AT406. Flow cytometry indicated that TRAIL-induced cell death effects proceeded through cell apoptosis pathway. However, in the presence of rocaglamide, cell death or apoptotic effects of TRAIL were similar and profound in both cell lines, suggesting that the mechanism of action for both c-FLIP-siRNA and rocaglamide was identical. We conclude that the inhibition of c-FLIP by either c-FLIP-siRNA or rocaglamide can enhance the sensitivity of U2OS to TRAIL-induced apopotosis, suggesting that inhibition of c-FLIP is a good target for anti-cancer therapy.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1995년도 춘계학술발표회논문집(2)
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• pp.609-615
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• 1995

Chip machining에 의한 U$_3$Si 분말제조시 절삭가공조건이 분말 입도 분포에 미치는 영향을 조사하기 위하여 U$_3$Si ingot를 선반에서 초경공구를 사용하여 절삭속도 및 이송속도를 변화시키면서 chip을 가공하였고, 가공된 chip의 형상을 광학현미경으로 관찰하고 칩의 크기를 측정하였다. 모든 절삭조건에서 톱니모양의 칩(saw toothed chip)이 형성되었으며, 일정한 절삭속도에서 공구의 이송속도를 변화시켰을 때 이송속도가 증가함에 따라 칩 두께의 증가와 함께 chip segment의 폭도 증가하여 chip segment 의 크기가 뚜렷이 증가함을 보였다. 또한 chip segment의 크기는 절삭속도 보다는 공구의 이송속도에 크게 영향을 받는 것을 알 수 있었고 분말의 입도 분포에도 크게 영향을 미치는 것으로 나타났다.

• Nuclear Engineering and Technology
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• 제49권5호
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• pp.1044-1062
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• 2017

The construction project of the Kijang research reactor (KJRR), which is the second research reactor in Korea, has been launched. The KJRR was designed to use, for the first time, U-Mo fuel. Plate-type U-7 wt.% Mo/Al-5 wt.% Si, referred to as U-7Mo/Ale5Si, dispersion fuel with a uranium loading of $8.0gU/cm^3$, was selected to achieve higher fuel efficiency and performance than are possible when using $U_3Si_2/Al$ dispersion fuel. To qualify the U-Mo fuel in terms of plate geometry, the first miniplates [HANARO Miniplate (HAMP-1)], containing U-7Mo/Al-5Si dispersion fuel ($8gU/cm^3$), were fabricated at the Korea Atomic Energy Research Institute and recently irradiated at HANARO. The PIE (Post-irradiation Examination) results of the HAMP-1 irradiation test were analyzed in depth in order to verify the safe in-pile performance of the U-7Mo/Al-5Si dispersion fuel under the KJRR irradiation conditions. Nondestructive analyses included visual inspection, gamma spectrometric mapping, and two-dimensional measurements of the plate thickness and oxide thickness. Destructive PIE work was also carried out, focusing on characterization of the microstructural behavior using optical microscopy and scanning electron microscopy. Electron probe microanalysis was also used to measure the elemental concentrations in the interaction layer formed between the U-Mo kernels and the matrix. A blistering threshold test and a bending test were performed on the irradiated HAMP-1 miniplates that were saved from the destructive tests. Swelling evaluation of the U-Mo fuel was also conducted using two methods: plate thickness measurement and meat thickness measurement.

• 한국스마트미디어학회 학회지
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• 제3권2호
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• pp.44-50
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• 2014

• 지질공학
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• 제32권2호
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• pp.295-310
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• 2022

월악산-속리산 화강암은 SiO₂와 알카리(Na₂O+K₂O) 함량이 높고 CaO와 P₂O₅는 결핍된 원소 특성을 보인다. 또한 화강암의 알루미나 포화지수는 1.3 이상으로 과알루미나질 특성을 보인다. U과 Th의 평균 함량은 각각 8.3과 39.3 ppm으로서 국내 중생대 화강암 중에서 가장 높은 방사성 원소 함량을 보이며, 화강암의 세계 평균보다 약 2배 정도로 높다. 이러한 높은 방사성 원소 함량 특성은 화강암의 고분화 특성과 대륙지각 기원의 암석 성인에 기인한다. U 또는 Th을 함유하는 방사성 광물은 저어콘, 토라이트, 모나자이트, 제노타임, 퍼구소나이트, 우라니나이트 등이다. 화강암의 Th/U 비 평균값이 5.4로서 지각 평균값과 유사하다는 것은 방사성 원소의 화강암 내 분포가 지각 기원 물질의 마그마 작용에 조절되었음을 의미한다. U과 Th에 대한 Zr, Y, HREE 간의 상관관계로 보아, 방사성 원소는 저어콘이나 모나자이트보다는 주로 제노타임에 포함되어 산출되는 것으로 해석된다.

• Nuclear Engineering and Technology
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• 제33권4호
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• pp.375-385
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• 2001

The total burnup in the spent U$_3$Si/Al fuel samples from Hanaro reactor was determined by destructive methods using $^{148}$ Nd, the sum of $^{143}$ Nd and $^{144}$ Nd, the sum of $^{145}$ Nd and $^{146}$ Nd, and the sum of total Nd isotopes($^{143}$ Nd, $^{144}$ Nd, $^{145}$ Nd, $^{146}$ Nd, $^{148}$ Nd and $^{150}$ Nd) monitors. The fractional($^{235}$ U) turnup in the spent fuel samples was also determined by U and Pu mass spectrometric method. The samples were dissolved in a mixture of 4 M HCI and 10 M HNO$_3$ without any catalyst. The separation of U, Pu and Nd from the spiked and unspiked sample solutions was achieved by two sequential anion exchange separation methods. The isotope compositions of these elements, after their separation from the fuel samples were measured by mass spectrometry. The contents of the elements in the spent fuel samples were determined by isotope dilution mass spectrometric method(IDMS) using $^{233}$ U, $^{242}$ Pu and $^{150}$ Nd as spikes. The effective fission yield was calculated from the weighted fission yields averaged over the irradiation period. The difference between total turnup values determined by various Nd monitors were in the range of 1.8%.