• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1996년도 춘계학술발표회논문집(3)
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• pp.423-428
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• 1996

The feasibility study on burning Am-241, 243 and Cm-244 nuclides in a conventional PWR (Pressurized Water Reactor) was carried out by using the TRIFON code that was developed by the Institute of Theoretical and Experimental Physics in Russia in 1992. TRIFON code uses updated ABBN Russian nuclear cross section library. The reference reactor is the Korea nuclear power plant unit 8 (YGN 2). The burning effect of Am-241, 243 and Cm-244 nuclides was studied with UO$_2$(3.5 w/o)fuel assembly and MOX (4.44 w/o) fuel assembly. The loaded mass ratio of Am-241, 243 and Cm-244 nuclides was obtained from the mass ratio of Am-241, 243 and Cm-244 nuclides in 10 year cooling spent fuel with average discharge burnup of 33 GWD/MTU. The effective transmutation rates of Am-241, 243 and Cm-244 nuclides in UO$_2$ fuel assembly were found to be higher than those in MOX fuel assembly. The result from TRIFON code was compared to that from CASMO-3/NEM-3D code system. For more reliable calculation of transmutation for MA(Minor Actinides) more sophisticated decay chain scheme of MA should be investigated and nuclear cross section library of MA should be considerably improved.

• Bulletin of the Korean Chemical Society
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• 제32권9호
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• pp.3361-3366
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• 2011

New Y-type polyester (3) containing nitrophenylazoresorcinoxy groups as NLO chromophores, which are components of the polymer backbone, was prepared and characterized. Polyester 3 is soluble in common organic solvents such as N,N-dimethylformamide and acetone. It shows a thermal stability up to $240^{\circ}C$ in thermogravimetric analysis with glass-transition temperature ($T_g$) obtained from differential scanning calorimetry near $116^{\circ}C$. The second harmonic generation (SHG) coefficient ($d_{33}$) of poled polymer film at the 1064 nm fundamental wavelength is around $4.63{\times}10^{-9}$ esu. The dipole alignment exhibits a thermal stability even at $4^{\circ}C$ higher than $T_g$, and there is no SHG decay below $120^{\circ}C$ due to the partial main-chain character of polymer structure, which is acceptable for NLO device applications.

• Bulletin of the Korean Chemical Society
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• 제29권4호
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• pp.811-816
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• 2008

2,5-Di-(2'-hydroxyethoxy)benzylidenemalononitrile (3) was prepared and polymerized with 2,4-toluenediisocyanate and 3,3'-dimethoxy-4,4'-biphenylenediisocyanate to yield novel T-type polyurethanes 4 and 5 containing 2,5-dioxybenzylidenemalononitrile, nonlinear optical (NLO)-chromophores as part of the polymer backbones. Polyurethanes 4 and 5 were soluble in common organic solvents such as acetone and N,Ndimethylformamide and showed a thermal stability up to $250{^{\circ}C}$ with glass-transition temperatures ($T_g$) in the range $119-146{^{\circ}C}$. The second harmonic generation (SHG) coefficients ($d_{33}$) of poled polymer films at 1064 nm fundamental wavelength were around $5.82{\times}10^{-9}$ esu. The dipole alignment exhibited high thermal stability up to $T_g$, and there was no SHG decay below $140{^{\circ}C}$ due to the partial main-chain character of the polymer structure, which was acceptable for nonlinear optical device applications.

• Bulletin of the Korean Chemical Society
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• 제29권5호
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• pp.933-938
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• 2008

2,4-Di-(2'-hydroxyethoxy)benzylidenemalononitrile (3) was prepared and polymerized with terephthaloyl chloride and adipoyl chloride to yield novel Y-type polyesters 4 and 5 containing dioxybenzylidenemalononitrile groups as NLO-chromophores, which constituted parts of the polymer backbone. The resulting polymers 4 and 5 are soluble in common organic solvents such as acetone and N,N-dimethylformamide. Polymers 4 and 5 showed thermal stability up to 300 ${^{\circ}C}$ in thermogravimetric analysis with glass-transition temperatures obtained from differential scanning calorimetry in the range 83-94 ${^{\circ}C}$. The second harmonic generation (SHG) coefficients ($d_{33}$) of poled polymer films at the 1064 nm fundamental wavelength were around $6.48\;{\times}\;10^{-9}$ esu. The dipole alignment exhibited high thermal stability even at 10 ${^{\circ}C}$ higher than $T_g$ and no significant SHG decay was observed below 105 ${^{\circ}C}$ partially due to the main-chain character of polymer structure, which is acceptable for NLO device applications.

• Bulletin of the Korean Chemical Society
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• 제31권6호
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• pp.1509-1514
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• 2010

Methyl 3,4-di-(2'-hydroxyethoxy)benzylidenecyanoacetate (3) was prepared and condensed with terephthaloyl chloride to yield novel Y-type polyester (4) containing 3,4-dioxybenzylidenecyanoacetate groups as NLO-chromophores, which constituted parts of the polymer main chains. The resulting polymer 4 is soluble in common organic solvents such as acetone and N,N-dimethylformamide. Polymer 4 shows thermal stability up to $280^{\circ}C$ in thermogravimetric analysis with glass-transition temperature obtained from differential scanning calorimetry near $105^{\circ}C$. The second harmonic generation (SHG) coefficient ($d_{33}$) of poled polymer films at the 1064 nm fundamental wavelength is around 2.42 pm/V. The dipole alignment exhibits high thermal stability up to near $T_g$, and there is no SHG decay below $100^{\circ}C$ due to the partial main-chain character of polymer structure, which is acceptable for NLO device applications.

• Bulletin of the Korean Chemical Society
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• 제30권5호
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• pp.1080-1084
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• 2009

Methyl 2,4-di-(2'-hydroxyethoxy)benzylidenecyanoacetate (3) was prepared and polymerized with terephthaloyl chloride to yield a novel Y-type polyester 4 containing 2,4-dioxybenzylidenecyanoacetate groups as NLOchromophores, which constituted parts of the polymer backbone. The resulting polymer 4 is soluble in common organic solvents such as acetone and N,N-dimethylformamide. Polymer 4 showed thermal stability up to 280 ${^{\circ}C}$ in thermogravimetric analysis with glass-transition temperature obtained from differential scanning calorimetry near 108 ${^{\circ}C}$. The second harmonic generation (SHG) coefficient ($d_{33}$) of poled polymer films at the 1064 nm fundamental wavelength was around $3.54\;{\time}\;10^{-9}$ esu. The dipole alignment exhibited a thermal stability up to near $T_g$ and no significant SHG decay was observed below 100 ${^{\circ}C}$ due to the partial main-chain character of polymer structure, which is acceptable for NLO device applications.

• Macromolecular Research
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• 제15권3호
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• pp.234-237
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• 2007

3,4-Bis-(3,4-dicarboxyphenylcarboxyethoxy)-4'-nitrostilbene dianhydride was prepared and reacted with 4,4'-(hexafluoroisopropylidene)dianiline to yield a novel Y-type polyimide containing the 3,4-dioxynitrostilbenyl group as an NLO-chromophore, which constituted part of the polymer backbone. The resulting polyimide was soluble in polar solvents such as acetone and N,N-dimethylformamide. The polymer exhibited good thermal stability up to $370^{\circ}C$ in the thermogravimetric analysis. The glass-transition temperature ($T_g$) obtained from the differential scanning calorimetry thermogram was near to $153^{\circ}C$. The second harmonic generation (SHG) coefficient ($d_{33}$) of the poled polymer film at the fundamental wavelength of $1064\;cm^{-1}$ was around $2.15\;{\times}\;10^{-8}\;esu$ (9.01 pm/V). The dipole alignment exhibited exceptionally high thermal stability even at a temperature $30^{\circ}C$ above the $T_g$, and there was no SHG decay below $180^{\circ}C$ because of the partial main chain character of the polymer structure.

• 대한소아치과학회지
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• 제43권3호
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• pp.299-305
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• 2016

본 연구는 서울대학교 치과병원 소아치과에 내원한 부분 무치증 환자를 대상으로 질환의 원인이 될 수 있는 돌연변이를 규명하고, 그 역할에 대하여 고찰하고자 하였다. 다수의 영구치 결손을 주소로 서울대학교 치과 병원에 내원 한 7세 여아와 어머니를 대상으로 구강검진 및 파노라마 방사선 촬영을 진행하였다. 연구 동의서를 받고, 유전자 검사를 위한 채혈을 시행하였다. PAX9 유전자의 모든 exon에 대해 특이적인 primer를 이용하여 중합효소 연쇄반응을 시행하였으며, 해당 산물을 정제하고 염기서열분석을 진행하였다. 결과는 NCBI Gene Bank와 대조하여 해당 영역의 돌연변이를 조사하였다. 7세 환아는 총 11개의 영구치 결손이 관찰되었으며, 어머니는 총 19개의 영구치 결손이 관찰되었다. 치아 결손 외에 손톱, 모발, 피부, 땀샘과 연관 된 다른 결함은 관찰되지 않았다. 유전자 분석 결과, PAX9의 exon 2 영역에서 nonsense mutation(c.184G>T, $p.Glu62^*$)을 확인하였으며, 대상자 모두에서 이형접합 돌연변이로 관찰되었다. 해당 돌연변이의 결과로 exon 2 내에서 전사 종결이 일어나게 되며, 발현 된 단백질은 정상 단백질에 비하여 280개의 아미노산이 짧은 상태로 발현된다고 추측할 수 있다. 결손된 부분은 paired box domain 및 DNA binding site 등 해당 단백질의 기능에 있어서 필수적인 영역을 포함하고 있으므로, 부분 무치증을 유발했을 가능성이 높다. 또는 해당 돌연변이의 전사체가 nonsense-mediated decay system(NMD system)에 의하여 분해됨으로써 haploinsufficiency를 유발하여 부분 무치증의 원인으로 작용했을 것으로 사료된다.

• 터널과지하공간
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• 제13권1호
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• pp.20-32
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• 2003

균열암반에서 콜로이드를 동반한 방사성 핵종의 이동을 핵종붕괴사슬과 주변암반으로제한적 분자확산을 고려하여 모사하였다. 암반 내 핵종 이동을 모사하기 위한 핵종이동 시스템과 지배 방정식 및 초기/경계 조건을 설정하여 반 해석해를 도출하였으며, 수치적 라플라스 역변환을통하여 반해석해의 검증을 실시하였다. 유사콜로이드의 반응상수가 균열 내에 미치는 영향과 콜로이드의 여과작용이 핵종이동에 미치는 영향 그리고 주변 암반으로 제한적 확산이 핵종이동에 미치는 영향에 대하여 알아보았다. 지하수 내에 존재하는 유사 콜로이드의 양이 많아질수록 균열 내 방사성 핵종이동의 가속현상이 크게 나타났으며 여과 계수가 모든 핵종에 대하여 $10^{-3}$ (m$^{-1}$)보다 클 경우 여과에 의한 핵종 지연을 무시할 수 없었다. 콜로이드 존재로 인한 핵종가속과 더불어, 주변암반으로 방사성핵종의 분자확산이 제한적일 경우에 예측된 핵종가속현상은 확산깊이가 적을수록 더 커지는 것을 알 수 있었고, 이때 가속에 영향을 주는 유효확산깊이가 존재하는 것을 발견할 수 있었다. 또한 주변암반의 저지계수가 클수록 제한적 확산깊이에 따른 핵종들의 가속범위의 증가를 볼 수 있었다.

• Journal of Microbiology and Biotechnology
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• 제30권4호
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• pp.533-539
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• 2020

A quantitative real-time polymerase chain reaction (QPCR) was applied to estimate biokinetic coefficients of Clostridium cadaveris and Clostridium sporogenes, which utilize protein as carbon source. Experimental data on changes in peptone concentration and 16S rRNA gene copy numbers of C. cadaveris and C. sporogenes were fitted to model. The fourth-order Runge-Kutta approximation with non-linear least squares analysis was employed to solve the ordinary differential equations to estimate biokinetic coefficients. The maximum specific growth rate (μ_max), half-saturation concentration (K_s), growth yield (Y), and decay coefficient (K_d) of C. cadaveris and C.sporogenes were 0.73 ± 0.05 and 1.35 ± 0.32 h^-1, 6.07 ± 1.52 and 5.67 ± 1.53 g/l, 2.25 ± 0.75 × 10¹⁰ and 7.92 ± 3.71 × 10⁹ copies/g, 0.002 ± 0.003 and 0.002 ± 0.001 h^-1, respectively. The theoretical specific growth rate of C. sporogenes always exceeded that of C. cadaveris at peptone concentration higher than 3.62 g/l. When the influent peptone concentration was 5.0 g/l, the concentration of C.cadaveris gradually decreased to the steady value of 2.9 × 10¹⁰ copies/ml at 4 h Hydraulic retention time (HRT), which indicates a 67.1% reduction of the initial population, but the wash out occurred at HRTs of 1.9 and 3.2 h. The 16S rRNA gene copy numbers of C. sporogenes gradually decreased to steady values ranging from 1.1 × 10¹⁰ to 2.9 × 10¹⁰ copies/ml. C. sporogenes species was predicted to wash out at an HRT of 1.6 h.