• 한국응용약물학회:학술대회논문집
• /
• 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
• /
• pp.260-260
• /
• 1994

Mammalian pyruvate dehydrogenase complex(PDC) enzyme consists of multiple oopies of three major oligomeric enzymes-El, E2 E3. And protein X is one of the enzymatic constituents which is tightly bound to E2 subunit This complex enzyme is responsible for the oxidative decarboxylation of pyruvate producing of acetyl CoA which is a key intermediate for the entry of carbohydrates into the TCA cycle for its complete metabolic conversion to CO$_2$. And the overall activity of the complex enzyme is regulated via covalent nodification of El subunit by a El specific phosphatase ad kinase. Protein X has lipoyl moiety that undergoes reduction and acetylation during ezymatic reaction and has been known h be involved in the binding of E3 subunit to E2 core and in the regulatory activity of kinase. The purification of protein X has not been achieved majorly because of its tight binding to E2 subunit The E2-protein X subcomplex was obtained by the established methods and the detachment of protein X from E2 was accomplished in the 0.1M borate buffer containing 150mM NaCl. During the storage of the subcomplex in frozen state at -70$^{\circ}C$, the E2 subunit was precipitated and the dissociated protein X was obtained by cntrifegation into the supernatant The verification of protein X was accomplished by (1)the migration on SDS-PAGE, (2)acetylation by 〔2$\^$-l4/C〕 pyruvate, and (3)internal amino acid sequence analysis of tryptic digested enzyme.

• Transactions on Electrical and Electronic Materials
• /
• 제8권6호
• /
• pp.260-264
• /
• 2007

We have studied stability in organic light-emitting diode depending on buffer layer and cathode. A transparent electrode of indium-tin-oxide(ITO) was used as an anode. An electron injection energy barrier into organic material is different depending on a work function of cathodes. Theoretically, the energy barriers for the electron injection are 1.2 eV, -0.1 eV, and 0.0 eV for Al, LiAl, and LiF/Al at 300 K, respectively. We considered the cases that holes are injected to organic light-emitting diode. The hole injection energy barrier is about 0.7 eV between ITO and TPD without buffer layer. For hole-injection buffer layers of CuPc and PEDOT:PSS, the hole injection energy barriers are 0.4 eV and 0.5 eV, respectively. When the buffer layer of CuPc and PEDOT:PSS is existed, we observed the effects of hole injection energy barrier, and a reduction of operating-voltage. However, in case of PVK buffer layer, the hole injection energy barrier becomes high(1.0 eV). Even though the operating voltage becomes high, the efficiency is improved. A device structure for optimal lifetime condition is ITO/PEDOT:PSS/TPD/$Alq_3$/LiAl at an initial luminance of $300cd/m^2$.

• Journal of the Korean Wood Science and Technology
• /
• 제41권4호
• /
• pp.269-275
• /
• 2013

본 연구는 유기질 문화재 보존을 위해 한국 전통 약용식물을 대상으로 항균 및 살충활성을 검증한 결과 황벽나무 열매 추출물이 우수한 활성을 나타냄을 확인하였다. 황벽나무 열매 추출물을 비극성 용매로 분획하여 그 중 가장 활성이 우수한 ethylacetate 분획물을 대상으로 실리카젤 및 Sephadex LH-20 컬럼 크로마토그래피를 실시하고 Prep-TLC를 이용하여 화합물을 순수 분리하였다. 화합물은 UV spectrum 분석 결과 260 nm 파장에서 최대흡수피크가 관찰되었고, $^1H$, $^{13}C$, HMQC, HMBC NMR과 ESI mass spectrum을 이용하여 화학구조를 분석한 결과 (4'-ethyl-2'-methylfuranyl)-6-methoxy-7-methylnona-2E,4E,6Z,8E-tetraenoic acid의 새로운 화합물임을 알 수 있었다.

• 약학회지
• /
• 제48권4호
• /
• pp.254-260
• /
• 2004

Structure-activity relationship studies of allylamine type of antimycotics were carried out to evaluate the effect of naphthyl and methyl portion of naftifine. Compounds with 2,4-difluorophenyl( 2a-5a), 2,5-difluorophenyl(2b-5b), 4-ethylphenyl(2c-5c), 2-hydroxyphenyl(2d-5d) and 2-methylnaphthyl(2e-5e) instead of naphthyl group with hydrogen(3a-3e), methyl(4a-4e), and ethyl(5a-5e) in the place of methyl in naftifine were synthesized and tested their in vitro anti-fungal activity against five different fungi. Eight compounds( 3a, 4a, 5a, 3d, 4d, 4d, 5d, 3e, and 4e) showed significant anti-fungal activity against T. mentagroPhytes. (E)-N-(3-Phenyl-2-propenyl)-2- hydroxy-benzenemethaneamine( 3d) displayed moderate antifungal activity against all five different fungi.

• Bulletin of the Korean Chemical Society
• /
• 제34권1호
• /
• pp.95-98
• /
• 2013

The photoluminescence (PT) properties of Al-doped ZnO thin films grown by the sol-gel dip-coating method have been investigated. At 12 K, nine distinct PL peaks were observed at 2.037, 2.592, 2.832, 3.027, 3.177, 3.216, 3.260, 3.303, and 3.354 eV. The deep-level emissions (2.037, 2.592, 2.832, and 3.027 eV) were attributed to native defects. The near-band-edge (NBE) emission peaks at 3.354, 3.303, 3.260, 3.216, and 3.177 eV were attributed to the emission of the neutral-donor-bound excitons ($D^0X$), two-electron satellite (TES), free-to-neutral-acceptors (e,$A^0$), donor-acceptor pairs (DAP), and second-order longitudinal optical (2LO) phonon replicas of the TES (TES-2LO), respectively. According to Haynes' empirical rule, we calculated the energy of a free exciton (FX) to be 3.374 eV. The thermal activation energy for $D^0X$ in the nanocrystalline ZnO thin film was found to be ~25 meV, corresponding to the thermal dissociation energy required for $D^0X$ transitions.

• 한국전자거래학회:학술대회논문집
• /
• 한국전자거래학회 2003년도 종합학술대회 논문집
• /
• pp.255-260
• /
• 2003

연구배경 □ 어떠한 시간과 장소에서도 사용 가능한(유비쿼터스, 편재형)통신 환경의 실현 Ｏ IPv6의 보급 Ｏ무선 네트워크의 보편화 Ｏ이동단말의 소형화 및 성능향상 Ｏ다양한 서비스와 어플리케이션 등 □유비쿼터스 통신 환경을 기반으로 한 전자상거래(M-, U-Commerce) Ｏ온, 오프 연동 및 유,무선 연동의 비즈니스 모델 Ｏ실물공간과 가상공간의 상거래를 연결, 통합하는 모델 Ｏ기술적으로는 위치기반, 지능화, 개인화된 고객서비스 가능(중략)

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2008년도 추계학술대회 논문집
• /
• pp.259-260
• /
• 2008

• 한국광학회:학술대회논문집
• /
• 한국광학회 2001년도 하계학술발표회
• /
• pp.260-261
• /
• 2001

No Abstract.See Full-text

• Bulletin of the Korean Chemical Society
• /
• 제16권5호
• /
• pp.401-406
• /
• 1995

The P. fragi lipase overexpressed in E. coli as a fusion protein of 57 kilodalton (kDa) has been purified through glutathione-agarose affinity chromatography by elution with free glutathione. The general properties of the purified GST-fusion protein were characterized by observing absorbance of released p-nitrophenoxide at 400 nm which was hydrolyzed from the substrate p-nitrophenyl palmitate. The optimum condition was observed at 25 $^{\circ}C$, pH 7.8 with 0.4 ${\mu}g$ of protein and 1.0 mM substrate in 0.6% (v/v) TritonX-100 solution. Also the lipase was activated by Ca+2, Mg+2, Ba+2 and Na+ but it was inhibited by Co+2 and Ni+2. pGEX-2T containing P. fragi lipase gene as expression vector was named pGL191 and used as a template for the site-directed mutagenesis by sequential PCR steps. A Ser-His-Asp catalytic triad similar to that present in serine proteases may be present in Pseudomonas lipase. Therefore, the PCR fragments replacing Asp217 to Arg and His260 to Arg were synthesized, and substituted for original fragment in pGL19. The ligated products were transformed into E. coli NM522, and pGEX-2T harboring mutant lipase genes were screened through digestion with XbaI and StuI sites created by mutagenic primers, respectively. No activity of mutant lipases was observed on the plate containing tributyrin. The purified mutant lipases were not activated on the substrate and affected at pH variation. These results demonstrate that Asp217 and His260 are involved in the catalytic site of Pseudomonas lipase.

• 방사성폐기물학회지
• /
• 제11권4호
• /
• pp.293-301
• /
• 2013

처분공 처분 개념은 아프리카의 방사성폐기물관리 방안의 향상을 위해서 남아프리카에너지주식회사(NECSA)에서 처음으로 제시되었다. 초기에 방사성폐기물의 지층처분방안이 고려되었으나, 지하수를 방사성폐기물 오염으로부터 보호하는 방안과 토양과 지하 암석의 균열지대를 통한 방사성 물질의 이동에 대한 조사가 불가피하게 필요했다. 이러한 이유로 처분공 처분개념이 연구되었다. 처분공 처분 개념은 폐기된 밀봉선원을 상대적으로 좁은 직경(260 mm)의 처분공 시설을 통해 처리 및 처분한다. 탄자니아는 장반감기 및 단반감기의 폐기된 밀봉선원을 방사성폐기물관리시설에 저장하고 있으며 폐기된 밀봉선원의 방사능은 1E-6 Ci 에서 8.8E+3 Ci의 범위로 분포한다. 그러나 영구 처분 문제는 여전히 해결하지 못하고 있다. 본 연구에서는 처분부지 면적이 적고, 이에 따라 인간침입 위험이 줄어드는 처분공 처분개념을 제시하였다.