• 한국미생물·생명공학회지
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• 제14권2호
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• pp.169-174
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• 1986

Cytosine deaminase는 세균과 효모에서는 연구되었으나 비교적 진화가 진행된 생물인 곰팡이에서는 전혀 연구되어 있지 않았다. 곰팡이 중 특히. 효소 활성이 높은 Aspergillus fumigatus로부터 cytosine deaminase를 추출하여 부분 정제한 효소의 특성을 규명하였다. 곰팡이의 cytosine deaminase는 pH 5.5-8.0에서 비교적 안정하나, 열 안정성은 아주 낮은 효소였으며 pH 7.0과 30-35$^{\circ}C$에서 반응 최적 조건을 나타내며 활성화 에너지 값(Ea)는 13,240ca1/mol 이었다. 본 효소는 cytosine 뿐만 아니라 5-methylcytosine과 5-fluorocytosine을 기질로 이용하며 cytosine에 대한 km값은 1.53mM이며, 분자량은 32,000 이었다. Cytosine deaminase의 효소 활성은 Hg$^{2+}$, Pb$^{2+}$, Cd$^{2+}$, Fe$^{2+}$에 의하여 저해되며 1mM ATP와 UTP에 의해서도 저해되었다. 더우기 본 효소는 o-phenanthroline, p-chloromercuribenzoate에 의하여 저해되기도 했다.

• Bulletin of the Korean Chemical Society
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• 제19권10호
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• pp.1084-1090
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• 1998

The oxidation of triphenylphosphine by [(tpy)(phen)RuⅣ(O)]2+ and [(bpy)(p-tert-butylpy)RuⅣ(0)]2+ (tpy is 2,2': 6',2"-terpyridine, phen is 1,10-phenanthroline, bpy is 2,2'-bipyridine, and p-tert-butylpy is para-tertbutylpyridine) in CH3CN has been studied. Experiments using 18O-labeled complex show the oxyl group transfer from [RuⅣ=O]2+ to triphenylphosphine occured quantitatively within experimental error. Kinetic data were fit to a second-order for [RuⅣ=O]2+ and [PPh3]. The initial product, [RuⅡ-OPPh3]2+, was formed as an observable intermediate and then underwent slow solvolysis. The reaction proceeded as endothermic in activation enthalpy and a decrease in activation entropy. The oxidative reactivity of four representative ruthenium mono-oxo oxidants against triphenylphosphine was compared. These systems have been utilized as electrochemical oxidative catalysts.

• Journal of Electrical Engineering and Technology
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• 제4권3호
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• pp.418-422
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• 2009

We synthesized new electroluminescence materials [(1,10-phenanthroline)(8-hydroxyquinoline)] Zn(phen)q and investigated their electron transport properties. We used Zn(phen)q and $Alq_3$ for the conductive materials and measured their electron transport properties as a function of the organic layer thickness. The difference between Zn(phen)q and $Alq_3$ as electron transporting materials suggests that the electrical properties depends on the carrier injection.

• 한국전기전자재료학회논문지
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• 제22권4호
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• pp.323-326
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• 2009

We have developed blue-emitting phosphorescent organic light emitting diodes (OLEDs) using 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) and tris (8-quinolinolato)aluminum ($Alq_3$) electron transport layers. As blue dopant and host materials, bis[(4,6-di-fluorophenyl)-pyridinate-N,C2']picolinate (FIrpic) and N,N'-dicarbazolyl-3,5-benzene (mCP) were used, respectively. The driving voltage, current efficiency and emission characteristics of devices were investigated. While the driving voltage was about $1{\sim}2$ V lower in the device with an $Alq_3$ layer, the current efficiency was about 66 % higher in the device with BCP electron transport layer. the blue phosphorescent OLED with BCP layer exhibited higher purity of color, resulting from a relatively weak electroluminescence intensity at 500 nm.

• 대한의생명과학회지
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• 제10권4호
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• pp.415-420
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• 2004

Fibrinolytic substance was purified from the Wooltalikong (Phaseolus ssp.), using DEAE-cellulose chromatography, Sephadex G-150 gel-filtration, and FPLC gel-filtration. The substance has a molecular weight of 5262.70 Da as measured by MALD-TOF mass spectrometry. It has a pH optimum at pH 6.0. The fibrinolytic activity of purified substance was inhibited by EDTA and 1,10-phenanthroline and slightly decreased by PMSF and pepstatin A. It shows the maximum fibrinolytic activity at 40℃ and the substance was stable up to 50℃. The activity of the substance was increased by Zn/sup 2+/ and was totally inhibited by Hg/sup 2+/. This study revealed that Wooltalikong could be a good source of fibrinolytic products due to its small molecular size and heat-resistant ability.

• Applied Science and Convergence Technology
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• 제24권6호
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• pp.278-283
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• 2015

In this work, the electrical bistability of an organic CT complex is demonstrated and the possible switching mechanism is proposed. 2,9-Dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) and tetracyanoquinodimethane (TCNQ) are used as an organic donor and acceptor, respectively, and poly-methamethylacrylate (PMMA) is used as a polymeric matrix for spin-coating. A device with the Al/($Al_2O_3$)/PMMA:BCP:TCNQ[1:1:0.5 wt%]/Al configuration demonstrated bistable and switching characteristics similar to Ovshinsky switching with a low threshold voltage and a high ON/OFF ratio. An analysis of the current-voltage curves of the device suggested that electrical switching took place due to the charge transfer mechanism.

• Journal of Life Science
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• 제9권1호
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• pp.64-68
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• 1999

The properties of purified intracellular adenosine deaminase (adenosine aminohydrolase, EC 3.5.4.4) of Nocardioides sp. J-326TK isolated from soil have been studied. The enzyme deaminated adenosine and 2`-deoxyadenosine and the respective {TEX}$K_{M}${/TEX} values were 4.0×{TEX}$10^{-4}${/TEX} M and 5.0× {TEX}$10^{-4}${/TEX} M, but the enzyme was not active on 8-bromoadenosine, 6-methylaminopurine riboside, ATP, ADP, 2`-AMP, 3`-AMP, 5`-AMP, dAMP, cAMP, NAD, FAD, NADP and adenine. The enzyme activity was strongly inhibited by the addition of {TEX}$Hg^{2+}${/TEX} and {TEX}$Ag^{+}${/TEX}, {TEX}$Cu^{2+}${/TEX}, {TEX}$Co^{2+}${/TEX} and {TEX}$Mn^{2+}${/TEX} also inhibited the activity but much less extent. The effect of alkyl reagents, metal chelating reagents and certain other compounds on the enzyme activity were also examined. No reagent activated the enzyme. On the contrary, the enzyme reaction was slightly inhibited by o-phenanthroline and 6-benzyladenosine.

• 한국전기전자재료학회논문지
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• 제24권8호
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• pp.678-681
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• 2011

We have investigated the effect of organic thin film on the driving voltage of OLED (organic light emitting diode) by inserting a 5 nm thick 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) or triphenylphosphineoxide ($Ph_3PO$) between tris-(8-hydroxyquinoline)aluminum ($Alq_3$) electron transport layer and 4,4'-bis(2,2'-diphyenylvinyl)-1,1'-biphenyl (DPVBi) emission layer. The device with 5 nm thick $Ph_3PO$ layer exhibited higher maximum current efficiency and lower driving voltage than the device with BCP layer, resulting from better electron injection from $Alq_3$ to DPVBi in the device with $Ph_3PO$ layer.

• 한국산학기술학회논문지
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• 제15권1호
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• pp.569-574
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• 2014

오폐수 처리에 있어서 용존산소량을 장기간, 연속측정이 가능한 DO 센서의 개발이 요구되어, 형광검출 특성을 이용한 광학식 DO 센서를 개발하고 특성을 분석하였다 (OS-100, 글로벌광통신주식회사). 형광 센서막은 GA를 이용하여 졸-겔 방법을 이용하여 $Ru(Dpp)_3{^{2+}}$(tris(4,7diphenyl-1, 10-phenanthroline) ruthenium(II)) 형광물질을 제작하였고, 용액과 혼합하여 스프레이 방법으로 석영기판위에 증착하였다. 증착된 형광막은 용존산소 농도 3 mg/L에서 10 mg/L 사이의 넓은 영역에서 ${\pm}1%$ 이하의 오차를 보였다. 제작된 광학식 DO 센서의 성능평가를 위하여 대구염색단지의 오폐수처리장 폐수의 실시간 용존산소를 장기간 측정하였다. 6개월간의 장기간에 걸쳐 실시간 측정된 용존산소의 결과는 염색공단 폐수의 악조건 하에서도 ${\pm}2%$ 이하의 오차를 나타내었다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.1042-1045
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• 2006

The electrical and optical properties of electrophosphorescent organic light-emitting diodes (OLEDs) with modified hole blocking layer (HBL) were investigated. Well-known 2,9-dimethyl-4,7- diphenyl-1,10-phenanthroline (BCP) HBL is mixed with electrophosphorescent host material (4,4'-N,N'- dicarbazole-biphenyl: CBP) or electrophosphorescent dopant material (fac-tris(2-phenylpyridine) iridium: $Ir(ppy)_3$) or both. The highest external quantum efficiency was obtained in the device with $BCP-CBP-Ir(ppy)_3$ mixed HBL and we attribute this result to the additional charge recombination in mixed-HBL.