• 한국환경생물학회:학술대회논문집
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• 한국환경생물학회 2002년도 춘계공동학술대회 및 심포지움 초록집
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• pp.66-66
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• 2002

• 한국재료학회지
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• 제4권8호
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• pp.915-920
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• 1994

Diglycidy1 ether of bisphenol A(DGEBA)-Mthylene dianiline(MDA)계에 사슬 확장제인 Succinonitrile(SN)과 반응 촉진제인 Hydroquinone(HQ)을 혼합한 계의 열적 성질을 연구하였다. SN과 HQ의 함량을 4:1로 고정시키고 HQ의 함량을변화시키면서 유리전이 온도와 열변형 온도 그리고 열 분해 온도를 측정하였다. HQ의 함량이 증가함에 따라 유리전이 온도와 열 변형 온도가 약간 감소하였으며 열 분해 온도는 HQ의 함량과 경화 온도의 변화에 따라 $360^{\circ}C$정도의 안정한 값을 나타내었다.

• 한국재료학회지
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• 제6권3호
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• pp.291-296
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• 1996

Diglycidy1 ether of bisphenol A (DGEBA)/4, 4' -methylene dianiline(MDA)에 hydroquinonepheny1 glycidy1 ether(HQ-PGE)를 첨가한 계의 경화반응 메카니즘 FT-IR을 이용하여 연구하였다. 15$0^{\circ}C$에서 경화반응이 일어날 경우 반응기간이 증가할 때 에폭시기와 히드록시기는 감소하였고, 에테르기는 증가하였다. 그리고, HQ-PGE의 함량이 증가함에 따라 에폭시기의 소모량이 증가하였고, 유리 전이 온도가 감소하였다. 이로부터 HQ-PGE는 반응에 참여할 때 사슬 확장제와 반응 가속제로 작용함을 할 수 있었다.

• 한국재료학회지
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• 제4권7호
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• pp.823-827
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• 1994

Diglycidy1 ether of bisphenol A(DGEBA)/4, 4'-methylene dianiline(MDA) 계에 malononitrile(MN)과 hydroquinone(HQ)을 도입한 계의 기계적 특성을 연구하였다. $80^{\circ}C$에서 1.5hr경화시킨후, $150^{\circ}C$에서 1hr 더 경화시킨 시편을 제조하여 시험하였으며, 사슬확장제로 작용하는 MN과 반응 가속제로 작용하는 HQ가 기계적 물성에 미치는 영향을 연구하였다. MN과 HQ의 첨가량이 증가함에 따라 충격특성은 크게 개선된 반면, 딘장특성은 감소하였다.

• 공업화학
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• 제5권6호
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• pp.967-974
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• 1994

DGEBA(Diglycidyl ether of bisphenol A)/MDA(4, 4' -methylene dianiline)/MN(Malononitrile)/HQ(Hydroquinone)계의 경화 반응속도론을 differential scanning calorimetry(DSC)의 승온적 방법(dynamic runs)에 의해 Barrrett method와 Integral method로 연구하였다. 활성화 에너지, pre-exponential factor와 같은 kinetic parameter들이 구하여 졌으며 반응 차수는 본계가 n차 반응 속도식에 적용된다는 가정하에 추정되었다. MN(Malononitrile)은 본 반응의 사슬 연장제로, HQ(Hydroquinone)은 반응 가속제 또는 촉매로 도입되었다.

• The Korean Journal of Physiology and Pharmacology
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• 제21권5호
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• pp.547-554
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• 2017

Previous studies have demonstrated the role of hydroquinone (HQ), a hydroxylated benzene metabolite, in modulating various immune responses; however, its role in macrophage-mediated inflammatory responses is not fully understood. In this study, the role of HQ in inflammatory responses and the underlying molecular mechanism were explored in macrophages. HQ down-regulated the expression of interferon $(IFN)-{\beta}$ mRNA in LPS-stimulated RAW264.7 cells without any cytotoxicity and suppressed interferon regulatory factor (IRF)-3-mediated luciferase activity induced by TIR-domain-containing adapter-inducing interferon-${\beta}$ (TRIF) and TANK-binding kinase 1 (TBK1). A mechanism study revealed that HQ inhibited IRF-3 phosphorylation induced by lipopolysaccharide (LPS), TRIF, and AKT by suppressing phosphorylation of AKT, an upstream kinase of the IRF-3 signaling pathway. IRF-3 phosphorylation is highly induced by wild-type AKT and poorly induced by an AKT mutant, AKT C310A, which is mutated at an inhibitory target site of HQ. We also showed that HQ inhibited IRF-3 phosphorylation by targeting all three AKT isoforms (AKT1, AKT2, and AKT3) in RAW264.7 cells and suppressed IRF-3-mediated luciferase activities induced by AKT in HEK293 cells. Taken together, these results strongly suggest that HQ inhibits the production of a type I IFN, $IFN-{\beta}$, by targeting AKTs in the IRF-3 signaling pathway during macrophage-mediated inflammation.

• Bulletin of the Korean Chemical Society
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• 제34권6호
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• pp.1755-1762
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• 2013

A graphene-Zn/Al layered double hydroxide composite film was simultaneously prepared by electrochemical deposition on the surface of a glassy carbon electrode (G-LDH/GCE) from the mixture solution containing GO and nitrate salts of $Zn^{2+}$ and $Al^{3+}$. The modified electrode showed good electrochemical performances toward the simultaneous electrochemical detection of hydroquinone (HQ), catechol (CA) and resorcinol (RE) due to the unique properties of graphene (G) and LDH such as large active surface area, facile electronic transport and high electrocatalytic activity. The redox characteristics of G-LDH/GCE were investigated with cyclic voltammetry and differential pulse voltammetry. The well-separated oxidation peak potentials, corresponding to the oxidation of HQ, CA and RE, were observed at 0.126 V, 0.228 V and 0.620 V respectively. The amperometric response of the modified electrode exhibited that HQ can be detected without interference of CA and RE. Under the optimized conditions, the oxidation peak current of HQ is linear with the concentration of HQ from 6.0 ${\mu}M$ to 325.0 ${\mu}M$ with the detection limit of 0.077 ${\mu}M$ (S/N=3). The modified electrode was successfully applied to the direct determination of HQ in a local tap water, showing reliable recovery data.

• 한국재료학회지
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• 제5권5호
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• pp.606-610
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• 1995

Diglycidyll ether of bisphenol A(DGEBA)/4, 4'-methylene dianiline(MDA)계에 반응성 첨가제 malononitrile(MN)을 첨가하면 내충격성은 크게 향상되나 반응속도는 감소하게 된다. 에폭시 수지의 경화반응은 에폭시기가 개환되어 생성되는 히드록시기가 촉매로 작용하는 자촉매 반응이며, 외부에서도입된 히드록시기도 같은 효과를 나타낸다. 따라서 본 연구에서는 DGEBA/MDA/MN 계의경화 반응속도를 증가시키기 위해 히드록시기를 가진 촉매로서 hydroquinone(HQ)을 도입하였고 이들 계의경화특성 및 열적성질을 고찰하였다. HQ가 첨가됨으로 인해 활성화 에너지는 감속하고 속도상수는 증가하였으며, 발열곡선에서 반응 시작온도가 낮아졌다. 이 결과로부터 HQ가 반응 가속제로 작용하고 있음을 알 수 있다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 C
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• pp.1588-1590
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• 1996

The fractal characteristics of AC electrical tree grown in DGEBA/MDA/ SN/HQ system was investigated. As the applied voltage decreased, tree initiated after retardation. All the trees were fractals in spite of tile applied voltage. Fractal dimension increased with tree length. When the tree grew slowly, the fractal dimension or tile degree of treeing deterioration increased.

• Asian-Australasian Journal of Animal Sciences
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• 제9권6호
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• pp.715-722
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• 1996

To determine relationships of biochemical parameters involved in Ca metabolism with eggshell quality, serum Ca level, duodenal and uterine calcium binding protein (CaBP) and uterine carbonic anhydrase (CA) activities were measured using 102-week old hens. Three groups of chickens were selected, those showing high quality (HQ) and low quality (LQ) eggshells and non-laying activity (NE). NE hens exhibited significantly (p < 0.05) lower serum Ca levels than laying hens. HQ and LQ hens were not different in the Ca level, indicating that serum Ca level was not good indicator of hen's ability to produce different quality eggshells. Duodenal CaBPs was highest in HQ and lowest in NE (p < 0.10). Uterine CaBPs of LQ and NE were not different and lower significantly (p<0.10) than that of HQ, suggesting that CaBP played an important role in determining eggshell quality. Uterine CA activities of the three groups were significantly different (p < 0.01) ; highest in HQ and lowest in NE, suggesting intimate relationship between CA and Eggshell quality.