• Journal of Ecology and Environment
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• 제40권3호
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• pp.136-143
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• 2016

Background: Mussels are stubborn organisms attached to solid substrata by means of byssus threads. The abundance of marine mussel Mytilus edulis in marine facilities like power stations was reason to select among fouling animals. Methods: Mortality patterns as well as physiological behavior (oxygen consumption, foot activity, and byssus thread production) of two different size groups (14- and 25-mm shell length) of M. edulis were studied at different hydrogen peroxide concentrations ($1-4mg\;l^{-1}$). Results: Studied mussels showed progressive reduction in physiological activities as the hydrogen peroxide concentration increased. Mussel mortality was tested in 30 days exposure, and 14 mm mussels reached the highest percentage of 90% while 25 mm mussels reached 81%. Produced data was echoed by Chick-Watson model extracted equation. Conclusions: This study points that, while it could affect the mussel mortality moderately in its low concentrations, hydrogen peroxide has a strong influence on mussels' physiological activities related to colonization. Therefore, hydrogen peroxide can be an alternative for preventing mussel colonization on facilities of marine environment.

• 한국항공우주학회지
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• 제36권5호
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• pp.491-496
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• 2008

본 연구에서는 RBCC (Rocket Based Combined Cycle)엔진이나 기존 램제트 추진기관의 초기 추력 제공에 과산화수소 가스발생기를 이용하는 새로운 추진시스템을 제안하였고, 기초 연구 수행으로서 촉매 분해된 과산화수소 제트에 케로신을 분사하여 자연발화 및 연소 특성을 연구하였다. 과산화수소는 촉매 베드를 통하여 분해된 후 축소노즐을 통해 연소실로 분사됐으며 이 제트에 인젝터를 통하여 수직으로 케로신을 액상으로 분무하였다. 연소실내에서의 온도와 압력을 측정하여 점화를 확인하고 자연발화 특성을 조사하였다. 400°C의 연소실 온도와 연료와 산화제 혼합비 0.6이상에서 자연발화와 안정적인 연소가 가능하였다. 이 결과를 통하여 램제트의 새로운 초기 가속장치의 가능성을 확인할 수 있었다.

• 대한약침학회지
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• 제8권3호
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• pp.57-69
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• 2005

Objectives : Neurological disorders have been one of main therapeutic targets of acupuncture. The present study investigated the protective effects of Gwakhyangjeonggisan herbal acupuncture solution (GHAS). Methods : We performed 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in glioblastoma cells, and did microarray analysis with cells exposed to reactive oxigen species (ROS) of hydrogen peroxide by 8.0 k Human cDNA, with cut-off level of 2-fold changes in gene expression. Results : MTT assay showed protective effect of GHAS on the glioblastoma cells exposed to hydrogen peroxide. When glioblastoma cells were exposed to hydrogen peroxide, 24 genes were downregulated. When the cells were pretreated with GHAS before exposure to hydrogen peroxide, 46 genes were downregulated. Many of the genes downregulated by hydrogen peroxide stimulation were decreased in the amount of downregulation or reversed to upregulation. Conclusions : The gene expression changes observed in the present study are supposed to be related to the protective molecular mechanism of GHAS in the glioblastoma cells exposed to ROS stress.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2011년도 제37회 추계학술대회논문집
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• pp.317-320
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• 2011

과산화수소와 케로신을 이용한 이원액체추진제 로켓엔진을 위한 산화제 터보펌프를 설계하였으며 수류시험을 통해 설계된 터보펌프의 작동여부를 실험하였다. 과산화수소 터보펌프의 설계조건을 결정하고 펌프의 임펠러를 설계하였다. 펌프를 구동하기 위한 터빈을 차량용 터보차저로 선정하였으며 터빈 맵을 이용하여 가스발생기를 설계하였다. 펌프, 터빈과 가스발생기를 통합하여 터보펌프 시스템을 구축하였으며 수류시험을 통해 터보펌프 시스템이 1.47 bar의 압력으로 3.4 kg/s의 유량을 공급하는 것을 확인하였다.

• Journal of Acupuncture Research
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• 제22권6호
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• pp.111-123
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• 2005

Objectives : Neurological disorders have been one of main therapeutic targets of acupuncture. The present study investigated the protective effects of Gwakhyangjeonggisan herbal acupuncture solution (GHAS). Methods : We performed 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in glioblastoma cells, and did microarray analysis with cells exposed to reactive oxigen species (ROS) of hydrogen peroxide by 8.0 k Human cDNA, with cut-off level of 2-fold changes in gene expression. Results : MTT assay showed protective effect of GHAS on the glioblastoma cells exposed to hydrogen peroxide. When glioblastoma cells were exposed to hydrogen peroxide, 16 genes were upregulated. When the cells were pretreated with GHAS before exposure to hydrogen peroxide, 22 genes were upregulated. Most of the genes upregulated by hydrogen peroxide stimulation were reversed to downregulation by GHAS. Conclusion : The gene expression changes observed in the present study are supposed to be related to the protective molecular mechanism of GHAS in the glioblastoma cells exposed to ROS stress.

• Transactions on Electrical and Electronic Materials
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• 제4권2호
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• pp.1-4
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• 2003

The purpose of this study was to investigate the characteristics of slurry including phosphoric acid for chemical-mechanical planarization of copper and tantalum nitride. In general, the slurry for copper CMP consists of alumina or colloidal silica as an abrasive, organic acid as a complexing agent, an oxidizing agent, a film forming agent, a pH control agent and additives. Hydrogen peroxide (H$_2$O$_2$) is the material that is used as an oxidizing agent in copper CMP. But, the hydrogen peroxide needs some stabilizers to prevent decomposition. We evaluated phosphoric acid (H$_3$PO$_4$) as a stabilizer of the hydrogen peroxide as well as an accelerator of the tantalum nitride CMP process. We also estimated dispersion stability and zeta potential of the abrasive with the contents of phosphoric acid. An acceleration of the tantalum nitride CMP was verified through the electrochemical test. This approach may be useful for the development of the 2$\^$nd/ step copper CMP slurry and hydrogen peroxide stability.

• 공업화학
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• 제28권3호
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• pp.369-374
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• 2017

바이오센서를 상업적으로 양산하고자 할 때 제작비의 경제성이 고려되어야 한다. 과산화수소를 정량하기 위한 효소전극 제작 시 필수적으로 사용되는, 서양고추냉이로부터 추출된 과산화효소는 대단히 고가이므로 탄소반죽법에 의한 전극제작의 제한 요인이 된다. 이 문제를 우회하고자 본 실험실에서는 생활주변에서 쉽게 얻을 수 있는 재료로 대체하기 위하여 아카시아 잎을 효소원으로 사용하여 과산화수소 센서를 제작하고 그것의 전기화학적 특성을 살펴보았다. 일정전압전류법으로 얻어진 10개 이상의 전기화학적 파라미터와 실험적 결과들은 효소전극이 정량적으로 그 기능을 발휘하고 있음을 보여주었다. 이런 사실들은 시판 과산화효소가 아카시아 잎으로 대체될 수 있음을 보여주는 것이다.

• The Plant Pathology Journal
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• 제29권4호
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• pp.427-434
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• 2013

2R,3R-Butanediol, a volatile compound produced by certain rhizobacteria, is involved in induced drought tolerance in Arabidopsis thaliana through mechanisms involving stomatal closure. In this study, we examined the involvement of nitric oxide and hydrogen peroxide in induced drought tolerance, because these are signaling agents in drought stress responses mediated by abscisic acid (ABA). Fluorescence-based assays showed that systemic nitric oxide and hydrogen peroxide production was induced by 2R,3R-butanediol and correlated with expression of genes encoding nitrate reductase and nitric oxide synthase. Co-treatment of 2R,3R-butanediol with an inhibitor of nitrate reductase or an inhibitor of nitric oxide synthase lowered nitric oxide production and lessened induced drought tolerance. Increases in hydrogen peroxide were negated by co-treatment of 2R,3R-butanediol with inhibitors of NADPH oxidase, or peroxidase. These findings support the volatile 2R,3R-butanediol synthesized by certain rhizobacteria is an active player in induction of drought tolerance through mechanisms involving nitric oxide and hydrogen peroxide production.

• 동의생리병리학회지
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• 제22권5호
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• pp.1293-1298
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• 2008

The purpose of this study is to investigate the effect of a mixture of fermented Artemisiae Argi Folium and fermented Sophorae Radix (FAS) on hydrogen peroxide production within mouse macrophage Raw 264.7 with ethanol (EtOH) and nicotine. Artemisiae Argi Folium is known to have the antibacterial, immune-enhancing properties. And Sophorae Radix is also known to have the antibacterial, anti-inflammatory, anti-allergic properties. EtOH and nicotine are the ones of toxicants which could impair immunocytes like macrophage. EtOH and nicotine reduce the intracellular production of hydrogen peroxide ($H_2O_2$) of Raw 264.7. FAS increased the production of hydrogen peroxide reduced by EtOH and nicotine within Raw 264.7. These results indicate that FAS could restore the immuno-activity of macrophage impaired by EtOH and nicotine.

• Toxicological Research
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• 제33권3호
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• pp.219-224
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• 2017

Lipin1 was identified as a phosphatidate phosphatase enzyme, and it plays a key role in lipid metabolism. Since free radicals contribute to metabolic diseases in the liver, this study investigated the effects of free radicals on the regulation of Lipin1 expression in Huh7 and AML12 cells. Hydrogen peroxide induced mRNA and protein expression of Lipin1 in Huh7 cells, which was assayed by quantitative RT-PCR and immunoblotting, respectively. Induction of Lipin1 by hydrogen peroxide was confirmed in AML12 cells. Hydrogen peroxide treatment significantly increased expression of sterol regulatory element-binding protein (SREBP)-2, but not SREBP-1. Moreover, nuclear translocation of SREBP-2 was detected after hydrogen peroxide treatment. Hydrogen peroxide-induced Lipin1 or SREBP-2 expression was significantly reduced by N-acetyl-$\small{L}$-cysteine treatment, indicating that reactive oxygen species (ROS) were implicated in Lipin1 expression. Next, we investigated whether the hypoxic environments that cause endogenous ROS production in mitochondria in metabolic diseases affect the expression of Lipin1. Exposure to hypoxia also increased Lipin1 expression. In contrast, pretreatment with antioxidants attenuated hypoxia-induced Lipin1 expression. Collectively, our results show that ROS activate SREBP-2, which induces Lipin1 expression.