• Journal of Ecology and Environment
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• v.40 no.3
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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.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.36 no.5
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• pp.491-496
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• 2008

New concept ramjet propulsion system with liquid bipropellant rocket using "Green Propellant" hydrogen peroxide for launch stage is proposed. In this novel concept, hydrogen peroxide gas generator produces hot oxygen at launch stage and kerosene injects to this jet in combustor. For basic study of this new concept ramjet system, investigation of auto-ignition characteristics and combustion of decomposed hydrogen peroxide and kerosene was conducted. In various test cases, auto-ignition and stable combustion was verified. The combustion temperature of 400°C and Fuel/Oxidizer mixture ratio of 0.6 were the limit of auto ignition. Through the experiment results, the possibility of novel concept combined propulsion system using hydrogen peroxide gas generator is ascertained.

• Journal of Pharmacopuncture
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• v.8 no.3
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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.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.317-320
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• 2011

Hydrogen peroxide turbopump was designed for bi-propellant liquid rocket engine using hydrogen peroxide and kerosene as propellants. Turbopump operation was verified through water tests. Design conditions of hydrogen peroxide turbopump were determined, and impeller was designed. Turbine which drives pump was selected from commercial turbocharger. Gas generator was designed by reference from turbine map. Pump, turbine, gas generator were integrated, and turbopump system was constructed. Turbopump supplied water by 1.47 bar of pressure and as well as 3.4 kg/s of mass flow rate.

• Journal of Acupuncture Research
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• v.22 no.6
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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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• v.4 no.2
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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.

• Applied Chemistry for Engineering
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• v.28 no.3
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• pp.369-374
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• 2017

The curtailment of production cost is important for the mass production of biosensors. Since horseradish peroxidase, which is a key material of enzyme electrodes for hydrogen peroxide analysis is rather expensive, this has been a limiting factor for fabricating carbon paste based enzyme electrodes. In this paper, the acacia leaf tissue as a zymogen easily obtainable in our living environment was used as an alternative to horseradish peroxidase for developing a hydrogen peroxide sensor and the electrochemical properties were evaluated. Ten or more electrochemical parameters alongside the other experimental results acquired by the potentiostatic method demonstrated that our enzyme electrodes can be used for the quantitative analysis of hydrogen peroxide. This also indicates that acacia leaves can take the place of the marketed peroxidase.

• The Plant Pathology Journal
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• v.29 no.4
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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.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.5
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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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• v.33 no.3
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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.