• Journal of Soil and Groundwater Environment
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• v.7 no.3
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• pp.95-102
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• 2002

Manganese oxide/ hydrogen peroxide($MnO_2$/${H_2}{O_2}$) reactions were investigated as an alternative to Fenton-like reaction to reduce chlorinated organic compounds in groundwater This system showed high degradation of CT with low ${H_2}{O_2}$concentration($\leq$294mM) at neutral condition, and CT degradation increased with increasing pH values. The rate of CT degradation was not so much dependent on increase in $MnO_2$concentration since increase in production of oxygen during the reaction obstructed reaction of ${H_2}{O_2}$ on the surface of $MnO_2$. These results show that $MnO_2$catalyzed Ponton-like reaction could be a potential alternative method for treating chlorinated organic compounds in groundwater.

• The Korea Journal of Herbology
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• v.26 no.4
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• pp.133-137
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• 2011

Objectives : Socheongryong-Tang (小靑龍湯, SCRT) has been widely used to treat respiratory disease. In this study, we investigated the protective effects of SCRT on hydrogen peroxide-induced hepatotoxicity. Methods : In the mouse primary liver cells, SCRT was pretreated for 1 h, and 1 mM $H_2O_2$ was treated to mouse primary liver cells. Cell viability was analyzed by using 3- 4,5-Dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT) assay. Also, the activity of AST, ALT and LDH were measured for the evaluation the protective effect of SCRT on $H_2O_2$-induced hepatotoxicity. Intracellular ROS level was analyzed by FACS. Results : SCRT pretreatment decreased $H_2O_2$-induced hepatotoxicity and intracellular ROS production. Pretreatment of SCRT significantly reduced the cytotoxic effect induced by $H_2O_2$, associated with reducing DNA fragmentation and AST, ALT, LDH activities. Conclusions : These results suggest that SCRT has protective effect against $H_2O_2$-induced hepatotoxicity.

• International Journal of Aeronautical and Space Sciences
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• v.18 no.2
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• pp.270-278
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• 2017

This paper describes development procedure and verification test results of a bi-propellant thruster using hydrogen peroxide and kerosene. The design thrust of the thruster is about 500 N and six swirl type coaxial injectors were used. The passage type manifolds were employed for the injector head to reduce the response time. The passage was designed to minimize stagnation points and recirculation region to ensure uniform flow distribution and sufficient cooling performance through flow analysis using Fluent. A catalytic igniter using hydrogen peroxide was installed at the center of the injector head. The propellant feeding and spray characteristics were confirmed by hydraulic tests. Combustion tests were performed on design and off-design points to analyze combustion characteristics under various mixture ratio conditions. The combustion test results show that combustion efficiency was over 95 % and chamber pressure fluctuation were less than 1.5 % under all test conditions.

• Journal of the Korea Institute of Military Science and Technology
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• v.19 no.5
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• pp.669-674
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• 2016

The purpose of this study is to demonstrate the suitability of hydrogen peroxide($H_2O_2$) vapor system for platform interior decontamination. Geobacillus stearothermophilus biological indicator(BI) strips and a field tent were used as a biological simulant and as a simulated platform, respectively. Decontamination was performed based on injection rates and tent sizes with exposure time 60 minutes. We standardized the conditions for the field tent decontamination : 8.0 g/min for $30m^3$($H_2O_2$ vapor concentration of 150~500 ppm, relative humidity of 50 %) and 12.0 g/min for $60m^3$($H_2O_2$ vapor concentration of 250~400 ppm, relative humidity of 55 %). Thus we suggest the system is one of the possible candidates for decontamination of platform interiors.

• Journal of Soil and Groundwater Environment
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• v.20 no.5
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• pp.47-51
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• 2015

Biocatalytic degradation of total petroleum hydrocarbons (TPHs) in contaminated soil by hemoglobin and hydrogen peroxide is an effective soil remediation method. This study used a laboratory soil reactor experiment to evaluate the effectiveness of a nonspecific biocatalytic reaction with hemoglobin and H₂O₂ for treating TPH-contaminated soil. We also quantified changes in the soil microbial community using real-time PCR analysis during the experimental treatment. The results show that the measured rate constant for the reaction with added hemoglobin was 0.051/day, about 3.5 times higher than the constant for the reaction with only H₂O₂ (0.014/day). After four weeks of treatment, 76% of the initial soil TPH concentration was removed with hemoglobin and hydrogen peroxide treatment. The removal of initial soil TPH concentration was 26% when only hydrogen peroxide was used. The soil microbial community, based on 16S rRNA gene copy number, was higher (7.1 × 10⁶ copy number/g of bacteria, and 7.4 × 10⁵ copy number/g of Archaea, respectively) in the hemoglobin catalyzed treatment. Our results show that TPH treatment in contaminated soil using hemoglobin catalyzed oxidation led to the enhanced removal effectiveness and was non-toxic to the native soil microbial community in the initial soil.

• Journal of Environmental Science International
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• v.13 no.11
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• pp.987-991
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• 2004

The purpose of this research is to evaluate the removal efficiencies of COD$\_$Cr/ and color for the dyeing wastewater by the different dosages of ferrous solution and H$_2$O$_2$ in Fenton process. In the case of H$_2$O$_2$ divided dosage for the Fenton's reagent 7:3 of H$_2$O$_2$ was more effective than 3:7 to remove COD$\_$Cr/ and color. The results showed that COD$\_$Cr/ was mainly removed by Fenton coagulation, where the ferric ions are formed in the initial step of Fenton reaction. On the other hand color was removed by Fenton oxidation rather than Fenton coagulation. The removal mechanism of COD$\_$Cr/ and color was mainly coagulation by ferrous ion, ferric ion and Fenton oxidation. The removal efficiencies were dependent on the ferric ion amount at the beginning of the reaction. However, the final removal efficiency of COD$\_$Cr/ and color was in the order of Fenton oxidation, ferric ion coagulation and ferrous ion coagulation. The reason of the highest removal efficiency by Fenton oxidation can be explained by the chain reactions with ferrous solution, ferric ion and hydrogen peroxide.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.05a
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• pp.37-40
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• 2009

This study was performed to design of $H_2O_2$/Kerosene catalyst ignition injector and cold flow test to measure the mass flow rate and spray angle. Mass flow rate and spray angle were measured by designed injector through cold flow test. Result of test kerosene mass flow rate was measured 12.88 g/s and 40 deg of spray angle at pressure drop 3 bar as same as design point. And hydrogen peroxide was measured 94.39 g/s at pressure drop 1 bar smaller than design point.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.172-172
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• 2012

Non-thermal plasma has attracted medical researchers, since they showed higher apoptosis rate in cancer cells than normal cells. However, it is hard to conclude general cancer cell specific effect because comparison between normal and cancer cell activities after plasma treatment have not been reported yet. This research proposes a comparison of Dielectric Barrier Discharge (DBD) plasma effect on three normal cells lines and three cancer cells lines. We measured cell number, mitochondria activity (MTS assay) and amount of hydrogen peroxide (H2O2) for three days. The results show that the number of cancer cells decreased more than normal cells following of exposure time. On the other hand, mitochondria activities and amounts of H2O2 increased following of exposure time. In addition, we found that DBD plasma exposure on cell suspension in media and media only illustrated no difference in mitochondria activity, H2O2 quantity, and cell number. Thus, we can confirm higher apoptosis rate in cancer cells which is related to the reactive oxygen species (ROS) generated by DBD plasma. The related molecular mechanisms were investigated further.

• The Korean Journal of Physiology and Pharmacology
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• v.25 no.4
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• pp.297-305
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• 2021

Luteolin, a sort of flavonoid, has been reported to be involved in neuroprotective function via suppression of neuroinflammation. In this study, we investigated the protective effect of luteolin against oxidative stress-induced cellular senescence and its molecular mechanism using hydrogen peroxide (H₂O₂)-induced cellular senescence model in House Ear Institute-Organ of Corti 1 cells (HEI-OC1). Our results showed that luteolin attenuated senescent phenotypes including alterations of morphology, cell proliferation, senescence-associated 𝛽-galactosidase expression, DNA damage, as well as related molecules expression such as p53 and p21 in the oxidant challenged model. Interestingly, we found that luteolin induces expression of sirtuin 1 in dose- and time-dependent manners and it has protective role against H₂O₂-induced cellular senescence by upregulation of sirtuin 1 (SIRT1). In contrast, the inhibitory effect of luteolin on cellular senescence under oxidative stress was abolished by silencing of SIRT1. This study indicates that luteolin effectively protects against oxidative stress-induced cellular senescence through p53 and SIRT1. These results suggest that luteolin possesses therapeutic potentials against age-related hearing loss that are induced by oxidative stress.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.5
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• pp.814-821
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• 1997

Kimchi is composed of many ingredients such as Chinese cabbage, garlic, ginger, and red pepper and fermented fish extract. Some of them were known to have antioxidative activities due to their scavenging effect against reactive oxygen species(ROS). To study the health effects of kimchi on human skin cells, keratinocyte(A431, epidermoid carcinoma, human) and fibroblast(CCD-986SK, normal control, human) were cultured in oxidative stress condition provoked by paraquat, a superoxide anion generator, and hydrogen peroxide in the absence and presence of kimchi extract. The survival rate of keratinocyte was greatly reduced when exposed over 1mM concentration of hydrogen peroxide($H_{2}O_{2}$), but cytotoxicity of $H_{2}O_{2}$ was significantly reduced by kimchi extracts on cells. Especially 2 week-fermented kimchi decreased remarkably the cytotoxicity by $H_{2}O_{2}$ to keratinocyte cells. Over 1mM of paraquat concentration showed strong cell toxicity on keratinocyte, but the extracts from kimchi fermented for 1, 2 and 3 weeks showed protective effects in order. Fibroblast cells were significantly affected by $H_{2}O_{2}$ as were keratinocyte cells. Although almost all extacts of kimchi of different fermentation periods showed protective effect against cell killing at 0.5mM concentration of $H_{2}O_{2}$ week-fermented kimchi extract showed the strongest protective effect on fibroblast cells treated with 1mM $H_{2}O_{2}$ for either 1 day or 4 days. However most of kimchi extracts showed weak preventive effect or no effect on oxidative stress produced by paraquat. In conclusion, 2 week-fermented kimchi extract seems to have the best potential in preventing skin cells against oxidative damage which might be related to their scavenging effects of kimchi components produced during their fermentation process.