• Journal of Korean Society of Environmental Engineers
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• v.36 no.8
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• pp.534-541
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• 2014

This study investigated a method to determine an efficient operating condition for the $UV/H_2O_2$ process. The OH radical scavenging factor is the most important factor to predict the removal efficiency of the target compound and determine the operating condition of the $UV/H_2O_2$ process. To rapidly and simply measure the scavenging factor, Rhodamine B (RhB) was selected as a probe compound. Its reliability was verified by comparing it with a typical probe compound (para-chlorobenzoic acid, pCBA); the difference between RhB and pCBA was only 1.1%. In a prediction test for the removal of Ibuprofen, the RhB method also shows a high reliability with an error rate of about 5% between the experimental result and the model prediction using the measured scavenging factor. In the monitoring result, the scavenging factor in the influent water of the $UV/H_2O_2$ pilot plant was changed up to 200% for about 8 months, suggesting that the required UV dose could be increased about 1.7 times to achieve 90% caffeine removal. These results show the importance of the scavenging factor measurement in the $UV/H_2O_2$ process, and the operating condition could simply be determined from the scavenging factor, absorbance, and information pertaining to the target compound.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.231-232
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• 2003

과산화수소(hydrogen peroxide, $H_2O$$_2$)는 광화학적 2차 생성물이며, 대기의 산화상태를 알려주는 지시자의 역할을 한다. 과산화수소는 HO$_2$ radical의 self-reaction 으로 생성된다. HO$_2$+ HO$_2$+ M $H_2O$$_2$ + M (1) OH나 HO$_2$ radical은 NOx나 hydrocarbon 과 같은 대표적인 오존 전구물질들을 산화시킨다. 대기 내 수명이 불과 1초 이내인 OH나 HO$_2$ radical을 직접 측정하기란 어려우므로 수명이 1~2 일 정도인 $H_2O$$_2$를 측정하여 이들 radical의 대기 내 농도를 추정할 수 있다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.04a
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• pp.95-96
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• 2002

과산화수소(hydrogen peroxide, $H_2O$$_2$)는 광화학적 이차 생성물이며, 대기의 산화상태를 알려주는 지시자의 역할을 한다 과산화수소는 HO$_2$ 라디칼의 self-reaction 으로 생성된다. HO$_2$＋HO$_2$＋ M$\longrightarrow$$H_2O$$_2$＋M, OH나 HO$_2$ 라디칼은 NOx나 hydrocarbon 과 같은 대표적인 오존 전구물질들을 산화시킨다. 대기 내수명이 불과 1초 이내인 OH나 HO$_2$ 라디칼을 직접 측정하기란 어려우며 수명이 1-2 일 정도인 $H_2O$$_2$를 측정하므로써 이들 라디칼의 대기 내 농도를 예측 할 수 있다. (중략)

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1566-1568
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• 2002

본 논문은 혈당, 콜레스테롤센서에 적용이 가능한 과산화수소($H_2O_2$) 검출방식인 전기화학발광(Electrochemiluminescence:ECL)법 사용에 필요한 전극특성에 관한 연구이다. 전기화학전극으로 Pt박막전극을 사용하였으며, luminol(5-amino-2, 3-dihydro-1, 4-phthala edione)과 과산화수소($H_2O_2$)의 반응으로 발생한 빛을 포토다이오드(photodiode)를 사용하여 전류를 측정하였다. 사용된 전극은 직사각형(rectangular-type), 교차형(interdigitated-type)의 두 가지 형태를 사용하여, 전극간의 거리와 면적에 따른 ECL특성을 측정하였다. ECL 발광 특성은 전극 면적이 증가함에 따라, 전극거리가 감소함에 따라 증가함을 관찰할 수 있었다.

• Applied Biological Chemistry
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• v.37 no.5
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• pp.320-325
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• 1994

These studies were conducted to investigate the chemical composition changes in in vitro digestibility for the improvement of nutritive value of rice straw by alkaline hydrogen peroxide. The content of neutral detergent fiber (NDF), acid detergent fiber (ADF), hemicellulose, cellulose and lignin in rice straw was decreased with higher level of $H_2O_2\;(pH 11.5)$. The content of ADF, cellulose and ash of the rice straw washed after $H_2O_2\;(pH 11.5)$ treatment tended to be increased but NDF, hemicellulose and lignin were decreased with higher concentration of $H_2O_2\;(pH 11.5)$. In the rice straw washed after alkaline hydrogen peroxide treatment the decomposition of cellulose and lignin was effective in $pH\;11.5{\sim}12.5$, in smaller cutting size and $55^{\circ}C$. The in vitro organic matter digestibility was increased with higher $H_2O_2$ concentration and smaller cutting size of rice straw.

• 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.

• Journal of the Korean GEO-environmental Society
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• v.13 no.7
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• pp.49-54
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• 2012

This study focuses on the decomposition of pentachlorophenol(PCP) by an electron beam (E-beam) process. To attain this objective, we investigated the reactive species generated from E-beam process during irradiation (reaction time 0.6 s) and G-values of PCP decomposition and effects of pH and $H_2O_2$ as an additive. The effect of pH values was independent on the decomposition of PCP. However, during E-beam irradiation a scavenging effect of added $H_2O_2$ (> 1mM) for the decomposition of PCP was shown, which was supported by the decreased amounts of $Cl^-$ produced by the decomposition of PCP. Meanwhile, oxalic acid and unidentified organic chlorine compounds as by-products were increased by the addition of $H_2O_2$. Thus, in order to enhance the efficiency of PCP decomposition, the E-beam process has to consider a proper concentration of $H_2O_2$ as a well-known source of strong oxidant hydroxyl radical.

• Journal of Life Science
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• v.29 no.10
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• pp.1164-1170
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• 2019

The present study was carried out to evaluate extracts of Ginko biloba's outer seed coat, their antioxidative effects, and their ability to protect against DNA damage due to hydrogen peroxide ($H_2O_2$) treatments in cultured human keratinocyte (HaCaT) cells. The bioassays applied for determining the antioxidant effects of a G. biloba outer seed coat water extract (GOSWE) and a G. biloba outer seed coat methanol extract (GOSME) included the DPPH and $H_2O_2$ radical scavenging assays. Our results revealed that GOSME had higher activity than GOSWE against $H_2O_2$ radical scavenging activity in in vitro and in vivo bioassays. Treatment with GOSME significantly increased the viability of $H_2O_2-treated$ HaCaT cells. GOSME's ability to protect against DNA damage was observed via the analysis of plasmids in vitro and genomic DNA in $H_2O_2-treated$ HaCaT cells. According to our data, GOSME is able to protect HaCaT cells from $H_2O_2-induced$ DNA damage and apoptosis by blocking cellular damage related to oxidative stress. In conclusion, our study indicated GOSME might serve as a novel agent for the treatment and prevention of skin disorders caused by oxidative stress.

• Journal of Korea Soil Environment Society
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• v.2 no.3
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• pp.49-57
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• 1997

Naturally-occurring iron minerals, goethite and magnetite, were used to catalyze hydrogen peroxide and initiate Fenton-like oxidation of silica sand contaminated with diesel, kerosene in batch systems. Reaction conditions were investigated by varying H$_2$0$_2$concentration(0%, 1%, 15%), initial contaminant concentration(0.2, 0.5, 1.0g diesel and kerosene/kg soil), and iron minerals(1, 5wt% magnetite or goethite). Contaminant degradations in silica sand-iron mineral-$H_2O$$_2$ systems were identified by determining total petroleum hydrocarbon(TPH) concentration. In case of silica sand contaminated with diesel(1g contaminan/kg soil with 5wt% magnetite) addition of 0%, 1%, 15% of $H_2O$$_2$showed 0%, 25%, and 60% of TPH reduction in 8 days, respectively When the mineral contents were varied from 1 to 5wt%, removal of contaminants increased by 16% for magnetite and 13.1% for goethite. The results from system contaminated by kerosene were similar to those of the diesel. Reaction of magnetite system was more aggressive than that of goethite system due to dissolution of iron and presence of iron(II) and iron(III); however, dissolved iron precipitated on the surface of iron mineral and seemed to cause reducing electron transfer activity on the surface and quenching $H_2$$O_2$. The system used goethite has better treatment efficiency due to less $H_2$$O_2$ consumption. Results of this study showed possible application of catalyzed $H_2$$O_2$ system to petroleum contaminated site without addition of iron source since natural soils generally contain iron minerals such as magnetite and goethite.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.4
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• pp.651-656
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• 2001

Ascorbic acid(AsA) is unevenly distributed throughout all body cells and fluids. Multiactivities of AsA in many biological systems and in various scientific fields were reported. In this study we aimed to clarify the inhibitory action of high concentration of AsA on the cell growth in 3T6 fibroblasts. The cells wee exposed to AsA at various concentration. It showed that 3T6 fibroblasts wee dead by the medium which contained AsA at the concentration higher than 0.5 mM. AsA caused hydrogen peroxide ($H_2O$$_2$) generation in a concentration dependent manner. These results suggested that the $H_2O$$_2$ was formed in the medium by AsA and acted as a cytotoxic gent. Moreover, it is supposed that hydroxyl radical (.OH) induced from $H_2O$$_2$also acetd as actively cytotoxic agent. This lethal effect of AsA causing the cell death was inhibited by the addition of catalase in the medium. Therefore, addition of AsA at the normal concentrations stimulate cell growth, but excess concentrations of AsA induce cell death.