• Title/Summary/Keyword: Hydrogen peroxide ($H_2O_2$)

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Measurements of hydrogen peroxide($H_2O$$_2$) in Rainwater at Sihwa (시화호 유역 강수 중 hydrogen peroxide($H_2O$$_2$) 농도 변화 분석)

  • 최성원;장유운;이강웅;이미혜
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2002.04a
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    • pp.111-112
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    • 2002
  • 대기 중에 존재하는 hydrogen peroxide($H_2O$$_2$)는 특별한 source를 통해 배출되기보다는 오존이 광분해 되어 수증기와 반응하여 생성된 hydroperoxy radical (HO$_2$)의 self-reaction이나, 대기 중으로 배출된 VOCs의 산화 과정과 같은 광화학적 기원으로 생성된다. 이렇게 생성된 $H_2O$는 오존(O$_3$), hydroxy radical(OH)과 함께 대기 중으로 배출되는 물질과 반응하여 그 농도를 감소시키는 산화제를 역할을 한다. (중략)

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Inactivation of Escherichia coli O157:H7, Salmonella Enteritidis and Listeria monocytogenes by Hydrogen Peroxide and Lactic acid (과산화수소와 유산ol Escherichia coli O157:H7, Salmonella Enteritidis 및 Listeria monocytogenes의 증식 억제에 미치는 영향)

  • Jang Jae-Seon;Lee Mi-Yeon;Lee Jea-Mann;Kim Yong-Hee
    • Journal of environmental and Sanitary engineering
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    • v.19 no.4 s.54
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    • pp.69-75
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    • 2004
  • The inhibitory effect of the food processing agent on growth of Escherichia coli O157:H7, Salmonella Enteritidis, and Listeria monocytogenes was performed with hydrogen peroxide and lactic acid, and combination of hydrogen peroxide and lactic acid. The minimun inhibitory concentration (MIC) of hydrogen peroxide in E coli O157:H7 was 100 ppm at pH 5.0, 6.0, 6.5 and 7.0, while in Listeria monocytogenes 25 ppm at PH 5.5, 6.0 and 50 ppm at PH 6.5, 75ppm at pH 7.0. MIC of lactic acid in E coli O157:H7 was 2500 ppm at pH 5.0, 6.0, 6.5 and 7.0. MIC of lactic acid in S. Enteritidis was 1250 ppm at pH 5.0, 2500 ppm at pH 5.5, 6.0, 5.5 and 7.0, while in L monocytogenes 625 ppm at pH 5.5 and 125 ppm at pH 6.0, 6.5 and 7.0. MIC of combined hydrogen Peroxide and lactic acid in E. coli O157:H7, S. Enteritidis, and L. monocytogenes was 75 ppm of hydrogen peroxide with 2500 ppm of lactic acid at pH 6.5. The correlations between MICs of hydrogen peroxide and lactic acid in E. coli O157:H7, S. Enteritidis and L. monocytogene were obtained through the coefficient of $determination(R^2)$. $R^2$ value were 0.9994, 0.9935 and 0.9283, respectively. The inhibitory effect of hydrogen peroxide and lactic acid in E. coli O157:H7, S. Enteritidis and L. monocytogenes could be confirmed from the result of this experiment. Therefore, it was expected that the food process would increase or maintain by using lactic acid together with hydrogen peroxide.

Measurement of Hydrogen Peroxide in the Atmosphere of Kwangju (광주시 대기중의 Hydrogen Peroxide 측정)

  • 심재범;홍상범;최중호;이재훈
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2003.11a
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    • pp.315-316
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    • 2003
  • 대기중 광화학반응에서 생산되는 이차 생성물중의 하나인 $H_2O$$_2$(hydrogen peroxide)는 peroxy radicals간의 결합에 의해 생성된다. HO$_2$ + HO$_2$ $\longrightarrow$ $H_2O$$_2$+ $O_2$ 이렇게 생성된 $H_2O$$_2$는 대기중에서 주요 산화제로 작용하며, pH 4.5 이하 수용액 내에서 S(IV)를 S(VI)로 산화시켜 H$_2$SO$_4$(sulfuric acid)를 생성 한다. 또한 $H_2O$$_2$는 대기중에서 odd-hydrogen radicals(OH, HO$_2$, and RO$_2$)의 저장고 역할과 함께 odd-hydrogen radical의 생성과 소멸에 작용하여 대기의 산화력을 반영한다(Lee et al. 2000). (중략)

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Removal of Procymidone by Ozonated Water (오존수를 이용한 프로시미돈의 제거)

  • Choi, Seong-Woo;Park, Shin-Young
    • Journal of Environmental Science International
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    • v.16 no.12
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    • pp.1425-1430
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    • 2007
  • This study was conducted to investigate the effect of ozonated water and ozonated water+hydrogen peroxide treatment of residual procymidone in perilla leaf containing 20 mg/L procymidone. Samples was treated with ozonated water containing 1.0, 2.0 and 3.0 mg $O_3/L$ ozone and hydrogen peroxide water containing 1.0, 2.0 and 3.0 mg $H_2O_2/L$ hydrogen peroxide in pH 5, 7 and 9, respectively, at $15^{\circ}C$. Procymidone removal rate was 26.5% in 7 days at $15^{\circ}C$ and optimum condition of procymidone removal was the case of treating with ozonated water containing 2.0 mg $O_3/L$ and pH 9. As the result procymidone removal rate was about 96.5%. In this case of adding hydrogen peroxide, optimum condition of procymidone removal was $1:0.5{\sim}1(O_3:H_2O_2)$. However, procymidone was nearly removed with the treatment of hydrogen peroxide water only.

Performance Characteristics of Hydrogen Peroxide Mono Propellant PDE (Pulse Detonation Engine) (과산화수소 단일 추진제 PDE의 성능 특성에 관한 수치적 연구)

  • Cho, Heung-Sik;Jeung, In-Seuck;Choi, Jeong-Yeol
    • 한국연소학회:학술대회논문집
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    • 2003.12a
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    • pp.153-157
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    • 2003
  • Supersonic and hypersonic aircrafts must pass wide range of speed to reach high speed region. But for existing engines the most efficient operating speed ranges are decided according to their flying speed, so an engine which mixes several engines like TRJ (Turbo Ramjet) and ARJ (Air Turbo Ramjet) has been planed. This mixed type engine has inefficiency that more than two engines must be installed simultaneously, but the pulse detonation engine (PDE) that uses detonation wave has a strong point that it can operate in all speed range with single engine. This paper deals with the simulation of the pulse detonation engine which uses hydrogen peroxide $(H_2O_2)$ mono propellant. Hydrogen peroxide is low-cost propellant, and it is reacted without oxidizer. Comparison between $H_2-O_2$ mixture with $H_2O_2$ mono propellant about thrust, pressure, temperature and velocity shows that $H_2O_2$ is a very useful propellant.

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Capillary Electrophoresis Detection of Hydrogen Peroxide by Using Titanium Ion and 4-(2-thiazolylazo)resorcinol

  • Vu Phuong, Dong;Yoo, Hoon
    • International Journal of Oral Biology
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    • v.42 no.4
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    • pp.197-201
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    • 2017
  • A novel method for the detection of hydrogen peroxide in aqueous solution was developed via reaction between $H_2O_2$, trivalent titanium ion ($Ti^{3+}$) and 4-(2-thiazolylazo) resorcinol (TAR), resulting in a ternary complex with a maximum UV absorbance at 530 nm. The CE detection of $H_2O_2$ was fast, sensitive and cost-effective without pretreatment procedures. $H_2O_2$ was detected within 15 min at 1 to $100{\mu}M$ range with the lowest detection limit at $1.0{\mu}M$. Under the optimized CE conditions, the concentration of $H_2O_2$ in coffee or tea extract was quantitatively determined. Our results show that CE detection of the ternary complex of $H_2O_2-Ti^{3+}$-TAR has potential applications for the detection of $H_2O_2$ in aqueous sources.

Gene Profile of Mesenchymal Stem Cell Induced by SAC or Hydrogen Peroxide (H2O2) (마늘성분 SAC 및 Hydrogen Peroxide에 의한 줄기세포의 유전자 발현 윤곽)

  • Park, Ran-Sook
    • The Korean Journal of Food And Nutrition
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    • v.25 no.4
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    • pp.863-870
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    • 2012
  • Though hydrogen peroxide ($H_2O_2$) causes a deleterious effect to cells with its reactive oxygen species resulting in cell death, S-allyl cysteine (SAC, a bioactive organosulfur compound of aged garlic extract) has been known to have a cytoprotective effect. Few reported profiles of gene expression of $H_2O_2$ and SAC treated human cord blood derived mesenchymal stem cells (MSC). This study revealed changes in the profile of twenty-one genes grouped by oxidative stress, antioxidant, cell death, anti-apoptosis and anti-aging by quantitative real time PCR. A concentration of $100{\mu}M$ of SAC or $50{\mu}M$ of $H_2O_2$ was applied to MSC which show moderate growth and apoptosis pattern. $H_2O_2$ treatment enhanced expression of eleven genes out of twenty-one genes compared with that of control group, on the contrary SAC suppressed expression of eighteen genes out of twenty-one genes except C ros oncogene. SAC decreased expression of oxidative stress genes such as SOD1, CAT and GPX. These results seemed consistent with reports which elucidated over-expression of NF-${\kappa}$B by $H_2O_2$, and suppression of it by SAC. This study will confer basic information for further experiments regarding the effects of SAC on gene levels.

Application of Hydrogen Peroxide for Alumina Slurry Stability in Cu CMP (구리CMP공정시 알루미나 슬러리 안정성을 위한 Hydrogen peroxide의 적용)

  • Lee, Do-Won;Kim, Nam-Hoon;Kim, In-Pyo;Kim, Sang-Yong;Kim, Tae-Hyoung;Seo, Yong-Jin;Chang, Eui-Goo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.11a
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    • pp.136-139
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    • 2003
  • Copper has attractive properties as a multi-level interconnection material due to lower resistivity and higher electromigration resistance as compared with Alumina and its alloy with Copper(0.5%). Among a variety of agents in Copper CMP slurry, $H_2O_2$ has commonly been used as the oxidizer However. $H_2O_2$ is so unstable that it requires stabilization to use as oxidizer Hence, stabilization of $H_2O_2$ is a vital process to get better yield in practical CMP process. In this article the stability of Hydrogen Peroxide as oxidizer of Copper CMP slurry has been investigated. When alumina abrasive was used, $\gamma$-particle Alumina C had a better stability than $\alpha$-particle abrasive. As adding KOH as pH buffering agent, $H_2O_2$ stability in slurry decreased. Urea hydrogen peroxide was used as oxidizer, an enhanced stability was gotten. When $H_3PO_4$ as $H_2O_2$ stabilizer was added, the decrease of $H_2O_2$ concentration in slurry became slower. Even though adding $H_2O_2$ in slurry after bead milling lead to better stability than in advance of bead milling, it had a lower dispersibility.

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Control of redtide microbes with hydrogen peroxide and yellow loess (과산화수소와 황토를 이용한 적조생물의 제어)

  • Seok, Jong-Hyuk;Jun, Se-Jin
    • Journal of Korean Society of Water and Wastewater
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    • v.23 no.4
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    • pp.491-497
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    • 2009
  • The purpose of this study is to propose a method of controlling redtide microbes which grow abundantly and form harmful algal bloom in eutrophic waterbody with yellow loess and hydrogen peroxide. In the laboratory test, hydrogen peroxide was applied to single species of C. polykrikoides and multispecies of redtide microbes. The seawater was evaluated by the pre-test analysis including chlorophyll-a, luminance and transmittance. The test results showed that both single and mixed species of redtide microbes could be controlled with the dose of 30mg $H_2O_2/L$. Residual hydrogen peroxide was completely decomposed with the addition of powdered yellow loess at 2g/L~10g/L. However, the decomposition rate of residual hydrogen peroxide for sintered granular yellow loess was relatively low compared to the use of powdered one. With the addition of dissolved oxygen concentration was increased at a rate of 0.013 mg DO/mg $H_2O_2$, which is a little lower than the one predicted theoretically. No evidence for any detrimental effects on Artemia, a type of brine shrimps, was shown up to the concentration of 100mg $H_2O_2/L$.

UV-OXIDATIVE TREATMENT OF BIO-REFRACTORY ORGANIC HALOGENS IN LEACHATE: Comparison Between UV/O3, UV/H2O2, and UV/H2O2/O3 Processes

  • Qureshi, Tahir Imran;Kim, Young-Ju
    • Environmental Engineering Research
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    • v.11 no.2
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    • pp.84-90
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    • 2006
  • UV-catalytic oxidation technique was applied for the treatment of bio-refractory character of the leachate, which is generally present in the form of adsorbable organic halogens (AOX). Destruction of AOX was likely to be governed by pH adjustment, quantitative measurement of oxidants, and the selection of oxidation model type. Peroxide induced degradation ($UV/H_2O_2$) facilitated the chemical oxidation of organic halides in acidic medium, however, the system showed least AOX removal efficiency than the other two systems. Increased dosage of hydrogen peroxide (from 0.5 time to 1.0 time concentration) even did not contribute to a significant increase in the removal rate of AOX. In ozone induced degradation system ($UV/O_3$), alkaline medium (pH 10) favored the removal of AOX and the removal rate was found 11% higher than the rate at pH 3. Since efficiency of the $UV/O_3$ increases with the increase of pH, therefore, more OH-radicals were available for the destruction of organic halides. UV-light with the combination of both ozone and hydrogen peroxide ($UV/H_2O_2$ 0.5 time/$O_3$ 25 mg/min) showed the highest removal rate of AOX and the removal efficiency was found 26% higher than the removal efficiency of $UV/O_3$. The system $UV/H2O_2/O_3$ got the economic preference over the other two systems since lower dose of hydrogen peroxide and relatively shorter reaction time were found enough to get the highest AOX removal rate.