• Title/Summary/Keyword: Hydrogen-peroxide

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Advanced Effects of Pulp Bleaching Treated Hemicellulase (Hemicellulase 처리에 의한 목재 펄프의 고해 효과 변화)

  • Kim, Byong-Hyun
    • Journal of the Korean Graphic Arts Communication Society
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    • v.26 no.1
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    • pp.65-72
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    • 2008
  • Kappa number and brightness were more increased with treatment of endo-xylanase than hydrogen-peroxide. In pulp bleaching process, endo-xylanse was most effective in the other enzyme treatment. Exo-xylanase was effective more than 4 unit treatment. Kappa number was tiny increased with enzyme ratio, but less than 4 unit treatment, increased with hydrogen peroxide treatment ratio. In more than 4 unit acetyl-estease treatment, Kappa number and brightness were not influenced with enzyme treatment ratio, but concentration of hydrogen-peroxide.

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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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Rates and Mechanism of Decomposition of Hydrogen Peroxide by Copper(Ⅱ)-Amines Complexes (구리(Ⅱ)-아민류착물에 의한 과산화수소의 분해반응속도와 메카니즘)

  • Sun-Deuk Kim;Yun-Yeol Shin;Jeong-Eun Park;Chang-Su Kim
    • Journal of the Korean Chemical Society
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    • v.37 no.2
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    • pp.199-205
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    • 1993
  • The decomposition of hydrogen peroxide by copper-amines complexes was studied in the pH range of 7.3∼11.3 by measuring the rate of the decreasing concentration of $H_2O_2$. Decomposition rate of hydrogen peroxide increased with increasing pH, and then decreased with increasing pH successively. The mechanism for this type of reaction involves the formation of peroxo complexes in the rate-determining step preceding deprotonation of hydrogen peroxide and copper-amines complexes.

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THE EFFICACY AND SAFETY OF 6% HYDROGEN PEROXIDE AS HOME TOOTH BLEACHING GEL (가정용치아미백제로서의 6% 과산화수소용액의 효과와 안전성)

  • Han, Soo-Boo;Park, Sang-Hyun;Moon, Hyeock-Soo
    • Journal of Periodontal and Implant Science
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    • v.24 no.2
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    • pp.433-440
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    • 1994
  • The purpose of this investigation was to study the efficacy and safety of 6% hydrogen peroxide gel as a daily home tooth bleaching gel. The subjects consisted of 20 male dental students representing a variety of acquired stain and each subject participated for a 4-week period. Tooth color analysis(Shade determination), sulcus bleeding index, probing depth and probing attachment level were done and recorded at baseline and at the end of each week of study. The results indicated that home bleaching gel containing 6% hydrogen peroxide was effective and caused no gingival inflammation. Sulcus bleeding index, probing depth and probing attachment level showed no change. In conclusion, 6% hydrogen peroxide gel is an effective and safe agent for daily home tooth bleaching.

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Effects of Hydrogen Peroxide Concentration on the Polymerization of p-Phenylphenol in Organic Solvent by Peroxidase

  • Yoo, Young-Je;Yeo, Joo-Sang;Park, Tae-In
    • Journal of Microbiology and Biotechnology
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    • v.5 no.3
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    • pp.177-180
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    • 1995
  • In horseradish peroxidase-catalyzing polymerization of phenol under the water/dioxane solvent system, the optimal concentration of hydrogen peroxide was found to be 10 mmol/I. Feeding of hydrogen peroxide at its optimal concentration improved the polymerization performance by reducing reaction time and increasing molecular weights. Monomer conversions and the molecular weights of the enzymatically produced polymer were in the ranges of 83.1~94.2$%$ and 58000~68000, respectively.

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Protective Effect of Caesalpinia sappan L. on Hydrogen Peroxide

  • Yoo Yeong Min;Lee Seon Goo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.6
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    • pp.1524-1527
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    • 2003
  • In this study, we demonstrated the antioxidant effect of the Caesalpinia sappan L. extract through the scavenging effect against 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and the protective effect on protein damage and PC12 cells against cupric ion/hydrogen peroxide. Its IC/sub 50/ value of the scavenging effect against DPPH radical was 7.7 ㎍. Protection of its extract against oxidative bovine serum albumin (BSA)damage induced by hydrogen peroxide was more effective than that of vitamin C. The protective effect on PC12 cells by hydrogen peroxide was shown to be more potent in is extract than in vitamin C. DNA fragmentation analysis also supports this result.

Enhanced Expression of Glucose 2-Oxidase in Phlebia tremellosa by Addition of Phthalates

  • Kim, Baik-Joong;Kim, Hye-Won;Choi, Hyoung-T.
    • Mycobiology
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    • v.39 no.1
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    • pp.64-66
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    • 2011
  • Most fungi possess several hydrogen peroxide-generating enzymes, glucose oxidase and pyranose oxidase. Pyranose oxidase can use glucose as its substrate to generate hydrogen peroxide. White rot fungi, which degrade diverse recalcitrant compounds, contain lignin-degrading enzymes, and lignin peroxidase and manganese peroxidase require hydrogen peroxide for their enzymatic reactions. In this study, we isolated a cDNA fragment of pyranose oxidase from Phlebia tremellosa using PCR and examined its expression under the degradation conditions of diethylphthalate (DEP). Pyranose oxidase expression was enhanced up to 30% by the addition of DEP, and this result supports the possible involvement of pyranose oxidase in the degradation of recalcitrant compounds.

Effect of brazilin on phosphatase activity in isolated rat epididymal adipocytes

  • Lee, Yong-Khil;So, Dhong-Soo;Moon, Chang-Kiu
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1996.04a
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    • pp.218-218
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    • 1996
  • Brazilin은 포도당 수송을 증가시키는 물질로 autooxidation에 의하여 산화되면서 hydrogen peroxide를 생성할 것으로 추정되었으며, hydrogen peroxide는 phosphatase를 억제하여 포도당 수송을 증가시키는 것으로 보고되었다. 따라서 본 실험에서 brazilin의 산화에 의한 hydrogen peroxide의 생성여부를 확인하고 phosphatase 활성에 미치는 braziline의 작용을 살펴보았다. 먼저 UV absorption spectra를 이용하여 brazilin이 반응액중에서 구조적인 변화를 일으키는지 확인하였다. Hydrogen peroxide의 생성은 rhodamine 123를 이용한 형광측정법으로 측정하였으며, phosphatase의 활성은 pH에 따른 phosphatase의 활성을 p-NPP의 탈인산화의 UV 흡광도 변화로 측정하였다. PP2A의 활성은 phosphorylase a를 기질로 하여 측정하였다.

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Assessing the hydrogen peroxide effect along with sodium hypochlorite against marine blue mussels aimed at antifouling usage

  • Haque, Md. Niamul;Kwon, Sunghyun
    • Environmental Engineering Research
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    • v.22 no.1
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    • pp.108-115
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    • 2017
  • Chlorination has been the most common antifouling method, but alternatives are under searching. In this article, we report how the hydrogen peroxide could enhance the effect of chlorination to prevent fouling by inhibiting larvae settlement and abatement of mussel colonization or by extinct of them; through marine mussel Mytilus edulis. The addition of hydrogen peroxide shows synergic effect on the veliger larvae (up to 19 folds) and effectively reduces required time of mussel mortality by 8-22%. For resolution of micro- and macro-fouling caused by the marine mussel, as well as diminishing of time and conventional chlorine dose could be important factor in favour of environment and economics.

The study of manufacturing the oxidizer(Hydrogen Peroxide) feeding system of liquid rocket engine (액체로켓엔진 산화제(과산화수소) 공급계 구축에 관한 연구)

  • Jeon, Jun-Su;Jeong, Jae-Hoon;Kim, Yoo;Ko, Young-Sung;Kim, Sun-Jin
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2009.05a
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    • pp.33-36
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    • 2009
  • This study suggests manufacturing and cleaning the feeding system of hydrogen peroxide to use oxidizer of liquid rocket. We established the process of cleaning and passivation in order to minimize the pollution of Hydrogen Peroxide feeding system. And, we verified stability of the manufactured feeding system by leak test & hot test.

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