• Title/Summary/Keyword: Hydrogen-peroxide

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A study on preparation of luminol reagents for crime scene investigation (범죄현장 조사용 루미놀 시약의 제조법에 관한 연구)

  • Lim, Seung;Kim, Jung-mok;Jung, Ju Yeon;Lim, Si-Keun
    • Analytical Science and Technology
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    • v.31 no.1
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    • pp.47-56
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    • 2018
  • Finding the blood left at a crime scene is very important to reconstruct or solve a criminal case. Although numerous reagents have been developed for use at crime scenes, luminol is the most representative. Bluestar Forensic has been used in recent years, but is expensive and cannot be stored after preparation. This study aims to develop a new luminol reagent that can be stored for a long period of time while maintaining the chemiluminescence intensity at the level of Bluestar Forensic. Because luminol dissolves well in aqueous alkaline solutions, the use of sodium hydroxide in the preparation of luminol reagents can promote the decomposition of hydrogen peroxide. Magnesium sulfate, sodium silicate, and potassium triphosphate have been used as hydrogen peroxide stabilizers. The effects of the addition of these substances on the chemiluminescence emission intensity and the storage period of the luminol reagents were confirmed. The addition of a hydrogen peroxide stabilizer was shown to have no significant affect on the chemiluminescence emissions intensity or stabilized pH of the luminol reagent during storage. It also greatly increases the shelf life of the reagents. The use of magnesium sulfate as a hydrogen peroxide stabilizer is the most appropriate. When sodium perborate is used instead of hydrogen peroxide as an oxidizing agent, there is no significant change in the sensitivity and chemiluminescence emissions intensity, but the storage period is shortened. However, after the reaction with blood, the pH of the mixed solution does not increase significantly, and is judged to be more suitable than a reagent made of hydrogen peroxide.

35% Hydrogen Peroxide Gel in the Whitening Effect and Enamel Changes (35% Hydrogen Peroxide Gel의 미백효과 및 법랑질의 변화)

  • Lee, Hye-Jin;Kim, Min-Young;Kim, Kho-Han;Kwon, Tae-Yub
    • Journal of dental hygiene science
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    • v.8 no.4
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    • pp.255-260
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    • 2008
  • The purposes of this study were to examine the effect of 35% hydrogen peroxide (HP) bleaching agent on the changes in physical and chemical characteristics of tooth. The bleached teeth showed an apparent color changes. The whiteness increased linearly within the tested period as the period of bleaching increased. The microhardness between bleached groups after bleaching showed any statistically significant difference according to the paried t-test. The bleached enamel surface showed any apparent morphological changes compared to the enamel which was stored in distilled water only. The difference of the total mineral contents for the distilled water and hydrogen peroxide did not show statistical significance. These results demonstrated that bleaching using 35% hydrogen peroxide were adversely affects application time of experimental group and may confirm the safety of using these agents for a short time in dentist-monitored bleaching.

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Use of Hydrogen Peroxide with Ozone to Simultaneously Reduce MIB and Quench Ozone Residual in Existing Water Treatment Plants Sourcing Water from the Han River (한강을 원수로 하는 오존/과산화수소 고도정수처리공정에서의 MIB제거 및 잔류오존 농도에 관한 연구)

  • McAdams, Stephen R.;Koo, Bon Jin;Jang, Myung Hoon;Lee, Sung Kyoo
    • Journal of Korean Society on Water Environment
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    • v.28 no.5
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    • pp.704-716
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    • 2012
  • This paper provides a detailed account of pilot testing conducted at South Lake Tahoe (California), the Ddukdo (Seoul) water treatment plant (WTP) and the Bokjung (Seongnam) WTP between February, 2010, and February, 2012. The objectives were first, to characterize the reactions of ozone with hydrogen peroxide (Peroxone) for Han River water following sand filtration, second to determine empirical ozone and hydrogen peroxide doses to remove a taste-and-odor surrogate 2-methylisoborneol (MIB) using an advanced oxidation process (AOP) configuration and third, to determine the optimum dosing configuration to reduce residual ozone to a safe level at the exit of the process. The testing was performed in a real-time plant environment at both low- and high seasonal water temperatures. Experimental results including ozone decomposition rates were dependent on temperature and pH, consistent with data reported by other researchers. MIB in post-sand-filtration water was spiked to 40-50 ng/L, and in all cases, it was reduced to below the specified target level (7 ng/liter) and typically non-detect (ND). It was demonstrated that Peroxone could achieve both MIB removal and low effluent ozone residual at ozone+hydrogen peroxide doses less than those for ozone alone. An empirical predictive model, suitable for use by design engineers and operating personnel and for incorporation in plant control systems was developed. Due to a significant reduction in the ozone reaction/decomposition at low winter temperatures, results demonstrate the hydrogen peroxide can be "pre-conditioned" in order to increase initial reaction rates and achieve lower ozone residuals. Results also indicate the method, location and composition of hydrogen peroxide injection is critical to successful implementation of Peroxone without using excessive chemicals or degrading performance.

Protective Effect of 3,5-Dicaffeoylquinic Acid Isolated from Ligularia fischeri against Oxidative Damage in HepG2 Cells (HepG2 세포에서 산화적 손상에 대한 곰취 유래 3,5-Dicaffeoylquinic Acid의 보호 효과)

  • Park, Sun-Young;Kim, Gur-Yoo;Jhoo, Jin-Woo
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.11
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    • pp.1286-1292
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    • 2017
  • This study was conducted to investigate the hepatoprotective effects of 3,5-dicaffeoylquinic acid (3,5-DCQA) isolated from Ligularia fischeri against hydrogen peroxide-induced oxidative stress in HepG2 cells. Antioxidative effects of 3,5-DCQA were determined by measuring antioxidant enzyme [superoxide dismutase (SOD), catalase (CAT) glutathione peroxidase (GPx)] expression levels against hydrogen peroxide-induced oxidative stress using real-time PCR analysis. 3,5-DCQA treatment significantly increased gene expression levels of SOD, CAT, and GPx in a dose-dependent manner ($10{\sim}30{\mu}g/mL$) in HepG2 cells. Hepatoprotective effects were analyzed by measuring glutamic oxaloacetic transaminase (GOT), lactate dehydrogenase (LDH), and gamma-glutamyl transferase (GGT) activities using a biochemistry analyzer in hydrogen peroxide-treated HepG2 cells. 3,5-DCQA treatment significantly reduced GOT, LDH, and GGT activities in a dose-dependent manner ($10{\sim}30{\mu}g/mL$) against increased liver function index enzyme activities induced by hydrogen peroxide oxidative stress in HepG2 cells. The results reveal that 3,5-DCQA compound isolated from Ligularia fischeri can be useful for the development of an effective hepatoprotective agent.

Studies on the Bleaching of Rice-Straw Chemical Pulp (II) -Two-Stages Bleaching- (볏짚화학펄프의 표백에 관한 연구(제2보) -2단 표백-)

  • 강진하;박성종;박성철
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.33 no.3
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    • pp.84-99
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    • 2001
  • This study was carried out to acquire basic data necessary for the use of rice-straw chemical pulp. It investigated the proper bleaching conditions when rice-straw chemical pulp(alkaline sulfite-${Na_2}{S_2}{O_4}$) was bleached using the various kinds of bleaching agents by the two-stages bleaching methods. And, physical properties of pulps bleached with eight kinds of two-stages bleaching methods were tested. The results of this study were as follow; 1. The first-stage bleaching was conducted under the proper conditions with chlorine(C). And then, the proper conditions related to the calcium chlorite(H), hydrogen peroxide(P) and sodium hydrosulfite(Y) bleaching as the second-stage bleaching were investigated. The proper conditions of CH stage were determined to be 0.3% concentration of calcium chlorite, $30^{\circ}C$ of reaction temperature and 20min. of reaction time. For CP stage, the proper conditions of concentration of hydrogen peroxide, reaction temperature and reaction time were 1.5%, $60^{\circ}C$ and 90min., respectively. And for CY stage, the proper conditions were 0.5% concentration of sodium hydrosulfite, $40^{\circ}C$ of reaction temperature and 90min. of reaction time. 2. The first-stage bleaching was conducted under the proper conditions with chlorine dioxide(D). And then, the proper conditions related to the calcium chlorite(H), hydrogen peroxide(P) and sodium hydrosulfite(Y) bleaching as the second-stage bleaching were investigated. The proper conditions of DH stage were determined to be 0.5% concentration of calcium chlorite, $25^{\circ}C$ of reaction temperature and 5min. of reaction time. For DP stage, the proper conditions of concentration of hydrogen peroxide, reaction temperature and reaction time were 1.0%, $70^{\circ}C$ and 90min., respectively. And for DY stage, the proper conditions were 0.3% concentration of sodium hydrosulfite, $50^{\circ}C$ of reaction temperature and 20min. of reaction time. 3. The first-stage bleaching was conducted under the proper conditions with calcium chlorite(H). kAnd then, the proper conditions related to the hydrogen peroxide(P) and sodium hydrosulfite(Y) bleaching as the second-stage bleaching were investigated. The proper conditions of HP stage were determined to be 0.3% concentration of hydrogen peroxide, $30^{\circ}C$ of reaction temperature and 60min. of reaction time. For HY stage, the proper conditions of concentration of sodium hydrosulfite, reaction temperature and reaction time were 2.5%, $60^{\circ}C$ and 30min., respectively. 4. When the rice-straw chemical pulps were bleached with eight kinds of two-stages bleaching methods in the proper conditions mentioned above, respectively, the final brightnesses after CH, CP, CY, DH, DP, DY, HP, and HY bleachings were 62.0, 74.3, 61.4, 58.9, 66.9, 62.9, 50.4 and 60.1, respectively. And strengthes of pulps bleached with DP and DH methods were comparatively higher than those of pulps bleached with other bleaching methods.

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A clean technology development using the molybdenum dissolution reaction with hydrogen peroxide(II) (과산화수소를 이용한 몰리브덴(Mo) 용해반응에 따른 청정기술 개발에 관한 연구(II))

  • 김재우;홍종순;신대윤
    • Journal of environmental and Sanitary engineering
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    • v.14 no.3
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    • pp.116-122
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    • 1999
  • The purpose of this study is to develop new process named "hydrogen peroxide dissolution method". This process used hydrogen peroxide, which is harmless to human body and oxidize molybdenum wire selectively.The advantages of hydrogen peroxide dissolution method were no discharge of noxious matter when dissolution of molybdenum wire which used as the center supporter, reactions occur in room temperature and easy to recover dissolved molybdenum. This study was aimed at gathering the basic data of molybdenum wire dissolution-recovery process and proposes the reaction condition of molybdenum wire dissolution-recovery process and the factors influencing those reactions. The results were as follows:1. In the dissolution of molybdenum wire, the early condition of reaction was $15^{\circ}C$, and the temperature condition of state was $32^{\circ}C$. 2. 1) In the GSL-60W type, P.W.(Piece weight) was 11.89mg, C.R. was $65.6\Omega$. 2) In the FL-20W type, P.W. was 11.60mg, C.R. was $4.6\Omega$. 3. The molybdenum of process water was treated of a precipitation after dry and after stagnation in the one day, the molybdenum of upper water was treated of precipitation after dry and after congelation.

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Hydrogen Peroxide Sensitive Biosensors Based on Mugwort-Peroxidase Entrapped in Carbon Pastes (탄소반죽에 쑥 과산화효소를 고정한 과산화수소 감응 바이오센서)

  • Yoon, Kil Joong
    • Applied Chemistry for Engineering
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    • v.26 no.5
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    • pp.624-629
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    • 2015
  • A biosensor including the homogenized tissue of mugwort embedded in carbon paste, which senses hydrogen peroxide, was constructed and its electrochemical properties were validated using voltammetry. The good linearity of Hanes-Woolf plot implied that the reduction reaction of substrate was catalyzed by mugwort peroxidase at the electrode surface. Also the small value of symmetry factor, 0.28, indicated that electrochemical kinetics of the sensor is very sensitive to the change of electrode potential. Many experimental results collected above proved that the dissociation of hydrogen peroxide is dependent on the catalytic power of mugwort peroxidase qualitatively and quantitatively at the surface of the mugwort electrode. It is our firm belief that the marketed HRP can be replaced with mugwort tissue.

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.

Studies on Bonding Characteristics of Plywood by Kraft Black Liquor and Surface Activators (크라프트펄프 폐액(廢液)과 표면산화제(表面酸化劑)를 이용(利用)한 합판(合板)의 접착특성(接着特性)에 관(關)한 연구(硏究))

  • Chung, In-Ju;Lee, Phil-Woo
    • Journal of the Korean Wood Science and Technology
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    • v.16 no.3
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    • pp.5-16
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    • 1988
  • This experiment was executed to investigate the effect of activation of veneer surface by oxidizing agents, hydrogen peroxide and nitric acid, on bonding characteristics of Malas(Homalium foetidum Benth) plywood, in which the effects of these oxidizing agents amount, pretreatment time, and pressing time and temperatue on shear strength of the plywood were examined and discussed. In this research the activation of veneer surface by oxidants was effective in raising shear strength but the difference in shear strength was not observed between hydrogen peroxide and nitric acid treatment. Hydrogen peroxide treatment, however, seemed to be more profitable to industrial application because of its lower concentration and easier handling than nitric acid. The bonding method by lignin-phenol adhesive through surface activation revealed inferior shear strength to phenol- and urea-formaldehyde adhesive but superior water resistance to urea-formaldehyde adhesive and this bonding method, in addition, have the advantage of lower cost compared with phenol-formaldehyde adhesive, Therefore, this bonding method by lignin-phenol adhesive through surface activation seemed to economical in manufacturing of water-resistant wood panel materials in future.

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Cytochrome c Peroxidase: A Model Heme Protein

  • Erman, James E.;Vitello, Lidia B.
    • BMB Reports
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    • v.31 no.4
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    • pp.307-327
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    • 1998
  • Cytochrome c peroxidase (CcP) is a yeast mitochondrial enzyme which catalyzes the reduction of hydrogen peroxide to water using two equivalents of ferrocytochrome c. The CcP/cytochrome c system has many features which make it a very useful model for detailed investigation of heme protein structure/function relationships including activation of hydrogen peroxide, protein-protein interactions, and long-range electron transfer. Both CcP and cytochrome c are single heme, single subunit proteins of modest size. High-resolution crystallographic structures of both proteins, of one-to-one complexes of the two proteins, and a number of active-site mutants are available. Site-directed mutagenesis studies indicate that the distal histidine in CcP is primarily responsible for rapid utilization of hydrogen peroxide implying significantly different properties of the distal histidine in the peroxidases compared to the globins. CcP and cytochrome c bind to form a dynamic one-to-one complex. The binding is largely electrostatic in nature with a small, unfavorable enthalpy of binding and a large positive entropy change upon complex formation. The cytochrome c-binding site on CcP has been mapped in solution by measuring the binding affinities between cytochrome c and a number of CcP surface mutations. The binding site for cytochrome c in solution is consistent with the crystallographic structure of the one-to-one complex. Evidence for the involvement of a second, low-affinity cytochrome c-binding site on CcP in long-range electron transfer between the two proteins is reviewed.

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