• Title/Summary/Keyword: Radical removal

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Effect of bleaching on human teeth and reduced treatment on negative influence -Review (치아 미백제가 치아에 미치는 영향과 부작용 최소화를 위한 처치에 관한 고찰)

  • Choi, Jae-Yoon;Shim, Youn-Soo
    • Journal of Korean society of Dental Hygiene
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    • v.6 no.4
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    • pp.481-493
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    • 2006
  • The purpose of the review article was to summarize and discuss the available information concerning the effect of bleaching on human teeth and reduced treatment on negative influence. Tooth bleaching effect was differ from extent of concentration and application period of a tooth bleaching agent, certainly full knowledge prior treatment about adverse effect possible appearance and follow clinical treatment for the least reduce. It remains unclear in how far those observation may result in significant adverse effect under clinical conditions. Nevertheless, further investigation are necessary to elucidate these aspect more precisely. The findings of the study were as follows : 1. It is recommended to delay placement of restorations after termination of bleaching therapy for at least 1-3 weeks. 2. Reduced negative influence that is clinical feasibility of catalase in protecting bleached surface against Oxygen radical. 3. The residual peroxide in tooth after bleaching seems to be removed by gradual diffusion and it may be possible to eliminate the adverse effect on tooth by using water displacement solution, ethylalcohol and aceton including it for effective removal of free radical oxygen.

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Protective Effects of a Ginseng Component, M altol(2- M ethyl-3- Hydroxy-4- Pyrone) against Tissue Damages Induced By Oxygen Radicals

  • Jae-Gook Shin;Jon
    • Proceedings of the Ginseng society Conference
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    • 1990.06a
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    • pp.45-48
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    • 1990
  • Maltol(2-methyl-3-hydroxy-r-pyrone), a component known to be present in Korean Ginseng root showed an antioxidant action but its potency as an antioxidant was low; about 1150th that of other antioxidants such as p-phenylenediamine , BHA and BHT. However, maltol was able to protect the oxidation adamants in biological systems such as adriamycin-induced membrane damage in isolated cardiomyocytes, parquet-induced toxicities in isolated hepatocytes and repercussion injury in isolated hearts. The antioxidant action of maltol was also shown to be effective in vivo. The antioxidant action of this compound was probably due to the removal of hydroxyl radicals. In view of the roles of oxygen radical in various pathological processes, Korean Ginseng root, which contains several antioxidants including maltol, is expected to have beneficial efforts on the oxygen radical-involved processes. Keywords Maltol, Oxygen free radicals, Lipid preoccupation, Repercussion injury and Korean ginseng

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Protective Effects of a Ginseng Component, Malto1(2-Mlethyl-3-Hydrox)-4-Pyrone) against Tissue Damages Induced By Oxygen Radicals (활성산소에 의한 조직손상에 미치는 인삼성분의 보호효과)

  • Jae-Gook Shin;Jon
    • Journal of Ginseng Research
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    • v.14 no.2
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    • pp.187-190
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    • 1990
  • Maltol(2-methyl-3-hydroxy-r-pyrone), a component known to be present in Korean Ginseng root showed an antioxidant action but its potency as an antioxidant was low: about 1150th that of other antioxidants such as pphenylenediamine, BHA and BHT. However, maltol was able to protect the oxidation damages in biological systems such as adriamycin-induced membrane damage in isolated cardiomyocytes, paraquat-induced toxicities in isolated hepatocytes and reperfusion injury in isolated hearts. The antioxidant action of maltol was also shown to be effective in vivo. The antioxidant action of this compound was probably due to the removal of hydroxyl radicals. In view of the roles of oxygen radical in various pathological proceises, Korean Ginseng root which contains several antioxidants including maltol is expected to have beneficial effects on the oxygen radical-involved processes.

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A Study on Treatment of Livestock wastewater using Fenton Oxidation and Zeolite Adsorption Process (Fenton 산화공정과 Zeolite 흡착공정을 연계한 축산폐수처리에 관한 연구)

  • Cho, Chang-Woo;Kim, Youn-Jeong;Chung, Paul-Gene
    • Journal of Korean Society on Water Environment
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    • v.21 no.5
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    • pp.505-510
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    • 2005
  • The objective of this study was to remove non-biodegradable matters and ammonia ion in livestock wastewater using Fenton oxidation and Zeolite adsorption process. After coagulation process as 1st treatment, non-biodegradable matters remained after 1st treatment were removed by using OH radical produced in Fenton oxidation process. Zeolite as cation adsoption process was used to remove ammonia ion in 2nd treatment water. As a result of treatment using these processes, NBDCOD removal efficiency was over 90% and ammonia ion was almost removed. Most aromatics or polynuclear aromatics like benzene, phenol and scatol in livestock wastewater wasn't detected after Fenton oxidation process.

Voltammetric Studies on Some Thiadiazoles and Their Derivatives

  • Maghraby, A. A. El;Abou-Elenien, G. M.;Rateb, N. M;Abdel-Tawab, H. R.
    • Journal of the Korean Electrochemical Society
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    • v.12 no.1
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    • pp.54-60
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    • 2009
  • The redox characteristics of 2-arylaldehydehydrazono-3-phenyl-5-substituted-2, 3-dihydro-1, 3, 4-thiadiazoles (1a-h) have been investigated in nonaqueous solvents such as 1, 2-dichloroethane (DCE), dichloromethane (DCM), acetonitrile (AN), Tetrahydrofuran (THF), and dimethylsulfoxide (DMSO) at platinum electrode. Through controlled potential electrolysis, the oxidation and reduction products of the investigated compounds had been separated and indentified. The redox mechanism had been suggested and proved. It had been found that all the investigated compounds were oxidized in two irreversible one-electron processes following the well-known pattern of The EC-mechanism; the first electron loss gives the corresponding cation-radical which is followed by proton removal from the ortho-position in the N-phenyl ring forming the radical. The obtained radical undergoes a second electron uptake from the nitrogen in the N = C group forming the unstable intermediate (di-radical cation) which undergoes ring closure forming the corresponding cation. The formed cation was stabilized in solution through its combination with a perchlorate anion from the medium. On the other hand, these compounds are reduced in a single two-electron process or in a successive two one-electron processes following the well known pattern of the EEC-mechanism according to the nature of the substituent; the first one gives the anion-radical followed by a second electron reduction to give the dianion which is basic enough to abstract protons from the media to saturate the (C = O) bond.

Electrokinetic-Fenton Process for Removal of Phenanthrene (동전기-펜턴 공정을 이용한 phenanthrene 오염토양의 정화)

  • 양지원;박지연;김상준;이유진;기대정
    • Journal of Soil and Groundwater Environment
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    • v.9 no.1
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    • pp.47-53
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    • 2004
  • Feasibility of electrokinetic process combined with Fenton-like reaction was investigated for the removal of phenanthrene from contaminated soil. Transport of hydrogen peroxide by electroosmosis and decomposition of phenanthrene by Fenton-like reaction were observed in a model system. Electrical potential gradient and electroosmotic flow (EOF) at 10 mA were higher than those at 5 mA. High accumulated EOF resulted in high removal efficiency of phenanthrene because the large amount of hydrogen peroxide was transfered through the soil. Removal efficiency of phenanthrene by water washing was 8.5% for 7 days. The highest removal efficiency including phenanthrene decomposition was 95.6% for 14 days. After the operation, soil samples with removal efficiency of 95.6% showed low concentrations of phenanthrene and its intermediates. From this result, it was presumed that phenanthrene was decomposed to small molecules or mineralized to water and carbon dioxide due to continuous supply of hydrogen peroxide by electroosmotic flow.

Review of Hair Removal in Traditional Medicine and Its Clinical Application (한의학 임상에서의 제모시술 치료 원리와 활용에 대한 고찰)

  • Jang, In-Soo;Yang, Chang-Sop;Kang, Sei-Young;Sun, Seung-Ho;Lee, Seung-Ho;Choi, Hyug-Yong;Seo, Hyung-Sik
    • Korean Journal of Acupuncture
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    • v.29 no.1
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    • pp.17-22
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    • 2012
  • Objectives : The purpose of this study is to discuss the diagnostic classification of the traditional medicine for pilosis, and the hair removal treatments in traditional medicine and its clinical application. Backgrounds : In recent years, appearance and beauty have become main interest that have positioned in the medical area. In clinical Korean medicine, a variety of methods such as moxibustion, superficial bleeding, multiple microneedling, facial meridian massage, herbal medicine facial pack, laser acupuncture, and intense pulsed light (IPL) have been applied. Methods and Results : Pilosis, a condition of abnormal hair growth, is stated for the first time in the publication, [Pathogenesis and Manifestations of All Diseases] by Chao Yuan-fang in 610 A.D. It shows that pilosis has been recognised as a disease for ages in Asia. Reviewing several publications, we found multiple approaches to pilosis were already existed in korean medicine. They include internal medicinal classification and its' medications. Acupuncture treatments also focused on regulation of radical causes and superficial removal of abnormal hairs. Specific treatments includes body and ear acupuncture, ear acupressure, hypodermic acupuncture, hypodermic acupuncture injection, laser acupuncture treatment. Physical and chemical methods of hair removal were widely invented. we resulted that significant scientific approaches to pilosis are under way in the korean medical field, and found a variety of medical treatments such as herbal medicines and dermatological methods. Conclusions : Hair removal treatments for pilosis in traditional medicine has a long history. Combined with advanced modern technology it can achieve greater advance in cosmetology.

Determination of Efficient Operating Condition of UV/H2O2 Process Using the OH Radical Scavenging Factor (수산화라디칼 소모인자를 이용한 자외선/과산화수소공정의 효율적인 운전 조건도출)

  • Kim, Seonbaek;Kwon, Minhwan;Yoon, Yeojoon;Jung, Youmi;Hwang, Tae-Mun;Kang, Joon-Wun
    • 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.

Preparation and Photonic Properties of CNT/TiO2 Composites Derived from MWCNT and Organic Titanium Compounds

  • Oh, Won-Chun
    • Journal of the Korean Ceramic Society
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    • v.46 no.3
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    • pp.234-241
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    • 2009
  • In this study, CNT/$TiO_2$ composites derived from various titanium alkoxides and multiwalled carbon nanotubes (MWCNTs) were synthesized and characterized. Surface areas and pore volumes of the CNT/$TiO_2$ samples showed catastrophic decrease due to deposition of titanium compounds. Scanning electron microscopy (SEM) results indicated that the MWCNTs were homogenously decorated and well-dispersed onto/into the composites without apparent agglomeration of $TiO_2$ particles. In the X-ray diffraction (XRD) patterns, peaks of anatase and rutile phase were observed. The energy dispersive X-ray spectroscopy (EDX) spectra revealed the presence of major elements such as C and O with strong Ti peaks. According to the photocatalytic results, MB removal by a treatment with CNT/$TiO_2$ composites seems to have an excellent removal effect as order of CTIP, CTNB and CTPP composites due to a photolysis of the supported $TiO_2$, the radical reaction and the adsorptivity and absorptivity of the MWCNTs.

A Study on Removal of Color in Dyeing Wastewater by Ozone Oxidation (오존산화에 의한 염색체수의 색도 제거에 관한 연구)

  • 정순형;최준호
    • Journal of environmental and Sanitary engineering
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    • v.18 no.4
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    • pp.45-51
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    • 2003
  • This study was conducted to remove the color in dyeing wastewater by ozone oxidation process, and the results were summarized as follows ; The 18.3% of BOD and 56.3% TOC were removed as decreasing with pH 1 in dyeing wastewater, containing the polyester reducing process. It showed that terephthalic acid was precipitated at low pH. The color of dyeing wastewater was removed by the first order reaction, and the reaction rate constants at pH 3, 7, 12 were investigated $0.234{\;}min^{-1},{\;}0.215{\;}min^{-1}{\;}and{\;}0.201{\;}min^{-1}$ respectively. It showed that color was more effectively removed with direct reaction of ozone than radical reaction(non-direct reaction). As increasing of the water temperature, the reaction rate constants were increased slightly. It indicated that activity of ozone was improved at high water temperature.