• Restorative Dentistry and Endodontics
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• 제23권2호
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• pp.656-669
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• 1998

Hydrogen peroxide at high concentration during walking bleaching may cause damage to the tooth structure and to the surrounding periodontal tissues and may develop external root resorption. Clinically, It is so important to find a method of prevention or minimization of these complications. The efficacy of various chamber-irrigating agents to eliminate residual hydrogen peroxide after walking bleaching was examined and compared with water rinse in this study. Extracted human 46 premolars without any cementoenamel junction defects were treated endodontically and based with IRM to 1 mm below CEJ and totally bleached 3 times for each tooth with 30% hydrogen peroxide and sodium perborate. Upon completion of the 3rd walking bleaching procedure, the cervical portion and pulp chamber of each group of teeth were irrigated with catalase, 70% ethylalcohol, acetone, and distilled water. And then, a radicular hydrogen peroxide penetration was measured with spectrophotometer immediately after each bleaching and following treatment with each chamber-irrigating agents, and the significance of their eliminating efficacy of residual hydrogen peroxide was analyzed by Kruskal-Wallis test. The results were obtained as follows. 1. Cervical root penetration of hydrogen peroxide was increased as the bleaching procedure was repeated(P<.01). 2. The most effective irrigant that removed residual hydrogen peroxide was the catalase, and the least effective one was water rinsing (P<.01).; there was no significant difference between the acetone and ethanol group. 3. The Irrigation with antioxidant enzyme or water-displacement solutions can eliminate residual oxygen radicals from the pulp chamber effectively after walking bleaching. So, these agents can reduce adverse effects such as cervical external resorption and periapical inflammation and prevent residual $O_2$ from impeding composite resin polymerization, thus increase the bonding strength of composite resin. This, in turn reduces microleakage and discoloration of the esthetic restoration, extending its service-life.

• Asian-Australasian Journal of Animal Sciences
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• 제23권8호
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• pp.1105-1111
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• 2010

In order to determine the potential for reduction of nitrite levels and ripening period with heat treatment, the effects of ripening period (1-13 days), nitrite level (45-195 ppm), and heat treatment (30-$90^{\circ}C$) on lipolysis, peroxide, TBA, proteolysis, and residual nitrite values of sucuk were investigated using response surface methodology. The ripening period significantly (p<0.01) increased lipolysis, peroxide, TBA, and proteolysis values and decreased residual nitrite values. The effects of additional nitrite levels were found to significantly affect peroxide and residual nitrite values. Significant amounts of the additional nitrite levels were reduced during processing and on the first day of ripening periods.

• Restorative Dentistry and Endodontics
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• 제26권5호
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• pp.399-408
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• 2001

Tooth bleaching has been prevailing recently for its ability to recover the color and shape of natural teeth without reduction of tooth material. However, it has been reported that bleaching procedure adversely affects the adhesive bond strength of composite resin to tooth. At the same time the bond strength was reported to be regained by application of some chemical agents. The purpose of this in vitro study was to investigate the effect of the removal of residual peroxide on the composite- enamel adhesion and also evaluated fracture mode between resin and enamel after bleaching. Sixty extracted human anterior and premolars teeth were divided into 5 groups and bleached by combined technique using of office bleaching with 35 % hydrogen peroxide and matrix bleaching with 10% carbamide peroxide for 4 weeks. After bleaching, the labial surfaces of each tooth were treated with catalase, 70% ethyl alcohol, distilled water and filled with composite resin. Shear bond strength was tested and the fractured surfaces were also examined with SEM. Analysis revealed significantly higher bond strength values. (p＜0.05) for catalase-treated specimens, but water-treated specimens showed reduction of bond strength, alcohol- treated specimens had medium value between the two groups(p＜0.05). The fracture mode was shown that the catalase group and the alcohol group had cohesive failure but the water sprayed group had adhesive failure. It was concluded that the peroxide residues in tooth after bleaching seems to be removed by gradual diffusion and the free radical oxygen from peroxide prevents polymerization by combining catalyst in the resin monomer. Therefore it may be possible to eliminate the adverse effect on the adhesion of composite resin to enamel after bleaching by using water displacement solution or dentin bonding agent including it for effective removal of residual peroxide.

• 상하수도학회지
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• 제23권4호
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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 $H_2O_2/L$.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2001년도 추계학술발표회
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• pp.51-54
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• 2001

This research was carried out to evaluate feasibility of using an Electrokinetic-Fenton(EK-Fenton) technique to treat hydrophobic organic pollutant(phenanthrene) from soils. Experiment examined the effect by introducing a continuous flow of a 3.5% hydrogen peroxide solution at the anode. An electric gradient of 1V/cm was applied to enhance the saturated flow in the soil cell for a period of 11 days. After 11 days or 1 pore volume, overall concentration of residual phenanthrene in the soil cell was 11% and residual phenanathrene concentration in the soil was found to increase with toward the cathode. This results indicated that Fenton-like reaction catalyzed by mineral surface was effective in oxidizing phenanthrene. This results also showed that hydrogen peroxide was effectively transported into the soil by electroosmotic flow as well as by diffusion.

• 한국물환경학회지
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• 제28권5호
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• pp.704-716
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• 2012

본 논문은 California의 South Lake Tahoe, 서울 뚝섬정수장 그리고 성남 복정정수장에서 2010년 2월에서 2012년 2월까지 수행된 파일럿 실험에 대한 분석결과를 기초로 작성되었다. 본 실험의 목적은 첫째, 한강을 원수로 하는 모래여과 처리수에 대한 오존 및 과산화수소(Peroxone)의 반응특성을 파악하고, 둘째는 AOP(고도산화공정)을 통해 맛 냄새 유발물질인 2-methylisoborneol(MIB)를 제거하기위한 경험적인 오존 및 과산화수소의 투입량을 결정하고자 하였다. 또한 셋째로, 처리공정이후 인체에 안전한 잔류오존농도로 감소시키기 위한 최적 투입량을 결정하고자 하였다. 본 실험은 계절의 기온변화에 따라 저수온 및 고수온의 조건하에서 실시간으로 수행되었다. 본 실험을 통해 오존의 분해속도는 온도와 pH에 영향을 받는 것으로 나타났으며, 이는 다른 연구결과와 일치한다. 원수로 모래여과수에 MIB를 40~50ng/L의 농도로 투입하였으며, 모든 경우에서 7ng/L 이하로 처리되었으며 대부분의 경우에서 검출(ND)되지 않았다. Peroxone은 MIB을 제거할 뿐아니라 오존을 단독으로 사용한 경우보다 오존+과산화수소 동시에 투입한 경우에 잔류오존농도가 더 낮았다. 저수온에서 상당량의 오존이 반응 및 분해를 통해 감소된다. 본 실험을 통해 "Pre-Conditioned" 과산화수소를 적용함으로써 초기 반응율을 향상시키고 잔류오존농도를 낮출 수 있었으며, 약품의 과투입 및 효율저하를 방지하는 과산화수소의 투입 위치 및 구성 그리고 투입방법을 제시하였다.

• 공업화학
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• 제9권5호
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• pp.754-757
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• 1998

본 연구는 탈묵펄프 공정의 과산화수소 보존표백시 과산화수소 안정제 Versenate PS에 의한 silicate 대체효과를 검토하였다. 대체 가능성을 파악하기 위하여 silicate 및 Versenate PS 처리 표백시 전처리와 가성소다의 최적화 실험을 시행한 후 잔류 과산화수소의 함량과 백색도를 측정하였다. 얻은 결과를 요약하면 다음과 같다. 1. Silicate 처리 표백시 가성소다의 최적농도는 2.5~3.0%였다. 2. Versenate PS처리 표백시 가성소다의 최적농도는 1.0~1.5%였다. 3. Versenate PS 단독 처리만으로는 만족할 만한 표백효과를 나타내지 못했다. 4. Versenate PS 처리 표백시에는 silicate양을 상당량 줄일 수 있다. 5. DTPA로 전처리 하는 것이 좀 더 높은 표백효율을 나타내었다.

• 한국환경과학회지
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• 제16권12호
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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.

• 상하수도학회지
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• 제29권4호
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• pp.481-491
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• 2015

The aim of this study was to evaluate the chemical quenching system for residual ozone and to determine the operating condition for the quenching system. Hydrogen peroxide ($H_2O_2$) and sodium thiosulfate ($Na_2S_2O_3$) were investigated as quenching reagents for ozone removal, and the tendency of each chemical was notably different. In the case of $H_2O_2$, the degradation rate of ozone was increased as the concentration of $H_2O_2$ increase, and temperature and pH value have a significant effect on the degradation rate of ozone. On the other hand, the degradation rate of ozone was not affected by the concentration of $Na_2S_2O_3$, temperature and pH value, due to the high reactivity between the ${S_2O_3}^{2-}$ and ozone. This study evaluates the decomposition mechanism of ozone by $H_2O_2$ and $Na_2S_2O_3$ with consideration for the water quality and reaction time. Furthermore, the removal test for the quenching reagents, which can be remained after reaction with ozone, was conducted by GAC process.

• 상하수도학회지
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• 제18권3호
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• pp.377-384
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• 2004

In the present study, a feasibility of an advanced oxidation process using UV/Hydrogen peroxide($H_2O_2$) system equipped with a medium pressure lamp for secondary effluent reclamation was investigated. Initial concentration of $H_2O_2$ and pH were changed to determine the optimum operation condition for the system. The removal efficiency of color was than 80% with 14.3mg/L of initial $H_2O_2$ and 5 minute of contact time in the UV/$H_2O_2$ system. The color removal was analyzed using first-order reaction equation. The dependence of rate constant (k) on initial $H_2O_2$ represented the rational relationship with maximum value. Residual $H_2O_2$ caused increase of effluent COD, since analyzing agent, dichromate, reacted with $H_2O_2$ in the sample. Therefore, excess initial concentration of $H_2O_2$ would significantly affect effluent COD measurement. At pH variation experiment, both residual $H_2O_2$ and color showed peak in the neutral pH range with the same pattern. Effect of $H_2O_2$ dose also enhanced color removal but raised residual $H_2O_2$ problem in the continuous operation UV system. In conclusion, these results indicated that medium pressure UV/$H_2O_2$ system could be used to control color in the secondary effluent for reclamation and reuse.