• 한국식품과학회지
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• 제30권5호
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• pp.1040-1044
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• 1998

피로인산나트륨(tetrasodium pyrophosphate)을 과산화수소수에 용해시켜 결정화하면 과산화수소가 피로인산나트륨에 안정하게 결합된 과산화피로인산나트륨(tetrasodium pyrophosphate peroxidate)이 만들어지게 된다. 이 화합물의 식품보존제로서의 사용 가능성을 알아보기 위하여 항균력과 안정성에 대하여 검토해 보았다. 이 화합물은 0.1% (w/v)의 농도에서 항균력을 가지고 있는 것으로 나타났고 그 수용액은 상온에서 80일간 방치하여 과산화수소가 결합된 상태의 과산화피로인산나트륨이 70% 수준으로 잔류하는 안정한 상태로 존재하고 있는 것으로 나타났다. 또한 열에도 상당히 안정하여 60분간의 중탕처리에 의해서도 과산화피로인산나트륨이 76% 수준으로 존재하는 것으로 나타났다. 그러나 금속이온에 의해서는 상당한 영향을 받는 것으로 나타났다. 식품보존제로 이 화합물을 0.2% (w/v) 사용할 경우 0.03% (v/v)의 과산화수소가 존재하는 것으로 측정되었다. 적용범위, 사용방법 및 과산화수소의 제거법이 개발된다면 장래 식품보존제로 사용될 수 있을 것이다.

• Bulletin of the Korean Chemical Society
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• 제32권spc8호
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• pp.2933-2937
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• 2011

A new highly selective receptor (3) based on an acridine-imidazolium functionalized cholestane for anion sensing was designed and synthesized. A binding study of 3 with various anions was assessed by UV-vis and fluorescence spectroscopies in dry CH3CN. Receptor 3 showed the highest selectivity toward hydrogen pyrophosphate (Ka = $1.5{\times}10^4M^{-1}$).

• 한국물환경학회지
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• 제30권6호
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• pp.653-657
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• 2014

Effects of $H_2O_2$ addition for fenton oxidation on iron coagulation for treatment of phosphorus species, such as orthophosphate, metaphosphate, pyrophosphate, organic phosphate, were investigated. The effects of coagulant dosage, hydrogen peroxide dosage and the combined sequence ferric coagulation and $H_2O_2$ addition for fenton oxidation and coagulation were studied. The characteristics of floc growth rate were monitored using the PDA. The removal efficiencies of phosphorus species by iron coagulation were increased as Fe/P molar ratio increased. However, the removal efficiencies of metaphosphate, pyrophosphate, organic phosphate by a ferric coagulation were not increased as Fe/P molar ratio increased. The removal efficiency of metaphosphate, pyrophosphate, organic phosphate was increased by using iron coagulation and $H_2O_2$ addition for fenton oxidation. The result indicated that non-reactive phosphorus after iron coagulation was changed to reactive phosphorus by $H_2O_2$ addition for fenton oxidation and the oxidized iron enhanced the coagulation efficiencies.

• 한국의류학회지
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• 제29권9_10호
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• pp.1295-1305
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• 2005

The study was based on a three-stage, non-repetitive factorial experiment in which chemical-rotted kenaf fibers were treated separately with hydrogen peroxide concentrations of $0.5\%,\;1\%\;and\;2\%$, with pH solutions of 7, 9 and 11, and treatment times of 30, 60 and 90 minutes. Under optimal conditions, the study was conducted to determine the bleaching efficiency by the addition of chelators, penetrants and surfactants. The bleaching effects on the kenaf fibers were high in high hydrogen peroxide concentration, high in alkali solution pH, low in long treatment time. The optimal level of hydrogen peroxide on bleaching effects were at $2\%$ hydrogen peroxide concentration, with pH of 11 and treatment time of 60 minutes. Under the conditions of $2\%$ hydrogen peroxide concentration, pH 11 and treatment time of 60 minutes, the addition of chelator: Sodim Pyrophosphate(SP), Citric Acid(CA) made the bleaching effects of the kenaf fibers high.

• 한국세라믹학회지
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• 제51권4호
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• pp.248-259
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• 2014

Acceptor-doped cerium pyrophosphates have shown significant proton conductivity of > $10^{-2}Scm^{-1}$ in the range of $100-300^{\circ}C$ and are considered promising candidates for use as electrolytes in proton-conducting, ceramic electrolyte fuel cells (PCFCs). But, cerium pyrophosphates themselves do not have structural protons, and protons incorporate into their material bulk only as impurities on exposure to a hydrogen-containing atmosphere. However, proton incorporation and proton conduction in these materials are expected to be affected by factors such as the nature (ionic size and charge) and concentration of the aliovalent dopant, processing history (synthesis route and microstructure), and the presence of residual phosphorous phosphate ($P_mO_n$) phases. An exact understanding of these aspects has not yet been achieved, leading to large differences in the magnitude of proton conductivity of cerium pyrophosphates reported in various studies. Herein, we systematically address some of these aspects, and present an overview of factors affecting proton conductivity inacceptor-doped $CeP_2O_7$.

• 한국치위생학회지
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• 제15권2호
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• pp.325-332
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• 2015

Objectives: The purpose of this study was to investigate tooth whitening maintenance efficacy of several dentifrices containing effective ingredients for tooth whitening. Methods: Hydroxyapatite specimens(HAPs) staining was done by using modified Stookey's methods. HAPs were treated with 2.9% hydrogen peroxide containing strip for whitening, and were shaken with several dentifrice slurry(dentifrice 1 : artificial saliva 2) for 30 minutes. The HAPs were finally dipped in staining solution for an hour. Shaking and dipping were repeated 4 times and lightness values were measured by colorimeter at each step. In clinical test, test 4 dentifrice and control dentifrice were evaluated by 21 subjects for 2 months after receiving institutional review board(IRB) approval. Organoleptic(vita shade guide) and instrumental(SHADEEYE-NCC) evaluation were performed for whiteness change of teeth. Statistical analysis was performed using repeated measures ANOVA, Tukey's post hoc test and ${\chi}^2$-test(p<0.05). Results: All dentifrices showed statistical significance in comparison with control dentifrice containing sodium fluoride and test 4 dentifrice containing sodium pyrophosphate, sodium metaphosphate, candelilla wax, and sodium fluoride showed statistical significance in comparison with other dentifrices by inhibiting staining in vitro(p<0.05). In clinical test, test 4 dentifrice showed better effects than control dentifrice in organoleptic and instrumental evaluation in tooth whitening maintenance efficacy(p<0.05). The awareness toward tooth whitening maintenance efficacy for 2 months use showed that test 4 dentifrice was much better than control dentifrice, but did not show statistically significant(p>0.05). Conclusions: Dentifrice containing sodium pyrophosphate, sodium metaphosphate, candelilla wax and sodium fluoride was more effective in keeping teeth white.

• 한국치위생학회지
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• 제14권1호
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• pp.101-108
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• 2014

Objectives : The purpose of this study was to evaluate the tooth whitening effect of 0.74% and 2.80% hydrogen peroxide toothpastes and safety on tooth and gingival tissue. Methods : Toothpastes containing 0.74% and 2.80% hydrogen peroxide were evaluated. In in-vitro test, some additives (sodium metaphosphate, sodium pyrophosphate and titanium dioxide) were added to the toothpastes. Hydroxyapatite specimens (HAPs) were made and stained using modified Stookey's methods. HAPs were treated for 1 hour at shaking incubator and brushed for 1,000 times as 250 gF with each diluted toothpaste. Before and after color was measured by colorimeter. Using double blind method, 99 Korean with natural maxillary anterior teeth were selected and the initial brightness (baseline) was measured by SHADEEYE-EX. Based on this measurement they were crossly distributed into control group (0% hydrogen peroxide), test 1 (0.74% hydrogen peroxide) and test 2 (2.80% hydrogen peroxide). After 2 weeks, people of each group were provided toothpaste and told to use 3 times a day right after every meal for 3 minutes. The brightness of teeth was measured 3 times for every one month. Results : ${\Delta}L$ was statistically significant among three groups in shaking test. ${\Delta}L$ of two test groups was statistically significant compared with control group but not between each test group in brushing test. After using toothpaste for 3 months, test 1 group and test 2 group were 15.89% and 31.23% more whitened compared with control group respectively (p<0.05). Rate of more whitened person of each test group was 24.2% and 40.5% more than control group respectively (p<0.05). There was no difference in the hypersensitivity during 3 months using toothpastes and no side effect on teeth or gums. Conclusions : Toothpastes containing 0.74% and 2.80% hydrogen peroxide showed tooth whitening effect and both were safe enough to use for tooth whitening.

• 치위생과학회지
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• 제16권2호
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• pp.176-182
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• 2016

페이스트 치약의 구강 내 사용시간(1~3분)과 사용시간을 길게 조절할 수 있는 부착형 치약의 사용시간을 고려하여 치약제의 유효성분을 처리시간 조건별로(1분, 3분, 10분, 30분 및 60분) 미백 효과, 항치석 효과, 재광화 효과 및 상아세관의 폐쇄 효과를 실험실적으로 평가한 결과 다음과 같은 결과를 도출하였다. 처리 시간대별 명도 변화값(${\Delta}L$)은 1분 $5.50{\pm}1.51$에서 60분 $27.35{\pm}0.54$였고 치석으로부터 제거된 칼슘 양(ppm)은 1분 $4.23{\pm}0.14$에서 60분 $25.15{\pm}0.32$였으며 경도 증가값은 1분 $1.96{\pm}1.44$에서 60분 $12.55{\pm}2.09$였다. 상아세관의 폐쇄 정도는 10분 처리에서 일부 상아세관의 폐쇄가 관찰되기 시작하여 60분 처리에서는 대부분의 상아세관의 폐쇄가 관찰되었다. 본 실험조건에서는 처리시간을 10분에서 60분 처리시 1분에서 3분 처리할 때보다 최소 1.57배에서 최대 8.26배까지 효능을 증가시켰으며 재광화 효과, 항치석 효과 및 상아세관 폐쇄 효과에서는 사용시간 10분 이상에서 적절하였고 미백효과에서는 30분 이상이 보다 효과적일 것으로 생각되었다.