• 한국응용과학기술학회지
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• 제31권3호
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• pp.478-485
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• 2014

이 연구는 경표피흡수를 위하여 큐빅액정의 자기조직체의 형성에 관한 것이다. 복수 수산기(-OH)를 가지는 친수부에 4개의 메칠 그룹을 가지는 양친매성지질인 diglyceryl phytylacetate (DGPA)를 합성하여 다양한 성능평가를 수행하였다. DGPA의 유화력은 1%의 적은 농도에서도 고 내상의 물을 함유하는 안정한 W/O water-in-oil)에멀젼이 유지되었다. DGPA, dimethicone (2CS), water의 3성분계의 특정영역에서, 안정한 큐빅상의 액정이 형성되었다. 3상 구조도 작성을 통하여 큐빅 액정영역, 헥사고날 영역, 물과 헥사고날이 혼제된 영역, 역미셀 영역을 확인하였고, SAXS (small angled x-ray scattering)분석을 통하여 그 구조를 증명하였다. 화장품의 응용으로, 큐보좀 (cubosome)에 10%의 마그네슘아스코르빌포스페이트, 5％의 피리독신트리헥사데카노에이트를 봉입하여 캡슐화하였다. 큐보좀의 occlusive 효과는 역미셀(reverse micelle)보다 1.7배 우수한 효과를 가졌다. 큐보좀을 분산제인 poloxamer를 사용하여 W/O 에멀젼을 만든 것으로부터 큐빅구조의 액정상으로 회복되는 것을 새롭게 발견하였다. 따라서, DGPA의 양친매성지질의 특성을 이용하여, 큐빅상의 액정을 형성하는 기재로써 화장품 산업과 의약품분야에서 경표피흡수제로써 응용이 가능할 것으로 기대된다.

• 한국응용과학기술학회지
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• 제26권4호
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• pp.422-427
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• 2009

We have investigated the effects of polyols and NaCl on the rheological behaviours of surfactant mixtures. Sodium lauryl ether sulfate (SLES), cocamidopropyl betaine (CAPB), disodium cocoamphodiacetate (DSCA), cocamide DEA (CDEA) and lauroyl/myristoyl DEA (LMDE) were used as surfactants. The polyols added into the surfactant mixture were 1,3-butylene glycol, propylene glycol, glycerin, sorbitol, dipropylene glycol, PEG 1500 and PEG 400. The addition of amphoteric surfactant to SLES aqueous solution lead to increase the height of foam and the viscosity of the system. The addition of nonionic surfactant, LMDE or CDEA to the SLES aqueous solution increased the viscosity and the effect of LMDE was better than that of CDEA. The effect of adding polyols and NaCl into the surfactant mixture aqueous solution lead to increase or decrease the viscosity of the systems depending on the concentration of NaCl and the kinds of polyols. These results can be explained through the salting in or salting out of surfactant of the systems.

• 한국조리학회지
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• 제24권2호
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• pp.103-111
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• 2018

The objectives of the present study were to examine the antioxidant activity of autofocusing fractions from egg white protein hydrolysates and obtain higher antioxidant peptide fraction, which could be applied to the food model system. Alkaline protease hydrolysate of egg white protein exerted higher antioxidant activities than other protein hydrolysates and were fractionated on the basis of the amphoteric nature of sample peptides by preparative isoelectric focusing without toxic solvents and reagents, which is termed autofocusing. Neutral and basic fractions showed higher 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity than the acidic fractions. The acidic and neutral fractions showed higher hydroxyl (OH) radical scavenging activity and oxygen radical absorbance capacity (ORAC) values than the basic fractions. The acidic fractions showed higher metal chelating activity than basic fractions. Antioxidant activities of some autofocusing fractions except for ORAC showed higher compared to the crude hydrolysate. These results suggest that peptides fractions from egg white protein are effective antioxidant, and that autofocusing could be useful to increase antioxidant activity for application to food system.

• Bulletin of the Korean Chemical Society
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• 제24권2호
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• pp.173-177
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• 2003

The present work is focused on the preconcentration of nickel and its determination by means of diffuse reflection spectroscopy. The preconcentration of nickel was carried out by sorption on macroporous aminocarboxylic amphoteric resin ANKB-35. Based on this collector, a method to determine nickel in wastes of heat power industry was worked out using solid-phase spectroscopy. The colored surface compound to be determined was obtained by a preceding nickel sorption on the resin and by subsequent treatment of the concentrate obtained with definite amounts of 1-(2-pyridilazo)-2-naphtol (PAN). The Ni calibration curve is linear in the concentration range of 0.5-20.0 mg/L (sample volume is 200.0 mL) and the detection limit is 0.05 mg/L. The presence of $Cu^{2+},\;Fe^{3+},\;Co^{2+}$ ions as well as macrocomponents of natural water $(Na^+,\;K^+,\;Ca^{2+},\;Mg^{2+})$ do not hinder the solid-phase spectroscopy determination of nickel. The nickel determination by diffuse reflection spectroscopy was carried out in model solutions as well as in solutions obtained after the dissolution of wastes of heat power industry.

• Advances in environmental research
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• 제5권2호
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• pp.141-151
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• 2016

Large amounts of aluminum hydroxide ($Al(OH)_3$) exist in water purification sludge (WPS) because of the added aluminum coagulant in water treatment process. Notably, $Al(OH)_3$ is an amphoteric compound, can be dissolved in its basic condition using sodium hydroxide to form aluminate ions ($Al(OH)_4{^-}$). However, in a process in which pH is increasing, the humid acid can be dissolved easily from WPS and will inhibit the recovery and reuse of the dissolved aluminate ions. This study attempts to fix this problem by a novel approach to separate $Al(OH)_4{^-}$ ions using nanofiltration (NF) technology. Sludge impurity in a alkaline solution is retained by the NF membrane, such that the process recovers $Al(OH)_4{^-}$ ions, and significantly decreases the organic matter or heavy metal impurities in the permeate solution. The $Al(OH)_4{^-}$ ion is an alkaline substance. Experimental results confirm that a recovered coagulant of $Al(OH)_4{^-}$ ion can effectively remove kaolin particles from slightly acidic synthetic raw water.

• 한국응용과학기술학회지
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• 제3권1호
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• pp.65-71
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• 1986

Four amphoteric surfactants, 1-(N-alkyl-N,N-dimethyl ammonio)-4-naphthalene sulfonates, were prepared by the alkylation of 1-(N,N-dimethylamino)-4,naphthalene sulfonic acid with chloroalkanes such as 1-decylchloride, 1-tetradecyl chloride and 1-hexadecyl chloride. These quaternary ammonium compounds such as 1-(N-decyl-N, N-dimethylammonio)-4-naphthalene sulfonate, 1-(N-dodecyl-N,N-dimethylammonio)-4-naphthalene sulfonate, 1-(N-tetradecyl-N,N-dimethylammonio)-4-naphthalene sulfonate and 1-(N-hexadecyl-N,N-dimethylammonio)-4-naphthalene sulfonate could be separated by means of thin layes chromatography and column chromatography. The surface chemical properties such as surface tension, foaming power, foam stability, wetting efficiency and solubilizing effect for these four compounds were measured. Also critical micelle concentration and hydrophilic-lipophilic balance(HLB) were evaluated. These compounds showed good surface as O/W type emulsifying agent and detergent.

• 한국수산과학회지
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• 제43권6호
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• pp.606-613
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• 2010

In order to elucidate a mechanism responsible for the development of the odor characteristics of cooked, desirable-flavored shellfish, oysters were extracted using various solvents and the resulting extracts were evaluated organoleptically after cooking. The 80% aqueous methanol extract was found to produce a desirable cooked flavor. This oyster extract was fractionated using ion-exchange column chromatography and dialysis, and each of the fractions was subjected to cooking, followed by organoleptic evaluation. The outer dialysate fraction such as acidic and amphoteric water-soluble fractions produced a cooked oyster flavor. The volatile flavor compounds identified from cooked oyster included 29 hydrocarbons, 20 alcohols, 16 acids, 12 aldehydes, nine nitrogen-containing aromatic compounds, eight ketones, five furans, three esters, three phenols, and one benzene.

• 한국막학회:학술대회논문집
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• 한국막학회 1998년도 춘계 총회 및 학술발표회
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• pp.97-98
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• 1998

1. Introduction : Polypropylene(PP) membrane is widely used in the field of microfiltration and ultrafiltration. However, the hydrophobicity of PP causes the adsorption of hydrophobic and amphoteric solutes in the feed. Surface modification techniques of membrane through the treatment of hydrophilizing agents, coating of hydrophilic compounds, UV, plasma and high energy irradiation, etc. can have a great effect on propensities to prevent the protein from staining membranes. Among them, the modification to hydophilize membrane surface using UV is very simple and effective. Recently many studies for more effective surface modification have been conducted. Iwata et al. prepared membranes by grafting polyethylene glycol diacrylate macromer(PEGDA) onto polysulfone with plasma using a glow discharge reactor which prevent the oil from staining the membrane. The primary mechanism contributing to the membranes is preventing the oil from directly contacting the surface of the membrane as the PEGDA chains dissolved into emulsion. To evaluate their feasibility for use as a anti-fouling separation membrane, we prepared hydrophilic membranes by UV irradiation method and investigated their characteristics.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.1098-1108
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• 2008

Batch type and column type experiments were performed in order to predict adsorption and movement within soil. Clay minerals montmorillonite and kaolinite were respectively added to paraquat which is a cationic compound with long residual time, 2,4-D which is an anionic compound with relatively short residual time and napropamide which is an amphoteric compound. Therefore, it is very important to determine the movements of toxic pollutants in the ground soil to establish measures to prevent soil grounds contamination and to restore contaminated soils effectively, because contamination of soil is getting severe due to these toxic wastes, industrial waste water, and agricultural chemicals, etc. Therefore, in this study, we have carried out column and batch experiments by using general toxic organic compounds as test samples in order to restore contaminated soils effectively as well as to prepare a basic data to develop absorbents that will remove various toxic organic compounds, with a grandiose purpose to prevent contaminations of soil and grounds due to various toxic organic compounds.

• 한국환경과학회지
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• 제28권8호
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• pp.689-700
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• 2019

The adsorption and leaching characteristics of five ionic pesticides including four acidic pesticides (2,4-D, dicamba, MCPA, and MCPP) and one amphoteric pesticide (imazaquin) in agricultural soils were investigated. Soils around spring waters that were heavily affected by pesticide run-off and soils around wells considering the regional characteristics in Jeju Island were collected at 24 stations. The Freundlich constant, $K_F$ value, which is a measure of the adsorption capacity, decreased in the order of 2,4-D > MCPA > MCPP > dicamba > imazaquin. The adsorption capacity of these ionic pesticides decreased with increasing pH owing to the effects of ionization of pesticides and different ionizable functional groups of soils. The leaching of ionic pesticides in the soil column showed a reverse relationship with their adsorption in soils, namely, the ionic pesticides were leached more quickly for the pesticides with lower adsorption capacity. The groundwater contamination potential of the ionic pesticides was evaluated in the order of imazaquin > MCPA > MCPP > dicamba > 2.4-D according to the groundwater ubiquity score based on soil Koc and the half-life of the pesticide.