• Journal of Advanced Marine Engineering and Technology
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• 제31권6호
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• pp.694-698
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• 2007

This present study has dealt with the effect of surfactant on the freezing of aqueous solution Sodium chloride aqueous solution was used to measure the effect of surfactant and the main parameters of this experiment were temperature of bath, revolution of stirrer. and the radial velocity of NaCl solution. The acquired main conclusions are as follows; 1) the lower super-cooling temperature make hardly to attach the ice on beaker, 2) the size of ice become smaller to add the surfactant, 3) the ice packing factor increase with increasing of stirrer revolution.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
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• pp.315-317
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• 2004

Henry's law constants of trichloroethylene (TCE) and tetrachloroethylene (PCE) in air-aqueous surfactant systems were determined by gas chromatography headspace analysis of closed system. The effect of surfactant type and concentration was investigated.

• 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.

• Bulletin of the Korean Chemical Society
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• 제18권3호
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• pp.300-305
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• 1997

Effect of a nonionic surfactant, Tween 20 on the adsorption and kinetic mechanism for the hydrolysis of a microcrystalline cellulose, Avicel PH 101, by endoglucanase Ⅰ (Endo Ⅰ) and exoglucanase Ⅱ (Exo Ⅱ) isolated from Trichoderma viride were studied. The Langmuir isotherm parameters, amount of maximum adsorption (Amax) and adsorption equilibrium constant (Kad) for the adsorption, were obtained in the presence and the absence of nonionic surfactant. On the addition of Tween 20, the Kad and Amax values of Exo Ⅱ were decreased, while those of Endo Ⅰ were not affected. These indicate that the adsorption affinity of Exo Ⅱ on the cellulose is weakened by nonionic surfactant, and the surfactant enhanced desorption of Exo Ⅱ from insoluble substrate. The enzymatic hydrolysis of the cellulose can be described by two parallel pseudo-first order reactions using the percentages of easily (Ca) and hardly (Cb) hydrolyzable cellulose in Avicel PH 101 and associated rate constants (ka and kb). The Ca value was increased by adding Tween 20 for all enzyme samples (Exo Ⅱ, Endo Ⅰ and their 1:1 mixture) implying that the low-ordered crystalline fraction in the cellulose may be partly dispersed by surfactant. The ka value was not affect by adding Tween 20 for all enzyme samples (Exo Ⅱ, Endo Ⅰ and their 1:1 mixture). The kb value of Exo Ⅱ was increased by adding Tween 20, while that of Endo Ⅰ was not affected. This suggests that the surfactant helps the Exo Ⅱ desorb from microcrystalline cellulose, and increase the hydrolysis rate. These results were show that the increase of hydrolysis of cellulose by the nonionic surfactant is due to both the activation of Exo Ⅱ and partial defibrillation of the cellulose.

• 전기화학회지
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• 제24권3호
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• pp.35-41
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• 2021

본 연구에서는, 양쪽이온성 계면활성제가 구리전해도금에 미치는 영향을 cyclic voltammetry를 이용해 분석해보았다. 대표적인 양쪽이온성 계면활성제인(dodecyldimethylammonio)propanesulfonate (DDAPS)를 전해도금액에 첨가할 경우, Cu²⁺의 환원반응이 억제되는 것을 확인할 수 있었으며, 이러한 억제 효과는 음이온성 계면활성제가 아닌 양이온성 계면활성제와 유사한 특성에 해당한다. 뿐만 아니라, DDAPS는 염소이온과 상호작용을 나타내었고, 억제효과가 물질전달 조건에 따라 변화하는 특성을 가지고 있었으며, 구리도금막의 거칠기 또한 미약하게 감소시켰다. 이러한 특성은, 양이온성 계면활성제의 특성과 유사하나 다소 약화된 모습이었으며, 이를 통해 DDAPS의 작용은 양전하의 친수성 머리에 의해 주도되며, 이 양전하는 음전하 친수성 머리에 의해 shielding 되어 있음을 확인할 수 있었다.

• Applied Biological Chemistry
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• 제47권1호
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• pp.72-77
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• 2004

5% corn oil과 17 mM Brji 700으로 제조한 oil-in-water emulsion(O/W)에서 과량의 잉여 surfactant가 phenol이 첨가된 O/W의 산화에 미치는 영향을 알아보기 위하여 Brji 700을 $0{\sim}2%$의 농도로 O/W에 첨가한 경우, 첨가된 surfactant의 양이 증가할수록 droplet의 particle size는 커지는 경향을 나타내었다. 또한 continuous phase의 surfactant 농도도 높아지며 phenol 함량도 상대적으로 높아지는 것을 알 수 있었다. Phenol류가 100 ppm의 농도로 첨가된 O/W에 과량의 surfactant$(0{\sim}2%)$를 첨가하고 30일간 저장 기간별 hydroperoxide의 생성량을 측정한 결과, 대조구에 비해 낮은 hydroperoxide 함량을 보여 surfactant를 첨가하지 않은 실험구와 유사한 경향을 보였으나, hydroperoxide 함량은 surfactant를 추가하지 않은 실험구 보다 더 낮은 값을 나타내었다. 또한 phenol 종류 및 surfactant 농도별 hydroperoxide 생성억제 효과와 headspace aldehyde 생성 억제 효과는 BHT>procyanidin B3-3-O-gallate>(+)-gallocatechin>(+)-catechin 및 2%>1%>0% surfactant 첨가의 순서로 나타났다. 이러한 결과는 phenol성 물질과 과량의 surfactant micelle에 의해 emulsion으로부터 continuous phase로 hydroperoxide의 physical location 변화가 발생하는 것을 나타낸다.

• 한국의류학회지
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• 제23권7호
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• pp.1030-1039
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• 1999

The effect of surfactant mixture 9on detergency and soil redeposition in a dry-cleaning system was investigated employing Aerosol OT as an anionic surfactant and Span 80 as a nonionic surfactant. The effect of charge system on soil deposition was also investigated in order to determine the optimum condition at which soil redeposition is minimum,. Soil deposition instead of soil redeposition on cotton, polyester and wool fabrics was measured employing petroleum solvent and perchloroethylene as organic solvents. The results were as follows. 1. Surface tension or interfacial tension was not changed by the addition of any surfactant or surfactant mixtures. In petroleum solvent however interfacial tension between solrent and water decreased when surfactants were added and increased when surfactants were mixed,. 2. The maximum amount of water solubilization increased as the mole fraction of Aerosol OT increased and more water was solubilized in petroleum solvent than in perchloroethylene. 3. The detergency of cotton was greater and the soil deposition rate was lower in Span 80 solution than in Aerosol OT solution. The soil deposition on cotton fabric decreased when water was solubilized in Aersol OT solution 4. The detergency and soil deposition rate of polyester fabric did not change by the surfactant type of the addition of surfactant mixture and soil deposition rate increased bywater solubilization. 5. Soil deposition on wool fabric was very high when Arosol OT was employed in perchloroethylene and the soil deposition did not change greatly by water solubilization.

• 한국지하수토양환경학회지:지하수토양환경
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• 제12권6호
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• pp.38-45
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• 2007

트리클로로에틸렌(trichloroethyele, TCE)는 지하 환경으로 누출되었을 경우 대표적인 고밀도 불용성 유체(dense non aqueous phase liquids, DNAPLs)를 형성하여 토양과 지하수를 오염시키며, 계면활성제를 이용한 SEAR(Surfactant-enhanced aquifer remediation) 공법으로 처리를 하여도 소량이 계면활성제와 함께 지하수에 존재한다. 본 연구에서는 SEAR공법으로 처리 후 잔존하는 TCE가 계면활성제와 함께 존재할 때, 영가철(zero valent iron, ZVI)로 이루어진 투수성 반응벽체(PRB)에서의 TCE 거동을 조사하였다. 특히 계면활성제의 독성과 반응속도의 영향을 고려하여 양이온과 비이온 혼합 계면활성제의 영향을 중점적으로 다루었다. 혼합 계면활성제를 사용할 경우 ZVI를 이용한 TCE의 분해는 계면활성제의 구조에 따라 상당히 다른 경향을 보였다. TCE의 제거율을 살펴보면 비이온 계면활성제의 친수성기인 polyoxyethylene(POE) 사슬이 짧을 경우 양이온 계면활성제와 상관없이 거의 일정하였고, 상대적으로 긴 POE사슬일 경우 양이온 계면활성제의 종류와 첨가량에 따라 차이가 발생하였다. 친수성기가 트리메틸암모늄 (trimethylammonium)인 양이온 계면활성제가 피리디늄(pyridinium)를 가지는 양이온 계면활성제보다 더 높은 TCE 제거율을 보였다. 이러한 연구결과는 SEAR 후처리를 위해 PRB 적용시 잔존하는 계면활성제의 영향을 살펴보았으며 실제 현장적용의 중요한 자료로 이용될 수 있을 것으로 사료된다.

• 한국환경과학회지
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• 제9권5호
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• pp.365-368
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• 2000

The antibacterial effect amino acid-copper(II) surfactant on fish pathogens was studied. Fish pathogens of Edwardsiella tarda Vibrio anguillarum Aeromonas hydrophila and Streptococcus sp. were selected cultured in nutrient agar and adjusted at $2{\times}10^5~10^6 CFU/$m\ell$$ in phosphate buffer saline before the addtion of amino acid-copper(II) surfactant with different concentrations. All tested pathogens died within 1 hour with 1 ppm of amino acid-copper(II) surfactant. In comparison with formalin and ET. amino acid-copper (II) surfactnat was more effective in antibacterial capacity.

• Journal of Advanced Marine Engineering and Technology
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• 제31권5호
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• pp.552-557
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• 2007

This paper has dealt with the effect of non ionized surfactant and water mixture on drag reduction and heat transfer enhancement in a circular pipe flow with experimentally. The test section was consisted of stainless steel pipe with inside diameter of 16mm. The wire coil was used to increase heat transfer in a pipe and the on ionized surfactant(Oleyl Dihydroxyethyl Amino Oxide, ODEAO) was used to reduce the drag force of water mixture with surfactant. The main parameters of this experiment were diameter and pitch of wire coil and the ratio of test section length and horizontal wire coil length. In this experiment, the acquired results were 1) Drag reduction effect existed in this ODEAO-water mixture, 2) Friction factor and heat transfer were increased with insertion the heat transfer enhancement coil, 3) With increasing of pitch ratio, heat transfer was decreased, and 4) Heat transfer was decreased by the decreasing of inserting coil diameter.