• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2000년도 추계학술대회 논문집(Proceeding of the KOSME 2000 Autumn Annual Meeting)
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• pp.91-98
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• 2000

The fuels of water-in-oil emulsion have a potential of reducing PM(Particulate Matter) and NOx emissions, and increassing combustion efficiency in the furnaces and the burners. For making the most of the beneficial of the secondary atomization due to the microexplosion, the water droplets distributed in the oil must have the optimal sizes. The purpose of this paper is to investigate the water droplet size distribution characteristics of the different types of the static mixers. For analysing the size distribution characteristics efficiently, image analysis system was constructed and an appropriate image processing algorithm was developed. Two kinds of static mixers: Kenics type and RF type, were tested. As a results, RF type static mixer shows a better characteristics in the mean drop sizes, particularly in the condition of high water content.

• Korea-Australia Rheology Journal
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• 제18권4호
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• pp.183-189
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• 2006

High internal phase emulsions are highly concentrated emulsion systems consisting of a large volume of dispersed phase above 0.74. The rheological properties of high internal phase water-in-oil emulsions were measured conducting steady shear, oscillatory shear and creep/recovery experiments. It was found that the yield stress is inversely proportional to the drop size with the exponent of values between 1 and 2. Since the oil phase contains monomeric species, microcellular foams can easily be prepared from high internal phase emulsions. In this study, the microcellular foams combining a couple of thickeners into the conventional formulation of styrene and water system were investigated to understand the effect of viscosity ratio on cell size. Cell size variation on thickener concentration could be explained by a dimensional analysis between the capillary number and the viscosity ratio. Compression properties of foam are important end use properties in many practical applications. Crush strength and Young's modulus of microcellular foams polymerized from high internal phase emulsions were measured and compared from compression tests. Of the foams tested in this study, the foam prepared from the organoclay having reactive group as an oil phase thickener showed outstanding compression properties.

• Journal of Advanced Marine Engineering and Technology
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• 제25권4호
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• pp.904-911
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• 2001

The fuels of water-in-oil emulsion have a potential of reducing PM(Particulate Matter) and NOx emissions, and increasing combustion efficiency in the furnaces and the burners. For making the most of the beneficial of the secondary atomization due to the microexplosion, the water droplets distributed in the oil must have the optimal sizes. The purpose of this paper is to investigate the water droplet size distribution characteristics of the different types of the static mixers. For analysis the size distribution characteristics efficiently, image analysis system wes constructed and an appropriate image processing algorithm was developed. Two kinds of static mixers: Kenics type and RF type, were tested. As a results, RF type static mixer shows a better characteristics in the mean drop size, particularly in the condition of high water content.

• Elastomers and Composites
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• 제54권3호
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• pp.241-246
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• 2019

Carbon master batch (CMB) rubber sheets, which are stored in stacks, are difficult to separate during reuse because of the adhesion between sheets caused by the stacked weight over time. To solve this problem, in the actual rubber product manufacturing process, various anti-tacking agents (solid powder or liquid surfactants) are applied to the sheet surface. In this study, the emulsion samples of zinc (Zn)-stearate/triethanolamine (TEA)-stearate mixtures were prepared using TEA-stearate as a surfactant, prepared using an industrially manufactured Zn-stearate powder, and their basic anti-tacking properties were studied. During the process of manufacturing emulsion, a heat treatment process and an auxiliary surfactant were introduced to improve the dispersion stability. Results showed that the heat-treated sample exhibited a significant improvement in terms of sedimentation, storage stability, and anti-tacking characteristics since the Zn-stearate particles were reduced to a smaller size by the heat-treatment than that of the original Zn-stearate powder.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 봄 학술발표회 논문집
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• pp.291-292
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• 2003

Amphiphilic block copolymer는 self-assembly특성을 가지고 있기 때문에 선택된 용매 속에서 nanoscale-domain 즉 micelle을 형성할 수 있다. 이러한 특성은 기타 불용성 물질을 가용화하고 colloidal particle을 안정화시키거나 micro-emulsion을 형성할 수 있어 pharmaceutics, drug delivery system등 영역, 그리고 emulsion stabilizer, thickener, dispersion agent등으로 사용될 수 있다. (중략)

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.427.1-427.1
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• 2002

To improve stability and transfection efficiency, a novel combination of cationic emulsion and galactosylated chitosan was developed for targeted gene delivery. Six formulations of cationic liposome and our novel emulsion were prepared for comparison of stability and transfection efficiency. Cationic liposomes composed of 3［N-(N.N dimethylaminoethylene) carbamoyl］ cholesterol (DC-Chol) and dioleyl phophatidyl ethanolamine (DOPE) were prepared by extrusion method and cationic emulsions composed of DC-Chol. DOPE. castor oil, and Tween 80 were prepared by sonication method. (omitted)

• 대한화장품학회지
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• 제35권3호
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• pp.179-191
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• 2009

본 연구에서는 poly(oxyethylene) hydrogenated castor oils (HCOs)/오일/에탄올/물로 이루어진 에멀젼에 대한 에탄올의 영향을 연구하였다. 에멀젼은 고에너지법인 균질기(homogenizer)를 병합하여 제조하였다. 에멀젼에 대한 에탄올의 영향을 평가하기 위해 입자 크기와 입자 분포 등의 물리적 특성을 측정하였으며 다른 성분의 조성은 같도록 하였다. HCO-20의 경우 에멀젼의 크기가 마이크로미터 크기에서 에탄올이 증가할수록 입자의 크기가 감소하는 것을 확인하였다. HCO-30의 경우 계면활성제 농도 4.00 %에서 입자 크기가 나노미터 크기로 나타났으며, 에탄올의 농도가 4.25 % 일 때 조성 1에서 입자 크기가 $128.15{\pm}1.06nm$이고 조성 2에서는 $136.10{\pm}0.99nm$로 가장 안정한 나노에멀젼이 생성되었다. 마찬가지로 HCO-40은 계면활성제 농도 4.00 %에서 입자가 나노미터 크기로 나타났으며, 에탄올이 4.50%일 때 조성 1에서 입자 크기가 $115.85{\pm}0.78nm$이고 조성 2는 $121.15{\pm}0.35nm$로 안정한 나노에멀젼이 생성되었다. HCO-60의 경우에서는 계면활성제 농도 4.00 %, 에탄올 농도 2.25 %에서 에멀젼의 크기가 $262.35{\pm}0.64nm$인 안정한 나노에멀젼이 생성되었다. 마이크로 크기의 에멀젼에서는 에탄올의 함량이 증가할수록 입자의 크기가 감소하는 것을 알 수 있었고, 나노에멀젼에서는 에탄올의 특정 농도에서 최저값을 나타냄을 확인하였다. 나노에멀젼의 불안정화 과정은 Ostwald ripening에 의한 것으로 보여진다. 계면활성제 종류에 따른 에멀젼에 대한 에탄올의 영향을 연구함으로써 안정한 에멀젼을 만들기 위한 에탄올의 함량을 계산할 수 있을 것으로 사료된다.

• 공업화학
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• 제4권2호
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• pp.423-431
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• 1993

Glycerol monostearate/POE(100) monostearate 혼합비이온계면활성제를 유화제로 사용한 O/W 에멀젼에 고급알코올인 1-hexadecanol/1-octadecanol 혼합물을 보조유화제로 첨가하여, 상거동 및 유동특성을 관찰하였다. 고급알코올의 결정구조가 변화하는 전이점은 1-hexadecanol/1-octadecanol의 조성에 따라 서로 다른 값을 가지며, 2/1의 비율에서 최저값을 나타내었다. 고급알코올의 첨가에 따라 에멀젼 내에는 액정이 형성되며, 이들로 인하여 에멀젼 입자간 응집체인 2차 입자가 형성되어 에멀젼의 점성도가 증가하였다. 에멀젼계의 온도가 고급알코올의 전이점 이하로 저하되면, 고급알코올의 지방족 사슬의 운동성이 제한된 겔구조가 형성되어 점성도가 증가하였으나 시간이 경과함에 따라 액정이 사라지고 에멀젼의 점성도도 저하되었다. 용액 내의 분산되는 양(본 실험에서는 2wt%) 이상의 고급알코올을 첨가해야 에멀젼 내에서 고급 알코올/계면활성제/물이 액정을 형성하였으며, 과량(본 실험에서는 10wt%)의 고급알코올을 사용하면 2차입자가 형성되지 않았다.

• KSBB Journal
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• 제29권5호
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• pp.385-391
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• 2014

In this study, the emulsion dispersion stability of optimizing storage temperature was investigated. The system was based on oil/water (O/W) emulsions. In order to evaluate the stability, mean diameter of droplet was measured as a function of temperature with various mixed hydrophilic lipophilic balance (HLB). In addition, the correlations between phase inversion temperature (PIT) and the optimum storage temperature were probed. In this system, majority of the smallest droplet was shown at temperature of $20^{\circ}C$ below PIT. Whether the temperature was increased or decreased from the optimum, size of the droplet increased. According to the mixed HLB, the particle size and optimum storage temperature were also affected. As the concentrations of surfactant were increased, the size of particle decreased with lower optimum temperature for storage. If the surfactant (4 wt%) were mixed with HLB, the optimum storage temperature was $21^{\circ}C$ for maintaining the size of smallest droplet at 108.3 nm in diameter. At above optimum condition, increased size of particle was observed approximately 4 % increases from 108.2 nm to 112.3 nm after 600 hours. The size of particle in emulsion was maintained stably without any considerable effect of Ostwald ripening phenomena at the optimum storage temperature with low polydispersity index.

• 공업화학
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• 제9권2호
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• pp.261-267
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• 1998

본 논문에서는 Winsor systems으로부터 제조된 AOT 에멀젼의 안정성을 염화나트륨의 농도 변화에 따라 관찰하였다. 에멀젼은 헵탄+염화나트륨 수용액+AOT고 구성하였다. 염화나트륨 농도의 증가에 따라 안정성은 증가를 보이다가 일정 농도 이후에는 안정성이 급격히 감소하였다. 저 농도 염화나트륨에서는 크리밍 현상이 주로 유상과 수상의 비중 차이에 의한 단일 입자의 상승에 기인하였다. 시간 경과에 따른 크리밍 현상의 모델를 개발하여 적용한 결과 저 농도의 염화나트륨에서는 실험 결과와 잘 일치하였으나 고 농도의 염화나트륨에서는 에멀젼 입자가 작아지면서 (입자의 부력이 감소) 입자 사이의 반발력이 감소하고 오히려 인력이 증가하면서 안정성이 감소하였다.