• Tribology and Lubricants
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• v.7 no.1
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• pp.55-60
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• 1991

The emulsion lubrication is expected to get the effects of cooling and lubrication in metal cutting. The purpose of this research was to investigate the lubrication characteristics of the emulsion in a region of the elastohydrodynamic lubrication by experiments using o/w type emulsion lubrication. With the line contact frictional experiment apparatus which is the model of a rolling mechanism, friction coefficient, and oil film thickness were measured. By analyzing these experimental data with the variables of emulsion concentration, load, and rolling velocity, the following results are obtained. Emulsion viscosity $\eta$ for the concentration and pressure can be calculated by the following equation $\eta=\eta_o e^{\alphap}\cdot e^{\beta \phi}$. Where $\beta = (-3.7242+\phi)/\phi, 5%\leq \phi \leq 15%$.

• Journal of Pharmaceutical Investigation
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• v.37 no.2
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• pp.85-94
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• 2007

The objective of this study is to prepare a stable delivery systems containing polyethoxylated retinamide(PERA) - derivatives of retinoic acid, effective anti-wrinkle and anti-acne agent. Cubic liquid crystalline phase gel (CLCPG) and cubosomes containing various concentrations of PERA were prepared to investigate the physicochemical properties. Furthermore, stability and transdermal absorption efficacy of the CLCPG containing PERA were investigated in comparison with oil-in-water (O/W) emulsions which are predominantly used as a topical formulation. CLCPG increase the stability of PERA in comparison with O/W emulsion. For tropical application, CLCPG containing PERA shows higher moisturizing effect than that of O/W emulsion. In skin permeation test, CLCPG shows higher PERA deposit on epidermis. With its specific physicochemical property caused by the glyceryl oleate, CLCPG itself could be used for stabilizer of various actives and applied as an effective delivery system for topical application. Cubosome, nano-sized dispersed CLCPG, is also expected to be applied in a various field of industry like food, cosmetics and pharmaceuticals.

• Proceedings of the Korean Printing Society Conference
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• 2002.05a
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• pp.32-32
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• 2002

디지탈 윤전 등사기 또는 디지털복사 인쇄기(digital duplicator)라고 불리우는 사무용 소형 단색 윤전 인쇄기는 컴퓨터 스캐닝 기술과 스텐실 열천공 기술의 발달로 손쉽게 인쇄기상에서 자동복사 제판이 가능해 짐에 따라 우리나라에 1990년대부터 학교, 관공서, 군 및 교회등의 시험지와 홍보전단지 인쇄용으로 널리 보급되었다. 여기에 사용되는 잉크는 카트리지에 장착식으로 공급되는데, 에멀젼 잉크로서 천공으로 이루어진 스텐실 화상 뒷면으로부터 가압 통과되어 인쇄용지에 윤전식으로 인쇄된다. W/O형 에멀젼 잉크가 그 기본 전형이 된 것은 스텐실의 미세구멍을 통과하도록 큰 로라압력을 받아야 하는 잉크는 우선적으로 높은 점도이어야 하나 수십 마이크론의 미세구멍을 쉽게 빠져 나가도록 침투성이 빨라야 하는 이중적 레올로지 특성이 요구되기 때문이다. 그러나 에멀젼의 원천적인 불안정성과 물과 기름의 상호 대립적인 물리 \ulcorner화학적 특성을 주목하고 번짐, 얼룩, 배면침투, 광택문제, 건조성 지연 등의 인쇄품질을 향상시키고져 그동안 많은 연구개발이 노력이 있어 왔다. 이에 대하여 세계 시장을 크게 장악하고 있는 일본의 특허를 주로 검토하여 디지털 인쇄기용 W/O 에멀젼 잉크 기술 및 현황에 대해서 연구 조사하였다.

• Journal of the Korean Applied Science and Technology
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• v.16 no.1
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• pp.95-103
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• 1999

In the separation of toluene/n-heptane mixture by the emulsion type liquid membrane in a batch system, the effect of surfactants on the separation factor and membrane stability were studied over the surfactant concentration ranging from 0.1 to 1.5 wt% at the contact time of 5 and 10 minutes and the settling time 5 and 10 minutes. The surfactants used were triethanol amine lauryl sulfate. The separation factor reached its maximum value at the surfactant concentration of 0.5 wt%. It was found that the percentage of membrane breakup reached its minium values and the separation factor showed its maximum value at the surfactant concentration of 0.5 wt%, which confirmed that efficient separation could be effect when emulsion liquid membrane were stable because of low membrane break up.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.25 no.4 s.34
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• pp.75-95
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• 1999

A colloid refers to dispersed particles of a solid or liquid having the diameter of about $10^{-5}-10^{-7}cm$. Such colloidal silver is produced by electrolysis. In this paper, colloidal silvers of various concentrations according to charge amount and time are produced, and their anti-microbial activities are measured. And optimum conditions for emulsion are measured by varying the concentration of colloidal silvers. Further, stability of the emulsion is measured with a Zeta potential, chrome meter by applying colloidal silvers to creams (W/Si, O/W, MLV).

• Proceedings of the SCSK Conference
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• 1999.10a
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• pp.75-95
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• 1999

A colloid refers to dispersed particles of a solid or liquid having the diameter of about $10^{-5}$ - $10^{-7}$. Such colloidal silver is produced by electrolysis. In this paper. colloidal silvers of various concentrations according to charge amount and time are produced, and their anti-microbial activities are measured. And optimum conditions for emulsion are measured by varying the concentration of colloidal silvers. Further, stability of the emulsion is measured with a Zeta potential. chrome meter by applying colloidal silvers to creams (W/Si. O/W, MLV).

• Tribology and Lubricants
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• v.5 no.1
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• pp.51-56
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• 1989

The Lubricational characteristics of O/W Emulsions of beef tallow and mineral oil based lubricants are studied in a roller on disk apparatus. It is revealed that the coefficients of friction with both emulsion lubricants exhibit essentially similar behavior; that is, they rapidly decrease to 0.1% concentration and after they constants with increasing oil concentration, and that, with oil in water emulsions of a concentrations as low as 5wt% practically forms a elastohydrodynamic film. One hand, surface temperature effect on lubricants has virtually no severe, and that, the minimum EHL film chickness estimated that it begins to increase at a concentration of several percent; the effect of particle diameter becomes maked there after.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.6
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• pp.1021-1026
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• 2000

The removal of cadmium, copper and chromium ions was carried in a phase transfer reactor using W/O(water in oil) microemulsion containing sodium di[2-ethylhexyl] sulfosuccinate(AOT) and isooctane system. Removal efficiencies and mass transfer rate of $Cd^{2+}$, $Cu^{2+}$ and $Cr^{3+}$ were increasing with increasing pH of aqueous solution. However, $Cr^{6+}$ was not extracted by W/O microemulsion with AOT/isooctane system. It was found that removal of heavy metal ions were required an attractive electrostatic interaction between the metal ions and W/O microemulsion. The relationship between mass transfer rate. Jo of $Cd^{2+}$, $Cu^{2+}$ and $Cr^{3+}$ and pH of aqueous solution by W/O microemulsion suggested.

• Proceedings of KOSOMES biannual meeting
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• 2006.05a
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• pp.103-108
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• 2006

Treatment of O/W Emulsion is very important to develop 15ppm Bilge Separator for new IMO regulation It is too difficult to demulsify the emulsion in the bilge waste water, so we use chemical treatment to break emulsion stability. Broken oil particle is treated by flotation 15ppm Bilge Separator on the Ship doesn't have enough time to treat Bilge waste water because of limited space in the ship. For the solution to this problem, we experiment to find primary factors as coagulant, pH, amount of inputting coagulant, and type of flotation. On the basis of test results, we decided primary factors.

• Journal of the Korean Applied Science and Technology
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• v.36 no.1
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• pp.226-236
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• 2019

In this study, functional and emulsifying properties of oil extracted by supercritical carbon dioxide from balloonflower(Platycodon grandiflorum A. DC) seeds were investigated. The oil was lower in total polyphenol content(8 mg/100 g), but higher in ${\alpha}$-tocopherol(14.15 mg/100 g), ${\beta}$-sitosterol(116 mg/100 g) and stigmasterol(8 mg/100 g) contents than seeds. Based on DPPH radical scavenging activity, the oil($IC_{50}=1235.5{\mu}g/mL$) showed similar antioxidant activity to the seeds($IC_{50}=1138.2{\mu}g/mL$). At 1%(w/w) lecithin, O/W emulsion with balloonflower seeds oil had turbidity, microscopic image, mean particle size and emulsion stability similar to emulsion with soybean oil, but had lower turbidity and emulsion stability and larger mean particle size than emulsion with perilla seeds oil. Its surface tension was similar to perilla oil emulsion.