• 한국광학회지
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• 제2권1호
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• pp.1-6
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• 1991

회절현상을 이용하여 복수 미세 입자의 특성 측정을 위한 격자형의 검지기를 사용한 데이터 처리방식을 제안하고 이에 따른 광학 및 신호처리 시스템을 구성하였다. 에너지 분포함수의 최대치와 최소치를 이용하여 같은 분무기로 분무된 증류수, 알코올, 실리콘 오일, 글리세린 등의 분포를 측정했는데 최대치와 최소치에 의해 구한 입자의 크기가 서로 잘 일치하였다.

• Korean Membrane Journal
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• 제1권1호
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• pp.43-49
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• 1999

Separation of soluble oil was investigated during filtration of cutting oil emulsion using various commercial ultrafiltration membranes. The surface properties of membranes used were hydrophilic hydrophobic and modified surfaces by various surfactant pretreatments. Conditions varied include stirring speed transmeembrane pressure membrane type and surfactant type for pretreatment. The results give some indication of mechanisms occurring at the membrane surface. Surfactant pretreatments significantly improved water flux and UF flux of hydrophilic regenerated cellulose(up to 2.4x for YM100) and hydrophobic polysulfone (up to 2.2x for PTHK) membranes depending on surfactant type and operating conditions. The UF flux enhancement was attributed to membrane swelling and reduction of interfacial surface tension between oil droplets and membrane surface. unexpectedly the hydrophilic membranes revealed greater flux enhancement than the hydrophobic membranes. The results also showed a greater improvement in UF flux at lower operating pressure.

• 설비공학논문집
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• 제7권4호
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• pp.694-702
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• 1995

When a small absorbing particle is exposed to a strong thermal radiation incidence, it moves towards or away from the radiation source due to the nonuniform internal absorption of the radiation. It is called the photophoretic phenomena and governed by the asymmetry factor. An asymmetry factor for the total wavelength range is calculated to estimate the photophoretic phenomena of a particle in a combustor or in the atmosphere and compared to that for a single wavelength. The samples are soot particulates, water droplets, ice particles, silicon particles, $SiO_2$ particles, aluminium oxide particles, whose spectral complex refractive index are available. Although differences between total and monochromatic asymmertry factors are not much for relatively uniform distribution of the spectral refractive index, they are great in general. Therefore the use of the monochromatic factor will considerably deteriorate the accuracy of the calculation of the photophoresis.

• 설비공학논문집
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• 제11권6호
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• pp.725-732
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• 1999

It is usual to use hydrophilic-coated aluminum foil for evaporator fin of air-conditioners to reduce air flow resistance caused by the water droplets condensed on the fin surface. The major effect of a hydrophilic coating is to reduce the contact angle of the condensate and prevent bridging of the condensate between the adjacent fins. The performance of hydrophilic coating generally tends to be degraded as it is used since the coating material is washed down by the condensate. In the present work, several types of hydrophilic coatings were evaluated in terms of durability of hydrophilicity, corrosion resistance and heat resistance. Results showed that an improved hydrophilic coating of resin type presented superb qualify in terms of durability and corrosion resistance while having almost the same level of qualify in heat resistance compared with the others.

• 한국막학회:학술대회논문집
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• 한국막학회 2004년도 Proceedings of the second conference of aseanian membrane society
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• pp.74-77
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• 2004

Porous membranes were prepared via thermally induced phase separation (TIPS) of (ethylene-co-vinyl alcohol) (EVOH)/glycerol mixtures. The liquid-liquid (L-L) phase boundaries are shifted to higher temperature when the ethylene contents in EVOH increase. Moreover, the kinetic study proved that the growth of droplets formed by the general liquid-liquid (L-L) phase separation obeyed a power-law scaling relationship in the later stage of spinodal decomposition (SD). A new phase separation mechanism was presented, in which the L-L phase separation could be resulted from the crystallization. The hollow fiber membranes were prepared. The membranes showed asymmetric structures with skin layer near the outer surface, the larger pores just below the skin layer and the smaller pores near the inner surface. The effect of ethylene content (EC) in EVOH, cooling water bath temperature and take-up speed on membrane performance was investigated.

• 동력기계공학회지
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• 제2권1호
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• pp.25-30
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• 1998

In order to investigate the droplet size distribution and Sauter Mean Diameter in a ultra high pressure diesel spray, fuel was injected with ultra high pressure into the environments of high pressure and room temperature by an Electronic Hydraulic Fuel Injection System. Droplet size was measured with the immersion liquid sampling technique. The immersion liquid was used a mixture of water-methycellulose solution and ethanol. The Sauter Mean Diameter decreased with increasing injection pressure, with a decrease environmental pressure (back pressure) and nozzle diameter. Increasing the injection pressure makes the fuel density distribution of the spray more homogeneous. An empirical correlation was developed among injection pressure, air density, nozzle diameter and the Sauter Mean Diameter of spray droplets.

• Journal of Industrial and Engineering Chemistry
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• 제67권
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• pp.123-131
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• 2018

Using mixed nonionic surfactants Span/Tween, we investigated the effects of HLB value on the O/W emulsion stability and rheological behaviors. In this study, MS-01 (Span 60 & Tween 60) and MS-02 (Span 80 & Tween 80) was used as mixed nonionic surfactants. We considered required HLB value 10.85 and selected corresponding HLB value range 8-13. The droplet size distributions, droplet morphology, rheological properties, zeta-potential and creaming index of the emulsion samples were obtained to understand the mechanism and interaction of droplets in O/W emulsion. The results indicated that optimal HLB number for O/W emulsions was 10.8 and 10.7, while using MS-01 surfactant and MS-02 surfactant respectively. MS-01 (HLB = 10.8) sample and MS-02 (HLB = 10.7) sample showed smallest droplet size and highest zeta-potential value. Rheological properties are measured to understand rheological behaviors of emulsion samples. All emulsion samples showed no phase separation until 30 days storage time at $25^{\circ}C$.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.3524-3528
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• 2007

In this study, the Peltier effect was applied to eliminate moistures in the air enclosed by a cabinet. We have developed the new electronic dehumidifier which has a new function of automatically evaporating the condensed water inner cabinet into the outside air. To obtain this function, the processes of dehumidification is that it condensed the moistures on the cold side heat sink and drained it into the hot side heat sink by the both gravitational and capillary forces and the droplets on the hot side heat sink surface was evaporated into the air outside the cabinet by the heat conducted through the hot side heat sink surface and the forced heat convection through the fan for cooling hot side heat sink. Compared to existing electronic dehumidifiers, this manufactured one showed a good performance that the electric power consumption for the same dehumidifying quantity was reduced by 50% compared with that of existing ones.

• 대한수의학회지
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• 제18권2호
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• pp.87-95
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• 1978

Election microscopic investigation were conducted on the mature mouse (B.W. about 25g) liver which was treated with Ginseng water extract during three, six and nine days respectivelly after carbon tetracholride injection into abdominal cavity. The results obtained were as follows: The liver cells of control group treated with carbon tetrachloride alone were restored slowly. The liver cells of experimental group treated with Ginseng water extract after carbon tetrachloride injection, however, were shown the appearance of well-developed ${\gamma}-ER$ and Golgi complex, marked aggregation of glycogen particles, and a number of large lipid droplets which are attached markedly with glycogen particles as compared to the control group. As these findings, it could be suggested that Ginseng gives an activation to restore the damaged liver cells.

• 한국전산유체공학회지
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• 제12권1호
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• pp.28-34
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• 2007

This study evaluates the performance of the packed bed scrubber and proposes the optimization of spray system for improvements of collection efficiency. The packed bed scrubber is used primarily in the semiconductor manufacturing process. The mean diameter of entering solid particles in scrubber is the submicron. The impaction between water droplets and solid particles is an important factor in removing the solid particles. Thus, the coverage area of spray system influences on the collection efficiency. The collection efficiency of a single droplet is calculated through the mathematical model and numerical calculations are performed for coverage area for each nozzle type (Droplet diameters: 500, 319.5, $289.5{\mu}m$) and injected directions (0, 15, $30^{\circ}$). In case of nozzle type 3, the collection efficiency of a single droplet is highest but the collection efficiency of spray system has lowest value because the ratio of flow rate between the gas and water is below 0.1. The results show the coverage area ratio is about 85% in the case of nozzle type 3 and downward sirection $15^{\circ}$. It was shown that a coverage area increase by two times than an existing spray system. In simulation of demister, collection efficiency by demister is predicted about 80% and the pressure drop in demister is below 3.5 Pa.