• Journal of the Korean Society for Precision Engineering
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• v.31 no.1
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• pp.91-96
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• 2014

We present a droplet-manipulation method using opto-thermal flows in oils. The flows are originated from Marangoni and buoyancy effects due to temperature gradient, generated by the adsorption of light on an amorphous silicon thin film. Using this method, we can transport, merge and mix droplets in an extremely simple system. Since the temperature rise during the operation is small, this method can be used for biological applications without the damage on cell viability.

• Journal of the Korean Applied Science and Technology
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• v.30 no.1
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• pp.152-159
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• 2013

Experiments of emulsion particles state of using polyglycerol ester emulsifier and the stability in accordance with the change of time were conducted using several oil. Experimental results confirmed that there is little difference in the stability and particle size depending on the type of oil. Most stable oil with polyglycerol ester is polar oil of silicon series and fatty acid ester oil, hydrocarbon oil of the nonpolar oil (Mineral oil, squalane, polydecene) was the most unstable state. And vegetable oils showed the stable form of particles with polyglycerol ester emulsifier.

• Tuberculosis and Respiratory Diseases
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• v.69 no.4
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• pp.288-292
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• 2010

Exogenous lipoid pneumonia occurs rarely in healthy people. In most cases, exogenous lipoid pneumonia is usually caused by aspiration of mineral, vegetable, or animal oil. We report the case of 42-year-old woman, who have experienced lipoid pneumonia after silicon injection into her breast for cosmetic purposes. The patient experienced fever, dyspnea, sputum, and hemoptysis after silicon injection into her breast. Chest computed tomography demonstrated non- segmental distribution of bilateral consolidation in both lung fields. A transbronchial lung biopsy specimen shows foamy microphages in alveolar spaces. Papanicolaous staining of bronchoalveolar lavage fluid showed abundant foamy marcrophages and many neutrophils. With these results, we confirmed lipoid pneumonia was associated with silicon oil injection into breast.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.10
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• pp.1688-1693
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• 2016

In this study shall investigate the influence upon the electrical property of transformer oil due to the heat among accelerated heat degradation experiment for a constant hour in the typical insulation oils of mineral base oil, silicon base oil and vegetable oil. In addition, the electric insulation performance of insulation materials in transformer shall be evaluated through the electric property analysis according to the heat degradation of epoxy insulation material, which has been used for electric facilities such as a molded transformer.

• Journal of the Korean Society for Precision Engineering
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• v.30 no.8
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• pp.864-869
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• 2013

As the size of mechanical components decreases, capillary forces and surface tension become increasingly significant. A major problem in maintaining high reliability of these small components is that of large frictional forces due to capillary action and surface tension. Unlike the situation with macro-scale systems, liquid lubrication cannot be used to reduce friction of micro-scale components because of the excessive capillary and drag forces. In this work, the feasibility of using evaporation to coat a thin film of organic lubricant on a solid surface was investigated with the aim of reducing friction. Petroleum and silicone oils were used as lubricants to coat a silicon substrate. It was found that friction could be significantly reduced and, furthermore, that the effectiveness of this method was strongly dependent on the coating conditions.

• Korean Journal of Food Science and Technology
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• v.47 no.2
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• pp.145-148
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• 2015

According to the Korea Food Additives Code, sodium metasilicate is permitted for use as a filtering agent for edible oils and fats. Sodium metasilicate is currently used as a food additives to increase the weight of shark fins. In this study, we developed an analytical method to quantify sodium metasilicate in food. Sodium metasilicate content was estimated by measuring the moisture content, pH and silicon content of shark fins. Silicon content was analyzed using inductively coupled plasma-optical emission spectrometry (ICP-OES) following microwave-assisted digestion with $HNO_3$ (65%) and $H_2O_2$ (30%). Shark fin total silicon content was $7.17{\pm}8.92mg/kg$, while the soluble silicon content was $2.34{\pm}3.80mg/kg$. After soaking raw shark fin in an aqueous solution of sodium metasilicate, fin weight, pH and silicon content were measured. These results would be used as the basic information for shark fins safety management.

• Journal of Life Science
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• v.31 no.5
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• pp.502-510
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• 2021

The objective of this study was to develop a novel ticagrelor-loaded self-nanoemulsifying drug delivery system with an enhanced solubility and dissolution rate. Numerous oils and surfactants were screened, then medium chain triglyceride (MCT) oil and the surfactants polyoxyethylene sorbitan monooleate (Tween 80) and Labrafil M1944CS were selected for the preparation of the ticagrelor-loaded self-nanoemulsifying drug delivery system. A pseudo-ternary phase diagram was constructed to detect the nanoemulsion region. Of the various formulations tested, the liquid SNEDDS, composed of MCT (oil), Tween 80 (surfactant), and Labrafil M1944CS (cosurfactant) at a weight ratio of 20/70/10 produced the smallest emulsion droplet size (around 20.56±0.70 nm). Then, particle size, polydispersity, and zeta potential were measured using drugs containing liquid SNEDDS. The selected ticagrelor-loaded liquid SNEDDS was spray-dried to convert it into a ticagrelor-loaded solid SNEDDS with a suitable inert carrier, such as silicon dioxide, calcium silicate, or magnesium aluminometasilicate. The solid SNEDDS was characterized by scanning electron microscopy, transmission electron microscopy, and in vitro dissolution studies. SEM, PXRD, and DSC results suggested that amorphous ticagrelor was present in the solid SNEDDS. Also, the solid SNEDDS significantly increased the dissolution rate of ticagrelor. In particular, the emulsion particle size and the polydispersity index of the solid SNEDDS using silicon dioxide (SS1) as a carrier was the smallest among the evaluated solid SNEDDS, and the flowability and compressibility result of the SS1 was the most suitable for the manufacturing of solid dosage forms. Therefore, solid SNEDDS using silicon dioxide (SS1) could be a potential nano-sized drug delivery system for the poorly water-soluble drug ticagrelor.

• Composites Research
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• v.12 no.2
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• pp.70-81
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• 1999

Resin transfer molding(RTM) as a composite manufacturing process is currently of great interest in the aerospace industry requiring high performance composite parts. In this study, an analysis of mold filling in the RTM process was carried out by numerical simulation using finite element/control volume technique. Experimental work for the visualization of resin flow through fibrous preform was also conducted in order to quantitatively measure the permeabilities of the fiber mats and to evaluate the validity of the developed numerical code. The different types of fiber mats and silicon oils were selected as reinforcements and resin materials, respectively. The effects of fibrous preform structure, mold geometry, and preplaced insert on the flow front patterns during mold filling were examined by integrating the model predictions and experimental results. The flow fronts predicted by numerical simulation were in good agreement with those observed experimentally. However, according to the regions of the mold, some deviations between predicted and observed flow fronts could be found because of non-uniform fiber volume fraction. Weldline locations for the resin flow through round insert preplaced in the mold could be qualitatively deduced based on predicted flow fronts.

• The Korean Journal of Rheology
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• v.10 no.4
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• pp.185-194
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• 1998

Flow-induced voids during resin impregnation and poor fiber wetting give serious effects on the mechanical properties of composites in resin transfer molding process. In order to better understand the characteristics of resin flow and to investigate the mechanism of void formation, flow visualization experiment for the resin impregnation was carried out on plain weaving glass fiber mats using silicon oils with various viscosity values. The permeability and the capillary pressure for the fiber mats of different porosities were obtained by measuring the penetration length of the resin with time and with various injection pressure. At low porosity and low operating pressure, the capillary pressure played a significant role in impregnation process. Video-assisted microscopy was used in taking the magnified photograph of the flow front of the resin to investigate the effect of the capillary pressure on the void formation. The results showed that the voids were formed easily when the capillary pressure was relatively high. No voids were detected above the critical capillary number of 2.75$\times$$10^{-3}, and below the critical number the void content increased exponentially with decrease of the capillary number. The content of void formed was independent of the viscosity of the resin. For a given capillary number, the void content reduced with the lower porosity of the fiber mat.