• Journal of ILASS-Korea
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• v.19 no.4
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• pp.188-196
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• 2014

The spray and combustion characteristics of n-dodecane fuel were investigated in a CVCC (constant volume combustion chamber). The selection of ambient conditions for the spray followed ECN (engine combustion network) guidelines, which simulates the ambient condition of diesel engines at start of fuel injection. ECN is a collaboration network whose main objective is to establish an internet library of well-documented experiments that are appropriate for model validation and the advancement of scientific understanding of combustion at conditions specific to engines. Therefore repeatability of the experiments with high accuracy was important. The ambient temperature was varied from 750 to 930 K while the density was fixed at around $23kg/m^3$. The injection pressure of the fuel was varied from 500 to 1500 bar. The spray was injected in both non-reacting ($O_2$ concentration of 0%) and reacting conditions ($O_2$ concentration of 15%) to examine the spray and the combustion characteristics. Direct imaging with Mie Scattering was used to obtain the liquid penetration length. Shadowgraph was implemented to observe vapor length and lift-off length at non-reacting and reacting conditions, respectively. Pressure data was analyzed to determine the ignition delay with respect to the spray and ambient conditions.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.3 s.47
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• pp.419-426
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• 2004

The nano-ceramide capsulation is a technique that capsulates ceramide III and tocopheryl linoleate at the mono-vesicle to act on the horny layer in skin. In this technique, $0.5{\~}5.0\;wt\%$ of hydrogenated lecithin and $0.01{\~}2.00\;wt\%$ of lysolecithin are used as the membrane-strengthen agents of the mono-vesicle and $5.0{\~}10.0\;wt\%$ of propylene glycol and $5.0{\~}10.0\;wt\%$ of ethyl alcohol are used as solvents. Active ingredients such ceramide III and tocopheryl linoleate are utilized to enhance the moisturizing efficacy and treat atopy skin. These materials do not contain synthetic emulsifiers. The optimal conditions or nano-ceramide capsulation are such that particles pass Microfludizdizer 3 times at 1,000 bar and $60{\~}70^{\circ}C$ and pH of nano capsules is $5.8{\pm}0.5.$ The average size of particles is $63.1{\pm}7.34\;nm$ showing lucid state like water by the laser light scattering. A zeta potential value is $-55.1\pm0.84\;mV.$ Through clinical tests, the moisturizing effect (in-vivo, n=8, p-value<0.05) showed $21.15\%$ of improvement comparison to comparison-samples and $36.31\%$ of improvement compared to the state before treatment. Moreover, the effectiveness of atopy skin showed positive reaction from 10 volunteers.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.178-191
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• 2003

OMC is essentialiy necessary compound in sun goods as organic UV protecting products. But the skin-trouble problem is raising because of skin penetration of OMC. In this study, non-capsulated pure OMC was compared with Organic-Inorganic-Nano-hybrid OMC for skin penetration force and SPF degree. Organic- Inorganic Nano-Hybrid OMC is OMC trapped in the pore of the mesoporous silica synthesized by the sol-gel method after OMC is nanoemulsified in the system of the hydrogenated Lecithin/ Ethanol/caprylic/capric triglyceride/OMC/water. OMC- nano- emulsion was obtained by a microfluidizing process at 1000bar and then micelle size in the nanoemulsion solution is 100-200nm range. Mesoporous silica nano-hybrid OMC was prepared by the process; surfactant was added in dissolved OMC-Nanoemulsion, then the rod Micelle was formed. OMC-nanoemulsion was capsulated in this rod Micelle and then silica precursor was added in the OMC-nanoemulsion solution. Through the hydrolysis reaction of the silica precursor, mesoporous silica concluding OMC-Nanocapsulation was obtained. The nano-hybrid surface of this OMC-Nanoemulsion-Inorganic system was treated with polyalkyl-silane compound. OMC-Mesoporous silica Nano-hybrids coated with polyalkyl-silane compound show the higher sun protecting factor (SPF Analyzer: INDEX 10-15) than pure OMC and could reduce a skin penetration of OMC. The physico-chemical properties of these nano-hybrids measured on the SPF index, partical size, strcture, specific surface area, pore size, morphology, UV absorption, rate of the OMC dissolution using SPF Analyzer, Laser light scattering system, XRD, BET, SEM, chroma Meter, HPLC, Image analyzer, microfluidizer, UV/VIS. spectrometer.

• Proceedings of the SCSK Conference
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• 2003.09b
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• pp.268-279
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• 2003

The nano capsulation of the ceramide was a technique that capsulated ceramide III and tocopheryl linoleate at the mono-vesicle, so as to act the horny layer in skin. It was used 0.5-5.0 wt% of hydrogenated lecithin and 0.01~2.00 wt% of lysolecithin as the membrane-strengthen agents of the mono-vesicle, 5.0~10 wt% of propylene glycol and 5.0~10.0 wt% of ethyl alcohol made by high-pressure Microfluidizer. To enhance the moisturizing efficacy and treat an atopy skin, used ceramide III and tocopheryl linoleate as the active ingredients, and it was made the nano-capsule that synthetic emulsifiers were free. The optimal condition of capsulation of nano ceramide was as follows. The conditions were 3 times at 1,000bar and 60-7$0^{\circ}C$. The particle size showed 63.1$\pm$7.34 nm such as the transparence water as the results for measuring by the laser light scattering. A zeta potential value was -55.1$\pm$0.84 ㎷. The result of the clinical test, the moisturizing effect (in-vivo, n=8, p-value<0.05) was improved 21.15% compared to control, as well as it was improved 36.31 % before the treatment. Moreover, the effectiveness of atopy skin indicated positive reaction that patients were 10 volunteers.