• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.9
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• pp.895-900
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• 2012

This paper aims to examine the effect of nanodroplets on pool-type absorption heat transfer enhancement and to find the relationship between the dispersion stability and the absorption performance. The concentrations of oil and surfactant are considered as the key parameters. $C_{12}E_4$ and Tween20 are used as the surfactants and N-decane oil is added to the $NH_3/H_2O$ solution to make the binary nanoemulsion fluids. Binary nanoemulsion fluids are dispersed by the ultrasonic vibrator and the stirrer under specific conditions. The dispersion stability of binary nanoemulsion fluids for each oil concentrations is evaluated from the droplet size and Tyndall effect analysis. The absorption performance of binary nanoemulsion fluids is compared with the result of dispersion stability. In addition, it is found that the binary nanoemulsion fluid is a strong candidate as a new working fluid for absorption applications.

• The monthly packaging world
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• s.53
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• pp.158-161
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• 1997

• Journal of the Korean Ceramic Society
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• v.41 no.3
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• pp.242-246
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• 2004

Nano-sized a-alumina with a narrow distribution was prepared by using Flame Spray Pyrolysis (FSP). The microemulsion of water in oil (W/O) was prepared to make ultrafine droplets for FSP process. Kerosene (fuel) as a continuos phase and Al(NO$_3$)$_3$$.$9$H_2O$ (oxidizer) aqueous solution as a dispersed phase were prepared for microemulsification. The microemulsion with dispersion stability was obtained by adjusting the composition of 80 vol% kerosene, 10 vol% aqueous solution, and 10 vol% emulsifying agent. Microemulsion was sprayed onto the flame by using two-fluid nozzle spray gun under the condition of 0.03 ㎫ air pressure. The synthesized products were $\alpha$-alumina phase with the size of 20 to 30 nm.

• The monthly packaging world
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• s.325
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• pp.48-52
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• 2020

• Proceedings of the KSEE Conference
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• 2006.03a
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• pp.39-50
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• 2006

• Applied Chemistry for Engineering
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• v.22 no.3
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• pp.328-331
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• 2011

ZnSe quantum dots (QDs) were prepared by employing water-containing Dioctyl sodium sulfosuccinate (AOT) reversed micelles (microemulsions) and the silica-encapsulated ZnSe QDs were obtained by a direct injection of tetraethyl orthosilicate (TEOS) into the microemulsion system. When the QDs were coated by silica, well-defined spherical shapes were formed and the average size of the QDs was near 7 nm. In addition, the photoluminescence (PL) efficiency of the QDs was reduced from 8.0 to 1.1% as they were encapsulated by silica. However, the solid layers of the silica-encapsulated ZnSe QDs on gold surfaces showed the excellent photostability. In particular, they are cadmium free and thus, less toxic. Moreover, the present method does not require a hot reaction temperature or extremely toxic H2Se gas as a Se precursor. Accordingly, the method can be a safer and more economical process for producing silica-encapsulated ZnSe QDs, which may be a potential media for biosensors.

• Rubber Technology
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• v.22 no.2
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• pp.105-118
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• 2021

• Transactions of the Korean Society of Mechanical Engineers B
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• v.39 no.8
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• pp.677-682
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• 2015

We simulate an emulsion system under simple shear rates to analyze its rheological characteristics using the lattice Boltzmann method (LBM). We calculate the relative viscosity of an emulsion under a simple shear flow along with changes in temperature, shear rate, and surfactant concentration. The relative viscosity of emulsions decreased with an increase in temperature. We observed the shear-thinning phenomena, which is responsible for the inverse proportion between the shear rate and viscosity. An increase in the interfacial tension caused a decrease in the relative viscosity of the decane-in-water emulsion because the increased deformation caused by the decreased interfacial tension significantly influenced the wall shear stress.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.26 no.1
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• pp.139-148
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• 2000

The osmotic pressure is a one of the most important factor affecting stabilization of multiple emulsion in a law hours after experiment. To understand and decrease osmotic pressure between Wl phase and W2 phase, a kinds of humectants were introduced in outer water phase. As a result, Betaine and Glucose had an excellent effect reducing osmotic pressure and NaCl made W/O/W emulsion more stable than MgSO4 did when introduced in inner water phase.

• Korean Journal of Food Science and Technology
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• v.13 no.4
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• pp.273-282
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• 1981

The antioxidant actilvity of ethanol-extracts (M-2 and M-30), which had been obtained from a Maillard-type browning mixture after 2 and 90 hr browning, and BHA, BHT, TBHQ, and ascorbyl palmitate It·as investigated in soybean oil and soybean oil-water emulsion systems. The activity of the extracts and antioxidants was estimated by comparing the POV and TBA value development of the corresponding substrates with that of controls. The substrates and controls were stored at $45.0{\pm}0.5^{\circ}C$ for 25 days. The activity of the extracts (10 ml each) and antioxidants (0.02%) based mainly on the POY development of the corresponding anhydrous substrates was, in decreasing order, as follows ; As. palmitate, TBHQ > M-30, M-2 > BHT, BHA The actilvity of the extracts and antioxidants in tile oil-water emulsion substrates was, in decreasing order, as follows : As. palmitate > M-30, M-2 > BHT, TBHQ, BHA The activity of the extracts appeared to be more effective in the oil-water emulsion system than in the anhydrous system, and it f·as greater than that of the phenolic antioxidants such as BHA, BHT, and TBHQ in the oil-water emulsion system.