• 한국전기화학회:학술대회논문집
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• 2002.04a
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• pp.10-10
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• 2002

• Journal of computational fluids engineering
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• v.21 no.3
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• pp.31-38
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• 2016

The FDS-HCIB method is expanded to simulate water-oil-air flows around oil booms under relative motion, which is intended to increase the thickness of contained oil. The FDS scheme captures discontinuity in the density field and abrupt change of the tangential velocity across an interface without smearing. The HCIB method handles relative motions of thin oil booms with ease. To validate the developed FDS-HCIB code for water-oil-air flow around a moving body, the computed results are compared with the reported experimental results on the shape, length, and thickness of the oil slicks under towing. It is observed that the increase in pressure field between two barriers lifts the oil slick and the interfacial wave propagates and reflects as one barrier gets closer to the other barrier.

• Journal of Korean Society on Water Environment
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• v.25 no.4
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• pp.547-552
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• 2009

Because of refractory property of light, the travel path of UV light becomes longer than the straight line and shorter solely in water as UV light passes sequentially through air, quartz and water. Note that water significantly absorbs UV light. Hence, UV intensity shall be estimated to be lower when refraction is neglected than it is considered. Reflection is also critical for the design of UV radiation system. While the reflection at the interface of air and quartz is low enough to ignore, it is too high to be ignored at the interface of quartz and water. Assuming constant power, smaller length to width ratio of UV reactor is beneficial and single-lamp system is preferred to multi-lamps. Under the given cross section, optimal lamp positions could be decided. For example of an elliptical reactor with dual lamps, the optimal lamp locations shall be the 1/3 and 2/3 position of the longer axis.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1364-1366
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• 1994

In this paper, the monolayers of the polymers which polyion-complexed with PAA at the air-water interrace can be transferred on to solid substrates such as porous fluorocarbon membranes filter and quartz crystal microbalance. The properties of the monolayers and the LB films investigated by ${\pi}-A$ isotherms, FT-IR, DSC, deposition ratio, QCM, and SEM will be discussed. In addition, it was attempted to investigated the surface characterics of polymer/metal compound LB films in the air/water interface.

• 한국전산유체공학회:학술대회논문집
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• 2011.05a
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• pp.54-57
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• 2011

In this paper we present an algorithm about how to simulate two dimensional dam breaking with lattice Boltzmann method (LBM). LBM considers a typical volume element of fluid to be composed of a collection of particles that represented by a particle velocity distribution function for each fluid component at each grid point. We use the modified Lattice Boltzmann Method for incompressible fluid. This paper will represent detailed information on single phase flow which considers only the water instead of both air and water. Interface treatment and conservation of mass are the most important things in simulating free surface where the Interface is treated by mass exchange with the water region. We consider the surface tension on the interface and also bounce back boundary condition for the treatment of solid obstacles. We will compare the results of the simulation with some methods and experimental results.

• Bulletin of the Korean Chemical Society
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• v.29 no.8
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• pp.1485-1490
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• 2008

Dumbbell-shaped aromatic amphiphilic molecules consisting of a dodeca-p-phenylene as a rigid segment and oligoether dendrons as a flexible chains were synthesized, characterized, and their aggregation behavior was investigated in the bulk and at the air-water interface. In contrast to the molecule 2 which shows a nematic liquid crystalline state, molecule 1 based on shorter dendritic chains was observed to self-assemble into a 3-D primitive orthorhombic supercrystal. And molecule 1 at the air-water interface was observed to reorganize from circular plates to ring structures by lateral compressions.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.11a
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• pp.97-100
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• 1998

We studied on the ultra thin L-${\alpha}$-DLPC by LB method. The $\pi$-A isotherm of the L-${\alpha}$-DLPC was measured at the air-water interface varying with the compressing speed and amounts of solutions for spreading. The molecular arrangement of deposited films were evaluated by measuring the absorption with the UVspectrometer. And we made structures of metal(Au)/L-${\alpha}$-DLPC/Metal(Au) and examined electron through L-${\alpha}$-DLPC LB films by means of current-voltage(I-V) measurement.

• Applied Chemistry for Engineering
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• v.28 no.1
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• pp.125-131
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• 2017

We report organically functionalized Ag nanoparticles spontaneously form two-dimensional (2D) novel superstructures at the air-water interface. Analysis of the superstructures suggests that the 2D assembly of Ag nanoparticles originates from a subtle interplay between characteristic inter-particle interactions that can be readily controlled by changing the sizes of nanoparticle metal core and surfactants. Such structures have potential uses in nanostructured functional materials, catalysis, and device applications.

• Bulletin of the Korean Chemical Society
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• v.28 no.8
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• pp.1285-1288
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• 2007

Au was electrolessly deposited on polycarbonate (PC) membranes (0.1 μm pores) at the air/water interface. It was found that the Au nanotube dimension can be controlled by adjusting the plating temperature and the solution composition. Interfacial deposition of Au at relatively low temperatures (4℃) produced long nanotubes, which run through the whole membrane thickness with small openings. Increase of plating temperatures resulted in the decrease of nanotube lengths and Au film thicknesses. It was also disclosed that the inside-diameter of Au nanotubes can be controlled with negligible variations in length by changing the composition of a plating solution.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.1200-1202
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• 1993

There are many methods to investigate the physical properties of monolayers formed at the air-water interface. Among them, the displacement current method is appropriate for the investigation of the dynamic behavior of monolayers. The measuring system of displacement current method was constructed at home-made Kuhn type LB deposition apparatus using aluminium plate electrode. The currents induced by the dynamic motion of molecules were measured when the molecules were pressed by barrier. To verify the measuring system, we used 4-octyl -4'-(5-carboxy-pentamethyleneoxy)-azobenzene molecules which has two remarkable variations of surface pressure of monolayer at the air-water interface. We can detect the two peaks of displacement currents which shows that the orientations of molecules are changed greatly at the state of these two remarkable changes of surface pressure.