• Journal of Korean Society for Atmospheric Environment
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• v.23 no.6
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• pp.727-733
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• 2007

In this study, a newly developed biotrickling system, combined with a non-thermal plasma reactor, was investigated to effectively treat gaseous contaminants such as VOCs (Volatile Organic Compounds). Three kinds of non-thermal plasmas (NTPs) such as a rod type dielectric barrier discharge (DBD) plasma, a packed bead type DBD plasma and a gliding arc (GA) plasma, were tested and compared in terms of power consumption. The rod type DBD plasma was selected as one for integration with biotrickling system due to its relatively high VOC removal efficiency, low power consumption and low pressure drop. Toluene and xylene as representatives of VOCs were used as test gases. The experiment results showed that the efficiency of biotrickling system was especially very low at the high gas concentration and high flow rate and the removal efficiencies of VOCs were considerably enhanced in the biotrickling system, when the DBD plasma was worked in front of that even at the high gas concentration and high flow rate.

• Journal of the Korean Society of Propulsion Engineers
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• v.23 no.3
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• pp.1-8
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• 2019

In this study, Arc plasma was employed for the thermal decomposition of nitrous oxide($N_2O$). Conventional ignition systems such as torch, spark, and catalyst systems, have disadvantages in that they are not reliable and do not provide rapid responses. Therefore, this study suggests the plasma application of plasma to overcome the problems of conventional ignition methods. A gas temperature and combustion experiment was carried out to investigate the feasibility to a novel igniter. The gas temperature was measured around $960^{\circ}C$ at 1 g/s, 0.7 A at the nearest wall. In addition, a combustion test was successfully conducted in 3.1 sec after the plasma discharge was initiated with a main flow rate of 10 g/s. The energy consumption for ignition was 1,780 J(574 W).

• The Korean Journal of Ceramics
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• v.2 no.4
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• pp.212-215
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• 1996

This paper focuses the strength and wear resistance of CVD diamond films. The strength of free-standing CVD diamond films synthesized by microwave plasm CVD, DC plasma CVD, RF plasma CVD and arc discharge plasma jet CVD has been measured by three-point bending test. The wear resistance of CVD diamod films has been evaluated by the pin-on-disk type testing. diamond films coated on the base of sintered tungsten carbide pin by hot filament CVD have been rubbed with a sintered diamond disk in muddy water. Volume removed wear of CVD diamond has been compared with stellite, WC alloy and bearing steel.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2004.11a
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• pp.17-18
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• 2004

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.219-219
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• 2009

ceramic metal halide lamps are a subset of high intensity discharge lamps so named because of their high radiance These lamps weak ionized plasma in a fire-resisting but light transmissive wrapping by the corridor of current through atomic and molecular vapors. for commercial applications, For commercial applications, the conversion of electric power to light must occur with good efficiency and with sufficient spectral content throughout the visible (380-800 nm) to permit the light so generated to render colors comparable to natural sunlight. the purpose of this paper is to carry out a study on the variation of ageing time(2000 On/Off[hr]) on the performance of 150W CMH lamps. Experimental results show that the blackening by reacting W(tungsten)with I atomic has been created in the arc tube of an ageing lamp(2000 On/Off[hr]), the arc was unstable, and increased a lamp resistance made lamp voltage increases significantly. Also, Color temperature of the ageing lamp was moved by the losses of Ho with Dy atomics and by recombination of Na with I.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.1
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• pp.79-85
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• 2006

Innovated technique to oxidize pollutants has been developed. The technique for this study uses plasma discharge in 2-phase (Air-Water) and is called Discharged Water Generating (DWG) system. It produces electric arc which generates not only the physical decomposing power against the pollutants but also oxidants to sterilize pollutants depending on the inlet gas species. These physical and chemical products play an important role in COD decrease and biodegradability enhancement. The enhancement of biodegradability for the refractory organic substances in aqueous solution was estimated in this study. Argon discharge reduced NBDCOD of EDTA from 58.7mg/L to 38.8mg/L, but oxygen discharge and ozonation reduced it to 37.74mg/L and 38.73mg/L respectively. Furthermore, Argon discharge changed 1181mg/L of NBDCOD of dye effluent into 606mg/L but oxygen discharge and ozonation changed it into 888mg/L and 790mg/L respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.521-522
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• 2006

In this paper, hybrid air-water discharges were used to develop an optimal condition for providing a high level of water decomposition for hydrogen yield. Electrical and optical phenomena accompanying the discharges were investigated along with feeding gases, flow rates, and point-to-plane electrode gap distance. The primary focus of this experiment was put on the optical emission of the near UV range, with the energy threshold sufficient for water dissociation and excitation. The $OH(A^{2+},'=0\;X^2,"=0$) band's optical emission intensity indicated the presence of plasma chemical reactions involving hydrogen formation. In the gaseous atmosphere saturated with water vapor the OH(A-X) band intensity was relatively high compared to the liquid and transient phases although the optical emission strongly depended on the flow rate and type of feeding gas. In the gaseous phase discharge phenomenon for Ar carrier gas transformed into a gliding arc via the flow rate growth. OH(A-X) band's intensity increased according to the flow rate or residence time of He feeding gas. Reciprocal tendency was acquired for $N_2$ and Ar carrier gases. The peak value of OH(A-X) intensity was observed in the proximity of the water surface, however in the cases of Ar and $N_2$ with 0.5 SLM flow rate peaks shifted to the region below the water surface. Rotational temperature ($T_{rot}$) was estimated to be in the range of 900-3600 K, according to the carrier gas and flow rate, which corresponds to the arc-like-streamer discharge.

• Korean Journal of Optics and Photonics
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• v.13 no.6
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• pp.559-563
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• 2002

We measure the 3-dimensional temporal behavior of the light emitted from the discharge cell of a plasma display panel (PDP) by using a scanned point detecting system. The light signal detected by a PM tube is sent to the oscilloscope, and the oscilloscope is connected to a PC with GPIB. From the resultant temporal behaviors, we could analyze the discharge characteristics of the panel with a Ne-Xe (4%) mixing gas at a 400 torr pressure. The top view of the panel shows that discharge moves from the inner edge of the cathode electrode to the outer cathode electrode, forming an arc shape. The side view of the panel shows that the light is detected up to 150 $\mu\textrm{m}$ up the barrier rib. After a trigger pulse is applied, peak intensity is detected at 730 ns and peak intensity position is located at the center of the ITO electrodes.

• Journal of the Semiconductor & Display Technology
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• v.7 no.2
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• pp.63-67
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• 2008

The MgO protective layer plays an important role in plasma display panels (PDPs). Our previous work demonstrated that the properties of MgO thin film could be improved, which were deposited by ion beam assisted deposition (IBAD). However arc discharge always occurs during the IBAD process. To avoid this problem, oxygen neutral beam assisted deposition (NBAD) is used to deposit MgO thin films in this paper. The energy of the oxygen neutral beam was used as the parameter to control the deposition. The experimental results showed that the oxygen neutral beam energy was effective in determining in F/$F^+$ centers, crystal orientation, surface morphology of the MgO thin film, and the discharge characteristics of AC PDP. The lowest firing voltage $(V_f)$ and the highest secondary electron emission coefficient $(\gamma)$ were obtained when the neutral beam energy was 300 eV.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.12
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• pp.1268-1272
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• 2008

Low temperature plasma applied with partial oxidation is a technique to produce synthesis gas from methane. Low temperature plasma reformer has superior miniaturization and start-up characteristics to reformers using steam reforming or CO$_2$ reforming. In this research, a low temperature plasma reformer using GlidArc discharge was proposed. Reforming characteristics for each of the following variables were studied: gas components ratio (O$_2$/CH$_4$), the amount of steam, comparison of reaction on nickle and iron catalysts and the amount of CO$_2$. The optimum conditions for hydrogen production from methane was found. The maximum Hydrogen concentration of 41.1% was obtained under the following in this condition: O$_2$/C ratio of 0.64, total gas flow of 14.2 L/min, catalyst reactor temperature of 672$^{\circ}C$, the amount of steam was 0.8, reformer energy density of 1.1 kJ/L with Ni catalyst in the catalyst reactor. At this point, the methane conversion rate, hydrogen selectivity and reformer thermal efficiency were 66%, 93% and 35.2%, respectively.