• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.383-384
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• 2003

오존은 산업적으로 널리 활용되고 있으며 특히, 매우 넓은 환경공학적 응용분야를 가지고 있다. 오존의 산업적 적용은 1900년대 초부터 음용수 처리를 위해 시작되었으며 현재까지 폐수처리, 화학물질 합성, 재료의 부식 정도 측정, 수영장 소독, 치료용 목적, 냉각수 살균, pulp bleaching, 악취 및 대기 오염물질 처리 등의 광범위한 산업적 응용분야를 가지고 있다. 오존을 생성시키기 위한 대표적인 공정으로는 무성방전(dielectric barrier discharge, DBD) 공정, 전기 분해법(electrolysis), 자외선 조사법(UV irradiation)을 들 수 있으며 가장 널리 활용되고 있는 공정은 1857년 Simens에 의해 개발된 DBD 공정이다. (중략)

• Journal of the Semiconductor & Display Technology
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• v.15 no.2
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• pp.26-31
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• 2016

The Townsend to glow discharge mode transition was investigated in the dielectric barrier discharge (DBD) helium plasma source which was powered by 20 kHz / $4.5 kV_{rms}$ high voltage at atmospheric pressure. The spatial profile of the electric field strength at each modes was measured by using the intensity ratio method of two helium emission lines (667.8 nm ($3^1D{\rightarrow}2^1P$) and 728.1 nm ($3^1S{\rightarrow}2^1P$)) and the Stark effect. ICCD images were analyzed with consideration for the electric field property. The Townsend discharge (TD) mode at the initial stage of breakdown has the light emission region located in the vicinity of the anode. The electric field of the light emitting region is close to the applied field in the system. Immediately, the light emitting region moves to the cathode and the discharge transits to the glow discharge (GD) mode. This mode transition can be understood with the ionization wave propagation. The electric field of the emitting region of GD near cathode is higher than that of TD near anode because of the cathode fall formation. This observation may apply to designing a DBD process system and to analysis of the process treatment results.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1272-1275
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• 2008

We present the development of dry etch process for the liquid crystal display (LCD) fabrication using a dielectric barrier discharge (DBD) system at atmospheric pressure. In this experimental work, the dry etch characteristics and the electrical properties of thin film transistor are evaluated by using the scanning electron microscopy and electric probe, and TFT-LCD panel ($300\;mm\;{\times}\;400\;mm$) is manufactured with the application of the amorphous silicon etch step in the 4 mask and 5 mask processes.

• Proceedings of the Korean Vacuum Society Conference
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• 2008.08a
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• pp.280-280
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• 2008

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.251-252
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• 2005

Streamer mode plasma is generated in the water DBD. Driving frequency is an important parameter for improving the discharge efficiency. With the optimum frequency, the decomposition of EDTA in the water is effectively preceded in the water-DBD plasma.

• The Korean Journal of Food And Nutrition
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• v.30 no.2
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• pp.290-296
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• 2017

In this study, using the surface dielectric barrier discharge (DBD) produced at atmospheric pressure to improve the physiological activities of quercetin was investigated. Quercetin (at 200 ppm) was treated using air DBD with an input power of 250 W. The tyrosinase inhibition effect and total phenolic content of quercetin increased from 38.96 to 91.58% and from 134.53 to 152.93 ppm, respectively, after 20 min of plasma treatment. The antioxidant activity of quercetin treated for 20 min in the lipid models was higher than that of quercetin treated for 0, 5, and 10 min. Furthermore, plasma-treated quercetin exhibited antimicrobial activity against Listeria monocytogenes, Salmonella Typhimurium, and Staphylococcus aureus, whereas activity was not shown in the control. Structural modifications of the quercetin molecule induced by plasma might be responsible for the improvements in its physiological activity. These results indicate that DBD plasma could be used to enhance the physiological activity of quercetin for various applications in food.

• Journal of Korean Society of Water and Wastewater
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• v.34 no.1
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• pp.75-83
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• 2020

This study investigated the degradation characteristics and biodegradability of phenol, refractory organic matters, by injecting MgO and CaO-known to be catalyst materials for the ozonation process-into a Dielectric Barrier Discharge (DBD) plasma. MgO and CaO were injected at 0, 0.5, 1.0, and 2 g/L, and the pH was not adjusted separately to examine the optimal injection amounts of MgO and CaO. When MgO and CaO were injected, the phenol decomposition rate was increased, and the reaction time was found to decrease by 2.1 to 2.6 times. In addition, during CaO injection, intermediate products combined with Ca²⁺ to cause precipitation, which increased the COD (chemical oxygen demand) removal rate by approximately 2.4 times. The biodegradability of plasma treated water increased with increase in the phenol decomposition rate and increased as the amount of the generated intermediate products increased. The biodegradability was the highest in the plasma reaction with MgO injection as compared to when the DBD plasma pH was adjusted. Thus, it was found that a DBD plasma can degrade non-biodegradable phenols and increase biodegradability.

• Journal of Korean Society of Water and Wastewater
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• v.33 no.4
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• pp.243-250
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• 2019

This objective of this study was to investigate the degradation characteristics of phenol, a refractory substance, by using a submerged dielectric barrier discharge (DBD) plasma reactor. To indirectly determine the concentration of active species produced in the DBD plasma, the dissolved ozone was measured. To investigate the phenol degradation characteristics, the phenol and chemical oxygen demand (COD) concentrations were evaluated based on pH and the discharge power. The dissolved ozone was measured based on the air flow rate and power discharged. The highest dissolved ozone concentration was recorded when the injected air flow rate was 5 L/min. At a discharge power of 40W as compared to 70W, the dissolved ozone was approximately 2.7 - 6.5 times higher. In regards to phenol degradation, the final degradation rate was highest at about 74.06%, when the initial pH was 10. At a discharged power of 40W, the rate of phenol decomposition was observed to be approximately 1.25 times higher compared to when the discharged power was 70W. It was established that the phenol degradation reaction was a primary reaction, and when the discharge power was 40W as opposed to 70W, the reaction rate constant(k) was approximately 1.72 times higher.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.1678-1683
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• 2003

DBD(Dielectric Barrier Discharge) plasma in air is well established for the production of large quantities of ozone and is more recently being applied to aftertreatment processes for HAPs(Hazardous Air Pollutants). Although DBD high electron density and energy, its potential use as nano and sub-micron sized particle charging are not well known. Aim of this work is to determine design and operating parameters of a two-stage ESP with DBD. DBD and ESP are used as particle charger and precipitator, respectively. We measured particle precipitation efficiency of two-stage ESP and estimated ozone decomposition of both pelletized $MnO_2$ catalyst and pelletized activated carbon. To examine the particle precipitation efficiency, nano and sub-micron sized particles were generated by a tube furnace and an atomizer. AC voltage of $7{\sim}10$ kV(rms) and 60 Hz is used as DBD plasma source. DC -8 kV is applied to the ESP for particle precipitation. The overall particle collection efficiency for the two-stage ESP with DBD is over 85 % under 0.64 m/s face velocity. Ozone decomposition efficiency with pelletized $MnO_2$ catalyst or pelletized activated carbon packed bed is over 90 % when the face velocity is under 0.4 m/s in dry air.

• Journal of Industrial Convergence
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• v.21 no.7
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• pp.83-92
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• 2023

The bullet shape of the plasma jet using the atmospheric-pressure dielectric barrier discharge method changes depending on the applied fluid rate and the intensity of the electric field. This changes appear as a difference in spectral distribution due to a difference in density of the DBD plasma jet. It is an important factor in utilizing the plasma device that difference between the occurrence of active species and the intensity through the analysis of the spectrum of the generated plasma jet. In this paper, a plasma jet generator of the atmospheric pressure volume DBD method using Ar gas was make a prototype in accordance with the proposed design method. The characteristics jet fluid rate analysis of Ar gas was accomplished through simulation to determine the dependence of flow rate for the generation of plasma jets, and the characteristics of plasma jets using spectrometers were analyzed in the prototype system to generate optimal plasma jet bullet shapes through MFC flow control. Through the design method of the proposed system, the method of establishing the optimal plasma jet characteristics in the device and the results of active species on the EOS were verified.