• Transactions on Electrical and Electronic Materials
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• v.12 no.5
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• pp.200-203
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• 2011

In this research, nitrogen (N)-doped zinc oxide (ZnO) thin films have been grown on a sapphire substrate by dielectric barrier discharge (DBD) in pulsed laser deposition (PLD). DBD has been used as an effective way for massive in-situ generation of N-plasma under conventional PLD process conditions. Low-temperature photoluminescence spectra of N-doped ZnO thin films provided near-band-edge emission after a thermal annealing process. The emission peak was resolved by Gaussian fitting and showed a dominant acceptor-bound excitation peak ($A^{\circ}X$) that indicated acceptor doping of ZnO with N. The acceptor binding energy of the N acceptor was estimated to be approximately 145 MeV based on the results of temperature-dependent photoluminescence (PL) measurements.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.6
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• pp.641-648
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• 2008

A plate-type dielectric barrier discharge (DBD) reactor was designed and tested for removal of gaseous toluene. The DBD reactor consisted of 9 parallel plate electrodes, four of which were grounded. An AC voltage of rectangular waveform ($5{\sim}8.5kV$, $60{\sim}1,000Hz$), was applied to the other five electrodes. The gaseous toluene passed through the DBD reactor and its concentration was measured by a real-time gas analyzer. The carbon monoxide (CO) and carbon dioxide ($CO_2$) which were produced by decomposition of toluene in the DBD reactor, were sampled and analyzed by a micro gas chromatography. The maximum toluene removal efficiency was 51.4%.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.4
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• pp.524-533
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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). Aim of this work is to determine design and operating parameters of a hybrid air cleaning system. DBD and ESP(Electrostatic Precipitator) are used as nano particle charger and collector, respectively. Pelletized MnO$_2$ catalyst or activated carbon is used fer ozone decomposition or adsorption material. AC voltage of 7～10 KV(rms) and 60 Hz is used as DBD plasma source. DC - 8 KV is applied to the ESP for particle collection. The overall particle collection efficiency for the hybrid system is over 85 % under 0.64 m/s face velocity. Ozone decomposition efficiency with pelletized MnO$_2$ catalyst or activated carbon packed bed is over 90 % when the face velocity is under 0.4 m/s in dry air.

• Proceedings of the KIPE Conference
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• 2006.06a
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• pp.206-209
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• 2006

At present, the cold cathode fluorescent lamp (CCFL) using mercury lamp has been generally used far liquid crystal backlight source of personal computer and car navigation and so on. This kind of lamp is more excellent on luminance performance and cost. However, the requirements of liquid crystal backlight due to a light source without mercury have been strongly increased from a viewpoint of the actual influence on environmental preservation and environmental recycling. As fluorescent lamp without mercury, Dielectric Barrier Discharge based rare gas fluorescent lamp (DBD-FL) using xenon (Xe) gas has been studied so far. This DBD lamp has no influence on the human body and environmental recycle. Its operating life is long because electrode is out. In this paper, the simulation and experimental results of soft switching high frequency inverter with reverse blocking single switch as a high frequency power supply circuit for DBD-FL using Xe gas are comparatively evaluated and discussed from a practical point of view.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.6
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• pp.617-624
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• 2019

Dielectric barrier discharge (DBD) plasma is one of the promising next generation non-thermal technologies for food sterilization. The present study investigated the effects of DBD plasma on the reduction of most common food-borne pathogenic bacteria (Staphylococcus aureus, Bacillus cereus, Vibrio parahaemolyticus, Salmonella enterica) and sanitary indicative bacteria (Escherichia coli) in the suspension (initial inoculum of approx. 9 log CFU/mL). The bacterial counts were significantly (P<0.05) reduced with the increase in the treatment time (1-30 min) of DBD plasma in the suspension. The D-values (time for 90% reduction) of DBD plasma by first-order kinetics for S. aureus, B. cereus, V. parahaemolyticus, S. enterica, and E. coli were 17.76, 19.96, 32.89, 21.55, and 15.24 min, respectively (R²>0.90). These results specifically showed that 30 min of DBD plasma treatment in > 90% reduction of seafood-borne pathogenic and sanitary indicative bacteria. This suspension study may provide the basic data for use in seafood processing and distribution.

• Journal of Aerospace System Engineering
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• v.11 no.6
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• pp.56-63
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• 2017

Thrust force induced by the dielectric barrier discharge inside of cylinder pipes is measured for various conditions. The input peak-to-peak voltage and frequency are varied from 2 to 9 kVpp and from 5 to 15 kHz, respectively. The height of cylinder is varied from 50 to 100 mm. The results of the measurements show that the magnitude of the generated thrusts increases as the voltage and the frequencies increase. It also shows that the generated thrusts are decreased according to the increase in the height of the cylinder. The cause of the thrust decrease is discussed in terms of energy losses due to the frictions on the wall surface.

• Journal of Surface Science and Engineering
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• v.53 no.5
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• pp.201-206
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• 2020

A SiOxCy(-H) thin film was synthesized by atmospheric pressure dielectric barrier discharge(APDBD), and a SiO₂-like layer was formed on the surface of the film by oxidation treatment using oxygen plasma. Hexamethylcyclotrisiloxane was used as a precursor for the SiOxCy(-H) synthesis, and He gas was used for stabilizing APDBD. Oxygen permeability was evaluated by forming an oxidized SiOxCy(-H) thin film on a PET film. When the single-layer oxidized SiOxCy(-H) film was coated on the PET, the oxygen gas permeability decreased by 46% compared with bare PET. In case of three-layer oxidized SiOxCy(-H) film, the oxygen gas permeability decreased by 73%. The oxygen permeability was affected by the thickness of the SiO₂-like layer formed by oxidation treatment rather than the thickness of the SiOxCy(-H) film. The excellent corrosion resistance was demonstrated by coating an oxidized SiOxCy(-H) thin film on the silver-coated aluminum PCB for light emitting diode (LED).

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2006.05a
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• pp.391-394
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• 2006

This paper presents soft switching zero voltage switching high frequency inverter for rare gas fluorescent lamp using dielectric-barrier discharge phenomenon. The simple high-frequency inverter can completely achieve stable zero voltage soft switching (ZVS) commutation for wide its output power regulation ranges and load variations under its constant high frequency pulse density modulation (PDM) scheme. Its transient and steady state operating principle is originally described and discussed for a constant high-frequency PDM control strategy under a stable ZVS operation commutation, together with its output effective power regulation characteristics-based on the high frequency PDM strategy. The experimental operating performances of this high frequency Inverter are illustrated as compared with computer simulation results and experimental ones. Its light dimming characteristics due to power regulation scheme are evaluated and discussed on the basis of simulation and experimental results. The feasible effectiveness of this high frequency inverter appliance implemented here is proven from the practical point of view.

• Journal of Environmental Science International
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• v.28 no.5
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• pp.495-502
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• 2019

This study was conducted to investigated the possibility of inactivating wilt germs (Fusarium oxysporum f. sp. radicis lycopersici) using Dielectric Barrier Discharge (DBD) plasma in a hydroponic system. Recirculating hydroponic cultivation system for inactivation was consisted of planting port, LED lamp, water tank, and circulating pump for hydroponic and DBD plasma reactor. Two experiments were conducted: batch and intermittent continuous process. The effect of plasma treatment on Total Residual Oxidants (TRO) concentration change, Fusarium inactivation and growth of lettuce were investigated. In the batch experiment, most of the Fusarium was inactivated at a TRO concentration of 0.15 mg/L or more at four-day intervals. There was no change in lettuce growth after two times of plasma treatment for one week. The intermittent continuous experiment consisted of 30-minute, 60-minute, and 90-minute plasma treatment in 2 day intervals and 30-minute treatment a one-day; most of the Fusarium was inactivated only by treatment for 30-minute every two days. However, if inactivation under $10^1CFU/mL$ is required, it will be necessary to treat for 60 minutes in 2 day intervals. The plasma treatment caused no damage to the lettuce, except the 30 min plasma treatment ay the one-day interval. It was considered that the residual TRO concentration was higher than that of the other treatments.

• Korean Journal of Materials Research
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• v.33 no.4
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• pp.115-123
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• 2023

In this paper, we report and discuss the semi-permanently hydrophilic (SPH) treatment of polyester fabric using plasma polymerization and oxidation based on atmospheric pressure dielectric barrier discharge (APDBD) technology. SiO_xC_y(-H) was coated on polyester fabric using Hexamethylcyclotrisiloxane (HMCTSO) as a precursor, and then plasma oxidation was performed to change the upper layer of the thin film to SiO₂-like. The degradation of hydrophilicity of the SPH polyester fabrics was evaluated by water contact angle (WCA) and wicking time after repeated washing. The surface morphology of the coated yarns was observed with scanning electron microscopy, and the presence of the coating layer was confirmed by measuring the Si peak using energy dispersive x-ray spectroscopy. The WCA of the SPH polyester fabric increased to 50 degrees after 30 washes, but it was still hydrophilic compared to the untreated fabric. The decrease in hydrophilicity of the SPH fabric was due to peeling of the SiO_xC_y(-H) thin film coated on polyester yarns.