• Applied Chemistry for Engineering
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• v.27 no.6
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• pp.627-632
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• 2016

Ethyl methacrylate (EMA) monomer coupling onto the polyvinylidene fluoride (PVDF) film surface was attempted to enhance the interfacial adhesive force between PVDF-polyvinyl chloride (PVC) bilayer films via dielectric barrier corona discharge. The interfacial forces were quite enhanced when PVDF films were treated by corona discharge in an EMA 1% atmosphere. The contact angle of PVDF films decreased due to corona treatment. X-ray photoelectron spectroscopy (XPS) analysis showed that the carbon and oxygen content of the PVDF film surface increased with corona discharge while the fluoride content decreased. The curve fitting of XPS $C_{1s}$ peaks revealed that the non-polar C-C bonded carbon and oxygen-bonded carbon increased gradually with corona treatment, while the fluorine-bonded carbon decreased.

• 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.

• Journal of the Speleological Society of Korea
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• no.76
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• pp.37-42
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• 2006

The Dielectric Barrier Discharge (DBD) is a nonequilibrium gas discharge that is generated in the space between two electrodes, which are separated by an insulating dielectric layer. The dielectric layer can be put on either of the two electrodes or be inserted in the space between two electrodes. If an AC or pulse high voltage is applied to the electrodes that is operated at applied frequency from 50Hz to several MHz and applied voltages from a few to a few tens of kilovolts rms, the breakdown can occur in working gas, resulting in large numbers of micro-discharges across the gap, the gas discharge is the so called DBD. Compared with most other means for nonequilibrium discharges, the main advantage of the DBD is that active species for chemical reaction can be produced at low temperature and atmospheric pressure without the vacuum set up, it also presents many unique physical and chemical process including light, heat, sound and electricity. This has led to a number of important applications such as ozone synthesizing, UV lamp house, CO2 lasers, et al. In recent years, due to its potential applications in plasma chemistry, semiconductor etching, pollution control, nanometer material and large area flat plasma display panels, DBD has received intensive attention from many researchers and is becoming a hot topic in the field of non-thermal plasma.

• Journal of Environmental Science International
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• v.23 no.3
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• pp.369-378
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• 2014

Effect of improvement of the dielectric barrier discharge (DBD) plasma system on the inactivation performance of bacteria were investigated. The improvement of plasma reactor was performed by combination with the basic plasma reactor and UV process or combination with the basic plasma reactor and circulation system which was equipped with gas-liquid mixer. Experimental results showed that tailing effect was appeared after the exponential decrease in basic plasma reactor. There was no enhancement effect on the Ralstonia Solanacearum inactivation with combination of basic plasma process and UV process. The application of gas-liquid mixing device on the basic plasma reactor reduced inactivation time and led to complete sterilization. The effect existence of gas-liquid mixing device, voltage, air flow rate (1 ~ 5 L/min), water circulation rate (2.8 ~ 9.4 L/min) in gas-liquid mixing plasma, plasma voltage and UV power of gas-liquid mixing plasma+UV process were evaluated. The optimum air flow rate, water circulation rate, voltage of gas-liquid mixing system were 3 L/min, 3.5 L/min and 60 V, respectively. There was no enhancement effect on the Ralstonia Solanacearum inactivation with combination of gas-liquid mixing plasma and UV process.

• Journal of Environmental Science International
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• v.25 no.7
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• pp.905-916
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• 2016

The characteristics of phenol removal and $UV_{254}$ matters variance were investigated and compared by the variation of operating factors (NaCl concentration, air flow rate, initial phenol concentration) in electrochemical reaction (ER) and dielectric barrier discharge plasma reaction (DBDPR), respectively. The phenol removal rate was shown as $1^{st}$ order both in ER and DBDPR. Also, the absorbance of $UV_{254}$ matters which means aromatic intermediates was analyzed to investigate the complete phenol degradation process. In ER, the phenol degradation and aromatic intermediates production rates increased by the increase of NaCl concentration. However, in DBDPR, the variation of NaCl concentration had no effect on the degradation of phenol and $UV_{254}$ matters. Air flow rate had a little effect on the removal of phenol and the variation of $UV_{254}$ matters in ER. The phenol removal rate in ER was a little higher than that in DBDPR. The produced $H_2O_2$ and $O_3$ amounts in ER were 2 times and 10 times higher than those in DBDPR. The chlorine intermediates ($ClO_2$ and free chlorine) were produced in ER, however, they were not produced in DBDPR.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.78-82
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• 2003

For the decomposition of laundry wastewater containing Fe-EDTA produced from the steam generators in nuclear power plants, Supercritical Water Oxidation (SCWO) Process, Photocatalytic Oxidation (PO) Process, and Dielectric Barrier Discharge (DBD) Atmospheric Pressure Plasma Process were evaluated. Even though EDTA was converted over 99.98 % by the SCWO process, it was estimated that the countermeasure against corrosion of the equipment should be reinforced for the process stability. It was considered that the PO process is not appropriate for the decomposition of high concentrated laundry wastewater since the conversion ratio of EDTA was around 10 %. Finally, High efficiency of the decomposition of organic matter (methylene blue) was obtained using DBD process even low energy was supplied. However there is still room for the evaluation of EDTA decomposition in order that the DBD process should be applied for the field samples.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2182-2185
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• 1999

In this experimental study we propose the double dielectric barrier discharge(DDBD) reactor to produce as high an electric field as possible. DDBD reactor is designed to remove $NO_x$ at atmospheric pressures from the moving pollution source such as diesel automobile DDBD reactor consisted of two cylinder glass tubes arranged so that the gas flow was directed between the two tubes. Inside of the inner tube was filled with small metal beads and outside of the inner tube was wounded with stainless wire to form the electrode. The outer tube was surrounded by an aluminum foil In this reactor there are three electrodes, i.e. metal bead(C), helical wire(I) and aluminum foil(0). By using DDBD reactor we will report some interesting results of treatment of the gas which is the dilute mixtures of NO in N2. And then we compared thee results with the results of cylinder-wire(CW) which is one of popularly used reactor in non-thermal plasma applications.

• Journal of the Korean institute of surface engineering
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• v.44 no.2
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• pp.50-54
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• 2011

Hydrophobic a-C:F film was coated on polycarbonate film with $CF_4$, $C_2F_6$ and HFC ($C_2F_4H_2$) gas in helium discharge generated by 5~100 kHz AC power supply at atmospheric pressure and room temperature. The highest water contact angle of the a-C:F film formed with $He/C_2F_6$ mixed gas is $155^{\circ}$. X-ray photoelectron spectrum showed that there was 40% of C-$CF_3$ bond at the surface of the super hydrophobic film. The contact angle and deposition rate were decreased with increasing substrate temperature. The contact angle was generally increased with the surface roughness of the film. The contact angle was high when the surface microstructure of the film was fine and sharp at the similar roughness and chemical composition of the surface.

• Journal of the Korean institute of surface engineering
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• v.48 no.5
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• pp.245-252
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• 2015

In recent years, the cleaning and activation technology of surfaces using atmospheric plasma as well as the deposition technology for coating using atmospheric plasma have been demonstrated conclusively and drawn increasing industrial attention. Especially, due to the simplicity, the technology using atmospheric plasma enhanced chemical vapor deposition has been widely studied from many researchers. The plasma source type commonly used as the stabilization of diffuse glow discharges for atmospheric pressure plasma enhanced chemical vapor deposition pressure is the dielectric barrier discharge. In this review paper, some kinds of modified dielectric barrier discharge type will be presented. And, the characteristics of silicon based compound such as SiOx and SiNx deposited using atmospheric plasma enhanced chemical vapor system will be discussed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.6
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• pp.910-916
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• 2022

The purpose of this study is to evaluate the effect of underwater non-thermal dielectric barrier discharge plasma (DBD plasma) on the sterilization of three types of pathogenic bacteria that cause diseases in freshwater fish and the reduction of a tetracycline antibiotics. This experiment was conducted in the DBD plasma generator, and the voltages used to generate plasma were 11.6 kV and 23.1 kV. The measurement intervals were 0, 1, 5, 10 and 15 min. As a result of DBD plasma treatment, Aeromonas hydrophila, Edwardsiella tarda and Pseudomonas fluorescens were removed 93-99% after 5 min at 23.1 kV, and the tetracycline antibiotics were reduced 70-95% after 15 min at 23.1 kV. In this study, as a result of treating the effluent with DBD plasma at a fish farm where the medicinal bath was conducted with oxytetracycline-HCl (OTC-HCl) products, OTC-HCl decreased by 62% after 10 min at 23.1 kV.