• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1544-1546
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• 2003

In this study, composite materials were put to dry interfacial treatment by use of plasma technology. It has been presented that the optimum parameters for the best wettability of the samples at the time of generation of plasma were oxygen atmosphere, 0.1 torr of system Pressure, 100 W of discharge power, and 3 minutes of discharge time. The decrease in surface potential of charged samples by corona discharge indicates that the amount of accumulated electrical charges reduces and the charges that have been injected lessen rapidly when the duration of UV irradiation increases. The surface resistivity and the tensile strength of plasma treated samples, a longer UV irradiation time resulted in decreased insulation.

• Proceedings of the KIEE Conference
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• 1996.07c
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• pp.1910-1912
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• 1996

This paper presents the results of laboratory experimentals to remove $SO_2$ and $NO_x$ by a pulsed corona discharge in the wire-plate reactor. A rotating spark gap switch was used to generate the pulse by chewing the dc high voltage. Repetition frequency of the pulse was 60Hz and rising time of 50ns. The photo pictures of positive streamer corona taken by ICCD camera, pulse voltage and current were measured using a digital oscilloscope. Simultaneous effects of $C_{2}H_{4}$ injection and heterogeneous chemical reactions on nonthermal plasma process to remove $SO_2$ and $NO_x$ from flue gas were investigated in the present study

• Journal of the Korean Society of Combustion
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• v.8 no.1
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• pp.9-16
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• 2003

Carbon soot emission from combustion processes, especially from diesel engines, is a subject of growing concern since soot is known to seriously affect human health. Efforts have been made to oxidize soot particles utilizing Non-Thermal Plasma(NTP) techniques. When oxygen is carried into a plasma device, electrons generated by the plasma dissociate the oxygen, resulting in the formation of oxygen atoms. These highly activated atoms, called O radicals, are known as strong oxidizing agent. This paper presents concentration variations of CO and $CO_2$ at the exit of the plasma device, resulting from the soot oxidation by O radicals, with variations of inlet oxygen concentration, gas temperature, and gas flow rate. Based on the data, Arrehenious rate constants of reactions between C(s)+O and C(s)+O+O were proposed.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.12
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• pp.77-82
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• 2015

Ozone is a powerful disinfectant and oxidizing agent, and it is used in a wide range of applications, such as waste water treatment, food processing, etc.. There is also a great potential of using ozone in new emerging medical applications, such as ozone dentistry and ozone oxygen therapy. For these purposes, simple, small, compact and efficient sources of ozone are needed. In this study, in order to increase the current-voltage range of the discharge and to avoid the overheating of the gas in the ozonizer we suggested ozonizer of injection needle and plate electrode type(INP Type) with the gas through the needle. A ozonizer of INP type have been investigated by focusing on ozone concentration and yield according to flow rates and Gap of two electrodes. The results of studies of ozone production for DC corona discharge in oxygen at atmospheric pressure about the ozonizer of INP type. The ozone concentration and the generation yield increased as the gap of two electrodes and gas flow were decreased. Also, when the gap of two electrodes and gas flow with no change, the ozone concentration and generation yield each have variation of direct proportion and inverse proportion with discharge voltage.

• Journal of the Korean Society of Safety
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• v.15 no.2
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• pp.92-96
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• 2000

In this experiment, we studied about concentration characteristics of $NO_x$ and generation of ozone in the reactor of corona discharge type by using mixed gas of $NO/N_2$ and $N_2/O_2$. In the case of the initial NO concentration increased, decrease rate of NO concentration was weakened and discharge input power of minimum NO concentration became high. When NO concentration was high, NO decomposition limit was appeared. And NO reduction rate was decreased, when initial NO concentration and discharge input power increased. When discharge input power was 5W, we could know the most proper energy value for treatment of NO. When the concentration of initial NO increased, generation of ozone decreased and in the case of same concentration of NO, according to discharge input power increase, generation of ozone increased.

• Composites Research
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• v.23 no.3
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• pp.13-18
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• 2010

One of the biggest challenges in the nano-field is how to effectively disperse nano-scale particles, especially CNTs, which are strongly agglomerated by intermolecular van der Waals forces. This study suggests a new method, discharge flocking, in order to disperse nano-scale particles effectively, which combines corona discharge phenomenon and a traditional electrostatic flocking process. In order to evaluate the discharge flocking process, composite specimens were fabricated by the process and RFI(resin film infusion) process, and then the mechanical and electrical properties of the specimens were measured and compared. Moreover, the evaluation of gas discharge effect on the CNTs and epoxy was performed to compare the mechanical and electrical properties of the composite specimens including the plasma treated CNTs. The experimental results showed that the electrical and mechanical properties of the specimens fabricated by the discharge flocking process were similar to those of the RFI process. In addition, plasma treated CNTs were not affected by gas discharge during the discharge flocking process.

• Textile Coloration and Finishing
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• v.9 no.3
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• pp.1-9
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• 1997

Plasma techniques permit modification of the surface layers of the substrate while maintaining its bulk properties. The use of plasma treatment on textile fibers and fabrics is very limited, however, the limitations, plasma treatments have been used to modify surface properties of textiles. In this study, multifunctional finish was performed by corona discharge technique for surface functionalization. Electron spectroscopy for chemical analysis(ESCA) was used to determine the ratios of carbon, oxygen, nitrogen, and phosphor at a 20$\AA$ sampling depth. K/S value and limiting oxygen index(LOI) value were used to obtain information on the effect of the finished fabrics. The mechanism of the flame retardancy was analyzed by the thermogravimetry-and the residue number. In ESCA, relative N1s intensity increased in case of mixtrure. The flame retardancy of the polyester and polyester/cotton fabrics treated with JA-6034 and JA-6050 was found to be operative mainly in the condensed phase mechanism. The multifunctional finish was better effect for the post treated finish agent.

• Journal of the Korean Vacuum Society
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• v.15 no.2
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• pp.117-138
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• 2006

Plasmas can be made by electrical discharge on earth. Most of the plasmas on earth have been generated in low pressure environments where the pressure is less than one millionth of the atmospheric pressure. However, there are many plasma applications which require high pressure plasmas. Therefore, scientists start research on plasma generation at high pressure to avoid use of expensive vacuum equipments. Large-volume inexpensive plasmas are needed in the areas of material processing, environmental protection and improvement, efficient energy source and applications, etc. We therefore developed new methods of plasma generations at high pressure and carried out research of applying these plasmas to high tech industries representing 21 century. These research fields will play pivotal roles in material, environmental and energy science and technology in future.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.152-152
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• 2012

In this work we measured electron temperature and electron density of a microplasma by optical emission spectroscopy. The plasma is generated from a small discharge gap of a microwave parallel stripline resonator (MPSR) in Helium at atmospheric pressure. The microwave power supplied for this plasma source from 0.5 to 5 watts at a frequency close to 800 MHz. The electron temperature and electron density were estimated through Collisional-radiative model combined with Corona-equilibrium model. The results show that the electron density and temperature of this plasma in the case small discharge gap width are higher than that in larger gap width. The diagnostic techniques and associated challenges will be presented and discussed.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1574-1575
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• 2011

The application of a pulsed power system is being extended to an environmental and industrial field. The non-destructive gaseous pollutants from industrial plants such as power generation plants and incinerators can be processed by applying high voltage pulses with a fast rising time (a few nanoseconds) and short duration (nano to microseconds) in a pulsed corona discharge reactor. The pulsed plasma generator with a triggered switch has been developed. Its corona current in load can be adjusted by applied voltage and repetition rate. We investigated the performance of the pulsed plasma generator by analyzing the concentration of ozone in small reactor. This paper describes the electrical characteristics of the pulse generator with a voltage of 30 kV at repetition rate of 50 PPS. In addition, we briefly discuss a configuration of the system and initial test results.