• Journal of the Korean Society of Combustion
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• v.4 no.1
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• pp.27-38
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• 1999

We constructed a wire-cylinder type pulsed corona discharge system for $NO_x$ removal, which was operated in room temperature. A emission spectrometer was built with a boxcar averager and monochrometer equipped with photo-multiplier tube detector. The sensitivity of the emission spectrometer was greatly improved by synchronizing the emission spectrometer with pulsed corona discharge system using a triggered spark-gap switch. $N_2$ spectrum($c^3{\Pi}_u{\rightarrow}X^1{\Sigma}_g{^+}$) was measured in the range of 300 - 450 nm and oxidizing OH radical emission($A^2{\Sigma}^+{\rightarrow}X^2{\Pi}$) was measured in case $N_2$ was supplied with water bubbling. As wet gas composition of inlet $N_2$ supplied in the discharge system increased, the intensity of OH emission was increased and saturated at wet gas composition 50%. We also investigated additive effect of $C_2H_4,\;H_2O,\;H_2O_2$ on the intensity of OR emission and $NO/NO_2/NO_x$ reduction and analysed the related reaction mechanism in corona discharge process. $H_2O_2$ additive increased the intensity of OH emission and $NO/NO_x$ reduction.

• Journal of Adhesion and Interface
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• v.7 no.3
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• pp.26-33
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• 2006

Nylon fabrics were corona treated with different current intensity (5, 10, 15, 20 A) and feeding speed (5, 10, 15 m/min). We confirmed the change of nylon fabrics surface using X-ray diffraction apparatus, scanning electron microscopy (SEM) and X-ray photoelectron spectrometer (ESCALAB). And the change of physical properties through measuring the tensile strength, tear strength, bonding and wet bonding strength. Thermosetting reactive polyurethane hot melt adhesive was used in the adhesion of nylon fabrics. Functional groups were introduced on nylon fabric surface by treating the fabrics in air atmosphere with corona discharge, and the result adhesion was improved. Bonding strength of the nylon fabric treated with corona was increased with increasing current intensity and decreasing feeding speed.

• Journal of the Korean Institute of Telematics and Electronics T
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• v.36T no.3
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• pp.72-78
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• 1999

The frequency characteristics of surface corona discharge from the electrodes on the ceramic substrate ozonator were investigated. The frequency characteristics of dark current were compared with that of corona discharge. Switching frequency which was the fraction of resonant frequency was found to be effective for corona discharge. This is regarded to distort the electric field distribution on the discharge plate which is essential for corona discharge. The measurement showed the efficiency of 28mg/W ozone generation when the switching frequency was 1/5 of the resonant frequency.

• Textile Coloration and Finishing
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• v.8 no.6
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• pp.65-72
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• 1996

Polyester(PET) fabrics were treated by corona discharge equipment with the small amount of flame retardants to enhance flame retardancy. The surface properties of corona discharged fabrics were investigated using water penetration time, SEM, ESCA, and TGA. When corona discharge was applied to PET fabrics, the flame retardants were evenly distributed. As a result, the oxygen-containing functional groups were produced, and the LOI value increased. Thermogravimetric analysis indicated that the flame retardancy was operative by gas-phase mechanism.

• Bulletin of the Korean Chemical Society
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• v.34 no.3
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• pp.763-767
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• 2013

We resolved the controversial assignments of the visible vibronic bands observed from corona discharge of 1,2,3-trimethylbenzene. The vibronic bands belonging to the jet-cooled 2,6-dimethylbenzyl radical were clearly identified from the spectrum observed from corona discharge of 2,6-dimethylbenzyl chloride. After subtracting the bands of the 2,6-isomer from the spectrum observed from corona discharge of 1,2,3-trimethylbenzene, the vibronic bands of the 2,3-isomer were also identified. By comparing data with the known vibrational data of 1,2,3-trimethylbenzene and the results of ab initio calculations, we determined the electronic energies of the $D_1{\rightarrow}D_0$ transitions and vibrational mode frequencies in the ground electronic states of the 2,3-and 2,6-dimethylbenzyl radicals.

• Proceedings of the KIEE Conference
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• 1984.07a
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• pp.226-229
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• 1984

A novel high intensity charging device has been developed for the control of the submicron particles, such as the diesel soot particulates, which are very hard to charge highly by any means of the conventional charging device. Having new corona electrodes of a multineedle disk with the corona field-control electrodes in the outer-cylinder electrode, extremely intense and stable coronas on there sharp points expanding both radially and axially are established in the corona charging region between the multi-corona -needles and an outer-cylinder electrode. As a result, the maximum corona field intensity and current density of the charging device of the standard one on soot load in laboratory tests have been 8.5KV/cm(E=$2V_m$/D(1nD/d)) and $6.5{\mu}A/cm^2$ which enhance greatly the charging of soot particles about several 100 times higher than those obtained in conventional cylinder precipitators.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.52 no.9
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• pp.388-394
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• 2003

Many toxic pesticides as aqueous-base sprays are dispensed for protection of food crops from pests into farm fields. When dispensed with conventional nozzles, a large portion of the spray is often lost by airborne drifts of droplets away and lack of deposition onto the plants due to rapid gravitational settling of droplets to the soil beneath. And target deposition efficiencies poorer than 20％ are often encountered in agricultural pesticides. An electrostatic spraying technology offers a very favorable means to increasing pesticides droplets deposition onto biological surfaces of living crops. In this paper a corona type spray nozzle, utilizing a set of corona charging devices and a pulsed droplet-charging voltage applied, has been proposed and tested its potential experimentally. As a result, it exhibits a large current deposition of aqueous pesticide sprays on the sensing target, which, however, promise to be as one of the effective electrostatic spraying nozzle.

• Proceedings of the KIEE Conference
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• 2000.07e
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• pp.22-25
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• 2000

Time dependent ozone generation characteristics of some oxide layers grown by ozone on the surface of corona discharge wires have been investigated experimentally in air ambience. Four wires of stainless steel, iron, silver and copper were used for the corona discharge wire of an ozone generator. And the effect of the metal oxide layers on ozone generation was studied and the contamination morphology of each layers was characterized. With the SEM images and the EDS spectra, it was found that all the surface of the corona wire were oxidized by the generated ozone and contaminated by airborne particles through the gradient force. As a result, the morphology and the electrical property of metal oxide layer grown on corona wire surface influenced on ozone generation characteristics i.e. discharge mechanisms.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.38 no.8
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• pp.650-657
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• 1989

The conversion efficiency of an ozone generator can be significantly improved by modifying the discharge electrode of a helical strip line rod-to-cylinder type ozone generator to a pyramid-project-embossed rod, and by using a pulse corona discharge. Parametric studies have been carried out to obtain optimum values of peak pulse voltage, pulse forming capacitance, feeder cable and ozone generator capacitance, interelectrode spacing and corona tip density of ozone generator, and feed air flow rate and temperature. The generated ozone concentration was very dependent upon the value of pulse forming capacitance, feeder cable and ozone generator capacitance, and corona tip density. Maximum conversion efficiency was obtained with a pulse forming capacitance of about 500pF, 75pF matched feeder cable and ozone generator, and a corona tip density of 16mm. When operated at optimum values, ozone yield of 79, 99, 80 g/KWh for the different interelectrode type ozone generators tested were obtained, which are approximately 30% higher than that of an industrial ozone generator.

• 전기의세계
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• v.19 no.6
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• pp.18-25
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• 1970

The object of this project is to manifest the mechanism of deterioration phenomena for dielectrics causing corona discharge and applies it for determine the standard corona detection technique. As the results, we observed that corona discharges may occur more strongly around cylindrical shape electrode in air than hemisphere shape electrode in vacuum, so that it depends on effects such as shape of the electrode, moisture, surface coditions, etc. According to observed the deterioration of dielectrics takes place in following stages. At first the attacked surface by an electron avalanche is uniformly eroded; then pits are formed; after that sharp channels are formed which lead to break-down as a treeing. The test are accelerated with higher frequencies by the cylindrical bar shape electrode in the pulse stright detection method more sensitive than Lissajous patterns. Lissajous patterns detection method is simple but usually insensitive and has disadvantage that the magnitude of the individual discharge is not measured.