• Textile Coloration and Finishing
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• v.26 no.3
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• pp.201-208
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• 2014

The high value-added functionality for synthetic fiber can be considered through a plasma enhanced treatment. In this study, PET(Polyethyleneterephthalate) was treated with a glow plasma and corona treatment. Surface characteristics of treated fabric were investigated using electron scanning microscopy(SEM), contact angle, X-ray photoelectron spectroscopy(XPS), tensile and adhesion strength. It was found that the contact angle showed $85.5^{\circ}$ for untreated fabric, $0^{\circ}$ for plasma and corona treatment at the condition of 200W for 7min. By XPS analysis, atomic ratio of O 1s/C 1s was increased from 0.27 to 0.43 by glow plasma and 0.27 to 0.41 by corona treatment at 200W for 7min, respectively. Glow plasma and corona treatment did not significantly change the tensile strength of PET fabric. Adhesion strength showed a substantial enhancement for the surface treated with the glow plasma, while corona treatment was adversely affected.

• Electrical & Electronic Materials
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• v.8 no.4
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• pp.504-508
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• 1995

The purpose of this research is to study on characteristics of corona ignitor which was designed for ignition of plasma, used at hard coating, surface treatment and thin film preparation, at high pressure. Corona ignitor composed of hollow type inner electrode and ring type external electrode. Though corona voltage increased with increasing distance between electrodes, corona discharge can be controlled stably. The gas flow in hollow type inner electrode and the construction between electrodes affect a length of corona flame and corona phenomenon. It is possible to ignite the . plasma, usually generated at low pressure(10 Torr), at high pressure(100 Torr) by corona ignitor.

• Applied Chemistry for Engineering
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• v.25 no.4
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• pp.386-391
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• 2014

Atmospheric-pressure nonthermal corona discharge plasma was applied to the sterilization of biologically contaminated scoria powder. Escherichia coli (E. coli) culture solution was uniformly sprayed throughout the scoria powder for artificial inoculation, which was well mixed to ensure uniformity of the batch. The effect of the key parameters such as discharge power, treatment time, type of gas and electrode distance on the sterilization efficiency was examined and discussed. The experimental results revealed that the plasma treatment was very effective for the sterilization of scoria powder; 5-min treatment at 15 W could sterilize more than 99.9% of E. coli inoculated into the scoria powder. Increasing the discharge power, treatment time or applied voltage led to an improvement in the sterilization efficiency. The effect of type of gas on the sterilization efficiency was in order of oxygen, synthetic air (20% oxygen) and nitrogen from high to low. The inactivation of E. coli under the influence of corona discharge plasma can be explained by cell membrane erosion or etching resulting from UV and reactive oxidizing species (oxygen radical, OH radical, ozone, etc.), and the destruction of E. coli cell membrane by the physical action of numerous corona streamers.

• Journal of the Semiconductor & Display Technology
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• v.13 no.1
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• pp.7-12
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• 2014

In this study, we investigate the effects of corona-discharge pre-treatment on the properties of carbon nanotubes (CNTs) which are used as flexible transparent electrodes. The CNTs are deposited on PET (polyethylene terephthalate) substrates using a spray coating method. Prior to the deposition of CNTs, the PET substrates are corona-treated by varying the feeding directions of the PET substrate and the numbers of treatments. The variations in the surface morphologies and roughnesses of the PET substrates due to corona-treatment are characterized via atomic force microscopy (AFM). Dynamic contact angles (DCAs) of the corona-treated PET substrates are measured and analyzed as functions of the treatment conditions. Also, the sheet resistances and visible-range transmittances of the CNTs deposited on PET substrates are measured before and after bending test. The experimental results obtained in this study provide strong evidences that the adhesive forces between CNTs and PET substrates can be substantially enhanced by corona-discharge pretreatment.

• Journal of Adhesion and Interface
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• v.19 no.4
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• pp.154-162
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• 2018

Plasma treatment and corona treatment have been used for surface modification of polydimethylsiloxane (PDMS) film by activating its surface with the -OH group. Adhesion promoter or coupling agent was also used to improve adhesion of PDMS film with various materials. However, obtained hydrophilicity onto the surface of PDMS films with those processes was transient and vulnerable. In this study, a new alkoxysilane-functionalized acrylic polymer precursor was first synthesized by copolymerization process, and then was reacted with HO-terminated PDMS through condensation reaction to prepare a new surface modifier for PDMS film. The structure and molecular weight of the prepared surface modifier were confirmed by 1H-NMR and GPC measurement. Surface properties of surface modifier-coated PDMS films were also investigated by using XPS, ATR and WCA analysis. The adhesion between the PDMS film and the surface modifier was tested using cross-cut test.

• Proceedings of the Korean Fiber Society Conference
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• 1991.06b
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• pp.47-47
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• 1991

• Korean Journal of Food Science and Technology
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• v.47 no.1
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• pp.70-74
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• 2015

Inactivation of microorganisms in grains used for saengshik, a formulated health food, was attempted by corona discharge plasma jet (CDPJ). The initial microbial counts of the grains were in the range of $1.7{\times}10^3-9.9{\times}10^5CFU/g$. The CDPJ-inactivation effect was increased with electric current in the range of 1-1.5 A. Regarding span length between the tips of the electrodes and the treatment surface, the highest inactivation effect was observed at 25 mm. The inactivation pattern fitted well to the Singh-Heldman model. Bacteria were more labile to the CDPJ inactivation than yeasts and molds. Among tested grains, white rice showed the highest sterility followed by pressed barley and brown rice. Despite the inactivation by plasma, the thiobarbituric acid content of the grains remained unchanged over 10 min of treatment. Our results indicated the potential of the CDPJ treatment to improve the hygiene of saengshik products with no remarkable changes in lipid quality.

• Journal of fish pathology
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• v.33 no.1
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• pp.63-69
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• 2020

Fish culture is constantly threatened by various infectious diseases which are largely transmitted by water. Plasma technology is being used to sterilize polluted water in many industries. In this study, two bacterial pathogens Aeromonas salmonicida and Streptococcus iniae, and a virus (viral hemorrhagic septicemia virus, VHSV) were subjected to plasma water that was produced by a corona discharge system. Growth of A. salmonicida was greatly inhibited from 10^5.61 CFU/ml in positive control to 10^3.51 CFU/ml in treated group by only 60 sec contact with plasma water. Similarly, S. iniae was inhibited from 10^5.85 CFU/ml to 10^3.40 CFU/ml. VHSV titer also decreased from 10^4.1 TCID₅₀/ml to 10^1.45 TCID₅₀/ml by the same treatment. Activation of water by the plasma was confirmed by the existence of ozone in the plasma water. These results suggest that plasma water could efficiently disinfect fish pathogens, possibly by the action of reactive oxygen species contained in the plasma water.

• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.2
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• pp.70-77
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• 2012

The selective catalytic reduction(SCR) system used to reduce NOx in diesel engines requires an NO/$NO_2$ ratio of about 1 in exhaust emissions to realize the fast SCR mode at temperatures lower than $300^{\circ}C$. This study investigated the characteristics of a plasma system as a pre-active apparatus for the fast SCR reaction mode of an SCR system. Plasma was generated by the pulse corona discharge(PCD) method with a four-channel wire-cylinder reactor. This study showed that plasma was easily generated in the exhaust gas by the PCD system, and the peak voltage of the normal state condition for plasma generation was generally 12 kV. The PCD system easily converted NO into $NO_2$ at lower temperatures and the NO/$NO_2$ conversion ratio increased with the discharge current for plasma generation. But the PCD system could not convert NO into $NO_2$ at higher engine speeds and higher engine loads due to the lack of oxygen in exhaust gas. The PCD system also activated the diesel oxidation catalysts(DOC) system to reduce CO emissions.

• Journal of Biomedical Engineering Research
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• v.10 no.1
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• pp.43-52
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• 1989

We modified polymer surfaces, polyethylene, polystyrene and polyester, to improve cellcompatibility. For surface modification of the polymers, we used various surface treatment methods; physicochemical oxidation methods such as plasma discharge, corona discharge, sulfuric acid and chloric acid treatments, and biological methods such as adsorption of plasma protein and fibronectin onto the polymer surfaces. The treated polymer surfaces were characterized by electron spectroscopy for chemical analysis ( ESCA ). The physicochemically treated polymers showed different surface chemical structures depending on the treated methods. The sulfuric acid-treated surfaces showed greater carboxyl groups than those of plasma- or corona- treated surfaces, while the chloric acid-treated one showed high density of hydroxyl group on the surface. By the biological treatments, the surfaces were uniformly coated with proteins. The fibronectin adsorbed on the surface seems to have unique properties for cell binding.