• Food Science of Animal Resources
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• v.33 no.3
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• pp.317-324
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• 2013

Radio-frequency driven atmospheric pressure plasma using argon gas was studied in the inactivation of Campylobacter jejuni in order to investigate its applicability. First, the inactivation study was conducted on an agar surface. C. jejuni NCTC11168 was reduced by more than 7 Log CFU after an 88 s treatment. Another strain, ATCC49943, was studied; however, the inactivation was less efficient, with a 5 Log CFU reduction after a 2 min treatment. Then, chicken breast ham was studied at the $10^6$ CFU inoculation level. The inactivation efficiency was much lower for both strains compared to that on the agar plates. C. jejuni NCTC11168 and ATCC49943 were reduced by 3 Log CFU after a 6 min treatment and by 1.5 Log CFU after a 10 min treatment, respectively. The scanning electron microscopy analysis indicated that C. jejuni cells were deformed or transformed into coccoid form under the plasma treatment. During the plasma treatment, the temperature of the samples did not rise above $43^{\circ}C$, suggesting that heat did not contribute to the inactivation. Meanwhile, water activity significantly decreased after a 10 min treatment (p<0.05). This study conveyed that radio-frequency atmospheric pressure plasma can effectively inactivate C. jejuni with strain-specific variation.

• Journal of the Semiconductor & Display Technology
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• v.16 no.4
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• pp.59-62
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• 2017

In this paper, atmospheric pressure plasma treatment was proposed for high performance indium gallium zinc oxide thin film transistor (IGZO TFT). RF Ar plasma treatment is performed at room temperature under atmospheric pressure as a simple and cost effective channel surface treatment method. The experimental results show that field effect mobility can be enhanced by $2.51cm^2/V{\cdot}s$ from $1.69cm^2/V{\cdot}s$ to $4.20cm^2/V{\cdot}s$ compared with a conventional device without plasma treatment. From X-ray photoelectron spectroscopy (XPS) analysis, the increase of oxygen vacancies and decrease of metal-oxide bonding are observed, which suggests that the suggested atmospheric Ar plasma treatment is a cost-effective useful process method to control the IGZO TFT performance.

• Korean Journal of Biological Psychiatry
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• v.3 no.2
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• pp.262-268
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• 1996

It has been known that clozapine is more selective mesolimbic dopamin $D_2$ receptor antagonist and related to 5-HT receptor. In this study, we wxamined the plasma homovanillic acid(HVA), serotonin(5-HT), and 5-hydroxyindoleacetic acid(5-HIM) levels in refractory schizophrenics during clozapine treatment. And we assessed the effects of clozapine on these plasma monoamine metabolites and their association with psychopathology and treatment response. Eight refractory schizophrenic patients(DSM-IV) have entered the study for 3 months during clozapine treatment. Patients were admitted to the inpatient sevice and withdrawn from all neuroleptics for 7-14 days but exceptionally occasional doses of lorazepam was given if needed for behavioral control. The dose of clozapine was titrated as tolerated to 800mg/day. The plasma HVA. 5-HIM and 5-HT levels were measured before treatment and following 2nd week, 4th week, 8th week, and 12th during treatment. Psychopathology was assessed with Brief Psychiatric Rating Scale (BPRS) and Positive and Negative Synrome Scale(PANSS) before and during clozapine treatment. During clozapine treatment, no statistically significant changes were found in plasma HVA, 5-HIM, 5-HT levels, and HVA/5-HIM ratio between baseline and following 2nd week, 4th week, 8th week, 12th week. However, the change in plasma 5-HIAA/5-HT ratio from baseline to 4th week was statistically significant. Generally, changes of plasma HVA, 5-HIAA, 5-HT levels and HVA/5-HIAA ratio were not associated with psychopathology but 5-HIAA was associated with in positive symptoms and general psychopathology of PANSS. These results suggest that clozapine has been found to have relatively weak dopaminergic blokade and stronger serotonergic antagonism.

• Journal of Conservation Science
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• v.30 no.3
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• pp.299-306
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• 2014

The possibility of a low-temperature argon plasma treatment as a mean of restoration technology for contaminated invaluable archive materials and artefacts, and evidencing documents was investigated along with an oxygen plasma treatment for comparison. For this purpose, the degree of color changes, ${\Delta}E^*ab$, and surface morphological changes due to plasma treatments as an evaluation of removal performance of artificial contaminants such as brilliant green dye and carbon deposit on cellulose acetate and plain paper as matrices, respectively, were measured and analyzed using a spectrophotometer and a field emission scanning electron microscope. Compared to the argon plasma treatment with sputtering characteristic, that of the oxygen plasma with characteristic of an oxidation reaction has shown superior results in removing the contaminants; the oxygen plasma has proven to damage the matrices significantly due to its oxidative characteristic, and post-plasma reactions has anticipated to be also detrimental to the surfaces, whereas, the problems caused by the counterpart has resulted in being negligible and rather has thought to be an appropriate mean for delicate restoration and/or removal operations of contaminants.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.1
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• pp.30-33
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• 2006

Transparent indium tin oxide (ITO) anode surface was modified using $O_3$ Plasma and organic ultrathin buffer layers were deposited on the ITO surface using 13.56 MHz RF plasma polymerization technique. The EL efficiency, operating voltage and lifetime of the organic light-emitting device (OLED) were investigated in order to study the effect of the plasma surface treatment and role of plasma polymerized organic ultrathin buffer layer. Poly methylmethacrylate (PMMA) layers were plasma polymerized on the ITO anode as buffer layer between anode and hole transport layer (HTL). The plasma polymerization of the organic ultrathin layer were carried out at a homemade capacitive-coupled RF plasma equipment. N,N'-diphenyl-N,N'(3- methylphenyl)-1,1'-diphenyl-4,4'-diamine (TPD) as HTL, Tris(8-hydroxyquinolinato) Aluminum $(Alq_3)$ as both emitting layer (EML)/electron transport layer (ETL), and aluminum layer as cathode were deposited using thermal evaporation technique. Effects of the plasma surface treatment of ITO and plasma polymerized buffer layers on the OLED performance were discussed.

• Biomolecules & Therapeutics
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• v.22 no.6
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• pp.477-490
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• 2014

Non-thermal atmospheric-pressure plasma, also named cold plasma, is defined as a partly ionized gas. Therefore, it cannot be equated with plasma from blood; it is not biological in nature. Non-thermal atmospheric-pressure plasma is a new innovative approach in medicine not only for the treatment of wounds, but with a wide-range of other applications, as e.g. topical treatment of other skin diseases with microbial involvement or treatment of cancer diseases. This review emphasizes plasma effects on wound healing. Non-thermal atmospheric-pressure plasma can support wound healing by its antiseptic effects, by stimulation of proliferation and migration of wound relating skin cells, by activation or inhibition of integrin receptors on the cell surface or by its pro-angiogenic effect. We summarize the effects of plasma on eukaryotic cells, especially on keratinocytes in terms of viability, proliferation, DNA, adhesion molecules and angiogenesis together with the role of reactive oxygen species and other components of plasma. The outcome of first clinical trials regarding wound healing is pointed out.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.44 no.1
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• pp.31-36
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• 2012

In the previous study, the possibility of modifying the surface properties of base paper with plasma treatment was evaluated. It was shown that only the hydrophilic properties of the base paper surface was increased while there was no changes in physical and optical properties. Only the surface of the plasma treated side was modified. In this study, the effect of plasma treatment on binder migration was elucidated. The base paper was plasma treated with various voltage and then the plasma treated base papers were coated with varying coated weight. The surface strength of the coated paper (dry and wet pick) was increased with plasma treatment, which implies that the plasma treatment of base paper can inhibit the binder migration.

• Macromolecular Research
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• v.12 no.1
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• pp.134-140
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• 2004

Semi-crystalline poly(ethylene terephthalate) (PET) film surfaces were modified with argon and oxygen plasmas by radio-frequency (RF) glow discharge at 240 mTorr/40 W; the changes in topography and surface structure were investigated by atomic force microscopy (AFM) in conjunction with specular reflectance of infrared microspectroscopy (IMS). Under our operating conditions, analysis of the AFM images revealed that longer plasma treatment results in significant ablation on the film surface with increasing roughness, regardless of the kind of plasma used. The basic topographies, however, were different depending upon the kind of gas used. The specular reflectance analysis showed that the ablative mechanisms of the argon and oxygen plasma treatments are entirely different with one another. For the Ar-plasma-treated PET surface, no observable difference in the chemical structure was observed before and after plasma treatment. On the other hand, the oxygen-plasma-treated PET surface displays a significant decrease in the number of aliphatic C-H groups. We conclude that a constant removal of material from the PET surface occurs when using the Ar-plasma, whereas preferential etching of aliphatic C-H groups, with respect to, e.g. , carbonyl and ether groups, occurs upon oxygen plasma.

• Applied Science and Convergence Technology
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• v.25 no.3
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• pp.51-55
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• 2016

The surface treatment of a titanium implant is investigated with a non-thermal atmospheric pressure plasma jet. The plasma jet is generated by the injection of He and $O_2$ gas mixture with a sinusoidal driving voltage of 3 kV or more and with a driving frequency of 20 kHz. The generated plasma plume has a length up to 35 mm from the jet outlet. The wettability of 4 different titanium surfaces with plasma treatments was measured by the contact angle analysis. The water contact angles were significantly reduced especially for $O_2/He$ mixture plasma, which was explained with the optical emission spectroscopy. Consequently, plasma treatment enhances wettability of the titanium surface significantly within the operation time of tens of seconds, which is practically helpful for tooth implantation.

• Fashion & Textile Research Journal
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• v.15 no.3
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• pp.461-466
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• 2013

Synthetic fiber materials were developed due the desire of consumers for high-quality, high-performance and comfort. A high functionality of synthetic fiber can be obtained through surface treatment that can improve hydrophilic properties, color depth after dyeing and adhesion properties. These advantages create added-value. Hydrophobic properties are an important feature to create added-value (such as hydrophilic properties). One side processing is a method of imparting to contrary function on the front and rear side. In this study, fluorine-coated Nylon/PU blended fabric was treated on only one side with a low-temperature plasma treatment; subsequently, the contact angles decreased by increasing the time and intensity of the plasma treatment. The contact angle of the untreated surface and the treated surface was different. It a showed a difference in the properties of both surfaces. Tensile strength and stiffness decreased by increasing the time and intensity of the plasma treatment. However, plasma treatment did not significantly change the tensile strength and stiffness on both surfaces of the fabric. SEM photographs showed the surface of fluorine-coated fabric and the etching surface by using plasma treatment on the fabric. Plasma treatment was confirmed not to affect the physical properties of the fabric.