• Textile Coloration and Finishing
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• v.20 no.4
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• pp.53-59
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• 2008

For the modification of wool surface, wool fabrics treated with oxygen low-temperature plasma(LTP) and dichloroisocyanuric acid(DCCA) were dyed with milling type acid dye. The difference of dyeing properties on modified and control wool fabric were investigated. DCCA treated wool showed that saturation dye uptake and dyeing desorption ratio were higher than LTP treated wool. Dyeing transition temperatures of DCCA and LTP treated wool fabrics were 20$^{\circ}C$ degree lower than control wool fabric. In light color fastness test, DCCA treated wool fabric was 1 grade lower than LTP or control wool fabric.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.4
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• pp.632-637
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• 2003

In this study, the effect of surface treatment of CFRP and aluminum on the fracture toughness of CFRP/aluminum composites was investigated. CFRP was surface-treated by Ar$^{+}$ ion beam under oxygen environment, and the aluminum was surface-treated by DC plasma. CFRP was adhesively bonded to aluminum using the secondary bonding procedure. Cracked lap shear specimens were used to determine fracture toughness. Three cases of cracked lap shear specimens were made depending on the surface treatment. The values of fracture toughness of three cases were compared to each other It was found that the fracture toughness of ion beam-treated CFRP/aluminum composites was almost 72 % higher than that of unrented CFRP/aluminum composites. The fracture toughness of CFRP/plasma-treated aluminum composites was 50 % higher than that of untreated CFRP/aluminum composites.s.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.1878-1880
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• 2005

In this research, We investigated the effect of $O_2/O_3$ Plasma treatment of indium-tin oxide (ITO) surface on the performance of organic light emitting devices (OLEDs). The OLED had a structure of ITO/N,N'-diphenyl-N,N' -(3-methylphenyl)-1, 1'-biphenyl-4-4'-diamine (TPD)/Tris (8-hydroxyquinolinato) Aluminum $(Alq_3)/Al$. The ITO surface was treated by $O_2/O_3$ plasma with different RF power chamber pressure and exposure time. As a result, the emission efficiency of the OLEDs could be improved obviously.

• Journal of Environmental Science International
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• v.27 no.8
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• pp.621-629
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• 2018

Many chemically active species such as ${\cdot}H$, ${\cdot}OH$, $O_3$, $H_2O_2$, hydrated $e^-$, as well as ultraviolet rays, are produced by Dielectric Barrier Discharge (DBD) plasma in water and are widely use to remove non-biodegradable materials and deactivate microorganisms. As the plasma gas containing chemically active species that is generated from the plasma reaction has a short lifetime and low solubility in water, increasing the dissolution rate of this gas is an important challenge. To this end, the plasma gas and water within reactor were mixed using the air-automizing nozzle, and then, water-gas mixture was injected into water. The dissolving effect of plasma gas was indirectly confirmed by measuring the RNO (N-Dimethyl-4-nitrosoaniline, indicator of the formation of OH radical) solution. The plasma system consisted of an oxygen generator, a high-voltage power supply, a plasma generator and a liquid-gas mixing reactor. Experiments were conducted to examine the effects of location of air-automizing nozzle, flow rate of plasma gas, water circulation rate, and high-voltage on RNO degradation. The experimental results showed that the RNO removal efficiency of the air-automizing nozzle is 29.8% higher than the conventional diffuser. The nozzle position from water surface was not considered to be a major factor in the design and operation of the plasma reactor. The plasma gas flow rate and water circulation rate with the highest RNO removal rate were 3.5 L/min and 1.5 L/min, respectively. The ratio of the plasma gas flow rate to the water circulation rate for obtaining an RNO removal rate of over 95% was 1.67 ~ 4.00.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.160-160
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• 2010

Organic electronic devices require a passivation layer to ensure sufficient lifetime. Specifically, flexible organic electronic devices need a barrier layer that transmits less than $10^{-6}\;g/m^2/day$ of water and $10^{-5}\;g/m^2/day$ of oxygen. To increase the lifetime of organic electronic device, therefore, it is indispensable to protect the organic materials from water and oxygen. Severe groups have reported on multi-layerd barriers consisting inorganic thin films deposited by plasma enhenced chemical deposition (PECVD) or sputtering. However, it is difficult to control the formation of granular-type morphology and microscopic pinholes in PECVD and sputtering. On the contrary, atomic layer deoposition (ALD) is free of pinhole, highly uniform, conformal films and show good step coverage. In this study, the passivation layer was deposited using single-process PEALD. The passivation layer, in our case, was a bilayer system consisting of $Al_2O_3$ films and a $TiO_2$ buffer layer on a poly (ether sulfon) (PES) substrate. Because the deposition temperature and plasma power have a significant effect on the properties of the passivation layer, the characteristics of the $Al_2O_3$ films were investigated in terms of density under different deposition temperatures and plasma powers. The effect of the $TiO_2$ buffer layer also was also addressed. In addition, the water vapor transmission rate (WVTR) and organic light-emitting diode (OLEDs) lifetime were measured after forming a bilayer composed of $Al_2O_3/TiO_2$ on a PES substrate.

• Journal of Nutrition and Health
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• v.35 no.1
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• pp.30-36
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• 2002

This study was conducted to evaluate the effect of regular exercise and other relating factors on the activities of erythrocyte antioxidant enzymes and plasma total radical-trapping antioxidant potential (TRAP) in 61 healthy male college students. The study population were divided in two groups ; small amount of exerciser (exorcise time less than 30min/d) and moderate amount of exerciser (exorcise time more than 30min/d) according to their physical exercise habits measured by a questionnaire. Dietary intake of vitamin C and vitamin E, Plasma lipid Profiles, erythrocyte superoxide dismutase(SOD), glutathione peroxidase(GSH-Px) and catalase activities, as well as plasma TRAP levels were determined. Plasma TRAP level was significantly higher in moderate amount of exercisers than that in small amount of exercisers. No significant differences were observed in erythrocryte SOD, catalase and GSH-Px between the two groups. Mean exercise time was positively correlated with the plasma level of TRAP significantly, and amount of alcohol consumption was negatively correlated with the erythrocyte SOD activity, Dietary vitamin C and I intakes did not correlated with either erythrocyte enzyme activities or plasma TRAP levels. There were positive correlations between plasma HDL-cholesterol, and erythrocyte GSH-Px or plasma TRAP levels. Plasma vitamin C concentrations was negatively correlated with plasma TRAP levels and erythrocyte SOD activity, however plasma vitamin C concentration was positively correlated with erythrocyte GSH-Px activity, The results would suggest that regular moderate exercise, nonsmoking, high HDL-cholesterol and high plasma vitamin E concentration enhance antioxidant defences against reactive oxygen species and may increase the likelihood of a healthier life span.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.97-97
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• 2000

In this thesis, the metastable state diamond thin films have been deposited on Si substrates from methane-hydrogen and oxygen mixture using Microwave Plasma Enhanced Chemical Vapor deposition (MWPCVD) method. Effects of each experimental parameters of MWPCVD including methane concentrations, oxygen additions, operating pressure, deposition time, etc. on the growth rate and crystallinity were investigated. SEM, XRD, and Raman spectroscopy were employed to analyze the growth rate and morphology, crystallinity and prefered growth direction, and relative amounts of diamond and non-diamond phases respectively. As a methane concentration below 4%, the deposited films having well-defined facets could be obtained. As the methane concentration increases over 4%, the shape of films gradually changed into a amorphos form. The best crystallinity of the film at 3% in the Raman spectroscopy. Addition of oxygen to the methane-hydrogen mixture gave an improved film crystallinity at 50% oxygen concentration due to its more effectiveness in the selective removal of the non-diamond phased compared to the of H atom. on the contrary, the growth rate generally decreased by oxygen to from the more stable CO and CO2 is responsible for such an effect. Upon increasing the operating pressure and time, increased of growth rate and crystallinity were increased simultaneously.

• Food Engineering Progress
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• v.14 no.3
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• pp.202-207
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• 2010

Low-pressure plasmas (LPPs) were generated with different gases such as air, oxygen and nitrogen, and their inactivation effects against Escherichia coli were compared in order to evaluate the potential as a non-thermal microbial disinfection technology. Homogeneous plasmas were generated under low pressure below 1 Torr at gas flow rate of 350 mL/min regardless the types of gases. Temperature increases by LPPs were not detrimental showing less than ${10^{\circ}C}$ and ${25^{\circ}C}$ increases after 5 and 10 min treatments, respectively. The smallest temperature increase was observed with air LPP, and followed by oxygen and nitrogen LPPs. More than 5 log reduction in E. coli was achieved by 5 min LPP treatment but the destruction effect was retarded afterward. The LPP inactivation was represented by a iphasic first order reaction kinetics. The highest inactivation rate constant was achieved in air LPP and followed by oxygen and nitrogen LPPs. The small D-values of the LPP also supported its potentialities as a non-thermal food surface disinfection technology in addition to the substantial microbial reduction of more than 5 logs.

• JSTS:Journal of Semiconductor Technology and Science
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• v.1 no.2
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• pp.95-102
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• 2001

Hafnium oxide thin films for gate dielectric were deposited at $300^{\circ}C$ on p-type Si (100) substrates by plasma enhanced chemical vapor deposition (PECVD) and annealed in $O_2$ and $N_2$ ambient at various temperatures. The effect of hydrogen treatment in 4% $H_2$ at $350^{\circ}C$ for 30 min on the electrical properties of $HfO_2$for gate dielectric was investigated. The flat-band voltage shifts of $HfO_2$capacitors annealed in $O_2$ambient are larger than those in $N_2$ambient because samples annealed in high oxygen partial pressure produces the effective negative charges in films. The oxygen loss in $HfO_2$films was expected in forming gas annealed samples and decreased the excessive oxygen contents in films as-deposited and annealed in $O_2$ or $N_2$ambient. The CET of films after hydrogen forming gas anneal almost did not vary compared with that before hydrogen gas anneal. Hysteresis of $HfO_2$films abruptly decreased by hydrogen forming gas anneal because hysteresis in C-V characteristics depends on the bulk effect rather than $HfO_2$/Si interface. The lower trap densities of films annealed in $O_2$ambient than those in $N_2$were due to the composition of interfacial layer becoming closer to $SiO_2$with increasing oxygen partial pressure. Hydrogen forming gas anneal at $350^{\circ}C$ for samples annealed at various temperatures in $O_2$and $N_2$ambient plays critical role in decreasing interface trap densities at the Si/$SiO_2$ interface. However, effect of forming gas anneal was almost disappeared for samples annealed at high temperature (about $800^{\circ}C$) in $O_2$ or $N_2$ambient.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.5
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• pp.442-449
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• 2006

Electrical, optical, and structural properties of indium zinc oxide (IZO) films grown by a box cathode sputtering (BCS) were investigated as a function of oxygen flow ratio. A sheet resistance of $42.6{\Omega}/{\Box}$, average transmittance above 88% in visible range, and root mean spare roughness of $2.7{\AA}$ were obtained even in the IZO layers grown at room temperature. In addition, it is shown that electrical characteristics of the top-emitting organic light emitting diodes (TOLEDs) with the BCS grown-IZO top cathode layer is better than that of TOLEDs with DC sputter grown IZO top cathode, due to absence of plasma damage effect. Furthermore the effects of oxygen flow ratio in IZO films are investigated, based on x-ray photoelectron spectroscopy (XPS), ultra violet/visible (UV/VIS) spectro-meter, scanning electron microscopy (SEM), and atomic force microscopy (AFM) analysis results.