• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.421-421
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• 2012

Graphene has drawn enormous attention owing to its outstanding properties, such as high charge mobility, excellent transparence and mechanical property. Synthesis of Graphene by chemical vapor deposition (CVD) is an attractive way to produce large-scale Graphene on various substrates. However the fatal limitation of CVD process is high temperature requirement(around $1,000^{\circ}C$), at which many substrates such as Al substrate cannot endure. Therefore, we propose plasma enhanced CVD (PECVD) and decrease the temperature to $400^{\circ}C$. Fig. 1 shows the typical structure of RF-PECVD instrument. The quality of Graphene is affected by several variables. Such as plasma power, distance between substrate and electronic coil, flow rate of source gas and growth time. In this study, we investigate the influence of these factors on Graphene synthesis in vacuum condition. And the results were checked by Raman spectra and conductivity measurement.

• 대한전기학회논문지
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• 제39권11호
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• pp.1227-1234
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• 1990

This study is to figure out the properties of the DC thermal plasma at low pressure. For this purpose, a temperature measurement system utilizing emission spectroscopy has been set up and its measurement method and results have been described. At low pressure, the plasma has shown drastic changes in its appearance. The discharge characteristics under low pressure have been measured and analyzed. The temperature of thermal plasma generated in this research has been ranged from 10, 000 K to 15, 000 K. Temperature has been observed to increase with the flow rate and magnetic field strength. The temperature characteristics at low pressure has been observed to coincide with the reported results.

• 한국임상약학회지
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• 제10권1호
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• pp.38-41
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• 2000

A high-performance liquid chromatographic method with fluorometric detection was evaluated for analysis of ofloxacin in plasma. Biological fluids (plasma, $200\;{\mu}L$) were prepared for assay by protein precipitation with chlorofurm. The detection of ofloxacin and triamterene as an internal standard were performed at 358 nm for excitation and 495 nm for emission. The HPLC separation was carried out on Ultrasphere ODS column (4.6 mm${\times}25\;cm,\;5\;{\mu} m$) with acetonitrile $(45\%)$-phosphoric acid $(1.5\%)\;containing\;0.3\%$ sodium laurylsulfate as the mobile phase. The flow-rate was 1.0 mL/min. The calibration graphs were linear from 3.0 to 80 ng/mL with r=0.998. The minimal detectable concentration in plasma was 1.5 ng/mL. The proposed technique is reproducible, selective, reliable and sensitive.

• 한국표면공학회지
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• 제29권5호
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• pp.593-598
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• 1996

Previously, in trying to prepare perovskite type oxide powders by microwave heating, we found out a non-equilibrium argon plasma is generated around the powders and discharge continues stable at atmospheric pressure. In this study, we tried the plasma decomposition of heat-stable higher organic compound such as palmitic acid which is the principal constituent of the fimger fats. It was proved that suitable amount of coexistence of oxygen radicals into the argon flow accelerates the decomposition of palmitic acid. The argon-oxygen mixed gas plasma was able to perform a complete elimination of higher organic compound.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 방전 플라즈마 유기절연재료 초전도 자성체연구회
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• pp.104-108
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• 2004

The effect of magnetic field was measured on NOx removal for cylinder-wire plasma reactor with magnetic field applied to electric field vertically. Power was supplied to plasma reactor using rotating spark gap switch. Consumption power increased with increasing discharge voltage. When magnetic field was applied to electric field vertically, consumption power was less than that without magnetic field because of lorenz's force. NOx removal rate of plasma reactor with magnetic field were higher, 10-15%, than that of plsama reactor without magnetic field. And NOx removal rate decreased with increasing gas flow rate.

• 한국가시화정보학회지
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• 제17권1호
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• pp.53-59
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• 2019

Particle image velocimetry is performed in order to analyze flowfield induced by a dielectric barrier discharge plasma actuator. The velocity vector fields are obtained for the two different input voltage conditions; the voltage 3 and 5 kV at the frequency 10 kHz. The obtained flowfields show that the air is accelerated and its speed increase almost linearly over the covered electrode. The amount of momentum induced by the DBD plasma actuator is estimated from the obtained velocity fields, and the estimated values reasonably agree with the previous experiment.

• 약학회지
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• 제39권5호
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• pp.480-486
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• 1995

The change in discharge current of a glow discharge has been shown the potential sensitive detector for gas chromatography. To investigate the effect of carrier gas on the electrical characteristics of the discharge and the peak response, the discharge pressure, gas flow rate, and discharge gap have been studied. The discharge gas included the Ar, He, and N$_{2}$. The gas flow rate has been found one of the important parameters to affect both the electrical characteristics and the peak response.

• Journal of Chest Surgery
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• 제49권3호
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• pp.145-150
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• 2016

Background: Extracorporeal circulation (ECC) can induce alterations in blood viscoelasticity and cause red blood cell (RBC) aggregation. In this study, the authors evaluated the effects of pump flow pulsatility on blood viscoelasticity and RBC aggregation. Methods: Mongrel dogs were randomly assigned to two groups: a nonpulsatile pump group (n=6) or a pulsatile pump group (n=6). After ECC was started at a pump flow rate of 80 mL/kg/min, cardiac fibrillation was induced. Blood sampling was performed before and at 1, 2, and 3 hours after ECC commencement. To eliminate bias induced by hematocrit and plasma, all blood samples were adjusted to a hematocrit of 45% using baseline plasma. Blood viscoelasticity, plasma viscosity, hematocrit, arterial blood gas analysis, central venous $O_2$ saturation, and lactate were measured. Results: The blood viscosity and aggregation index decreased abruptly 1 hour after ECC and then remained low during ECC in both groups, but blood elasticity did not change during ECC. Blood viscosity, blood elasticity, plasma viscosity, and the aggregation index were not significantly different in the groups at any time. Hematocrit decreased abruptly 1 hour after ECC in both groups due to dilution by the priming solution used. Conclusion: After ECC, blood viscoelasticity and RBC aggregation were not different in the pulsatile and nonpulsatile groups in the adult dog model. Furthermore, pulsatile flow did not have a more harmful effect on blood viscoelasticity or RBC aggregation than nonpulsatile flow.

• 산업기술연구
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• 제21권B호
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• pp.149-153
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• 2001

A study on the particle growth in $TEOS/O_2$ plasma was performed, and particle size and its distribution was measured by the electrical aerosol analyzer (EAA), light scattering particle size analyzer and the particle size was also determined by SEM. The effects of process variables such as total gas flow rate, reactor pressure, supplied power and initial reactant concentration on the particle growth were investigated. From the EAA results, the particle size distribution is divided into three groups of the cluster size and the small and large size particles. The particle size distribution measured by the light scattering particle size analyzer becomes bimodal, because the cluster size particles smaller than 20 nm in diameter cannot be detected by the light scattering particle size analyzer. The size of particles measured by the light scattering particle size analyzer is in good agreements with those by the SEM. Also we could understand that the particle formation is very sensitive to the changes of reactor pressure and reactant concentration. As the total gas flow rate increases, the particle size decreases because of the shorter residence time. As the reactor pressure, or the reactant concentration increases, the particle concentration increases and the particles grow more quickly by the faster coagulation between particles.

• 한국환경과학회지
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• 제23권9호
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• pp.1601-1608
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• 2014

Plasma reactor was used for the inactivation of Phytophthora capsici which is phytophthora blight pathogen in aquiculture. Effects of first voltage, second voltage, air flow rate, pH, incubation water concentration were examined. At the low $1^{st}$ voltage, under 80 V, the lag phase was noticed within 30 sec, however, it was not shown over 100 V. The variation of optimum operation condition was not shown by the variation of microorganisms. However, the inactivation rate was different by the variation of species of microorganisms. The inactivation rate and efficiency were increased by the increase of $2^{nd}$ voltage. The highest initial inactivation rate was shown at pH 3 and the rate was decreased by the increase of pH. The inactivation rate increased by the increase of air flow rate, however, it was shown as similar at the rate of 4 L/min and 5 L/min. The inactivation rate was distinctly decreased at the three times concentration of incubation solution comparing at the distilled water and basic incubation solution.