• Bulletin of the Korean Chemical Society
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• 제25권1호
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• pp.73-78
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• 2004

A highly sensitive detecting method has been developed for determining part per billion of sulfur in $H_2S$/Ar plasma. The method is based on the excitation of Ar/$H_2S\;or\;Ar/H_2S/O_2$ mixture in hollow cathode glow discharge sustained by radiofrequency (RF) or 60 Hz AC power and the spectroscopic measurement of the intensity of emission lines from electronically excited $S_2^*\;or\;SO_2^*$ species, respectively. The RF or AC power needed for the excitation did not exceed 30 W at a gas pressure maintained at several mbar. The emission intensity from the $SO_2^*$ species showed excellent linear response to the sulfur concentration ranging from 5 ppbv, which correspond to S/N = 5, to 500 ppbv. But the intensity from the $S_2^*$ species showed a linear response to the $H_2S$ only at low flow rate under 20 sccm (mL/min) of the sample gas. Separate experiments using $SO_2$ gas as the source of sulfur demonstrated that the presence of $O_2$ in the argon plasma is essential for obtaining prominent $SO_2^*$ emission lines.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 가을 학술발표회 논문집
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• pp.307-308
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• 2003

Improved wettability and dyeability of Polypropylene(PP) fabrics were obtained using glow discharge plasma by grafting nitrogen-containing active groups on the surface. Few studies of glow discharge plasma on PP fabrics exist. The objective of this study was to give a fabric a good affinity for water. (omitted)

• 대한전기학회:학술대회논문집
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• 대한전기학회 1985년도 하계학술회의논문집
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• pp.224-227
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• 1985

During operation of an RF glow discharge system, it can be observed that the reflected power tends to increase in small value, due to changes in the impedance of the system. This problem can be relieved by adding an automatic impedance matching circuit to the system. This paper presents a detailed method of automatically matching the input impedance of a 50 ohm transmission line to an RF glow discharge system at 13.56 MHZ.

• 전기학회논문지P
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• 제67권4호
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• pp.214-220
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• 2018

Light sources induced by gas discharge using rare gases have been widely used in the thin film deposition, the surface modification and the polymer etching. A dielectric barrier discharge (DBD) has been developed in order to consistently emit light and control the wavelength of the emission light. However, much research on the characteristics of the movement of discharge particles is required to improve the efficiency of the light lamp and the life-time of the light apparatus in detail. In this paper, we developed a He DBD discharge simulation tool and investigated the characteristics of discharge particles which were electrons, two positive ions ($He^+$, $He_2^+$) and 5 excited particles ($He^*(1S)$, $He^*(3S)$, $He^*$, $He^{**}$, $He^{***}$). The discharge currents showed the transition from pulse mode to continuous mode with the increase of power. With the accumulated charges on the barrier walls, the discharge current was rapidly increased and caused oscillation of the discharge voltage. As the gas pressure increased, $He_2^+$ and $He^*(3S)$ became the dominant activated particles. The input power was mostly consumed by electrons and $He_2^+$ ion. And the change curve showed that power consumption by electrons increased more with gas pressure than with source voltage or frequency.

• 한국진공학회지
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• 제12권1호
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• pp.51-54
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• 2003

아르곤 방전 기체의 음 글로우 영역에서 자발적 직동의 광검류 신호를 관찰하였다. 자발적 진동의 광검규 신호는 3 mA 보다 낮은 땅선 전류에서 나타난다. 준안정 준위의 인자 밀도 변화와 1s-2p 전이의 방출 세기를 동시에 측정한 결과, 자발적 진동 신호를 발생시키는 메커니즘 중의 한 가지는 느린 전자의 충돌에 의한 준안정 준위 원자의 단계적 이온화이다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.921-924
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• 2006

In an attempt to enhance secondary electron emission characteristics of PDP, $12CaO{\cdot}7Al_2O_3$ electride was used as electron emission layer of PDP discharge cells. The compound was synthesized by Ca-treatment and its electron emission behavior during the glow discharge was measured. The results indicated that the spayed electride reduces the discharge voltage by ${\sim}20$ volts and decrease the discharge delay by more than 70%.

• 전기학회논문지
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• 제63권1호
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• pp.80-84
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• 2014

The discharge characteristics of Surface Dielectric Barrier Discharge (SDBD) reactor are investigated to find optimal driving condition with adjusting various parameter. When the high voltage with sine wave form is applied to SDBD source, successive pulsed current waveforms are observed owing to multiple ignitions through the long discharge channel and wall charge accumulation on the dielectric surface. The discharge voltage, total charge between dielectrics, mean energy and power are calculated from measured current and voltage according to electrode gap and dielectric thickness. Discharge mode transition from filamentary to diffusive glow is observed for narrow gap and high applied voltage case. However, when the diffusive discharge is occurred with high applied voltage, the actual firing voltage is always lower than that with low driving voltage. The $Si_3N_4$, $MgF_2$, $Al_2O_3$ and $TiO_2$ are considered for dielectric protection and high secondary electron emission coefficient. SDBD with $MgF_2$ shows the lowest breakdown voltage. $MgF_2$ thin film is proposed as a protection layer for low voltage atmospheric dielectric barrier discharge devices.

• Journal of Korean Vacuum Science & Technology
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• 제6권1호
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• pp.16-21
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• 2002

Ti-0 film is a kind of biocompatible surface materials. In this paper, a new method, glow discharge plasma oxidizing, has been used in synthesizing Ti-O gradient films on Ti6A14V substrates. The effects of ion bombardment and process parameters on the structures of titanium oxide layers have been investigated. The results demonstrate that DC glow plasma oxidizing is more efficient in preparation of dense, hard, and high adhesive Ti-O biomedical films on titanium and its alloys. Samples treated by this method show higher hardness values than by others. Especially, in the condition of hollow cathode discharge, the ion bombardment enhances ionization of oxygen, promotes the oxygen permeation and facilitates the formation of the oxide of low valence states of titanium.

• Korean Chemical Engineering Research
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• 제49권6호
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• pp.704-709
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• 2011

접촉글로우방전 전기분해(CGDE)에 의한 후코이단의 저분자화에 대해 연구하였다. CGDE 공정 후에 후코이단을 기능성 식품재료로 사용하기 위해 유기산을 전해질로 사용하였다. 실험결과 유기산을 이용한 전기분해에 의해 후코이단의 분자량을 효과적으로 감소시킴을 보였다. 전해질의 농도가 증가하면 글로우방전 시작 전압이 감소하고 글로우방전시작 전류는 증가하였다. 반응시간에 따른 후코이단의 분자량 변화로부터 저분자화반응은 1차 반응속도 식을 따름을 보였다. 유기산을 이용한 CGDE에 의해 후코이단의 분자량이 처음의 약 1/77로 감소하였으며, CGDE 저분자화 과정에서 유리된 황산기 함량이 작았다.

• Korean Chemical Engineering Research
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• 제46권5호
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• pp.886-891
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• 2008

접촉 글로우방전 전기분해(CGDE)는 일반적인 전기분해와 다르게 높은 전압에서 전극과 전극을 둘러싼 전해질 사이에 글로우 방전에 의한 플라즈마가 형성돼 일어나는 전기분해다. 본 연구에서는 먼저 NaCl 용액에서 CGDE 거동을 파악하고 그리고 CGDE에 의한 후코이단의 저분자화에 대해 연구하였다. NaCl 전해질에서 CGDE 과정이 시작되면 전압 증가에 따라 글로우 방전이 활발하게 되고 그에 따라 전류밀도가 감소하고 온도가 내려갔다. 반응시간에 따른 후 코이단의 분자량 변화로부터 저분자화반응은 1차 반응속도 식을 따름을 보였다. CGDE에 의해 후코이단의 분자량이 처음의 약 1/40로 감소하였으며, CGDE 저분자화 과정에서 황산기 함량과 fucos 함량의 감소가 없었다.