• 한국환경과학회:학술대회논문집
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• 한국환경과학회 1996년도 가을 학술발표회 초록집
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• pp.74-75
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• 1996

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.259.1-259.1
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• 2014

Recently non-thermal plasma has been frequently applied to various research fields. The liquid plasma have received much attention lately because of interests in surgical and nanomaterial synthesis applications. Especially, intensive researches have been carried out for non-thermal plasma in liquid by using various electrode configurations and power supplies. We have developed a bioplasma source which could be used in a liquid, in which outer insulator has been covered onto the outer electrode. Also we have also put an insulator between the inner and outer electrode. Based on the surface discharge mode, the nonthermal bioplasma has been generated inside a liquid by using an alternating current voltage generator with peak voltage of 12 kV under driving frequency of 22 KHz. Here the discharge voltage and current have been measured for electrical characteristics. Especially, We have measured discharge and optical characteristics under various liquids of deionized (DI) water, tap water, and saline by using monochromator. We have also observed nitric oxide (NO), hydrogen peroxide (H2O2), and hydroxyl (OH) radical species by optical emission spectroscopy during the operation of bioplasma discharge inside various kinds of DI water, tap water, and saline. Here the temperature has been kept to be $40^{\circ}C$ or less when discharge in liquid has been operated in this experiment. Also we have measured plasma temperature by high speed camera image and density by using either H-alpha or H-beta Stark broadening method.

• 대한환경공학회지
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• 제22권12호
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• pp.2247-2254
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• 2000

본 연구는 저온 플라즈마 탈질 기술의 전력소모량 절감과 처리율 향상을 모색하고자 저온 플라즈마 조건에서 NOx와 반응제의 반응 특성을 고찰하였다. 실험은 $20Nm^3/hr$의 실제 배가스와 wire-plate type 플라즈마 반응기를 이용하여 진행되었으며, 반응제로는 파라핀계와 올레핀계 탄화수소 및 $NH_3$를 사용하였다. 저온 플라즈마 조건에서 올레핀계 탄화수소는 파라핀계 탄화수소에 비하여 NO의 산화에 탁월한 효과를 보여 다량의 $NO_2$를 생성할 뿐만 아니라 미량의 CO도 생성하였다. 또한 NOx의 초기농도가 높아지면 NO의 산화율은 감소할 뿐만 아니라 올레핀계 탄화수소의 소모량도 두드러진 증가를 보였다. 한편 $NH_3$은 저온 플라즈마 조건에서 NO와의 환원반응이 촉진되지 않았지만 올레핀계 탄화수소에 의하여 산화된 $NO_2$의 제거에는 효과적인 경향을 보였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.199-199
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• 2013

The distinctive cellular and mitochondrial dysfunctions of a human epithelial lung cancer cell line (H460) from a human lung fibroblastic normal cell line (MRC5) have been studied by dielectric barrier discharge (DBD) plasma treatment. The DBD plasma device have generated large amount of H2O2 and NOx in culture media which is dependent on plasma exposure time. It is found that the cell number of lung cancer cell H460 has been reduced more than the lung normal cell MRC5 as being increased exposure and incubation time. Also these both cell lines have showed mitochondria fragmentation under 5 minutes' plasma exposure, which is a clue of apoptosis. It is noted in this study that AnnexinV staining has showed not only early apoptosis, but also late apoptosis in lung cancer cell H460. Mitochondria enzyme activity and ATP generation have been also much reduced in lung cancer cell H460. Their mitochondrial membrane potential (${\Delta}{\psi}m$) has been found to be reduced in magnitude and shifted to the induced-potential level of cccp, while MRC5 mitochondrial membrane potential has been shifted slightly to that. These distinctively selective responses of lung cancer cell H460 from lung normal cell MRC5 gives us possibility of applying plasma to cancer therapy.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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• pp.917-921
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• 2002

In this paper, we made different types of non-thermal plasma reactors such as Metal-particle reactor with $Al_2O_3$ to measure NOx removal characteristic and the dielectric effect for NOx removal. NOx removal rate is not so good when we use just dielectric of $Al_2O_3$ at the Metal-particle reactor, also we just put sludge pellets(100%) without Metal-particle reactor with $Al_2O_3$ and dielectric such as $TiO_2$, $BaTiO_3$ to measure the effect of sludge for NOx removal so that NOx removal rate is almost the same. However NOx removal rate is more than 90% in case of the reactor of composition shape used both dielectric of $Al_2O_3$ and sludge pellets at the same time. In case of the shape of plasma reactor with dielectric, the Metal-particle reactor with $Al_2O_3$, and the metal-particle reactor with both $Al_2O_3$ and dielectric such as $TiO_2$, $BaTiO_3$ at the same time, they are almost the same effect for NOx removal, so we made MNPR(Metal-particle Non-thermal Plasma Reactor with $Al_2O_3$) to reduce these kinds of demerits. Finally, we think MNPR should be much better than other reactors for NOx removal.

• 환경생물
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• 제40권4호
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• pp.641-650
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• 2022

본 연구의 목적은 양식장 배출수 내에 포함된 5종의 항생제(tetracycline, doxycycline, oxytetracycline, clindamycin 및 erythromycin)를 제거하기 위해 사용한 수중 비열 유전체장벽 방전 플라즈마(Dielectric Barrier Discharge plasma, DBD plasma) 장치 안으로 공기와 산소를 각각 주입했을 때 항생제의 제거효율을 비교하는 것이다. DBD plasma를 발생시키기 위해서 주어진 전압은 27.8 kV이었고, 처리간격은 0, 0.5, 1, 2, 4, 8, 16 및 32분이었다. 3종의 tetracycline계 항생제는 공기를 주입했을 때는 4분만에 유의하게 감소하였고, 산소를 주입했을 때는 30초만에 유의성을 나타내었다. 32분째 공기와 산소를 각각 주입한 결과, tetracycline은 78.1%와 95.8%, doxycycline은 77.1%와 96.3% 그리고 oxytetracycline은 77.1%와 95.5% 감소하였다. Clindamycin은 공기를 주입했을 때 59.6%가 감소되었고, 산소는 83.0% 감소되었다. 또한, erythromycin은 공기주입 시 53.3%가 감소되었고 산소 주입 시 74.3%가 감소하여 두 항생제 모두 tetracycline계 항생제보다 낮은 제거 효율을 보였다. 결론적으로 수중 DBD plasma는 양식장 배출수 내에 포함된 5종의 항생제를 감소시킬 수 있고, 제거 효율은 공기보다 산소를 주입하는 것이 더 효과적이다.

• 조명전기설비학회논문지
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• 제25권10호
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• pp.116-124
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• 2011

In this work, the effect of the initial concentration of methanol and ethanol, and the addition of oxygen molecules were discussed to improve the hydrogen generation using non-thermal plasma reactor effectively. In addition, the effect of ozone decomposition catalyst of manganese dioxide and its quantity was investigated. First, hydrogen concentration increased until an initial concentration of about 40,000[ppm] of methanol and thereafter it was saturated. Henceforth, hydrogen concentration decreased with increasing the oxygen percent on the carrier gas of nitrogen about both substances. Related with the effect of catalyst, it increased upto 60[g], but it was not changed largely after that. Consequently, it is confirmed that the hybrid process using plasma process and catalytic surface chemical reaction is a very promising way to increase the efficiency of hydrogen generation as investigated in this work.

• 한국응용과학기술학회지
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• 제31권4호
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• pp.541-548
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• 2014

This study was performed to obtain high conversion efficiency of $C_7H_8$ using non-thermal plasma and metal-supported catalyst. Adsorption-desorption characteristics of toluene was performed using 4A type (Zeolite) filled in a concentration reactor. Through this test, it was found that the concentration reactor has 0.020 g/g of adsorption capacity (at ambient temperature and pressure) and 3,600 ppm of desorption property at $150^{\circ}C$ (with in 20 min). In case of developed catalyst, toluene decomposition rate of Pd-AO (Pd coated catalyst) was better than Pd/Cu-AO and Pd/Ag-AO (Pd/Ag composite metal catalyst). Developed non-thermal plasma system was obtained flame amplification effect using injection process of desorbed tolune, and 98% of removal efficiency.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.208.2-208.2
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• 2016

Many researchers have paid attention to the studies on the interaction between non-thermal plasma and aqueous solutions for biomedical applications. The gas composition in the plasma is very important. Oxygen and nitrogen are the main gases of interest in biological applications. Especially, we focus on the oxygen concentration. In this experiment, we studied the role of oxygen concentration in plasma induced chemical reactions in solution. At first, the amount of ions are measured according to changing the oxygen concentration. And we checked the relationship between these ions and pH value. Secondly, when the oxygen concentration is changed, it identified the type and amount of radical generated by the plasma. In order to confirm the effect of these chemical property change to biological material, hemoglobin and RBCs are chosen. RBCs are one of the common basic biological cells. Thirdly, when plasma treated according to oxygen concentration in nitrogen feeding gas, oxidation of hemoglobin and RBC is checked. Finally, membrane oxidation of RBC is measured to examine the relation between hemoglobin oxidation and membrane damage through relative hemolysis and Young's modulus. Our results suggest that reactive species generated by the plasma differsdepending on the oxygen concentration changes. The pH values are decreased when oxygen concentration increased. OH decrease and NO increase are also observed. These reactive species makes change of chemical properties of solution. We also able to confirm that the difference in these reactive species to affect the oxidation of the Hb and RBCs. The Hb and RBCs are more oxidized with the high oxygen concentration conditions. But membrane is damaged more by plasma treatment with only nitrogen gas. It is shown that red blood cells membrane damage and oxidation of hemoglobin are not directly related.

• 한국대기환경학회지
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• 제30권6호
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• pp.577-585
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• 2014

A series of experiments using atmospheric-pressure non-thermal plasma coupled with transition metal catalysts were performed to remove ethylene from agricultural storage facilities. The non-thermal plasma was created by dielectric barrier discharge, which was in direct contact with the catalyst pellets. The transition metals such as Ag and $V_2O_5$ were supported on ${\gamma}-Al_2O_3$. The effect of catalyst type, specific input energy (SIE) and oxygen content on the removal of ethylene was examined to understand the behavior of the hybrid plasma-catalytic reactor system. With the other parameters kept constant, the plasma-catalytic activity for the removal of ethylene was in order of $V_2O_5/{\gamma}-Al_2O_3$ > $Ag/{\gamma}-Al_2O_3$ > ${\gamma}-Al_2O_3$ from high to low. Interestingly, the rate of plasma-catalytic ozone generation was in order of $V_2O_5/{\gamma}-Al_2O_3$ > ${\gamma}-Al_2O_3$ > $Ag/{\gamma}-Al_2O_3$, implying that the catalyst activation mechanisms by plasma are different for different catalysts. The results obtained by varying the oxygen content indicated that nitrogen-derived reactive species dominated the removal of ethylene under oxygen-lean condition, while ozone and oxygen atoms were mainly involved in the removal under oxygen-rich condition. When the plasma was coupled with $V_2O_5/{\gamma}-Al_2O_3$, nearly complete removal of ethylene was achieved at oxygen contents higher than 5% by volume (inlet ethylene: 250 ppm; gas flow rate: $1.0Lmin^{-1}$; SIE: ${\sim}355JL^{-1}$).