• Nuclear Engineering and Technology
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• 제56권6호
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• pp.2307-2316
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• 2024

A melting failure of W monoblock components of the upper divertor outer target in EAST occurred during the plasma campaigns in 2019. The failure characters and microstructure evolution of the failed W monoblock have been well investigated on one string (W436 string). Near the strike point region where heat flux density is highest, macroscopic cracks and severe surface damage such as dimensional change, melting and solidification are visible in several W monoblocks. At the same time, debonding, melting and migration of Cu/CuCrZr cooling tube components introduced fatal damage to the structure and function. The heat-induced microstructure evolution in the rest part has been examined via hardness tests and metallography. From the heat flux surface to the cooling tube, hardness increased gradually and the recrystallized grains could be found in the region with the highest temperature, while recrystallization grains also appear in some W monoblocks near the cooling tube area. The detailed microstructure has been investigated by metallography and EBSD. Such cases in EAST provide experiences on the extreme condition of accidental loss of coolant or higher discharge power in future devices.

• KSBB Journal
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• 제30권1호
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• pp.21-26
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• 2015

Plasma is an ionized gas mixture, consisting of neutral particles, positive ions, negative electrons, electronically excited atoms and molecules, radicals, UV photons, and various reactive species. Also, plasma has unique physical properties distinct from gases, liquids, and solids. Until now, non-thermal plasmas have been widely utilized in bio-medical applications (called bio-plasma) and have been developed for the plasma-related devices that are used in the medical field. Although numerous bio-plasma studies have been performed in biomedicine, there is no confirmation of the nonthermal effect induced by bio-plasma. Standardization of the biological application of plasma has not been evaluated at the molecular level in living cells. In this context, we investigated the biological effect of bio-plasma on living cells. Hence, we treated the fibroblasts with Dielectric Bauvier Discharge bio-plasma (DBD), and assessed the characteristic change at the molecular level, one of the typical cellular responses. Heat shock protein 70 (HSP70) regulates its own protein level in response to stimuli. HSP70 responds to heat shock by increasing its own expression at the molecular level in cells. Hence, we confirmed the level of HSP70 after treatment of mouse embryonic fibroblasts (MEFs) with DBD. Interestingly, DBD-plasma induced cell death, but there was no difference in the level of HSP70, which is induced by heat shock stimuli, in DBD-treated MEFs. Our data provide the basic information on the interaction between MEFs and DBD, and can help to design a molecular approach in this field.

• 한방안이비인후피부과학회지
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• 제15권1호
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• pp.198-218
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• 2002

On the basis of Imjeungjinamuian(臨證指南醫案), authors investigated the pathogenesis and treatment of ophthalmotolaryngobgic diseases from the viewpoint of Onbyeong(溫病). 1. The symptoms and diseases investigated according to department were as follows;. 1) Ophthalmology : blepharitis, blepharedema, lacrimal hypersecretion, hyperemia, ophthalmalgla, photopsia, visual disturbance, mydriasis 2) Otology : full-feeling, otorrhea, otalgla, mastoiditis, tinnitus, hearing disturbance, vertigo 3) Rhinology : rhinorrhea, nasal obstruction, sinusitis, epistaxis 4) Laryngology : sore throat, hoarseness 5) The Others : headache, cough, asthma 2. The pathogenesis and treatment of ophthalmotolaryngologic diseases were as follows. 1) When the pathogenesis of hyperemia, otorrhea, otalgia, mastoiditis, hearing disturhance. epistaxis, sore throat, headache and cough are wind-stagnanc(風鬱), wind-warm(風溫), wind-fire(風火), wind-dryness(風燥), dryness-heat(燥熱), the treatment of pungent-cool-evaporating(辛凉解表) with Dajosan(茶調散), Mori Folium(桑葉), Lonicerae Flos(金銀花), Forsythiae Fructus(連翹), Viticis Fructus(蔓荊子), Prunellae Spica(夏枯草), Arctii Fructus(牛蒡子), etc can be applied. 2) When the pathogenesis of hoarseness, cough and asthma are cold(寒), cold with endogenous heat(寒包熱, 外冷內熱), water retention(水邪), fluid retention(伏飮), impairment of YangKi by overexertion(勞傷陽氣), the treatment of pungent-warm-evaporating(辛溫解表) with Mahaenggamseoktang(麻杏甘石湯), Socheongryongtang(小靑龍湯), Jeongryeokdaejosapyetang(정력대조사폐탕), Gyejitang(桂枝湯), Armeniacae Amarum Semen(杏仁), etc can be applied. 3) When the pathogenesis of photopsia, otorrhea, otalgia, rhinorrhea, sinusitis, epistaxis, sore throat, hoarseness, headache and cough are stagnancy-induced heat(鬱熱), wind-dryness(風燥), wind-heat(風熱), summer heat(暑熱), summer wind(暑風), insidious summer heat(伏暑), autumn heat(秋暑), autumn wind(秋風), autumn dryness(秋燥), dryness-heat(燥熱), heat in Ki system(氣分熱), insidious warm(溫伏), brain discharge by fire in Ki system(氣火 腦熱), heat in stomach(胃熱), endogenous fire by deficiency of Yin(陰虛內火), deficiency of Yin in stomach(胃陰虛), the treatment of Ki-cooling(淸氣) with Bangpungtongseongsan(防風通聖散), Ikweonsan(益元散), Gyejibaekhotang(桂枝白虎湯), Geumgwemaekmundongtang(금궤맥문동탕), Gyeongokgo(瓊玉膏), Sojae Semen Praeparatum(두시), Scutellariae Radix(黃芩), Phyllostachys Folium(竹葉), Adenophorae Radix(沙參), Mori Cortex(桑白皮), Fritillariae Cirrhosae Bulbus(貝母), etc can be applied. 4) When the pathogenesis of blepharitis, hyperemia, ophthalmalgia, full-feeling, otorrhea, otalgia, tinnitus, hearing disturbance, sinusitis, hoarseness, headache and cough are fire in liver(肝火), fire in gallbladder(膽火), ministerial fire in Soyang system(少陽相火), wind-stagnancy(風鬱), stagnancy-induced fire(鬱火), brain discharge by phlegm-fire(痰火 腦熱), the treatment of mediation(和解) with Gardeniae Fructus(梔子), Moutan Cortex(牧丹皮), Saigae Tataricae Cornu(羚羊角), Artemisiae Annuae Herba(靑蒿), Cyperi Rhizoma(香附子), Poria(적복령), etc can be applied. 5) When the pathogenesis of blepharedema and cough are dampness in both spleen and lung(脾肺濕) damp-heat(濕熱), damp-phlegm(濕痰), the treatment of dampness-resolving(化濕) with Poria(백복령), Coicis Semen(薏苡仁), Tetrapanacis Medulla(通草), Armeniacae Amarum Semen(杏仁), Talcum(滑石), etc can be applied. 6) When the pathogenesis of vertigo and cough are deficiency of Yong(營虛), heat in Yong, system(營熱), the treatment of Yong-cooling(淸營) with Rehmanniae Radix(生地黃), Liriopis Tuber(麥門冬), Biotae Semen(柏子仁), Lilii Bulbus(百合), Phyllostachys Folium(竹葉), etc can be applied. 7) When the pathogenesis of epistaxis are heat in blood system of heart(心血熱), reversed flow of fire(火上逆), overexertion(努力), the treatment of blood-cooling(凉血) with Rhinoceri Cornu(犀角), Rehmanniae Radix(生地黃), Moutan Cortex(牧丹皮), Salviae Miltiorrhizae Radix(丹參), Scrophulariae Radix(玄蔘), etc can be applied. 8) When the pathogenesis of nasal obstruction is pathogen-stagnancy(邪鬱), the treatment of resuscitation(開竅) with Sosang(少商, LU11) acupuncture can be applied. When the pathogenesis of hoarseness is evil Ki(穢濁), the treatment of resuscitation(開竅) with Arctii Fructus(牛蒡子), Lasiosphaera Seu Calvatia(馬勃), Curcumae Radix(鬱金), etc can be applied. When the pathogenesis of headache is stasis of both Ki and blood(氣血瘀痺), the treatment of resuscitation(開竅) with Cnidii Rhizoma(川芎), Asari Herba Cum Radice(細辛), Scorpio(全蝎), moxibustion(灸), etc can be applied. 9) When the pathogenesis of lacrimal hypersecretion, visual disturbance, mydriasis, tinnitus, hearing disturbance, sinusitis, epistaxis, hoarseness and cough are deficiency of Yin(陰虛), deficiency of kidney(腎虛), deficiency of both liver and kidney(肝腎虛), deficiency of both heart and kidney(心腎虛), brain discharge by deficiency of Yin(陰虛 腦熱), exuberance of Yang in liver(肝陽上亢), overexertion(勞損), the treatment of Yin-replenishing(滋陰) with Yukmijihwanghwan(六味地黃丸), Hojamhwan(虎潛丸), Jeobutang(猪膚湯), Lycii Fructus(枸杞子), Polygoni Multiflori Radix(何首烏), Rehmanniae Radix(生地黃), Schizandrae Fructus(五味子), Liriopis Tuber(麥門冬), Asini Gelatinum(阿膠), etc can be applied. 10) When the pathogenesis of ophthalmalgia, mydriasis, vertigo and headache are deficiency of Yin in liver(肝陰虛), exuberance of Yang in liver(肝陽上亢), endogenous wind(內風), excess in upper and deficiency in lower part(上實下虛), the treatment of Yin-replenishing(滋陰) and endogenous wind-calming(熄風) with Rehmanniae Radix Preparat(熟地黃), Lycii Fructus(枸杞子), Polygoni Multiflori Radix(何首烏), Paeoniae Radix Alba(白芍藥), Ostreae Concha(牡蠣), Saigae Tataricae Cornu(羚羊角), Chrysanthemi Flos(菊花), etc be applied. 11) When the pathogenesis of mydriasis, sinusitis, hoarseness, headache, cough and asthma are exhaustion of vital essence(精氣無收藏), brain discharge(腦髓不固), floating Yang(陽虛浮), exsanguination(失血), deficiency of both Yin and Yang(陰陽不足), overexertion(勞損), deficiency of Yang in kidney(腎陽虛), the treatment of Yang-restoring and exhaustion-arresting(回陽固脫) with Yangyeongtang(養營湯), Cheonjinhwan(天眞丸), Bokmaektang(복맥탕), Geonjungtang(建中湯), Dogihwan(都氣丸), Singihwan(腎氣丸), Jinmutang(眞武湯), Ostreae Concha(牡蠣), Nelumbinis Semen(蓮子肉), etc can be applied. 12) When the pathogenesis of lacrimal hypersecretion, vertigo and headache are deficiency of stomach and endogenous wind(胃虛內風), endogenous wind with phlegm(內風挾痰), liver check of stomach(肝木橫擾), the treatment of concomitant-treating of both liver and stomach(肝胃同治) with Paeoniae Radix Alba(白芍藥), Uncariae Ramulus Et Uncus(釣鉤藤), Gastrodiae Rhizoma(天麻), Astragali Radix(황기), Pinelliae Rhizoma(半夏), etc can be applied. When the pathogenesis of asthma is failure of kidney to promote inspiration(腎不納氣), the treatment of kidney-tonifing and inspiration-promoting(補腎納氣) with Singihwan(腎氣丸), Psoraleae Fructus(補骨脂), Juglandis Semen(胡桃), Aquilariae Resinatum Lignum(沈香), etc can be applied. When the pathogenesis of asthma is deficiency of Ki(氣虛), the treatment of Ki-reinforcing(補氣) with Sagunjatang(四君子湯), Insamgeonjungtang(人參建中湯), etc can be applied.

• 한국수소및신에너지학회논문집
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• 제31권1호
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• pp.132-137
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• 2020

Lithium secondary batteries have become an important power source for portable electronic devices such as cellular phones, laptop computers. Presently, commercialized lithium-ion batteries use a LiCoO₂ cathode. However, due to the high cost and environmental problems resulting from cobalt, an intensive search for new electrode materials is being actively conducted. Recently, solid solution LiMn_1-xNi_xO₂ have become attractive because of high capacity and enhanced safety at high voltages over 4.5 V. The Li_1.6Ni_0.35Mn_0.65O₂ compounds were conventionally prepared by a sol-gel method, which can produce the layered Li-Ni-Mn-O compounds with a high homogeneity. And by adding a graphene 2wt% the first charge-discharge voltage profiles was increased over Li_1.6Ni_0.35Mn_0.65O₂ compound. Also, the variation s of the discharge capacities with cycling showed a higher capacity retention rater. In this study, material lifecycle evaluation was performed to analyze the environmental impact characteristics of Li_1.6Ni_0.35Mn_0.65O₂ & graphene 2wt% half-cell manufacturing process. The software of material life cycle assessment was Gabi. Through this, environmental impact assessment was performed for each process. The environmental loads induced by Li_1.6Ni_0.35Mn_0.65O₂ & graphene 2wt% synthesis process were quantified and analyzed, and the results showed that the amount of power had the greatest impact on the environment.

• 한국결정성장학회지
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• 제22권4호
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• pp.194-199
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• 2012

스피넬 구조로 이루어진 $LiMn_2O_4$에서 Mn의 일부분을 Ni로 치환한 $LiMn_{1.5}Ni_{0.5}O_4$은 4.7 V 전압 영역에서 높은 방전 용량 및 우수한 충 방전 사이클 특성을 가진다. 본 연구에서는 착체중합법을 이용하여 $LiMn_{1.5}Ni_{0.5}O_4$를 합성하였다. Citric acid : metal의 몰비(5 : 1, 10 : 1, 15 : 1, 30 : 1) 및 하소 온도($500{\sim}900^{\circ}C$) 변화에 따라 합성된 $LiMn_{1.5}Ni_{0.5}O_4$ 분말의 특성을 조사하였다. 합성된 분말의 XRD 분석을 통해 저온($500^{\circ}C$) 및 고온($900^{\circ}C$) 영역에서 모두 단일상인 $LiMn_{1.5}Ni_{0.5}O_4$ 결정상을 관찰할 수 있었고, 하소 온도가 증가함에 따라 결정화 및 결정자 크기도 함께 증가하였다. 합성된 $LiMn_{1.5}Ni_{0.5}O_4$ 분말의 형상 및 비표면적 분석 결과, 저온영역에서는 CA 몰비가 증가할수록 입자사이즈는 감소하고 비표면적은 증가하는 것을 확인할 수 있었다. 반면에 고온영역에서는 온도 증가에 따른 입자 성장에너지가 CA 몰비 증가에 따른 입자 사이즈 감소 및 비표면적 증가 효과를 감소시키는 것을 관찰하였다.

• 한국해안·해양공학회논문집
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• 제25권2호
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• pp.76-93
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• 2013

영산강 하구는 하구둑 및 방조제 건설등의 개발 사업으로 해수유동 체계에 변화가 발생하였으며, 인위적인 하구둑 운영에 의해서 담수 방류가 조절되어 자연적인 하구와는 다른 하구순환 형태를 나타내며, 하천 기원 퇴적물의 유입이 제한적이다. 하구둑 방류가 빈번한 하계의 하구 퇴적물 이동양상과 수지를 파악하기 위하여 3차원 수치모델인 EFDC를 적용하였다. 외력 및 육상 유입 조건을 실시간으로 입력하고, 연구지역의 퇴적물 입도특성을 바탕으로 모래, 실트, 점토의 다중 입경을 적용하여 모델링을 수행하였다. 관측 조석, 조류와 부유사 농도에 대하여 보정 검정된 모델링 결과에 의하면, 2011년 8월에 부유 퇴적물은 표층에서 외해방향으로 이동하지만 중 저층에서는 하구 내측으로 이동한다. 하구둑 방류에 기인한 하구순환에 의해 실트 크기 입자에 의한 퇴적이 우세하게 나타나며, 점토 크기 입자는 대부분 하구 내에서 순환을 반복하는 양상을 보였다.

• 한국분말재료학회지
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• 제13권5호
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• pp.327-335
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• 2006

In the development of new hydrogen absorbing materials for a next generation of metal hydride electrodes for rechargeable batteries, metastable Mg-Ni-based compounds find currently special attention. Amor phous-nanocrystalline $Mg_{63}Ni_{30}Y_7$ and $Mg_{50}Ni_{30}Y_{20}$ alloys were produced by mechanical alloying and melt-spinning and characterized by means of XRD, TEM and DSC. On basis of mechanically alloyed Mg-Ni-Y powders, complex hydride electrodes were fabricated and their electrochemical behaviour in 6M KOH (pH=14,8) was investigated. The electrodes made from $Mg_{63}Ni_{30}Y_7$ powders, which were prepared under use of a SPEX shaker mill, with a major fraction of nanocrystalline phase reveal a higher electrochemical activity far hydrogen reduction and a higher maximum discharge capacity (247 mAh/g) than the electrodes from alloy powder with predominantly amorphous microstructure (216 mAh/g) obtained when using a Retsch planetary ball mill at low temperatures. Those discharge capacities are higher that those fur nanocrystalline $Mg_2Ni$ electrodes. However, the cyclic stability of those alloy powder electrodes was low. Therefore, fundamental stability studies were performed on $Mg_{63}Ni_{30}Y_7$ and $Mg_{50}Ni_{30}Y_{20}$ ribbon samples in the as-quenched state and after cathodic hydrogen charging by means of anodic and cathodic polarisation measurements. Gradual oxidation and dissolution of nickel governs the anodic behaviour before a passive state is attained. A stabilizing effect of higher fractions of yttrium in the alloy on the passivation was detected. During the cathodic hydrogen charging process the alloys exhibit a change in the surface state chemistry, i.e. an enrichment of nickel-species, causing preferential oxidation and dissolution during subsequent anodization. The effect of chemical pre-treatments in 1% HF and in $10\;mg/l\;YCl_3/1%\;H_2O_2$ solution on the surface degradation processes was investigated. A HF treatment can improve their anodic passivation behavior by inhibiting a preferential nickel oxidation-dissolution at low polarisation, whereas a $YCl_3/H_2O_2$ treatment has the opposite effect. Both pre-treatment methods lead to an enhancement of cathodically induced surface degradation processes.

• Carbon letters
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• 제28권
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• pp.31-37
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• 2018

This paper examines a simple one-step and catalyst-free method for synthesizing carbon nanoparticles from aliphatic alcohols and n-hexane with linear molecule formations by using a stable solution plasma process with a bipolar pulse and an external resistor. When the external resistor is adopted, it is observed that the current spikes are dramatically decreased, which induced production of a more stable discharge. Six aliphatic linear alcohols (methanol-hexanol) containing carbon with oxygen sources are studied as possible precursors for the massive production of carbon nanoparticles. Additional study is also carried out with the use of n-hexane containing many carbons without an oxygen source in order to enhance the formation of carbon nanoparticles and to eliminate unwanted oxygen effects. The obtained carbon nanoparticles are characterized with field emission-scanning electron microscopy, energy dispersive X-ray spectroscopy, and Raman spectroscopy. The results show that with increasing carbon ratios in alcohol content, the synthesis rate of carbon nanoparticles is increased, whereas the size of the carbon nanoparticles is decreased. Moreover, the degree of graphitization of the carbon nanoparticles synthesized from 1-hexanol and n-hexane with a high carbon (C)/oxygen (O) ratio and low or no oxygen is observed to be greater than that of the carbon nanoparticles synthesized from the corresponding materials with a low C/O ratio.

• Parasites, Hosts and Diseases
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• 제52권6호
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• pp.667-672
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• 2014

While imported falciparum malaria has been increasingly reported in recent years in Korea, clinicians have difficulties in making a clinical diagnosis as well as in having accessibility to effective anti-malarial agents. Here we describe an unusual case of imported falciparum malaria with severe hemolytic anemia lasting over 2 weeks, clinically mimicking a coinfection with babesiosis. A 48-year old Korean man was diagnosed with severe falciparum malaria in France after traveling to the Republic of Benin, West Africa. He received a 1-day course of intravenous artesunate and a 7-day course of Malarone (atovaquone/proguanil) with supportive hemodialysis. Coming back to Korea 5 days after discharge, he was readmitted due to recurrent fever, and further treated with Malarone for 3 days. Both the peripheral blood smears and PCR test were positive for Plasmodium falciparum. However, he had prolonged severe hemolytic anemia (Hb 5.6 g/dl). Therefore, 10 days after the hospitalization, Babesia was considered to be potentially coinfected. A 7-day course of Malarone and azithromycin was empirically started. He became afebrile within 3 days of this babesiosis treatment, and hemolytic anemia profiles began to improve at the completion of the treatment. He has remained stable since his discharge. Unexpectedly, the PCR assays failed to detect DNA of Babesia spp. from blood. In addition, during the retrospective review of the case, the artesunate-induced delayed hemolytic anemia was considered as an alternative cause of the unexplained hemolytic anemia.

• 한국안전학회지
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• 제15권2호
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• pp.70-77
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• 2000

For hazardous air pollutants(HAP) such as NO, $NO_2$ and $SO_2$ decomposition efficiency, power consumption, and applied voltage were investigated by SPCP(Surface induced discharge Plasma Chemical Processing) reactor to obtain optimum process variables and maximum decomposition efficiencies. Decomposition efficiency of HAP with various electric frequencies(5~50 kHz), flow rates(100~1,000 mL/min), initial concentrations(100~1,000 ppm) and additive($CH_4$) were measured and the products were analyzed with FT-IR. Experimental results showed that for the frequency of 10 kHz, the highest decomposition efficiency of 94.3 % for NO, 84.7 % for $NO_2$ and 99 % far $SO_2$ were observed at the power consumptions of 19.8, 20 and 19W, respectively, and that decomposition efficiency decreased with increasing frequency above 20 kHz. And decomposition efficiency per unit power were 5.21 %/W for $SO_2$, 4.76 %/W for NO and 4.24 %/W for $NO_2$ and the highest decomposition efficiency was observed with $SO_2$. Decomposition efficiency was increased with increasing residence times and with decreasing initial concentration of pollutants. When the additive of $CH_4$ was used, decomposition efficiency was increased with increasing $CH_4$ content, and NO, $NO_2$ and $SO_2$ were almost completely decomposed with the efficiency of 99 %, 98 % and 99 %, respectively and therefore $CH_4$ was a good additive material. The optimum power for the maximum decomposition efficiency were 7.5 W for $SO_2$, 9.5 W for NO and 15.5 W for $NO_2$, respectively. Optimum power with the maximum decomposition efficiency were 9.5 W at 1,000 ppm of NO, 7~8 W at 100~500 ppm of NO and 15.5 W at all concentration range of $NO_2$ and 11.5 W at 1,000 ppm, 4.9 W at 500 ppm, 3.7 W at 100~300 ppm of $SO_2$ and power efficiency was best in these case.