• 공업화학
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• 제25권5호
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• pp.497-502
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• 2014

상압 플라즈마 반응기 내에 Ni-$Al_2O_3$와 Ni-$MgAl_2O_4$ 촉매를 충진한 하이브리드 반응기를 이용하여 메탄과 이산화탄소의 전환반응을 진행하였다. 인가전력, 반응가스 유량, 혼합비율 및 반응기 온도 등 다양한 공정변수와 촉매의 충진 유무에 따른 메탄과 이산화탄소의 전환반응 특성이 분석되었다. 촉매의 반응 기여도 분석에서 공정온도를 $400^{\circ}C$까지 올린 경우에도 플라즈마 방전이 없이는 메탄과 이산화탄소의 촉매를 통한 자발적 전환반응이 일어나지 않았다. 이는 촉매를 충진하지 않은 플라즈마 방전만의 전환공정과의 비교를 통하여 확인할 수 있었다. 플라즈마 반응기에 촉매를 적용하는 경우에는 공정의 적절성과 전환처리에 적합한 촉매의 선택이 필수적이다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제51권12호
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• pp.567-572
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• 2002

In these days, diesel vehicle or power plant emits $NO_X\; and SO_2$ which cause air pollution like acid-rain, ozone layer destroy and optical smoke, therefore there are many kinds of methods considered for removing them such as SCR, catalyst, plasma process, and plasma-catalyst hybrid process. T$TiO_2$ is commonly used as catalyst to remove $NO_X$ gas because it have very excellent chemical characteristic as photo catalyst. In this paper, $NO_X$ sensing characteristic of $TiO_2$ thin film deposited by R.F Magnetron sputtering is investigated. A finger shaped electrode on $Al_2$O$_3$ substrate is designed and $TiO_2$ is deposited on the electrode by the magnetron sputtering deposition system. Chemical composition of the deposited $TiO_2$ thin film is $TiO_{1.9}$ by RBS analysis. When the UV is irradiated on it with flowing air, capacitance of $TiO_2$ thin film increases, however, when NO gas is put into the system with air, it immediately decreases because of photo chemical reaction. and it monotonously decreases with increasing NO concentration.

• Journal of Forest and Environmental Science
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• 제29권2호
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• pp.125-130
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• 2013

An attempt was made on pulp production from the fast growing plant, Acacia hybrid to determine the total yield, screened yield, Kappa number, and fibre morphology of organosolv Acacia hybrid pulp. Uniform-sized chips were taken to undergo pulping in a digester with five different concentrations of ethanol, 50%, 60%, 70%, 80% and 90% (v/v) with 1 M of sodium hydroxide as catalyst. All chips were digested in a temperature-controlled digester with constant amount of water added and temperature of $185^{\circ}C$ with the duration of three hours cooking time and correspond pressure 1.1-1.2 MPa. It was observed that increasing of ethanol concentration has led to pulp yield increment and decreased in the degree of delignification at the same time. This study was aimed to focus on the effect of the varied concentration of organic solvent towards the pulp yield and its relationship with Kappa number and pulp yield.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2010년도 제34회 춘계학술대회논문집
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• pp.202-205
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• 2010

이 연구에서는 아산화질소의 촉매 분해를 이용한 하이브리드 로켓의 자연 점화에 관한 연구를 수행하였다. 하이브리드 로켓은 촉매 점화기, 고체연료, 연소기, 노즐로 구성하였다. 아산화질소를 분해하기 위해 Ru 촉매를 $Al_2O_3$ 지지체에 함침법을 이용하여 담지하였고, 제조된 촉매의 반응온도에 따른 아산화질소 분해율을 측정하였다. 촉매 점화기의 작동조건에 따른 온도변화를 측정하였고, 하이브리드 로켓의 자연 점화에 대한 가능성을 확인하였다.

• 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.

• International Journal of Automotive Technology
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• 제2권2호
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• pp.63-75
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• 2001

This paper describes the development of THC reduction technologies compliant with SULEV regulations. Technologies embodied by the developmental work include improvement of fuel spray atomization, quick warm-up through coolant control shut of, and acceleration of fuel atomization for the fast rise of cylinder head temp inside the water jacket as well as the improvement of combustion state. The technologies likewise entail reduced HC while operating in lean A/F condition during engine warm-up with the cold lean burn technology, individual cylinder A/F control for improvement of catalytic converting efficiency, after-treatment such as thin-wall catalyst, HC-adsorber and EHC and etc, through vehicle application evaluation in cold start. We carried out an experimental as well as a practical study against SULEV regulations, and the feasibility of adopting these items in vehicle was likewise investigated.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2010년도 춘계학술대회 논문집
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• pp.462-463
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• 2010

• 한국입자에어로졸학회지
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• 제8권2호
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• pp.83-88
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• 2012

The electrical wire explosion process in liquid media is promising for nano-sized metal and/or alloy particles. The hybrid Pt/Fe-Cr-Al and Pt/Ni-Cr-Fe nanoparticles for exhaust emission control system are synthesized by electrical wire explosion process in liquid media. The alloy powders have spherical shape and nanometer size. According to the wire component, while Pt/Fe-Cr-Al nanoparticles are shown the well dispersed Pt on the Fe-Cr-Al core particle, Pt/Ni-Cr-Fe nanoparticles are shown the partially separated Pt on the Ni-Cr-Fe core particle. Morphologies and component of two kinds of hybrid nano catalyst particles were characterized by transmission electron microscope and energy dispersive X-ray spectroscopy analysis.

• Korean Chemical Engineering Research
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• 제50권2호
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• pp.343-347
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• 2012

충전형 저온 플라즈마 반응기 내에서의 가스 상 시안화합물의 분해특성을 반응기로 투입되는 방전 전력, 시안화합물의 유입농도, 운반기체인 공기의 습도 및 반응기 내의 충전물질 등을 변수로 연구하였다. 저온플라즈마 방전의 경우 시안화합물들의 분해는 트리클로로에틸렌에 비하여 상대적으로 매우 낮은 효율을 보였다. 그러나 플라즈마 방전 영역에 알루미나 또는 백금/알루미나 구슬을 충전한 경우 분해효율이 크게 높아졌으며 이는 플라즈마 반응과 더불어 백금/알루미나의 촉매작용에 의한 촉매 반응이 동시에 작용함에 기인한 것으로 판단된다.

• 대한금속재료학회지
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• 제49권8호
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• pp.596-600
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• 2011

Thermal degradation behavior of a $WO_3-TiO_2$ monolithic catalyst was investigated in terms of structural, morphological, and physico-chemical analyses. The catalyst with 4 wt.% $WO_3$ contents were prepared by a wet-impregnation method, and a durability test of the catalysts were performed in a temperature range between $400^{\circ}C$ and $800^{\circ}C$ for 3 h. An increase of thermal stress decreased the specific surface area, which was caused by grain growth and agglomeration of the catalyst particles. The phase transition from anatase to rutile occurred at around $800^{\circ}C$ and a decrease in the Brønsted acid sites was confirmed by structural analysis and physico-chemical analysis. A change in Brønsted acidity can affect to the catalytic efficiency; therefore, the thermal degradation behavior of the $WO_3-TiO_2$ catalyst could be explained by the transition to a stable rutile phase of $TiO_2$ and the decrease of specific surface area in the SCR catalyst.