• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.392-397
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• 2009

Gravity pressure vessels find their use in the wet oxidation of sewage sludge, which can be defined as the oxidation of organic and inorganic substances in an aqueous solution or suspension by means of oxygen or air at elevated pressures and temperatures. Numerical analyses were carried out for investigating the flow characteristics and wet air oxidation in the reaction vessel with various conditions such as supply oxidation and the supply positions of oxidation, etc. Wet air oxidation is promoted in the vicinity of bottom in the reactor with increase of oxygen supply. Also, it is the best condition to the oxidation supply position of 150 m and oxidation flow of 0.06 kg/s in the GPV reactor as the remnant of sludge and creation of organic acids.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1998년도 제28회 추계학술대회
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• pp.175-180
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• 1998

This paper describes evaluation of oxidation stability for diesel engine oils by Hot-tube oxidation tester at high temperature. Evaluation was rated by visual inspection of lacquer in capillary glass tube and TAN determination of used oil. Air, NO$_2$-air and SO$_2$-air mixed gases were used as oxidizing gas. One oil which has low oxidation stability is selected and reformulated by addition of some additives such as antioxidant, detergent and disperant to improve oxidation stability. As a results of reformulation, antioxidant and detergent was effective for improvement of high temperture oxidation stability on diesel engine oil.

• 한국환경보건학회지
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• 제3권1호
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• pp.53-56
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• 1976

The air oxidations of asphalt at temperatures ranging from 190$\circ$C to 270$\circ$C were studied for changes in physical properties, proportions and chemical characteristics of asphalt compositions, weak acid and very weak acid contents. The following results were obtained: 1) Oils and resins of asphalt components are oxidized to asphaltenes by blowing(Air oxidation) 2) At 270$\circ$C, asphaltenes begin to undergo a change into benzene insoluble after approximately 12 hours of air oxidation. 3) Weak acid increases at the oxidation temperature below 200$\circ$C. While very weak acid, presumably phenols, generally increases without regard to the blowing(Air oxidation) temperature.

• 상하수도학회지
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• 제20권4호
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• pp.487-498
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• 2006

The oxidation processes of metal catalysis were practically applied into the flexographic inks wastewater treatment to derive the most effective and economical system among all the processes of iron-salts coagulation, iron-catalyzed air oxidation, and coagulation followed by biological treatment. The iron concentration and pH were optimized as $2.8{\times}10^{-3}mol$ and 5.5~6.0, respectively, for all the oxidation processes. At the optimal reaction conditions, the removal efficiencies of $TCOD_{Mn}$ and Color were as follows for the respective process: i) 75% $TCOD_{Mn}$ and 77% Color removals for iron-salts coagulation, ii) 91% TCODMn and 90% Color removals for iron-catalyzed air oxidation, iii) 74~92% $TCOD_{Mn}$ and 81~90% Color removals for coagulation followed by biological treatment. Based on the economical and technological aspects, iron-catalyzed air oxidation was confirmed as the most effective process in the treatment of industrial wastewater.

• 한국결정성장학회지
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• 제15권2호
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• pp.57-60
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• 2005

[ $SiO_2$ ]로 산화된 웨이퍼 위에 상압화학기상증착 기술로 반도체 탄소나노튜브를 성장했으며, 이 나노튜브의 전기적 특성을 조사하였다. 전기적 특성은 반도체 탄소나노튜뷰를 $300^{\circ}C$, 대기 중에서 산화 열처리 시간을 변화시키면서 상온대기에서 측정하였다. 반도체 탄소나노튜브는 $300^{\circ}C$에서 산화 열처리 시간을 증가할수록 점차적으로 금속 탄소나노튜브로 변형되는 것을 보았다. 탄소나노튜브는 $300^{\circ}C$, 대기에서 6시간 동안 산화 열처리 후 표면의 일부가 없어지는 현상을 투과 전자현미경으로 확인하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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• pp.126-127
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• 2005

Semiconductor carbon nanotube was grown on oxided silicon wafer with Atmosphere Pressure Chemical Vapor Deposition (APCVD) ethmod and investigated the electrical property after thermal oxidation at 300$^{\circ}C$ in air. The electrical property was measured at room temperature in air after thermal oxidation at 300$^{\circ}C$ for various times in air. Semiconductor carbon nanotube was steadily changed to metallic carbon nanotube as increasing of thermal oxidation times at 300$^{\circ}C$ in air.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2013년도 춘계학술대회 논문집
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• pp.112-113
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• 2013

Thin CrAlMgSiN films, whose composition were 30.6Cr-11.1Al-7.3Mg-1.2Si-49.8N (at.%), were deposited on steel substrates in a cathodic arc plasma deposition system. They consisted of alternating crystalline Cr-N and AlMgSiN nanolayers. After oxidation at $800^{\circ}C$ for 200 h in air, a thin oxide layer formed by outward diffusion of Cr, Mg, Al, Fe, and N, and inward diffusion of O ions. Silicon ions were relatively immobile at $800^{\circ}C$. After oxidation at $900^{\circ}C$ for 10 h in air, a thin $Cr_2O_3$ layer containing dissolved ions of Al, Mg, Si, and Fe formed. Silicon ions became mobile at $900^{\circ}C$. After oxidation at $900^{\circ}C$ for 50 h in air, a thin $SiO_2-rich$ layer formed underneath the thin $Cr_2O_3$ layer. The film displayed good oxidation resistance. The main factor that decreased the oxidation resistance of the film was the outward diffusion and subsequent oxidation of Fe at the sample surface, particularly along the coated sample edge.

• 대한화학회지
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• 제55권5호
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• pp.842-845
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• 2011

Wet air oxidation (WAO) of oily sludge was carried out using $Fe^{3+}$ as catalyst, placed in a 0.5 L batch autoclave in the temperature range of $250-330^{\circ}C$. Experiments were conducted to investigate the effects of temperature, the initial COD, reaction time, concentration of catalyst and $O_2$ excess (OE) on the oxidation of the oily sludge. The results showed that in the WAO 88.4% COD was achieved after 9 min reaction at temperature of $330^{\circ}C$, OE of 0.8 and the initial COD of 20000 mg/L. Temperature was found to have a significant impact on the oxidation of oily sludge. Adding a catalyst significantly improved the COD removal. Homogenous catalyst, $Fe^{3+}$, showed effective removal for pollutants. COD removal was 99.7% in the catalytic wet air oxidation (CWAO) over $Fe^{3+}$ catalyst. The results proved that the CWAO was an effective pretreatment method for the oily sludge.

• 대한전자공학회논문지SD
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• 제40권5호
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• pp.285-289
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• 2003

본 논문에서는 실리콘 기판상의 전송선로 특성을 개선하기 위하여 표면 마이크로머시닝 기술과 새로운 산화법(H₂O/O₂ 분위기에서 500℃, 1시간 열산화와 1050℃, 2 분간 RTO(Rapid Thermal Oxidation) 공정)을 이용하여 10 ㎛ 두께의 다공질 실리콘 산화막(oxidized porous silicon:OPS) air-bridge 기판 위에 공면 전송선로(Coplanar Waveguide:CPW)를 제작하였다. 간격이 40 ㎛ 신호선이 20 ㎛ 전송선 길이가 2.2 mm인 CPW air-bridge 전송선의 삽입손실은 4 GH에서 -0.28 dB이며, 반사손실은 -22.3 유를 나타내었다. OPS air-bridge 위에 형성된 CPW의 손실이 OPS층 위에 형성된 CPW의 삽입손실보다 약 1 dB 정도 적은 것을 보여주었으며, 반사손실은 35 GHz 범위에서 약 -20 dB를 넘지 않고 있다. 이와 같은 결과로부터 두꺼운 다공질 실리콘 멤브레인 및 air-bridge 구조는 고 저항 실리콘 집적회로 공정에서 고성능, 저가의 마이크로파 및 밀리미터파 회로 응용에 충분히 활용 될 수 있으리라 기대된다.

• 대한화학회지
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• 제10권2호
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• pp.76-90
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• 1966

Ammonium sulfate synthesized by the air oxidation methods without catalyst using the reaction vessel which was fitted with fritted glass at the bottom of it and introducing, through the bottom, ammonia and air with constant flow rates to sulfurous acid solution of constant concentrations at the given temperatures. The experiment showed that the oxidation process was accelerated in accord with the increase of the air flow rates when the ammonia flow rate was constantly kept at ca. 100ml/min. in high temperatures. When the pH of the solution reached 9.0, the oxidation was nearly completed. It is assumed that in the process of reaction, $[O_{2}{\to}HSO_{3}^-]^{\neq}$ would be produced as an activated complex and the reaction was thought to be first order. The experiment indicated that the 0.5M sulfurous solution could be oxidized up to 98.54% at the flow rates of ammonia and air, 100ml/min., and 4l/min., respectively at $50^{\circ}C$.