• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.9
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• pp.765-770
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• 2003

We have developed a low-temperature, and low-pressure radical induced oxidation (RIO) technology, so that high-quality ultrathin silicon dioxide layers have been effectively produced with a high reproducibility, and successfully employed to realize high performace SiGe heterostructure complementary MOSFETs (HCMOS) lot the first time. The obtained oxide layer showed comparable leakage and breakdown properties to conventional furnace gate oxides, and no hysteresis was observed during high-frequency capacitance-voltage characterization. Strained SiGe HCMOS transistors with a 2.5 nm-thick gate oxide layer grown by this method exhibited excellent device properties. These suggest that the present technique is particularly suitable for HCMOS devices requiring a fast and high-precision gate oxidation process with a low thermal budget.

• Journal of the Korean institute of surface engineering
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• v.36 no.4
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• pp.329-333
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• 2003

The high-temperature oxidation behavior of Ti39Al-10V alloy that consisted primarily of $\beta$-Ti, ${\gamma}$-TiAl, and $\alpha_2$ $-Ti_3$Al phases was studied. The relatively thick and porous oxide scales formed consisted primarily of an outermost, thin TiO$_2$ layer, and an outer, thin $Al_2$$O_3$-rich layer, and an inner, very thick (TiO$_2$, $Al_2$$O_3$) mixed layer. Vanadium was present uniformly throughout the oxide scale. The formation and subsequent evaporation of V-oxides such as VO, $VO_2$, and $V_2$O$_{5}$ deteriorated oxidation resistance and scale adherence of the TiAl alloy significantly.y.

• 한국연소학회:학술대회논문집
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• 2004.11a
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• pp.225-230
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• 2004

Volatile organic compounds (VOCs) are low calorific value gases (LCVG) emitted from chemical processes such as painting booth, dye works and drying processes etc. Characteristics of VOCs are low calorific values less than 150 kcal/$m^3$, high activation energy for ignition and low energy output. These characteristics usually make combustion unstable and its treatment processes needs high-energy consumption, The cyclone combustion system is suitable for LCVG burning because it can recirculate energy through a high swirling flow to supply the activation energy for ignition, increases energy density to make a combustion temperature higher than usual swirl combustor and also increases mixing intensity, This research was conducted to develop optimized cyclone combustion system for thermal oxidation of VOCs. This research was executed to establish the effect of swirl number with respect to the combustion temperature and composition of exhausted gas in the specific combustor design.

• International Journal of Safety
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• v.1 no.1
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• pp.58-61
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• 2002

A preparation method of cobalt supported alumina catalyst for a emergency escape mask cartridge has been studied. Catalysts were prepared by incipient wetness impregnation method using pre-shaped $\gamma$=alumina powders of 70-100 mesh. The catalyst was tested in a continuous-flow reactor system and characterized by elemental analysis, BET and TGA-DTA techniques. Cobalt shows higher activity than platinum or nickel for carbon monoxide oxidation at room temperature. Optimum loading amount of cobalt was 10 wt.% for CO oxidation and the reaction activity increases gradually with the increase of calcination temperature up to $450^{\circ}C.

• Journal of Korean Society for Atmospheric Environment
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• v.6 no.1
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• pp.57-72
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• 1990

The oxidation of carbon monoxide on a catalyst, $LaSrNiCoO_3$ was investigatigated with a plug flow system. Kinetic quantities such as reaction-rate, reaction order and Arhenius-parameters at various reactor temperature from 200$^\circ$C to 300$^\circ$C were determined. Also, the optimum condition for the oxidation of carbon monoxide with this catalyst was determined and are as follows. Partial pressure of oxigen ; 428mmHg Partial pressure of carbon monoxide ; 332mmHg Mixed moral ratio of oxigen and Carbon monoxide ; 1.3 : 1 Total gas flow ; 224ml/min Reaction temperature ; 340$^\circ$C The reaction kinetic equation at the optimum condition, temperature range from 200$^\circ$C to 340$^\circ$C, are as follow. $$ $v = Ae^{6.5Kcal/RT} [CO]^{0.93 \sim 0.98} [O_2]^{0.42 \sim 0.50}$ $$ In addition to this, numerical calculation were performed to evaluate the mass and heat transfer effect on this system.

• Journal of the Korean institute of surface engineering
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• v.30 no.5
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• pp.320-332
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• 1997

The development of colored surface on zinc coating by the oxidation of a melten alloy of zinc with a minor amount of oxygen-avid additive such as tianium has been studied. Using a galvanizing Zinc alloy containing 0.1 to 0.3wt%Ti, gold, purple or blue color was developed clearly and stably, depending upon the extent of oxidation, by air cooling after hot dipping in a bath at temperature of $550^{\circ}C$ to $600^{\circ}C$. The source of the color is light interference with surface oxide layer. THe final color depends on the thickness of the color depends on the thickness of $TiO_2$, played So compositing, temperature and time at elevated temperature after are all controlling variables. Since oxidation film such as $TiO_2$ played role of passivation film, the corrosion resistance in a colored galvanized steel sheet. It is also thought that surface oxide layer of $TiO_2$ inhibited dissolution of the coating layer.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.107-107
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• 2016

TiCrAlSiN films were developed in order to improve the high-temperature oxidation resistance, corrosion resistance, and mechanical properties of conventional TiN films that are widely used as hard films to protect and increase the lifetime and performance of cutting tools or die molds. In this study, a nano-multilayered TiAlCrSiN film was deposited by cathodic arc plasma deposition. It displayed relatively good oxidation resistance at $700-900^{\circ}C$, owing to the formation protective oxides of $Al_2O_3$, $Cr_2O_3$, and $SiO_2$, and semiprotective $TiO_2$. At $1000^{\circ}C$, the increased temperature led to the formation of the imperfect oxide scale that consisted primarily of the outer ($TiO_2$,$Al_2O_3$)-mixed scale and inner ($TiO_2$, $Al_2O_3$, $Cr_2O_3$)-mixed scale.

• Journal of the Korean Ceramic Society
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• v.29 no.10
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• pp.785-790
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• 1992

A study of the pack cemcented SiC coating on graphite was performed and the process conditions were evaluated by means of experimental design. The content of Si, P2O5, B and Al2O3 reaction temperature, reaction time and acid treatment wast tested as the experimental variables. The results were analyzed and compared by the characteristic value of 10% weight loss by oxidation. The acid treatment exhibited the most effective anti-oxidation property and the optimum conditions were the powder composition of 20% Si, 3% B and 77% SiC, the reaction temperature of 1550$^{\circ}C$ for 7 hours with phosphoric acid treatment. The pack coating performed under this condition improved the 10% weight loss oxidation temperature by 514$^{\circ}C$ compared to the bare graphite.

• Journal of the Korean Magnetics Society
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• v.14 no.3
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• pp.99-104
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• 2004

We have studied to understand the barrier and interface qualities and structural changes through measuring temperature dependent spin-polarization as functions of plasma oxidation time and annealing time. Magnetic tunnel junctions consisting of SiO2$_2$/Ta 5/CoFe 17/IrMn 7.5/CoFe 5/Al 1.6-Ox/CoFe 5/Ta 5 (numbers in nm) were deposited and annealed when necessary. A 30 s,40 s oxidized sample showed the lowest spin-polarization values. It is presumed that tunneling electrons were depolarized and scattered by residual paramagnetic Al due to under-oxidation. On the contrary, a 60s, 70 s oxidized sample might have experienced over-oxidation, where partially oxidized magnetic dead layer was formed on top of the bottom CoFe electrode. The magnetic dead layer is known to increase the probability of spin-flip scattering. Therefore it showed a higher temperature dependence than that of the optimum sample (50 s oxidation). temperature dependence of 450 K annealed samples was improved when the as-deposited one compared. But the sample underwent 475 K and 500 K annealing exhibits inferior temperature dependence of spin-polarization, indicating that the over-annealed sample became microstucturally degraded.

• Bulletin of the Korean Chemical Society
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• v.8 no.4
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• pp.254-257
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• 1987

Palladium dichloro complexes catalysed the oxidation of cyclopentene by dioxygen in tetralin solvent at ambient temperature. Cyclopentanone formed mainly together with autoxidation products from both cyclopentene and tetralin. The oxidation seems to proceed by co-oxidation mechanism, where tetralin was first oxidized to its hydroperoxide which then oxidized cyclopentene to cyclopentanone. Mechanism of the other by-products formations has been discussed.