• Journal of the Korean Vacuum Society
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• v.1 no.1
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• pp.168-175
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• 1992

The surface and interface morphology as well as the sheet resistance, and uniformity of TiSiz film are significantly improved and the lateral titanium silicide growth over the oxide spacer is minimized by the use of ion beam mixing and rapid thermal annealing in nitrogen ambient. In addition, TiSiz film formations on TiISi and TiISiOz system were also studied.

• Korean Journal of Materials Research
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• v.16 no.1
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• pp.50-57
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• 2006

Phase mixtures of Titanium boride, nitride, and carbide powder were produced by the reduction of a mixture of titanium and boron oxides with carbon via a gas-solid phase reaction. Boron oxides produce a vapour phase or decompose to a metal sub-oxide gaseous species when reduced at elevated temperature. The mechanism of BO sub-oxide gas formation from $B_2O_3$ and its subsequent reduction to titanium diboride for the production of uniform size hexagonal platelets is explained. These gaseous phases are critical for the formation of boride, nitride and carbide ceramics. For the production of ceramic phase composite microstructures, the nitrogen partial pressure was the most critical factor. Some calculated equilibrium phase fields has been verified experimentally. The theoretical approach therefore identifies conditions for the formation of phase mixtures. The thermodynamic and kinetic factors that govern the phase constituents are also discussed.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.40 no.9
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• pp.908-912
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• 1991

YBaCuO oxide superconductor-shows superconductive at Liquid Nitrogen temperature-must be preparate wire or thin film form for utility. The wiring is possible with heat treatment after appropriate mixture of polymeric binder and YBaCuO oxide superconductor has fabricated. This study, analyzed the characteristics of fabricated superconductor and extruded wire after application to each of a mixed at different rate in the superconductor and compared with an original pure sample. From the result, we knew that the binder component influences superconducting characteristics. The best condition for superconductivity occurred at a criticla temperature of 86.4K (8:2 rate) and at a critical current density of 100.27A/cmy with a binder packing ratio of about 20~25 percent.

• Corrosion Science and Technology
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• v.12 no.3
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• pp.119-124
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• 2013

Nano-multilayered, crystalline AlTiSiN thin films were deposited on WC-TiC-Co substrates by the cathodic arc plasma deposition. The deposited film consisted of wurtzite-type AlN, NaCl-type TiN, and tetragonal $Ti_2N$ phases. Their oxidation characteristics were studied at 800 and $900^{\circ}C$ for up to 20 h in air. The WC-TiC-Co oxidized fast with large weight gains. By contrast, the AlTiSiN film displayed superior oxidation resistance, due mainly to formation of the ${\alpha}-Al_2O_3$-rich surface oxide layer, below which an ($Al_2O_3$, $TiO_2$, $SiO_2$)-intermixed scale existed. Their oxidation progressed primarily by the outward diffusion of nitrogen, combined with the inward transport of oxygen that gradually reacted with Al, Ti, and Si in the film.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.959-960
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• 2006

Li reacts with $N_2$ at room temperature. In order to activate Li, the mechanical milling of Li with stable metal oxide, namely, $Al_2O_3$ and MgO, using a high energy vibrating ball mill was performed. In the case of Li-MgO system, it reacts with $N_2$, but hardly reacts with $O_2$. The reaction with $N_2$ generally produces $Li_3N$, while for some vigorous reactions the $Mg_3N_2$ is produced as the major phases. In the case of $Li-Al_2O_3$ system, reactivities with both $N_2$ and $O_2$ are high. The difference is explained in terms of the reaction mechanism and the Li state.

• Environmental Engineering Research
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• v.22 no.2
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• pp.224-229
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• 2017

Zinc oxide nanoparticles (ZnO NPs) have been used as additives in a variety of consumer products. While these particles may enter the environment, only a limited number of studies have investigated the effects of ZnO NPs on soil exoenzymes. Here, we investigate the long-term effects of ZnO NPs at concentrations of 50 and 500 mg/kg on the activities of six soil exoenzymes in planted soils: Dehydrogenase, fluorescein diacetate (FDA) hydrolase, urease, acid phosphatase, arylsulfatase, and ${\beta}-glucosidase$. Significant effects were observed at one or more time points for all enzymes except for FDA hydrolase. These effects included both decreases and increases in enzyme activity. Our results suggest that ZnO NP treatments of 50 and 500 mg/kg can adversely affect soil enzymes, particularly acid phosphatase and urease, and thus, these data may have implications for phosphorous and nitrogen cycles in the soil.

• Journal of the Korean Chemical Society
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• v.18 no.5
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• pp.341-353
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• 1974

The electrochemical reduction of triphenylphosphine penylimide in nonaqueous media has been examined by polarography, cyclic voltammetry, controlled-potential coulometry and electron spin resonance spectroscopy. The reduction of triphenylphosphine phenylimide proceeds by a one-electron transfer to form anion radical which undergoes both protonation and a second one-electron reduction followed by cleavage of the phosphorus-nitrogen double bond. Aniline is a major product. The cleavage of a phosphorus-phenyl bond was also observed after reduction of triphenylphosphine oxide which is one of the major products of the chemical reaction which follow the primary process.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.430-433
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• 1999

MPPO(Modified-Polyphenylene Oxide) was irradiated with helium, nitrogen, and argon ions at the ion energy of 50 keV and 70 keV from the dose region of 5$\times$10$^{15}$ to 5$\times$10$^{16}$ ions/$\textrm{cm}^2$. The resistance of the irradiated MPPO surface could be decresed about 10$^{10}$ to 10$^{7}$ $\Omega$/sq with increasing the total ion dose and ion energy. Chemical characteristics of the irradiated surface were analyzed by XPS(X-ray photoelectron spectroscopy).

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.193.2-193.2
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• 2003

Phytochemical examination of Sophorae Fructus yielded six phenolic compounds. The structures were elucidated as genistein(1), genistin(2) and genistein 7-O-${\alpha}$- L-rhamnopyranoside(3) by phytochemical and spectral evidences. The other compounds(4, 5, 6) are understudied by 2D-NMR. Nitric Oxide and PGE$_2$ production inhibitory activities in INF-${\gamma}$, LPS stimulated RAW 264.7 cell were examined. Compound 2 and 4 showed significant nitrogen monoxide(NO) production inhibitory activity in IFN-${\gamma}$, LPS stimulated RAW 264.7 cell. (omitted)

• The Journal of Korea Robotics Society
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• v.17 no.1
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• pp.93-101
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• 2022

Bioheavy oil, which is expanding its range of use as an alternative fuel to reduce environmental pollutant emissions, has a lot of difficulty in combustion due to its low emission of pollutants such as nitrogen oxide (NOx) and sulfur oxide (SOx), while its low dissipation and high oxygen content in fuel. many studies have been conducted on change in characteristics by mixing rate combustion characteristics and combustion reactions, but there have been no specific and effective studies on the composition of control system, optimization of control, development of logic for mixing and burning, minimizing environmental pollutantants discharge. In this study, we intend to consider systemmatic and empirical considerations on the composition, logic development, solve the problem of manual switching of bioler master due to excessive oxygen content and tuning of the control system for optimal combustion of bioheavy oil.