• Journal of the Korean institute of surface engineering
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• v.29 no.5
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• pp.519-524
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• 1996

We synthesized semiconducting Sn-doped diamondlike carbon films by rf plasma-enhanced chemical vapor deposition using an organotin compound as a dopung gas source. XPS quan-titative analysis for the deposited films after 60 s argon ion etching revealed that Sn concen-tration increased with the partial pressure of the organotin compound in the reactant gas. In C 1s spectra, there was a component due to C-Su bond which had a negative chemical shift. C 1s spectra also indicated that the deposited films were relatively $sp^2$ rich. The chemical shift of the Sn-C bond in Sn $3d_{5/2}$ spectra was about +1.7 eV. The electrical resistivity and the optical transmittance were also investigated.

• Korean Journal of Materials Research
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• v.14 no.4
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• pp.265-269
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• 2004

Plasma nitrocarburising and post oxidation were performed on SCM435 steel by a pulsed plasma ion nitriding system. Plasma oxidation resulted in the formation of a very thin ferritic oxide layer 1-2 $\mu\textrm{m}$ thick on top of a 15～25 $\mu\textrm{m}$ $\varepsilon$-F $e_{2-3}$(N,C) nitrocarburized compound layer. The growth rate of oxide layer increased with the treatment temperature and time. However, the oxide layer was easily spalled from the compound layer either for both oxidation temperatures above $450^{\circ}C$, or for oxidation time more than 2 hrs at oxidation temperature $400^{\circ}C$. It was confirmed that the relative amount of $Fe_2$$O_3$, compared with $e_3$$O_4$, increased rapidly with the oxidation temperature. The amounts of ${\gamma}$'-$Fe_4$(N,C) and $\theta$-$Fe_3$C, generated from dissociation from $\varepsilon$-$Fe_{2-3}$ /(N,C) phase during $O_2$ plasma sputtering, were also increased with the oxidation temperature.e.

• Bulletin of the Korean Chemical Society
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• v.35 no.4
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• pp.989-993
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• 2014

The molecular structures of 2,6-diaza-1,3,5,7-tetraoxaspiro[3,3]heptane (1) and its dinitro derivative, 2,6-dinitro-2,6-diaza-1,3,5,7-tetraoxaspiro[3,3]heptane (2), were fully optimized without symmetry constraints at $HF/6-31G^*$ level of theory. A bisected conformation with respect to the ring is preferred with a $C_2$ symmetric structure. The density of each molecule in the crystalline state was estimated to 1.12 and 2.36 $g/cm^3$ using PM3/VSTO-3G calculations from the molecular volume. The heat of formation was calculated for two compounds at the CBS-4M level of theory. The detonation parameters were computed using the EXPLO5 software: D = 6282 m/s, $P_{C-J}$ = 127 kbar for compound 1, D = 7871 m/s, $P_{C-J}$ = 307 kbar for compound 2, and D = 6975 m/s, $P_{C-J}$ = 170 kbar for 60% compound 2 with 40% TNT. Specific impulse of compound 1 in aluminized formulation when used as monopropellants was very similar to that of the conventional ammonium perchlorate in the same formulation of aluminum.

• Korean Journal of Materials Research
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• v.19 no.4
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• pp.207-211
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• 2009

In this study, we attempted to develop a convenient aluminizing process, using Al-Ti mixed slurry as an aluminum source, to control the Al content of the aluminized layer as a result of a one-step process and can be widely adopted for coating complex-shaped components. The aluminizing process was carried out by the heat treatment on disc and rod shaped S45C steel substrates with Al-Ti mixed slurries that were composed of various mixed ratios (wt%) of Al and Ti powders. The surface of the resultant aluminized layer was relatively smooth with no obvious cracks. The aluminized layers mainly contain an Fe-Al compound as the bulk phase. However, the Al concentration and the thickness of the aluminized layer gradually decrease as the Ti proportion among Al-Ti mixed slurries increases. It has also been shown that the Al-Ti compound layer, which formed on the substrate during heat treatment, easily separates from the substrate. In addition, the incorporation of Ti into the substrate surface during heat treatment was not observed.

• Food Science and Biotechnology
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• v.15 no.3
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• pp.363-368
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• 2006

Twenty-four different natural food materials extracted with 80% methanol were used to investigate the inhibition of cell-mediated immediate type allergic reactions induced by compound 48/80 in rat peritoneal mast cells (RPMCs). Nine 80% methanol extracts screened at a concentration of $10\;{\mu}g/mL$ inhibited histamine release from RPMCs induced by compound 48/80. Of these, two materials (Ulmus parvifolia and Liriope platyphylla Wang et Tang) were extracted and fractionated into four different solvent types (chloroform, ethylacetate, butanol, and water), and the fractions with major anti-allergic effects were assessed. The chloroform fraction of U. parvifolia (UP) at $5\;{\mu}g/mL$ and the ethylacetate fraction of L. platyphylla Wang et Tang (LPWT) at $1\;{\mu}g/mL$ showed the greatest inhibition of histamine release induced by compound 48/80. The chloroform fraction of UP and the ethylacetate fraction of LPWT in combination showed a greater inhibition of histamine release than either fraction alone. The cAMP levels in RPMCs treated with UP and LPWT were significantly greater than in cells treated with compound 48/80 alone. Our studies suggest that extracts from UP and LPWT may alleviate immediate type hypersensitivity reactions through the increase of cAMP levels in the mast cells.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.9
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• pp.127-135
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• 2017

Ginseng, whichhas long been used for its medicinal properties, has recently been investigated by scientific research to identify its components and evaluate its efficacy. Recently, two components of ginseng, Rg3 and compound K, have been attracting attention and various functional materials containing these materials have been developed and investigated. In this study, compound K wasproduced using yeast (Saccharomyces servazzii, GB-07) and To be used for industrialization. The antioxidant and anti-inflammatory activity of compound K (containing 20 g/g) ginseng fermented extract was investigated. In the fermented ginseng extract, the free radical DPPH was scavenged in a concentration-dependent manner and the production of ROS was inhibited in macrophages(RAW 264.7 cell). Moreover, the LPS-induced inflammatory cytokines $IL-1{\beta}$, IL-6 and $TNF-{\alpha}$ were suppressed. These results suggest the possibility of industrialization viathe development of products containing compound K through future process development and various efficacy tests.

• Proceedings of the Materials Research Society of Korea Conference
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• 2008.11a
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• pp.34.2-34.2
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• 2008

• Proceedings of the Materials Research Society of Korea Conference
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• 2002.05a
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• pp.155-155
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• 2002

• Proceedings of the Materials Research Society of Korea Conference
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• 1994.11a
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• pp.63-63
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• 1994

• Proceedings of the Materials Research Society of Korea Conference
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• 1994.11a
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• pp.144-145
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• 1994