• Journal of the Korean Ceramic Society
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• v.40 no.9
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• pp.916-920
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• 2003

The change of structure and morphology in ( $U_{0.913}$G $d_{0.087}$) $O_2$ during oxidation at 475$^{\circ}C$ and heat treatment at 130$0^{\circ}C$ in air were investigated using XRD, SEM, and EPMA. The ( $U_{0.913}$G $d_{0.087}$) $O_2$ cubic phase converted to ( $U_{0.913}$G $d_{0.087}$)$_3$ $O_{8}$ orthorhombic phase by oxidation at 475$^{\circ}C$ in air. The XRD and EPMA result of the 130$0^{\circ}C$ heat treated powder revealed that ( $U_{0.913}$G $d_{0.087}$)$_3$ $O_{8}$ orthorhombic phase was separated into $U_3$ $O_{8}$ and ( $U_{0.67}$G $d_{0.33}$) $O_{2+}$x/ cubic phase. The weight variations of (U,Gd) $O_2$ with various Gd contents were measured using TGA at the same heat treated condition. The weight variation during the heat treatment of Gd dissolve (U,Gd) $O_2$ in air can be expressed in terms of phase reaction equations related with oxidation and phase separation. Based on these phase reaction, a initial content of Gd dissolved in (U,Gd) $O_2$ can be exactly calculated by measuring the weight change during the heat treatment.

• Publications of The Korean Astronomical Society
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• v.8 no.1
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• pp.119-136
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• 1993

Optimum hypering conditions are found for IIIa-J, IIIa-F, 103a-O, 103a-D, and IIa-O plates using hypersensitization machine in KAO. For every experimental plate we get speed gain, fog increment, signal to noise ratio and relative DQE according to hypering time and temperature. The hypersensitization method is baking with 8% hydrogen mixed gas. For IIIa-J, 103a-O, and 103a-D plates treated $65^{\circ}C$, 3 hours baking, the speed gains arc increased by about 10 times, 2 times, and 2 times compared to untreated plates, respectively. The fogs are increased by 0.08, 0.10, and 0.08, respectively. For IIIa-F, IIa-O plates treated $65^{\circ}C$, 2 hours baking, the speed gains are increased by about 4.7 times and 1.8 times compared to untreated plates, respectively. The fogs are increased by 0.15 and 0.04, respectively.

• Korean Journal of Pharmacognosy
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• v.30 no.3
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• pp.290-294
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• 1999

From the legumes of Albizzia julibrissin Durazzini (Leguminosae), a mixture of long-chain alcohols, ${\alpha}-spinasterol$, a mixture of acylated sterol glycosides and ${\alpha}-spinasteryl$ $3-O-{\beta}-D-glucoside$ were isolated. Two mixtures of long-chain alcohols and acylated sterol glycosides were characterized as 1-hexacosanol (major) and 1-tetracosanol, and $3-O-[6'-O-palmitoyl-{\beta}-D-glucosyl]-{\alpha}-spinasterol$ (major) and its 6'-O-stearoyl ester. All compounds were identified on the basis of spectral data and chemical reactions.

• Journal of Applied Biological Chemistry
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• v.51 no.6
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• pp.272-276
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• 2008

Purification and some properties of Xylogone sphaerospora ${\beta}$-mannanase were reprevious previous paper. Locust bean gum galactomannan was hydrolyzed by the purified ${\beta}$-mannanase, and then the hydrolysates was separated by activated carbon column chromatography. The main hydrolysates were composed of D.P. (Degree of Polymerization) 4 and 6 galactosyl mannooligosaccharides. For elucidate the structure of D.P 4 and 6 galactosyl mannooligosaccharides, sequential enzymatic action was performed. D.P 4 and 6 were identified as ${Gal^2}{Man_3}\;(6^2-mono-O-{\alpha}-D-galactopyranosyl-4-O-{\beta}-D-mannotriose)$ and ${Gal^2}{Man_5}\;(6^2-mono-O-{\alpha}-D-galacto- pyranosyl-4-O-{\beta}-D-mannopentaose)$. To investigate the effects of locust bean gum galactosyl mannooligosaccharides on in vitro growth of Bifidobacterium longum, B. bifidum, B. infantis, B. adolescentis, B. animalis, B. auglutum and B. breve. Bifidobacterium spp. were cultivated individually on the modified-MRS medium containing carbon source such as D.P. 4 and D.P. 6 galactosyl mannooligosaccharides, respectively. B. longum and B. bifidum grew up to-fold and 6.6-fold more effectively by the treatment of D.P. 6 galactosyl mannooligosaccharides, compared to those of standard MRS medium. Especially, D.P. 6 was more effective than D.P. 4 galactosyl mannooligosaccharide on the growth of Bifidobacterium spp.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• v.y2005m4
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• pp.83-87
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• 2005

In this paper, the combustion characteristics of a hybrid propulsion system were studied with various L/D(length vs diameter) ratio of the single port type solid fuel. Experiments of L/D ratio change were performed for 2 cases with the fixed grain port diameter and fuel length respectively. For the First case, results show that there are no large variation for regression rates as the L/D ratio changes. And as the L/D ratio increases, the O/F ratio and thrust tends to increase. For the Second case, there are no large change for O/F ratio and thrust as L/D ratio changes. On the other hand, as the L/D ratio decreases, only the regression rate tends to increase.

• Archives of Pharmacal Research
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• v.20 no.3
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• pp.291-296
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• 1997

The studies were carried out to evaluate the constituents in the aerial part of Isodon excisus var. coreanus (Labiatae). From the aqueous fraction of methanol extract, compound I (${\alpha}$-[[3-(3, 4-dihydroxyphenyl)-1-oxo-2-propenyl]oxy]-3,4-dihydroxy-benzenepropanoic acid), compound II (9-methyl-dihydroferulic acid-4-O-.betha.-D-glucopyranosyl $(1{\rightarrow}2)$-${\alpha}$-L- rhamnopyranosyl (1.rarw.4)-.betha.-D-glucopyranoside), compound III (ent-7.alpha., 11${\alpha}$,15.betha.-trihydroxy-kaur-16-en-1-O-.betha.-D-glucopyranoside) and compound IV ($2{\alpha}$,3${\beta}$,$7{\alpha}$,23-tetrahydroxy-olean-12 -en-28-oic acid 28-O-${\beta}$-D-glucopyranoside) were isolated and identified on the basis of their physicochemical and spectroscopic evidences[IR, FAB(-)MS,$^{1}H-NMR,$$^{13}C-NMR,$$ HMQC$$^{1}H-^{1}H $COSY and HMBC (Heteronuclear Multiple Bond Connectivity)]. Especially, New compounds II and III were named Isodonin A and Isodonin B respectively.

• Korean Journal of Materials Research
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• v.2 no.1
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• pp.76-82
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• 1992

Deposition of $TEOS-O_3$ oxide film as inter-metal dielectric layer shows the substrate dependency according to the substrate material and pattern density and pitch size. To minimize substrate and Pattern dependency, TEOS-base and $SiH_4-base$ Plasma oxide were predeposited as underlying material on the substrate. The substrate dependency of $TEOS-O_3$ oxide film was more significant on TEOS-base plasma oxide than on $SiH_4-base$ plasma oxide. The dependency of $TEOS-O_3$ oxide film was remarkably reduced, or nearly eliminated, by $N_2$plasma treatment on TEOS-base plasma oxide, which appears to be caused by the O-Si-N structure, observed on the the surface of TEOS-base plasma oxide.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1997.10a
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• pp.59-65
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• 1997

The calibration of O.M.D is carried out experimentally and is analysed theoretically. O.M.D experimentally measures the change in optical density of artificially contaminated oil which contains Fe powder of 5, 10, 20, 30, 40, 50, 70, 100, 200 ppm. The change in optical density, D$_1$ means the logarithmic transmittance of I$_0$ over $I_1 D_2$ denotes the logarithmic transmittance I$_2$ over I$_1$ on electromagnetic force which arranges the ferrous particles along the line of magnetic force. The theoretical D$_1$ which increases linearly as increasing Fe concentrations, is analysed by light attenuation theory. The difference between theoretical D$_1$ and experimental D$_1$ is due to the attenuation of micro bubbles and the agglomeration of fine particles in the sample oil. The calibrated O.M.D is applied to the sample oil from the high-powered diesel engine. Also the results are compared with those out of the off-line techniques such as JOAP and ICP.

• Journal of the Korean Chemical Society
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• v.52 no.3
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• pp.322-327
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• 2008

The geometrical structure, binding energy and vibrational frequencies of HOOCl-H2O cluster were investigated with MP2/6-311G(d,p) and MP2/6-311G(2d,2p) methods. The most stable conformer is skew HOOCl-H2O cluster and the binding energy was 46~48kJ/mol. The trans HOOCl-H2O cluster is less stable than skew form, but the binding energy is big enough to stablize the complex. The vibrational frequencies of skew and trans HOOCl-H2O cluster were calculated and compared with the spectrum of HOOCl.

• Proceedings of the Korean Magnestics Society Conference
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• 1993.11a
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• pp.36-37
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• 1993