• 한국세라믹학회지
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• 제25권1호
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• pp.1-6
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• 1988

The IR edge absorption of the important pure components of ZrF4-based glasses, including two previously uncharacterized components(ZrF4 and AlF3), has been measured. Values of the glass IR edge absorption coefficients have been calculated from these results, assuming additivity, and are compared with experimental glass absorption coefficients. The calculated ${\alpha}$ values are about a factor of two lower than the experimental values for ZrF4-based glasses, and the ZrF4 makes the largest contribution to the calculated ${\alpha}$ value.

• 한국환경과학회지
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• 제18권1호
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• pp.61-72
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• 2009

Fabrication and oxidants production of 3 or 4 components metal oxide electrode, which is known to be so effective to destruct non-biodegradable organics in wastewater, were studied. Five electrode materials (Ru as main component and Pt, Sn, Sb and Gd as minor components) were used for the 3 or 4 components electrode. The metal oxide electrode was prepared by coating the electrode material on the surface of the titanium mesh and then thermal oxidation at $500^{\circ}C$ for 1h. The removed RhB per 2 min and unit W of 3 components electrode was in the order: Ru:Sn:Sb=9:1:1 > Ru:Pt:Gd=5:5:1 > Ru:Sn=9:1 > Ru:Sn:Gd=9:1:1 > Ru:Sb:Gd=9:1:1. Although RhB decolorization of Ru:Sn:Sb:Gd electrode was the highest among the 4 components electrode, the RhB decolorization and oxidants formation of the Ru:Sn:Sb=9:1:1 electrode was higher than that of the 3 and 4 components electrode. Electrogenerated oxidants (free Cl and $ClO_2$) of chlorine type in 3 and 4 components electrode were higher than other oxidants such as $H_2O_2\;and\;O_3$. It was assumed that electrode with high RhB decolorization showed high oxidant generation and COD removal efficiency. OH radical which is electrogenerated by the direct electrolysis was not generated the entire 3 and 4 components electrode, therefore main mechanism of RhB degradation by metal oxide electrode based Ru was considered indirect electrolysis using electrogenerated oxidants.

• 한국식품영양학회지
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• 제11권5호
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• pp.493-498
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• 1998

An attempt was in this to analyzer volatile flavor components of sancho(Zanthoxylum schinfolium). Essential oils in sancho tree and fruit isolated by a simulataneous steam distillation (SDE) methods using n-pentane/diethyl ether as solvent. A total of 57 and 44 components were identified by gas chromatography(GC) and combined gas chromatography spectrometry (GC-MS), respectively. Granyl acetate(29.23%) geraniol (6.80%, p-isopropyl-2-chclohexenone(5.53%), phellandral (4.10%) in sancho fruit and 4, 6, 6-trimethyl-bicyclo(7.47%), T-carvelo(4.60%, ${\alpha}$-cypernone(3.58%) in sancho tree were found to be major volatile flavor. 22 compnents including myrcene, limonene, 1, 8-cinol in sancho fruit and 10 components including 4-(1-methylethyl)-cyclohexanol, methyl undecyl ketone in sancho tree were identified. The contents of unsaturated fatty acids of palmitic acid(24.34%), myristic acid(3,68%) in sancho tree was higher than that of the sancho fruit.

• Archives of Pharmacal Research
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• 제19권4호
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• pp.326-334
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• 1996

We investigated the optimum conditions for conversion of water-insoluble components of basidiocarps of Ganoderma lucidum to water-soluble components by hydrolyzing with chitinase. We also tried it with Ganoderma luciclum residue remaining after extracting hot water-soluble components of Ganoderma lucidum. After hydrolyzing under optimum conditions (20 ppm chitinase, 2% Ganoderma lucidum or 6% Ganoderma lucidum residue, at pH 3 and at $ 35^{\circ}C$), the contents of total water-soluble components (polysaccharide or protein) were measured, and it was found that the contents of water-soluble components increased to 1.5-2.7 fold. Michaelis constant, $K_m$ and maximum rate, $V_max$ calculated by Lineweaver-Burk plot for hydrolysis of Ganoderma lucidum were 1.75% and 0.02%/min respectively and those for hydrolysis of Ganoderma lucidum residue were 53.15% and 0.53%/min respectively The protein-bound polysaccharide was isolated after hydrolysis and molecular weights were measured by Sepharose CL-4B gel filtration and compared with the molecular weights of polysaccharide before hydrolysis.

• 한국자동차공학회논문집
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• 제12권2호
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• pp.182-189
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• 2004

The application of adhesively bonded components is increasing in various industries such as automobile, aircraft, IC packages, and soldering techniques. In spite of such wide application in adhesively bonded components, nondestructive test techniques applying to adhesively bonded components have not been clearly established yet. In this paper, characteristics of ultrasonic test on interfaces of adhesively bonded components have been investigated by calculating transmission coefficient theoretically and experimentally. From the experimental results, the optimum conditions to establish frequencies for adhesively bonded homogeneous and dissimilar components are 4∼6 MHz and 2∼4 MHz, respectively.

• ETRI Journal
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• 제28권4호
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• pp.525-528
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• 2006

In this letter, we present a design of a single chip video decoder called advanced mobile video ASIC (A-MoVa) for mobile multimedia applications. This chip uses a mixed hardware/software architecture to improve both its performance and its flexibility. We designed the chip using a partition between the hardware and software blocks, and developed the architecture of an H.264 decoder based on the system-on-a-chip (SoC) platform. This chip contains 290,000 logic gates, 670,000 memory gates, and its size is $7.5\;mm{\times}7.5\;mm$ (using 0.25 micron 4-layers metal CMOS technology).

• JSTS:Journal of Semiconductor Technology and Science
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• 제6권2호
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• pp.114-118
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• 2006

In this paper, the effect of base and collector structures on DC, small signal characteristics of SiGe HBTs fabricated by RPCVD was investigated. The structure of SiGe HBTs was designed into four types as follows: SiGe HBT structures which are standard, apply extrinsic-base SEG selective epitaxial growth (SEG), apply selective collector implantation (SCI), and apply both extrinsic-base SEG and SCI. We verified the devices could be applied to the fabrication of RFIC chip through a fully integrated 2.4 GHz down-conversion mixer.

• 한국식품영양학회지
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• 제10권1호
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• pp.25-30
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• 1997

Purge와 trap headspace sampler를 사용하여 녹차의 휘발성 성분을 추출, 확인한 후 성분조성을 동시증류추출장치로 추출된 성분가 비교하였다. Headspace법으로는 88개 성분을 확인하였으며 methyl butanal(3.1%), 1-penten-3-ol(5.48%), 2-penten-1-ol(2.89%), hexanal(5.77%), heptanal(2.24%) 등의 비교적 비점이 낮은 성분들과 2,4-heptadienal(4.28%), linalool(2.27%), nonanal(2.06%), 2,6-dimethyl cyclohexanol(2.57%) 및 $\alpha$-pinene(1.52%), caryophyllene(1.70%) 등의 hydrocarbon 화합물, $\beta$-cyclocitral(2.0%), $\alpha$-ionone(2.62%), $\beta$-ionone(2.98%) 같은 carbonyl 화합물이 주요 휘발성 성분으로 확인되었다. SDE법으로는 64개의 성분을 확인하였으며 저비점 성분들보다는 benzyl alcohol(3.79%), linalool(9.52%), terpineol(2.16%), geraniol(2.75%), nerolidol(6.50%) 등의 alcohol 성분들과 $\alpha$-ionone(1.77%), $\beta$-ionone(4.80%), geranyl acetone(1.82%) 등의 ketone 화합물, hexanoic acid(1.45%), nonanoic acid(1.11%) 등의 acid 화합물이 주요 성분으로 확인되었다.

• 한국환경과학회지
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• 제13권12호
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• pp.1067-1078
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• 2004

Atmospheric particulate matters were collected by 8-stage non viable cascade impactor from October 2002 to August at Jeju City. Eight water-soluble ionic components $(Na^+,\;NH_{4}_{+},\;K^+,\;Ca{2+},\;Mg^{2+},\;CI^-,\;NO_{3}^-\;and\;SO_{4}^{2-})$ were analyzed by Ion Chromatography. The concentration of particulate matters and eight water-soluble ionic components were determined to investigate their size distributions. Particulate matters exhibited a tri-modal distribution with peak value around $0.9,\;4.0{\mu}m\;and\;9.5{\mu}m.$ In summer, the last peak value was lower than other season values likely due to particulate matter scavenged by rain water. Four ionic components $(Na^+,\;Ca^{2+},\;Mg^{2+}\;and\;CI^-)$ exhibited a bi-modal distribution in the coarse mode whereas three ionic components $(NH_{4}^+,\;K^+\;and\;SO_{4}^{2-})$ in the fine mode, with maximum peak value around $0.9{\mu}m.\;NO_{3}^-$ was found in both the coarse and the fine mode. The enrichment factor (E.F.) of each ionic components was calculated. Based upon E.F., it is considered that $Na^+,\;CI^-,\;and\;K^+$ in coarse paricle mode were delivered form oceanic source, but other components might have other source origins.

• Applied Biological Chemistry
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• 제35권4호
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• pp.248-253
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• 1992

재래식 메주와 개량식 메주로 각각 담아 숙성시킨 된장의 향기성분을 연속 수증기증류 추출장치로 추출하여 상압에서 농축한 후, preparative GC로 GC-관능검사를 하고 GC/MC 분석과 Kovats retention index를 비교하여 동정하였다. 재래식 메주로 담은 된장의 향기성분으로는 alcohol류 11종, aldehyde류 4종, pyrazine류 2종, acid류 4종, furan류 3종, phenol류 3종, ester류 3종, hydrocarbon류 3종, ketone류 1종, 기타 성분 5종 등 39가지의 성분을 동정하였다. 개량식 메주로 담은 된장의 향기성분으로는 alcohol류 4종, aldehyde류 2종, pyrazine류 2종, acid류 2종, furan류 1종, ester류 2종, hydrocarbon류 1종, ketone류 2종, 함황 화합물 1종, 기타 성분 4종 등 21가지의 성분을 동정하였다. 한편, 재래식 메주로 담은 된장과 개량식 메주로 담은 된장에서 함께 동정된 향기성분으로는 3-methyl-1-butanol, 4-methyl-3-heptanol, trimethyl-pyrazine, 1-octen-3-ol, 2-furancarboxaldehyde, tetramethyl-pyrazine, benzaldehyde, 3-methyl-butanoic acid, naphthalene, 2-ethyl-3-methyl-oxetane 등 10가지 성분이었다.