• Journal of Microbiology and Biotechnology
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• v.25 no.12
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• pp.2007-2010
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• 2015

A new chemical inhibitor against severe acute respiratory syndrome (SARS) coronavirus helicase, 7-ethyl-8-mercapto-3-methyl-3,7-dihydro-1H-purine-2,6-dione, was identified. We investigated the inhibitory effect of the compound by conducting colorimetry-based ATP hydrolysis assay and fluorescence resonance energy transfer-based double-stranded DNA unwinding assay. The compound suppressed both ATP hydrolysis and double-stranded DNA unwinding activities of helicase with IC₅₀ values of 8.66 ± 0.26 μM and 41.6 ± 2.3 μM, respectively. Moreover, we observed that the compound did not show cytotoxicity up to 80 μM concentration. Our results suggest that the compound might serve as a SARS coronavirus inhibitor.

• Korean Journal of Pharmacognosy
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• v.34 no.4 s.135
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• pp.269-273
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• 2003

The leaves of Acanthopanax sessiliflorus Seem. (Araliaceae), which is native plant to Korea, have not been studied yet on triterpene constituents. Three 3,4-seco-lupane triterpenoids (Compound I-III) were isolated from the MeOH extract of this plant using Diaion HP-20P, silica gel and ODS column chromatographes. Based on physicochemical and spectroscopic data, the chemical structures of these compounds were identified as follows ; chiisanogenin (Compound I), chiisanoside (Compound II), $22{\alpha}-hydroxychiisanoside$ (Compound III).

• Journal of Mechanical Science and Technology
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• v.14 no.10
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• pp.1104-1113
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• 2000

This paper proposes an efficient reverse engineering technique for compound surfaces using a boundary detection method. This approach consists in extracting geometric edge information using a vision system, which can be used in order to drastically reduce geometric errors in the vicinity of compound surface boundaries. Through the image-processing technique and the interpolation process, boundaries are reconstructed by either analytic curves (e. g. circle, ellipse, line) or parametric curves (B-spline curve). In other regions, except boundaries, geometric data are acquired on CMM as points inspected using a touch type probe, and then they are interpolated on several surfaces using a B-spline skinning method. Finally, the boundary edge and the skinned surfaces are combined to reconstruct the final compound surface. Through simulations and experimental works, the effectiveness of the proposed method is confirmed.

• Archives of Pharmacal Research
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• v.8 no.3
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• pp.109-117
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• 1985

The interaction of salicylic acid (S. A.), salicylamide (S,M) with nucleic acid base derivatives such as 9-ethyl adenine (A), 1-cyclohexyl uracil (U), 2', 3'-benzylidine-5' trityl-cytidine (C), gaunosine-2', 3', 5'-isobutylate (G) has been spectroscopically investigated to determine the binding mechanism. NMR and IR spectra were measured in nonpolar solvents. The association constant K of the formation of complex was calculated from the IR spectra. Compounds S. A. and A form a 1:1 or 1:2 cyclic hydrogen-bonded complex depending on the sample concentration. Compounds S. A. and U form a 1:1 or 1:2 hydrogen-bonded complex on the sample concentration. Compounds S. A. and C form a 2:1 hydrogen-bonded complex at low concentration (0.0016M). Compound S. A. binds compound G, but its binding does not completely break the self-association of compound G, Compound S. M. binds compounds A. U. C. G. very weakly.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.160.2-160.2
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• 2003

When ginsenoside $R_{b1}$ and $R_{b2}$ were anaerobically incubated with human fecal microflora, these ginsenosides were metabolized to compound K. When ginsenoside $R_{g3}$ was anaerobically incubated with human fecal microflora, the ginsenoside $R_{g3}$ was metabolized it to ginsenoside $R_{h2}$. Among ginsenosides, compound K and 20(S)-ginsenoside $R_h2$ exhibited the most potent cyotoxicity against tumor cells: 50% cytotoxic concentrations of compound K in the media with and without fetal bovine serum (FBS) were 27.1 - 31.6 mM and0.1 - 0.6 mM, and those of 20(S)-ginsenoside $R_h2$ were 37.5 $\rightarrow$ 50 and 0.7 - 7.1 mM mM, respectively. (omitted)

• Journal of the Korean Society for Heat Treatment
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• v.14 no.2
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• pp.103-109
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• 2001

Plasma nitrocarburising and post oxidation were performed on SM45C steel using a plasma nitriding unit. Nitrocarburising was carried out with various methane gas compositions with 4 torr gas pressure at $570^{\circ}C$ for 3 hours and post oxidation was carried out with 100% oxygen gas atmosphere with 4 torr at different temperatures for various times. It was found that the compound layer produced by plasma nitrocarburising consisted of predominantly ${\varepsilon}-Fe_{2-3}(N,C)$ and a small proportion of ${\gamma}-Fe_4(N,C)$. With increasing methane content in the gas mixture, ${\varepsilon}$ phase compound layer was favoured. In addition, when the methane content was further increased, cementite was observed in the compound layer. The very thin oxide layer on top of the compound layer was obtained by post oxidation. The formation of Oxide phase was initially started from the magnetite($Fe_3O_4$) and with increasing oxidation time, the oxide phase was increased. With increasing oxidation temperature, oxide phase was increased. However the oxide layer was split from the compound layer at high temperature. Corrosion resistance was slightly influenced by oxidation times and temperatures.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1418-1419
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• 2011

차세대 전력 반도체인 고전압 GaN 쇼트키 장벽 다이오드의 역방향 특성을 개선하기 위해서 열 산화공정이 제안되었다. AlGaN/GaN 에피탁시 위에 쇼트키 장벽 다이오드 구조가 제작되었으며, 쇼트키 컨택은 증착 후 $450^{\circ}C$에서 산화되었다. 열 산화공정이 메사 측벽의 AlGaN 및 GaN 표면에 $AlO_x$ 및 $GaO_x$를 형성하여 표면으로 흐르는 누설전류를 억제한다. 표면 및 GaN 버퍼를 통한 누설전류는 열 산화 공정 이후 100 ${\mu}m$-너비당 51.3 nA에서 24.9 pA로 1/2000 배 수준으로 감소하였다. 표면 산화물 형성으로 인하여 생성된 Ga-vacancy와 Al-vacancy는 acceptor로 동작하여 surface band bending을 증가시켜 쇼트키 장벽 높이를 증가시킨다. 애노드-캐소드 간격이 5 ${\mu}m$인 제작된 소자는 0.99 eV의 높은 쇼트키 장벽 높이를 획득하여, -100 V에서 0.002 A/$cm^2$의 낮은 누설전류를 확보하였다. 애노드-캐소드 간격이 5에서 10, 20, 50 ${\mu}m$로 증가되면 소자의 항복전압은 348 V에서 396, 606, 941 V로 증가되었다. 열 산화공정은 전력용 GaN 전자소자의 누설전류감소와 항복전압 증가를 위한 후처리 공정으로 적합하다.

• Journal of The Korean Society of Grassland and Forage Science
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• v.8 no.2
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• pp.99-103
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• 1988

With a purpose of finding out the effects of magnesium and boron enriched organic-compound fertilizer application on qualities of grasses on the hilly pasture, a field experiment was arranged with five different treatments as a randomized block design and lasted from September, 1984 to the end of growing season in 1986. The results obtained are summarized as follows: 1. Mean chemical components except NFE of grasses at the plots with organic-compound fertilizer application were appeared to contain slightly high comparing to single dressing. 2. Production of DCP with organic-compound fertilizer (1,170.2 kg/ha) was significanty increased by 20% comparing to single dressing (975.7 kg/ha) in the conventional fertilization level (p<0.05), but it was not significantly different between them in the low dressing level. 3. Production of energies (TDN, StE and NEL) with organic-compound fertilizer of low and conventional dressing level were appeared to increase by 10 and 13 to 15% than those of single dressing of the same levels, respectively. But it was not significant difference. 4. Like single dressing nutrient productions with organic-compound fertilizer were appeared significantly high due to increasing of dressing gradually (P<0.05-0.01) 5. Mineral contents of P and Mg at the plots with organic-compound fertilizer were a little higher, on the other hand, K, C/P and K/Ca + Mg equivalent ratio were slightly lower than those of single dressing, but the content of Ca tended to similar between them.

• Journal of the Korean Society of Costume
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• v.57 no.1 s.110
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• pp.93-104
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• 2007

This study is considered about the fabrics culture of Baekje Period by analyzing the fabrics pieces at a inner part of the It-bronze shoes found at the tomb of King Mu-ryeong in 1971 AD. The analysis methods of the fabrics pieces are a photographing of fabrics pieces surface by VMS, Digital camera(Nikon Coolpix 995) and the analysis of samples by SEM, XRD and FT-IR. It is assumed this fabrics pieces are the inner shoes, which consisted of compound woven silk at outward, some of tabby and a hemp at inward and the braids for decoration, of the gilt-bronze shoes. The features are as follows. 1. All of compound woven silk are the warp-faced compound tabby of plain fabrics and the density is various from high to low one. Compound woven silk which is attached the gilt-bronze shoes of the tomb of King Mu-ryeong weaves in high density by a thick thread. The fibers material of compound woven silk prove to be a silk by the analysis of wrap samples by SEM, XRD and FT-IR. 2. Tabby are excavated under the condition which attached on reverse side of compound woven silk. Those ran classify two types. First, the fine weaving by high density of wrap and weft. Second, the loose warp weaving with one warp and some of weft. 3. Hemp is almost ramie by SEM analysis and the density is different. Ramie which supposed to be attached Guem has the very low density. In addition to, Ramie pieces, excavated in condition and weaved finely, proved the conspicuous weaving skill in Baekje period. 4. Various kinds of braid are found and these ones classifies by fiber material and entwining way. Two types out of these are the one of silk thread, decorates the upper, middle parts of compound woven silk shoes and the other of hemp thread, decorates the lower parts.

• Nuclear Engineering and Technology
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• v.51 no.3
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• pp.755-760
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• 2019

Compound samples based on the mineral-like magnesium potassium phosphate matrix $MgKPO_4{\times}6H_2O$ were synthesized by solidification of high level waste surrogate. Phase composition and structure of synthesized samples were studied by XRD and SEM methods. Compressive strength of the compounds is $12{\pm}3MPa$. Coefficient of thermal expansion of the samples in the range $250-550^{\circ}C$ is $(11.6{\pm}0.3){\times}10^{-6}1/^{\circ}C$, and coefficient of thermal conductivity in the range $20-500^{\circ}C$ is $0.5W/(m{\times}K)$. Differential leaching rate of elements from the compound, $g/(cm^2{\times}day)$: $Mg-6.7{\times}10^{-6}$, $K-3.0{\times}10^{-4}$, $P-1.2{\times}10^{-4}$, $^{137}Cs-4.6{\times}10^{-7}$; $^{90}Sr-9.6{\times}10^{-7}$; $^{239}Pu-3.7{\times}10^{-9}$, $^{241}Am-9.6{\times}10^{-10}$. Leaching mechanism of radionuclides from the samples at the first 1-2 weeks of the leaching test is determined by dissolution ($^{137}Cs$), wash off ($^{90}Sr$) or diffusion ($^{239}Pu$ and $^{241}Am$) from the compound surface, and when the tests continue to 90-91 days - by surface layer depletion of compound. Since the composition and physico-chemical properties of the compound after irradiation with an electron beam (absorbed dose of 1 MGy) are constant the radiation resistance of compound was established.