• Food Science and Biotechnology
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• 제17권4호
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• pp.805-808
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• 2008

Ginsenosides are responsible for the pharmacological and biological activities of ginseng. In this study, ginsenoside Rh1 and compound K were isolated and purified from fermented ginseng substrate and their anti-allergic effects were assessed in compound 48/80-induced anaphylactic shock model. The fermented ginseng substrate was extracted by methanol and ginsenoside Rh1 and compound K were efficiently purified by preparative high performance liquid chromatography (prep HPLC). Their quality and quantity were analyzed by liquid chromatography-mass spectrometer (LC-MS) and HPLC. Ginsenoside Rh1 showed better anti-allergic effects than compound K in compound 48/80-induced anaphylactic shock model. This study suggested that fermented ginseng extracts with enriched Rh1 may be utilized as a potential biomaterial of functional food for the alleviation of allergic symptoms.

• 한국표면공학회지
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• 제34권4호
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• pp.281-288
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• 2001

Phosphating treatments have been performed to improve paint adhesion and corrosion resistance of zinc and zinc alloy coated steels for a long time. In this work, the effects of the addition of chelate compound were studied to improve the stability of surface conditioning solution and properties of zinc phosphate films. The coalescence of colloidal Ti-compound and extraneous charged particles (alkaliearth metal cation such as $Mg^{2+}$ , $Ca^{2+}$ ) were suppressed by using a surface conditioning solution with chelate compound. Therefore, after surface conditioning solution containing chelate compound was left standing for one week at room temperature, the formation of a white sediment was decreased comparing to surface conditioning solution without chelate compound. The crystal size of phosphate film was fine and the whiteness value of phosphated zinc coated steel sheets was also high without the decrease of corrosion resistance and anti-patina. It was very effective to use chelate compound improving the stability of surface conditioning solution.

• East Asian mathematical journal
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• 제39권3호
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• pp.331-347
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• 2023

We present an identity on moments of a compound random variable by using an auxiliary counting random variable. Based on this identity, we develop a new recurrence formula for obtaining the raw and central moments of any order for a given compound random variable.

• 한국식품과학회지
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• 제27권1호
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• pp.124-128
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• 1995

결명자 추출물을 이용하여 발암성 니트로사민의 직접적인 생성인자인 아질산염 소거작용과 그 소거인자의 분리 및 동정을 시도하였다. 결명자의 메탄올 추출물을 chloroform, ethyl ether, ethyl acetate, 물분획 순으로 순차용매 분리한 결과 ethyl acetate획분이 가장 우수한 것으로 나타났다. Ethyl acetate획분을 silica gel column chromatography하여 얻은 compound A와 B획분 중에서 compound A는 pH 1.2에서 44.5%/200 ${\mu}g$의 아질산염 소거능을, compound B는 극히 낮은 아질산염 소거능을 나타내었다. HPLC를 이용하여 compound A획분으로 부터 compound A-1획분을 분리하고 아질산염 소거효과를 ascorbic acid와 비교하였을 때 compound A-1은 ascorbic acid에 비해 월등한 소거효과를 나타내었으며, UV, IR 및 $^1H-NMR$의 결과로부터 그 구조는 $nor-rubrofusarin-6-{\beta}-mono-D-glucoside$으로 추정하였다.

• Biomolecules & Therapeutics
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• 제5권2호
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• pp.215-221
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• 1997

In an effort to screen new selective antitumor agents from the broth of soil microorganism, cytotoxicity oriented screening was performed against tumor cells and 3 compounds (Compound 1, 2 and 3) were isolated from Sreptomyces parvullus ISP 5048 and their chemical structures were determined. Among these compounds, Compound 2 showed the highest cytotoxicity against P388Dl and L1210. While the $IC_{50}$/ values of compound 2 against P388Dl and L1210 were 0.073$\mu$g/ml and 0.07$\mu$g/ml, respectively, and the $IC_{50}$/ value of Compound 3 was 0.17$\mu$g/ml against human lung cancer cells, A549, the cytotoxicity of Compound 2 and 3 against normal cell line, Vero E6 cell was about 4- and 8-fold lower than that of adriamycin. Based on the chemical analysis data, Compound 3 was octacosamicine A, a known antibiotic, which was reported by Dobasih et al. (1988). Taken together the results demonstrated that Compound 2 and Compound 3 has the possibility to be developed as antitumor agent because of its potent cytotoxicity as well as high selectivity against various cancer cell lines.

• Tribology and Lubricants
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• 제13권1호
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• pp.42-52
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• 1997

This paper deals with wear characteristics of ion-nitrided metal theoretically and experimentally in order to analysis of wear phenomena. Wear tests show that compound layer of ion-nitrided metal reduces wear rate when the applied wear load is mall. However, as th load becomes large, the existence of compound layer tends to increase wear rate. The residual stress at the surface of ion-nitrided metal is measured, and the internal stress distribution is calculated when the normal and tangential forces are applied to the surface of metal. Compressive residual stress is largeest at the compound layer, and decreases as the depth from the surface increases. Calculation shows that the maximum stress exists at a certain depth from the surface when normal and tangential force are applied, and that the larger the wear load is the deeper the location of maximum stress becomes. In the analysis, it is found that under small applied wear load the critical depth, where voids and cracks may be created and propagated, is located at the compound layer, as the adhesive wear, where hardness is an important factor, is created the existence of compound layer reduces the amount of wear. When the load becomes large the critical depth is located below the compound layer, and delamination, which may be explained by surface deformation, crack nucleation and propagation, is created, and the existence of compound layer increases wear rate.

• Journal of Microbiology and Biotechnology
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• 제13권1호
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• pp.9-14
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• 2003

When ginsenosides Rbl, Rb2, and Rc were anaerobically incubated with commercial and human intestinal lactic acid bacteria, most commercial lactic acid bacteria did not metabolize these ginsenosides to compound K. However, lactic acid bacteria, B. minimum KK-1, Bifidobacterium cholerium KK-2, and B. cuniculi K-513, isolated from human intestinal microflora transformed these ginsensosides to compound K. When the bacterial mixtures of commercial lactic acid bacteria were incubated with these ginsenosides, these compounds were not transfformed to compound K. However, when Bzfidobacterium KK-1 and KX-2 were miked, these ginsenosides were synergistically transformed to compound K. When water extract of ginseng was incubated with these mixed bifidobacteria, compound K was potently produced. Therefore, it is suggested that, if ginseng with these mixed bifidobacteria is fermented, compound K-enforced ginseng materials could be produced that show cytotoxicity against tumor cell lines.

• Bulletin of the Korean Chemical Society
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• 제32권2호
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• pp.673-680
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• 2011

The compound 3-(2-Mercaptopyridine)phthalonitrile has been synthesized and characterized by IR, UV-vis, and X-ray single-crystal determination. The molecular geometry from X-ray determination of the title compound in the ground state has been compared using the Hartree-Fock (HF) and density functional theory (DFT) with the 6-31G(d) basis set. The calculated results show that the DFT and HF can well reproduce the structure of the title compound. The energetic behavior of the title compound in solvent media was examined using the B3LYP method with the 6-31G(d) basis set by applying the Onsager and polarizable continuum model. Using the TD-DFT and TD-HF methods, electronic absorption spectra of the title compound have been predicted and good agreement with the TD-DFT method and the experimental determination was found. The predicted nonlinear optical properties of the title compound are much greater than those of urea. Besides, molecular electrostatic potential of the title compound were investigated by theoretical calculations. The thermodynamic properties of the compound at different temperatures have been calculated and corresponding relations between the properties and temperature have also been obtained.

• 열처리공학회지
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• 제1권1호
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• pp.8-12
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• 1988

This study has been carried out to evaluate gaseous nitrocarburizing treatment undertaken for pure iron at $570^{\circ}C$ in an atmosphere containing 50% endothermic gas, generated from natural gas, and 50% ammonia. The results obtained from the experiment are as follows ; 1) The microstructure of gaseous nitrocarburized pure iron consists of the compound layer on the surface and the diffusion zone beneath it. The compound layer progresses uniformly into ferrite with a thickness of $20{\mu}$ obtained after treating for 3 hours. 2) Chemical analysis has shown that the compound layer has a C/N ratio of 0.19 and that the average combined interstitial content of the compound layer is about 30 atomic percent, which is close to the lower limit of the ${\varepsilon}$-carbonitride phase field in Fe-C-N phase diagram. 3) X-ray diffraction analysis has revealed that the compound layer consists mainly of the c.p.h. phase, ${\varepsilon}-Fe_3$(C.N) and a small amount of $Fe_4N$ and traces of ferrite are also present in the compound layer. 4) The microhardness of the compound layer is about 600 V.H.N and shows a relatively sharp fall-off at the compound layer/diffusion zome interface. 5) The average actual degree of ammonia dissociation is calculated to be 27% for a gaseous nitrocarburizing treatment carried out at $570^{\circ}C$.

• 열처리공학회지
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• 제7권3호
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• pp.206-218
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• 1994

In 50%$NH_3+Air+N_2$ atmospheres, the effect of air additions on the growth characteristics of the compound layer during oxynitriding at $570^{\circ}C$ for 2hr in carbon and alloy steels has been investigated. The ammount of apparent residual ammonia during oxynitriding has shown to be increased with air additions(9~36 Vol. %) and X-ray diffraction analysis of case oxynitreded has shown that the compound layer consist of ${\varepsilon}-Fe_{2-3}$(N, C) phase and ${\gamma}^{\prime}-Fe_4$(N,C) phase. In the case of carbon steels, the thickness of oxide layer, compound layer and porous layer and the amount of ${\varepsilon}-Fe_{2-3}$(N,C) phase in the compound layer were increased with additions of air in 50%$NH_3+N_2$ atmospheres. At the same gas composition, the thickenss of oxide layer, compound layer and porous layer in alloy steels showed slightly thin layer thickness compared to those of carbon steels and the ${\gamma}^{\prime}-Fe_4$(N,C) phase in the compound layer of alloy steels was found barely. Therefore, the most obvious effect of air addition in the gas nitriding atmosphere has been found to in crease further kinetics of nitriding reaction.