• Journal of the Korean Chemical Society
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• v.46 no.6
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• pp.523-527
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• 2002

Partition coefficient related composition of LPG are studied. Analysed sulfur compounds are ethyl mer-captan,n-propyl mercaptan and n-butyl mercaptan. The composition of liquid phase and gas phase in LPG are deter-mined by gas chromatography. The partition coefficient to related the boiling point of sulfur compounds, the temperature and the compositions of solvents, determined by using MLR(multiple linear regression) of SAS is follows; Kpc= $0.61222({\pm}0.6578)-0.04670({\pm}0.000959)Bp+0.26984(\pm0.06504)C4+0.003803(^{\circ}ae0.0019993)Tk,$ N=24, F=14.851, $R^2_{adj}$=0.6437. The boiling points of sulfur compounds at atmospheric pressure and the compositions of LPG effect mostly on partition coefficients. It is presumed that the gas odor elevating effects should be increased, where being on high tem-perature and larger amounts of n-butane.

• Korean journal of applied entomology
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• v.39 no.2
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• pp.105-110
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• 2000

Sex pheromone composition was analyzed for Dichocrocis punctiferalis, which attacksapple, peach, chestnut fruits, etc., and its behavioral and field trapping studies were conducted to developa monitoring system with its sex pheromone. Virgin females showed maximum mating behavior andhairpencil extrusion behavior between 4-5 hrs after lights-off under 16L18D photoperiod and 26rf 1 "C.During this period, two sex pheromone components, ElO-hexadecenal and ZlO-hexadecenal, weredetected by GC analysis in the hexane extract of abdominal tips of virgin females. The best attraction ofmales to various synthetic sex pheromone blends was obtained at the 70 : 30 ratio of ElO-hexadecenal andZ10-hexadecenal for hair pencil extrusion and at the 80 : 20 ratio for flying upwind response. The highestattractiveness in fields was obtained between 70 : 30 and 80 : 20 from several tests in apple, peach andchestnut orchards.and chestnut orchards.

• Applied Chemistry for Engineering
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• v.19 no.6
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• pp.617-623
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• 2008

GTL (gas-to-liquid) fuel produced by the Fischer-Tropsch reaction of carbon monoxide (CO) and hydrogen ($H_2$) is expected to be one of the environmental friendly biomass based alternatives and blended to petrodiesel. In this study, the characteristic of the fuel was analyzed by its concentration differences after blending petrodiesel in domestic market with different amounts of GTL fuel which produced from Shell. Gas chromatography shows that GTL fuel consists of longer paraffin chain than common diesel. GTL fuel showed a high flash point, distillation, kinematic viscosity, and derived cetane number. In addition, GTL fuel showed lower lubricity due to low sulfur content.

• Journal of the Korean Wood Science and Technology
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• v.33 no.6 s.134
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• pp.71-78
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• 2005

For the utilization of chestnut inner bark as forest biomass, this studies have been carried out cleary investigated about phenolic compounds from the diethyl ether solubles and ethyl acetate solubles of hot water extract from chestnut inner bark. 3 compound were isolated and their structures were identified by spectroscopic methods. They were known compounds, 3,5-dihydroxybenzoic acid, 3,4,5-trihydrixybenzoic acid and catechin. Electron donating ability (EDA) of 3 compounds were investigated. Gallic acid and catechin were found to higher EDA than control, ascorbic acid and $\alpha$-tocopherol in 10 ppm, and especially gallic acid has very higher EDA, 21 times than ascorbic acid. This gallic acid of chemical structure were substituted with free phenolic hydroxyl groups at meta and para position. It was supposed that phenolic hydroxyl groups in chemical structure was a EDA factor.

• Journal of the Korean Wood Science and Technology
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• v.39 no.1
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• pp.104-112
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• 2011

There have been few reports on the constituents and biological activity of stem bark of $Acer$ $tegmentosum$, and no phytochemical and biological studies have been reported for stem wood of $A.$ $tegmentosum$. Two flavan 3-ols (1 and 2), three phenolic acid/alcohols (3~5), and two coumarins (6 and 7) were isolated from the stem wood of $A.$ $tegmentosum$ by repeated column chromatography. The structure of isolated compounds were identified as (+)-catechin (1), (-)-epicatechin (2), $p$-hydroxybenzaldehyde (3), syringic alcohol (4), $p$-tyrosol (5), scopoletin (6), and cleomiscosin A (7) on the basis of spectroscopic evidences such as $^1H$-NMR, $^{13}C$-NMR, 2D-NMR and MS spectrum. $p$-Hydroxybenzaldehyde (3), syringic alcohol (4), scopoletin (6), and cleomiscosin A (7) have not been reported from this plant so far. (+)-Catechin (1) and (-)-epicatechin (2) showed the higher 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity than butylated hydroxyanisole (BHA) used as a positive control.

• Journal of the Korean Institute of Gas
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• v.23 no.6
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• pp.25-32
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• 2019

In many mass-consumption gas facilities, natural gas is not supplied through the pipeline of the gas corporation. LNG is supplied from the gas corporation through the tank lorry to be vaporized. In order to prevent human or property damage due to gas leakage at these facilities, a study was conducted to analyze the concentration of odorant injected at the initial and consumption points. An analysis was performed to confirm the change in odorant concentration according to the pipe position in the gas facility when a constant flow rate flowed. For this study the gas samples were taken with aluminium cylinders(4.5 L) which were created a vacuum at the pressure regulator in which the odorants was injected and the points using the gas. Odorant levels of the samples were analyzed by Gas chromatography(Main Body : Agilent 7890A, Detector : ANTEC 7090).We suggest that the small facilities using LNG need to make the management system by the types of facilities for maintaining the odorization system.

• Biomedical Science Letters
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• v.3 no.2
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• pp.115-123
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• 1997

$\alpha$-Fetoprotein (AFP) has been a useful marker in screening and/or monitoring patients with hepatocellular carcinoma, gonadal germ cell tumor, gastric carcinoma and neural tube defects. In the present study, it was attempted to produce anti-human AFP polyclonal antibodies and to develop a competitive enzyme-linked immunosorbent assay (ELISA) for the measurement of AFP in human plasma and amniotic fluid. AFP was isolated from amniotic fluid using an isolation procedure consisting of affinity chromatography and preparative polyacrylamide gel electrophoresis. The antibody directed against AFP was raised in rabbits. Double immunodiffusion and Western blotting methods showed that the antiserum was highly specific, reacting with only AFP-containing samples. Standard curve was obtained by using purified AFP and specific antiserum. The assay sensitivity was 5ng/ml and the working range was 5~l,000ng/ml. The within-assay and between-assay coefficient of variance (CV) was 4.5% and 8.5%, respectively. These results indicate that the assay is valuable for the measurement of AFP and found to be simple, reproducible, and accurate.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.5
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• pp.570-575
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• 1993

Antioxidative characteristics of melanoidin related products(MRPs) fractionated from fermented soybean sauce were studied during the oxidation process of model systems. MRPs were prepared from soybean sauce fermented for 6 months after inoculation Aspergillus oryzae by the fractionation through the Sephadex G-10 column and the freeze drying of collected fractions. MRPs inhibited the formation of peroxides during the oxidation of linoleic acids mixture in ethanolic phosphate buffer solution at $50^{\circ}C$ with the increasing tendency by their concentration in reaction systems. MRPs had hydrogen doner properties during the reaction with ${\alpha},\;{\alpha}'-diphenyl-{\beta}-picrylhydrazyl$ and also MRPs inhibited the iron and lipoxygenase catalytic oxidation. MRPs were found to be fairly stable with no loss of antioxidative effect after storage at $50^{\circ}C$ for 15days.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.6
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• pp.602-608
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• 2014

Hydrogen energy, a field of low-carbon substitute energy, can be produced by fossile fuel reforming and electrolysis of water etc. We developed 1kW class flat type reformer for PEM Fuel Cells. The PEMFC is highly sensitive to carbon monoxide because CO has detrimental effects on the performance of the fuel cell. Thus, reformed gas supplied to Fuel cell system, which maintained CO concentration below 10ppm. After applying optimum drive condition, reformed gas was measured with gas chromatography and could find out about each experimental condition of $H_2$ and CO concentration. As a results, The 1kW class plate type hydrogen generation system's optimum condition is A/F ratio ${\alpha}=1.3$, STR temperature 1023K, S/C ratio 3, and $PrOx1{\cdot}2$ 30cc/min. It turns out that installation of PrOx 2 stage is more efficient for reducing CO concentration.

• Journal of Conservation Science
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• v.12 no.1 s.15
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• pp.15-25
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• 2003

It is well known that the salt in stoneworks impact on damage of stone by various methods. Various kind of salt is detected in high content in the black surface layer of stone monuments and it is required about origin and roles of salts on blackening to considerate. In this study have been investigated the characteristics of salt in the black crust of sandstone and limestone which used in historical monuments in Berlin, Germany. Salt was analyzed for cation by Atomic Absorption and Atomic Emission Spectroscopy and for anion by ion Chromatograph. The representative ions are $Ca^{2+}\;and\;SO_4^{-2}$ in all samples and the most obvious combinations was proved in calcium sulfate by statistical methods. Because gypsum was detected by X-ray diffraction analyses in the black crusts, this calcium sulfate was confirmed by 2 hydrate type. The probable origin of Ca is air particle in atmosphere around sandstone and calcite in mother rock in limestone, and that of S is polluted air and mortar which used as conservation works.