• Fire Science and Engineering
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• v.25 no.3
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• pp.113-118
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• 2011

The flash point is an important indicator of the flammability of a chemical. The minimum flash point behaviour (MFPB) is exhibited when the flash point of a mixture is below the flash points of the individual components. The identification of this behaviour is critical, because a hazardous situation results from taking the lowest component flash point value as the mixture flash point. In this study, the flash points for the n-butanol + n-decane and n-octane + n-propanol systems which exhibit MFPB, were measured by Tag open-cup apparatus. The experimental data were compared with the alues calculated by the Raoult's law, the van Laar equation and the Wilson equation. The calculated values based on the van Laar and Wilson equations were found to be better than those based on the Raoult's law. It was concluded that the van Laar and Wilson equations were more effective than the Raoult' law at describing the activity coefficients for non-ideal solution such as the n-butanol + n-decane and n-octane + n-propanol systems. The predictive curve of the flash point prediction model based on the Wilson equation described the experimentally-derived data more effectively than was the case when the prediction model was based upon the van Laar equation.

• Journal of the Korean Society of Safety
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• v.29 no.6
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• pp.76-80
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• 2014

The flash point is one of the most important physical properties used to determine the fire hazard of flammable liquid mixture and defined as the lowest temperature at which a liquid produces sufficient vapor to form a combustible mixture with air. The main purpose of this paper is to measure and predict the flash point of binary flammable miscible mixtures. The flash points for n-hexanol+n-butyric acid and n-butanol+propionic acid, were measured by using Seta-flash closed cup method. The experimentally derived data were correlated with the binary interaction parameters of the van Laar and NRTL equations through the optimization method. The flash points estimated by these correlations were compared with those calculated by the method based on Raoult's law. The optimization method were found to be better than the method based on the Raoult's law.

• Food Science and Preservation
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• v.21 no.2
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• pp.246-253
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• 2014

The objective of this study was to investigate the antioxidative acitivities of various solvent extracts from haw (Crataegus pinnatifida Bunge) pulpy. The Freeze-dried pulpy of haw was extracted with five solvents (70% methanol, 70% ethanol, chloroform:methanol (CM, 2:1, v/v), n-butanol, and ethyl acetate or EA), and the DPPH, reducing power, ferric-reducing antioxidant power (FRAP), ABTS, NO, hydroxyl radical scavenging activity were then measured. The DPPH radical scavenging activity of the 70% methanol and 70% ethanol extracts were 92.89% and 91.17% in the 0.8 mg/mL concentrations, respectively, which were higher than those of the other extracts. The reducing power and FRAP decreased in the following order: 70% methanol, 70% ethanol, n-butanol, EA, and CM extracts. The ABTS radical scavenging activity was high in the 70% methanol and 70% ethanol extracts and low in the n-butanol extract. The NO radical scavenging activity was high in the 70% methanol and 70% ethanol extracts but low in the CM extracts. On the other hand, the hydroxyl radical scavenging activity was high in the n-butanol and 70% methanol extracts but low in the EA extract. These results suggest that the 70% methanol and 70% ethanol extracts from haw will be useful as natural antioxidant and biohealth foods.

• Journal of the Korean Society of Safety
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• v.23 no.6
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• pp.70-75
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• 2008

The values of the AIT(Autoignition temperature) for fire and explosion protection are normally the lowest reported. The minimum autoignition temperature behavior(MAITB) of flammable liquid mixtures is exhibited when the AIT of mixture is below the AIT of the individual components. The MAITB is an interesting experimental features, which can be significant from the perspective of industrial safety. In this study, the AITs of m-xylene+n-butyric acid and ethylbenzene+n-butanol systems were measured using ASTM E659-78 apparatus. The AITs of m-xylene, n-butyric acid, ethylbenzene and n-butanol which constituted two binary systems were $587^{\circ}C$, $510^{\circ}C$, $475^{\circ}C$ and $340^{\circ}C$ respectively. The m-xylene+n-butyric acid system is exhibited MAITB at 0.3 mole fraction of m-xylene, and its minimum autoignition temperature was $460^{\circ}C$.

• Journal of the Korean Applied Science and Technology
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• v.32 no.2
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• pp.312-319
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• 2015

In this study, n-butanol and ethyl acetate extracts were prepared from raw yam (Dioscorea batatas DECNE.). Their antioxidative potencies were investigated employing various in vitro methods, such as ferrous ion chelating, ${\beta}$-carotene bleaching assay, lipid peroxidation inhibition and nitric oxide (NO) radical scavenging and nitrite scavenging activity. The n-butanol fraction was assayed to possess stronger antioxidant activity by ${\beta}$-carotene bleaching assay, lipid peroxidation inhibition and NO radical scavenging activity. However, ethyl acetate extract was more effective in chelating ferrous ion and scavenging nitrite. Based on the results obtained, yam is a potential active ingredient that could be applied in antioxidation as well as bio-health functional food to take a good part in prevention of human diseases and aging.

• YAKHAK HOEJI
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• v.36 no.6
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• pp.548-555
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• 1992

The biological activities of fruits of Poncirus trifoliata have been studied. 70% Ethanol extract of Ponciri Fructus was fractionated with ether, ethyl acetate and n-butanol by turns. The ether fraction showed antibacterial activity on Staphylococcus aureus and inhibited the contractability of the isolated mice ileum. The ethyl acetate and n-butanol fractions showed the anti-edematous effect on the carrageenin-induced edema of rat hindpaw. From the n-butanol fraction, one of the flavonoid glycoside was isolated and identified as poncirin. Ponciri Fructus contained about 6% poncirin which was 5,7-dihydroxy-4´-methoxy flavanone rhamnoglucoside and poncirin showed antiinflammatory activities. Poncirin was considered as the major effective component of Ponciri Fructus.

• Journal of Food Hygiene and Safety
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• v.4 no.3
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• pp.257-261
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• 1989

In order to evaluate the characteristics and quality of various Korean alcoholic beverage, the higher alcohols profiles were analyzed by gas-chromatography. Total amount of the higher alcohols depended on the type and class of the liquors. Gaschromatographic analysis showed that the type of Gin, Rum and Vodka except for SB contain n-propanol mainly. The amount of the higher alcohols determined was proportional to the content of the originally fermented liquor in the whisky. The difference in the ratio of iso-amyl alcohol content to that of iso-butanol may be useful as a parameter in evaluating the class of the whisky.

• Journal of the Korean Society of Safety
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• v.22 no.3 s.81
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• pp.22-27
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• 2007

The knowledge of the flash point of the various liquid substances is required because of process safety and control in industrial fire protection. The epoxy resin is one of versatile resins that has wide selection of using curing agents and additives to achieve various applications such as coatings, adhesives, interior materials, reinforced plastics and electrical insulation. In this study, the lower flash points for p-xylene+epoxy resin, o-xylene+epoxy resin and n-butanol+epoxy resin systems were measured by using Pensky-Martens closed cup tester. The lower flash points for p-xylene+epoxy resin, o-xylene+epoxy resin and n-butanol+epoxy resin systems rapidly increased 80wt%, 90wt% and 95wt% of epoxy resin concentration, respectively. This results serve as a guide to estimate flash point of any epoxy resin solution.

• Korean Journal of Pharmacognosy
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• v.39 no.3
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• pp.228-232
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• 2008

Antidiabetic effects of an aqueous and solvent extract prepared from the root, stem and fruit parts of Acanthopanax senticosus, were investigated in experimental Streptozotocin (STZ)-induced diabetic rats model. The n-butanol and water extracts of A. senticosus were orally administrated once a day for 6 days. The n-butanol extracts of fruit (FB) showed highest efficiency than other groups (water extracts of stem, root and fruit; butanol extracts of stem, root) on serum glucose values in the STZ-induced diabetic rats. We have studied gene expression of glucose transporter genes in C2C12 skeletal muscle cell line during differentiation treated by the n-butanol and water extracts of A. senticosus, SW, RW, FW, SB, RB and FB. The GLUT4 gene was high expressed by FB treatment. These findings suggest that FB of A. senticosus have GLUT4 gene expression activity for glucose homeostasis and may have beneficial effects on blood glucose lowering in the diabetic patients.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.6
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• pp.677-682
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• 2006

This study was conducted to investigate the effect of garlic extracts on electron donating ability nitrite-scavenging activity and N-nitrosodimethylamine (NDMA) formation. Content of total phenolic compounds was the highest in ethyl acetate extract. Electron donating ability was significantly increased with increasing sample concentration, as $88.0{\pm}1.53%$ from ethyl acetate extract and $77.5{\pm}0.8%$ from butanol extract in concentration of 10 mg/mL. Butanol extract from garlic with highest nitrite scavenging activity and inhibition effect of NDMA formation exhibited $96.9{\pm}0.75%$ and $68.6{\pm}1.15%$ in concentration of 10 mg/mL, respectively. The butanol extract was fractionated into 5 fractions using prep-LC. Nitrite-scavenging activity and inhibition effect of NDMA formation were excellent in fraction III, which further fractioned into 3 subfractions (III-a, III-b and III-c) using prep-LC. Of the 3 subfractions, its activity was the highest in the subfraction III-c. Therefore butanol extract of garlic was suggested to be effective inhibitor of NDMA formation.