• Journal of the Korean Society of Safety
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• v.32 no.2
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• pp.66-71
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• 2017

The autoignition temperature (AIT) is crucial combustible characteristics which need attention in chemical process that handle hazardous materials. The AIT, also to as minimum spontaneous ignition temperature(MSIT), is the lowest temperature of a hot surface at which the substance will spontaneously ignite without any obvious sources of ignition such as a spark or flame. The AIT may be used as combustion property to specify operating, storage, and materials handling procedures for process safety. This study measured the AITs of n-propanol+acetic acid system from ignition delay time(time lag) by using ASTM E659 apparatus. The AITs of n-propanol and acetic acid which constituted binary system were $435^{\circ}C$ and $212^{\circ}C$, respectively. The experimental AITs of n-propanol+acetic acid system were a good agreement with the calculated AITs by the proposed equations with a few A.A.D.(average absolute deviation). In the case of n-propanol and acetic acid system, the minimum autoignition temperature behavior (MAITB), which is lower than the lower AIT, is shown among the two pure substances constituting the mixture.

• Fire Science and Engineering
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• v.21 no.4
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• pp.32-37
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• 2007

An accurate knowledge of the flash point is important in developing appropriate preventive and control measures in industrial fire protection. The lower flash points for the 2-propanol+acetic acid and 2-propanol+-n-propionic acid systems were measured by Cleveland open cup apparatus. The experimental data were compared with the values calculated by the Raoult's law, the Wilson equation and the NRTL(non random two liquids) equation. The calculated values based on the Wilson and NRTL equations were found to be better than those based on the Raoult's law. And the predictive curve of the flash point prediction model, based on NRTL equation described the experimentally-derived data were more effective than the case of the Wilson equation.

• Bulletin of the Korean Chemical Society
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• v.15 no.5
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• pp.399-404
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• 1994

The non-Newtonian viscosities (the specific or intrinsic viscosities) of poly(L-proline) (PLP, $M_v$=19,000 and 32,000) in various mixed-solvent systems like water-propanol and acetic acid-propanol of varying compositions were measured during the reverse mutarotation (Form II ${\rightarrow}$Form I) by the application of external pressure (up to 4.5 psi). The non-Newtonian viscosity effect was found to be larger in acetic acid-propanol system than in water-propanol system and to somewhat decrease during the reverse mutarotation at a given solvent system. The non-Newtonian viscosity behavior of PLP in aqueous salt ($CaCl_2$) solution was also studied, from which it was found that the degree of the non-Newtonian effect decreased with increasing salt concentration, and increased with increasing PLP molecular weight. These findings could be explained in terms of conformational changes of PLP in solution (like the helix-helix or helix-coil transition) involved.

• Food Science and Preservation
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• v.19 no.3
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• pp.433-437
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• 2012

The fusel oils and the volatile flavor compounds of two potato sojues, one of which was produced with the traditional distillation apparatus(soju-gori) and the other, with the reduced pressure distillation system, were examined. The fusel oil content was high in the potato soju that was distilled under reduced pressure (potato soju(II)). The relative ratio of the isoamyl alcohol to the isobutyl alcohol and the n-propanol was 3.1:0.8:1.0 in the potato soju that was distilled with soju-gori (potato soju(I)), and 4.0:1.2:1.0 in potato soju(II). The chromatograms of the volatile components apparently differed between potato soju(I) and potato soju(II). Potato soju(I) contained four kinds of alcohol, six kinds of ester, n-valeraldehyde, and acetic acid. Potato soju(II) contained seven kinds of alcohol, 14 kinds of ester, two kinds of aldehyde, acetic acid, and three other compounds. Potato soju(II) significantly scored higher for flavor property than potato soju(I).