• Journal of the Korean Society of Safety
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• v.34 no.1
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• pp.34-39
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• 2019

Flash point is the important indicator to determine fire and explosion hazards of liquid solutions. In this study, flash points of n-propanol+n-hexanol and n-butanol+n-hexanol systems were obtained by Seta flash tester. The methods based on UNIFAC equation and multiple regression analysis were used to calculate flash point. The calculated flash point was compared with the experimental flash point. Absolute average errors of flash points calculated by UNIFAC equation are $2.9^{\circ}C$ and $0.6^{\circ}C$ for n-propanol+n-hexanol and n-butanol+n-hexanol, respectively. Absolute average errors of flash points calculated by multiple regression analysis are $0.5^{\circ}C$ and $0.2^{\circ}C$ for n-propanol+ n-hexanol and n-butanol+n-hexanol, respectively. As can be seen from AAE, the values calculated by multiple regression analysis are noticed to be better than the values by the method based on UNIFAC eauation.

• Journal of the Korean Institute of Gas
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• v.12 no.3
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• pp.50-55
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• 2008

The flash points for the systems, ethlybenzene+n-butanol and ethlybenzene+n-hexanol, were measured by using Tag open-cup tester (ASTM D1310-86). These binary mixtures exhibited MFPB (minimum flash point behavior), which leads to the minimum on the flash point vs composition curve. The experimental data were compared with the values calculated by the Raoult's law, the UNIQUAC equation and the NRTL equation. The calculated values based on the UNIQUAC and NRTL equations were found to be better than those based on the Raoult's law. It was concluded that the UNIQUAC and NRTL equations were more effective than the Raoult' law at describing the activity coefficients for nonideal solution such as the ethlybenzene+n-butanol and ethlybenzene+n-hexanol systems. And the predictive curve of the flash point prediction model based on the NRTL equation described the experimentally-derived data more effectively than was the case when the prediction model was based upon the UNIQUAC 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.

• Applied Chemistry for Engineering
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• v.22 no.5
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• pp.447-452
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• 2011

Depletion of petroleum increased the need of alternative energy and chemical resources. Biomass, a renewable resource, can be transformed to bioenergy and biomaterials, and the materials from biomass will ultimately substitute petroleum based energy and chemical compounds. In this perspective, production of C4-C6 compounds for bioenergy and biomaterials are described for understating of current research progress. n-Butanol and n-butyric acid, the major C4 compounds, are produced by Clostridium tyrobutyricum, Clostridium beijerinckii, and Clostridium acetobutylicum. n-Hexanoic acid, a typical C6 compound, is produced by Clostridium kluyveri and Megasphaera elsdenii. Reported maximum amount of n-butanol, n-butyric acid and n-hexanoic acid was 21, 55, and 19 g/L, respectively, and extraction of these C4-C6 compounds are induced increase production by those anaerobic bacteria. In addition, a new bacterium Clostridium sp. BS-1 produced 5 g/L of n-hexanoic acid using galactitol.

• International Journal of Safety
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• v.8 no.2
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• pp.15-19
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• 2009

The flash point is the most widely used flammability property for the evaluation of the flammability hazard of combustible liquid mixtures. In this paper, the reported flash points for the the binary systems, ethylbenzene+n-butanol and ethylbenzene+n-hexanol were correlated by the optimization method. The optimization method based on the van Laar and Wilson equations were compared with the Raoult's law. The calculated values based on the optimization method were found to be better than those based on the Raoult's law.

• Journal of the Korean Chemical Society
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• v.38 no.8
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• pp.539-546
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• 1994

The critical micelle concentration(CMC) and the counterion binding $constant(\beta)$ at the CMC of cetyltrimethylammonium bromide(CTAB) in a series of aqueous solutions containing medium chain-length n-alcohols(Propanol, Butanol, Pentanol and Hexanol) have been determined from the concentration dependence of electrical conductance at serveral temperature from $17^{\circ}C\;to\;41^{\circ}C.$ Thermodynamic parameters $({\Delta}G^o_m,\;{\Delta}H^o_m,\;{\Delta}S^o_m,\;and\;{\Delta}C_p)$ associated with micelle formation of CTAB have been also estimated from the temperature dependence of CMC and $\beta$ values, and the significance of these parameters and their relation to the theory of micelle formation have been considered. The results show that an enthalpy-entropy compensation effect is usually observed for the micellization of CTAB. The effects of n-alcohols on the micellar properties (CMC and $\beta$) of CTAB solutions have been also investigated. The addition of n-alcohol to the CTAB solution in a small quantity decreases the CMC value and the counterion binding constant $(\beta)$ at the CMC, but the addition of n-alcohol in an excessive quantity increases the CMC values on the conterary. These results have been explained in terms of the effect of the micelle-solubilized alcohol on the micellar surface charge density.

• Microbiology and Biotechnology Letters
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• v.27 no.2
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• pp.107-112
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• 1999

A bacterium, which can utilize cyclohexanol as a sole source of carbon and energy, was isolated from sludge in sewage of Ulsan Industrial Complex for Petrochemicals, Korea and identified as Rhodococcus sp. TK6. The growth conditions of the bacteria were investigated in cyclohexanol containing media. The bacteria utilized cyclohexanol, cyclohexanone, cyclohexane-1,2=diol, cyclopentanol, cyclopentanone, and $\varepsilon$-caprolactone but not cyclohexane, cyclohexane-1,2-dione, and cyclooctanone. The bacteria were able to utilize alcohols such as ethanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 2-methyl-1-propanol, 3-methyl-1-butanol, 2-propanol, and 2-butanol as well as cyclohexanol, organic acids such as adipate, propionate, butyrate, valerate, n-caproate, and 6-hydroxycaproate, and aromatic compounds such as phenol, salicylate, p-hydroxbenzoate, and benzoate as a sole source of carbon and energy. Cyclohexanone as a degradation product of cyclohexanol by Rhodococcus sp. TK6 was determined with gas chromatography.

• The Korean Journal of Pain
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• v.6 no.2
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• pp.237-246
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• 1993

세포막에서 마취제의 작용점을 규명하기 위하여, 마취제의 많은 부분을 차지하는 n-Alkanol을 이용하여, 소의 synaptosomal plasma membrane vesicles(SPMV)에서 n-Alkanol의 침투 정도를 형광 probe를 이용한 형광소광법을 통하여 검색하였다. n-Alkanols는 SPMV 외부 단층(outer monolayer)의 표면에 주로 분포하되 그 탄소수에 비례하여 소수성 부위에 분포되는 양이 증가되는 경향을 나타내었다(1-decanol은 제외). Methanol, Ethanol, 1-propanol, 1-butanol, 1-pentano, 1-hexanol, 1-heptanol, 1-octanol, 1-nonanol 및 1-decanil은 SPMV 외부 단층의 표면(친수성 부위)에 분포되는 것에 비하여 각각 949, 416.8, 214.8, 90.3, 53.7, 15.20, 6.80, 2.00, 1.03 및 2.40 배가 된다는 것을 확인하였다. 1-decanol은 $C_{10}$인데도 불구하고 $C_8$인 1-octanol에 비하여 적은 양이 소수성 부위에 침투 분포한다는 것이 확인되었다.

• The Korean Journal of Pain
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• v.6 no.1
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• pp.74-82
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• 1993

신선한 소의 대뇌피질로부터 synaptosomal plasma membrane vesicles(SPMV)를 분리하고 이 SPMV로부터 추출한 총지질(cholesterol과 각종 인지질 함유)로서 제제한 인공세포막(SPMVTL)에서의 n-alkanols 침투 정도를 형광 probe를 이용한 형광 소광법을 통하여 검색하였다. n-alkanols는 SPMVTL 외부 단층(outer monolayer)의 표면에 주로 분포하되 그 탄소수에 비례하여 소수성 부위에 분포되는 양이 증가되는 경향을 나타내었다(1-decanol은 예외). Methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-hepatnol, 1-cotanol, 1-nonanol 및 1-decanol은 SPMVTL 외부 단층 표면(친수성 부위)에 분포되는 것이 소수성 부위에 분포되는 것에 비하여 각각 650, 288, 151.6, 69.5, 36.8, 11.9, 4.8, 1.6, 0.74, 2.1배가 된다는 것을 확인하였다. 1-decanol은 $C_{10}$인데도 불구하고 $C_8$인 1-octanol에 비하여 적은 양이 소수성 부위에 침투 분포되는 것이 확인되었다. 또한 n-alkanols는 저자등이 이미 보고한 SPMV에서의 경우보다도 본 연구에서의 SPMVTL의 경우가 현저하게 많은 양이 소수성 부위로 침투 분포된다는 것이 확인되었다.

• The Korean Journal of Pain
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• v.6 no.1
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• pp.67-73
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• 1993

소의 신선한 대뇌피질로부터 synaptosomal plasma membrane vesicles(SPMV)를 분리한 후 이 SPMV로부터 추출한 모든 인지질들로서 제제한 인공세포막(SPMVPL)에서의 n-alkanols 침투 정도를 형광 probe를 이용한 형광 소광법을 통하여 검색하였다. n-alkanols는 SPMVPL 외부 단층(outer monolayer)의 표면에 주로 분포하되 그 탄소수에 비례하여 소수성 부위에 분포되는 양이 증가되는 경향을 나타내었다. methanol, ethanol, 1-propano, 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 1-nonanol 및 1-decanol은 SPMVPL 외부 단층의 표면(친수성 부위)에 분포되는 것이 소수성 부위에 분포되는 것에 비하여 각각 432.4, 208.9. 125.6, 88.2, 19.3, 7.9, 2.6, 1.0, 0.42, 1.36배가 되었다. 1-decanol은 $C_{10}$인데도 불구하고 $C_8$인 1-octanol에 비하여 적은 양이 소수성 부위에 침투 분포된다는 것이 확인되었다. n-alkanols의 침투에 대하여 저자등이 이미 보고한 바 있는 SPMV 및 SPMVTL(cholesterol+phospholipids)의 경우보다도 본 연구에서의 SPMVPL의 경우가 현저하게 많은 양이 소수성 부위로 침투 분포된다는 것도 확인되었다.