• Microbiology and Biotechnology Letters
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• v.19 no.1
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• pp.82-87
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• 1991

Xanthomonns curnpestris M12, Xunthornonas sp. M28, Acinetuhucter Iwofz GI, and Klebsiella pneumoniae L25, Pseudomonas rnaltophiliu N246 were screened to increase the ability for crude oil utilization. All of these could utilize hexadecane and octane with the exception of N246 strain for only octane biodegradation. Thus N246, M12, and M28, strains were specially examined for octane oxidation. Octane biodegradation by three strains showed the optimal conditions at $30^{\circ}C$, pH 7.0~9.0, and 0.2~0.3% octane concentration as a substrate. It was found that P. multofihila N246 and X. curnpestns M12 had plasmid and the cured plasmid from N246 strain lost octane uitilization. Therefore, it was confirmed that certain genes for octane utilization were Iocated on OCT plasmid in N246 strain. The size of OCT plasmid in N246 strain was 118 kb. The N246 strain was resistant to ampicillin.

• Fire Science and Engineering
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• v.27 no.2
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• pp.70-74
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• 2013

It is very important for the collected samples at fire scenes to be properly preserved for laboratory analysis. Preserving abilities of four type containers, metal cans, glass jars, zipper and heat sealed polymer bags, with the five ignitable liquids (toluene, n-octane, o-xylene, n-decane and n-hexadecane) were examined with gas chromatography-mass spectrometry. The glass jars with Teflon (PTFE) liner were the best ability to prevent the evaporation of the ignitable liquids.

• Journal of Environmental Science International
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• v.23 no.7
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• pp.1253-1268
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• 2014

This study was investigated twenty two hazardous chemicals compounds for effluents of nine sewage treatment plants (STPs) and one waste water treatment plant (WWTP) in the Nakdong Ri-ver Basin. They are eleven phthalates(DMP, DEP, DIBP, DBP, BEEP, DNPP, DHP, DCP, DEHP, DNOP, Dinonyl phthalate, seven aliphatic hydrocarbons(n-Tridecane, n-Tetradecane, n-Pentadecan-e, n-Hexadecane, n-Heptadecane, n-Octadecane, n-Nonadecane, Isoquinoline, 2-Chloropyridine, 2-N-itrophenol, and Benzophenone. The twenty two compounds were analyzed by gas chromatograp-hy mass spectrometry (GC/MS) with liquid-liquid extraction (LLE). Twenteen of twenty two subs-tances were detected. They were DMP, DEP, DIBP, DBP, DEHP, n-Tetradecane, n-Pentadecane, n-Heptadecane, n-Octadecane, n-Nonadecane, Isoquinoline and Benzophenone. Among these, DEHP, DEP and Benzophenone were most frequently observed. They were obtained as $ND{\sim}36.881{\mu}g/L$, $ND{\sim}0.950{\mu}g/L$, $ND{\sim}2.019{\mu}g/L$, respectively. When the substances were calculated the average concentration at 10 points, the maximum average detection concentration was investigated at the Dalseocheon STP.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.317-320
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• 2000

Effects of supplementing various 0.1-1.0%(w/v) surfactants and 0.1-1.0%(v/v) oxygen vectors on postthaw growth following cryopreservation of transgenic Nicotiana tabacum(GUS) in suspension culture were investigated. The postthaw cell growth was increased 20.68% and 23.66% compared to control when Pluronic F-68 and polyethylene glycol(PEG) were added in recovery medium respectively. Addition of n-hexadecane and FC-40 also enhanced the recovered growth by 14.89% and 20.68%. These results demonstrate that the marked Protection could be achieved by using surfactants and oxygen vectors for plant cells recovered from cryostorage.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.4 no.4
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• pp.221-225
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• 2000

Pseudomonas sp. EL-G527 was grown to produce a biosurfactant on 2% n-hexadecane as the energy and carbon source. This biosurfactant significantly reduced the surface tension of water from 72 to 28 dyne/cm at a critical micelle concentration(CMC) of 140 mg/l at pH 2.0. As the pH value decreased, the reduction in the surface tension due to the biosurfactant increased. The surface activity of the biosurfactant was unaffected when the NaCl concentration was increased to 5% and the calcium ion concentration increased to 100 mM, plus it remained stable at 10$0^{\circ}C$ for 180 min.

• Microbiology and Biotechnology Letters
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• v.24 no.2
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• pp.206-212
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• 1996

The strain producing bioemulsifier was isolated from soil samples. The isolated strain was identified as the genus Acinetobacter through its morphological, cultural and physiological characteristics. The highest emulsification activity and stability by Acinetobacter sp. BE-254 was observed after 5 days of cultivation in the culture medium containing n-hexadecane 4%, NaNO$_{3}$ 0.2%, KH$_{2}$PO$_{4}$ 0.01%, MgSO$_{4}$-7H$_{2}$O 0.01%, CaCl$_{2}$ 0.01%, and yeast extract 0.01%. The optimum pH and temperature for bioemulsifier production were pH 7.0 and 30$\circ$C, respectively. Furthermore the most of bioemulsifier was produced during the exponential growth phase, and this suggested that the bioemulsifier production was growth-associated. The bioemulsifier showed good emulsification activity on various emulsifying substrates such as hydrocarbons, edible oils, and petroleum fractions.

• Journal of Microbiology
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• v.39 no.4
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• pp.326-330
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• 2001

Mycobacterium sp. C2-3 was isolated from petroleum contaminated soil around an oil reservoir and identified by analysis of its 16S rRNA gene sequence, Strain C2-3 was able to use fluorene, phenan-threne, fluorathene and pyene as sole sources of carbon and energy, yet unable to geagrade naph-thalene, The strain was also able to use n-alkanes, such as hexadecane and heptadecane, and phenanthrene and pyrene, in particular, were degraded rapidly,. The phylogenetic data suggested that the isolate C2-3 is a thermosensitive, fast-growin strain of Mycobacterium sp.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.5
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• pp.172-180
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• 2006

This study was to analyze the effect of mixed fuel composition and mass fraction on the characteristics of evaporating diesel spray and combustion under the various ambient conditions. The characteristics of vaporization distribution and combustion were visualized by laser induced fluorescent method and direct photography. The experiments were conducted in the constant volume vessel and rapid compression expansion machine with optical access. Multi-component fuels mixed i-octane, n-dodecane and n-hexadecane were injected the vessel and rapid compression expansion machine with electronically controlled common rail injector. Experimental results show that fuel vapor formed stratified distribution. And vaporization and diffusion are become actively increasing in mass fraction of low boiling point component. Consequently multi-component fuels were expected to control the evaporating behavior according to their suitable mass fraction.

• Applied Chemistry for Engineering
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• v.9 no.3
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• pp.413-418
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• 1998

Methoxy polyoxyethylene dodecanoates are a kind of nonionic surfactants obtainable from reaction of fatty acid methyl ester with ethylene oxide utilizing a solid catalyst. Methoxy polyoxyethylene dodecanoates have economical advantage compared with polyoxyethylene dodecyl ethers using fatty alcohol. In this work, the solubilizing capacity concerned with phase behavior of ternary systems composed of nonionic surfactant/water/oil, interfacial tension and detergency at the phase inversion temperature(PIT) were investigated and compared with those of polyoxyethylene dodecyl ethers in order to confirm the applicability of methoxy polyoxyethylene dodecanoates in the detergents. Methoxy polyoxyethylene dodecanoates showed the solubilizing capacity of 10~18% for hexadecane which were about 6% higher than polyoxyethylene dodecyl ethers. At the PIT condition, methoxy polyoxyethylene dodecanoates' interfacial tension were 0.0124~0.0176 dyne/cm while polyoxyethylene dodecyl ethers have the value of 0.013~0.0163 dyne/cm and methoxy polyoxyethylene dodecanoates showed higher detergency of 82.1~83.2% than polyoxyethylene dodecyl ethers of 76.5~77.3%. The good detergency performance of methoxy polyoxyethylene dodecanoates would be due to the higher oil solubilizing power and lower interfacial tension than polyoxyethylene dodecyl ethers at the PIT condition.

• Korean Journal of Microbiology
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• v.34 no.3
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• pp.162-168
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• 1998

The characteristics of demulsification of petroleum emulsion by Streptomyces sp. 8321 were investigated. Demulsification ability of Streptomyces sp. 8321 appeared to be confined within the spores. Spore surface hydrophobicity was increased with culture age stimulating the demulsification ability. Over $1.1{\times}10^8spores/ml$ completely demulsified kerosene-0.2% Triton X-100 (2:1) emulsion. Among the low viscosity hydrocarbons, hydrocarbons with longer chain such as n-hexadecane and diesel were more rapidly demulsified. However, only 20-30% of the emulsion with high viscosity hydrocarbons was demulsified after 24 hours. Oil-in-water emulsions made by Corexit, Finalsol and BP series surfactants were completely demulsified within one minute. Demulsification rate ($t_{1/2}$) of oil-in-water emulsions made by Corexit 7664, 8667, Triton X-100 and Tween 80 decreased as their concentration increased. In case of water-in-oil emulsion made by Seagreen, $t_{1/2}$ was over 24 hours. Therefore, demulsification ability of Streptomyces sp. 8321 was more effective on oil-in-water emulsions.