• Journal of ILASS-Korea
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• v.22 no.2
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• pp.80-86
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• 2017

The soot formation characteristics of various alkane-based single fuel droplets were studied in this work. Also, This study was performed to provide the database of the soot behavior and formation of alkane-based single fuel droplet. The experimental conditions were set to 1.0 atm of ambient pressure ($P_{amb}$), 21% of oxygen concentration ($O_2$) and 79% of nitrogen concentration ($N_2$). Combustion and soot formation of single fuel droplet was visualized by visualization system with high speed camera. At the same time, ambient pressure, oxygen concentration and nitrogen concentration were maintained by ambient condition control system. Soot formation characteristics was analyzed and compared on the basis of intensity ratio ($I/I_0$) of background image. The results of toluene fuel droplet showed the largest soot generation. Soot volume fraction ($f_v$) was almost the same under the identical fuel types regardless of various initial droplet diameter ($d_0$) since thermophoretic flux was not much changed under the same ambient conditions.

• Korean Journal of Microbiology
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• v.28 no.1
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• pp.71-75
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• 1990

The isolates biodigrading crude oil were examined to characterize thier properties. Isolates which were identified as Acinetobacter lwoffii G1, Klebsiella pneumoniae L25, Pseudomonas maltophilia N246, Xanthomonas campestris M12, and Xanthomonas sp. M28. The optimum concentration of crude oil was 0.15% for the bacterial growth. X. campestris M12, Xanthomonas sp. M28, and K. penumoniae L25 showed the maximal growth at the concentration of 3.5% sodium chloride, indicating that they were derived from sea water. Among the isolates, X. campestris M12, Xanthomonas sp. M28 specially utilized hexadecane and octane, and P. maltophilia N246 utilized octane with optimum concentration of 0.2-0.3% as sole carbon source. The utilization of components of saturate fraction by K. pneumoniae L25 was examined by gas-liquid chromatography. The short-chain saturates are used before the long chain ones although they almost disappear within 8 days of incubation at $30^{\circ}C$.

• Journal of the Korean Chemical Society
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• v.36 no.4
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• pp.485-495
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• 1992

The viscosities of organic compounds (alcohols, acetates, alkanes, acids, substituted $NH_2$) in liquid states, gas states and the binary mixtures of n-alkane / 1-chloroalkane were calculated by molecular modeling techniques. The molecular descriptors of molecular modeling technique are Molecular connectivity indices, Wiener indices and ad hoc descriptors, which can encode the information of compound properties about the effect of size, branching, cyclization, unsaturation, heteroatom content, polarizability, and so on. The successful results among method have been Molecular connectivity indices, binary mixtures of n-alkane / 1-chloroalkane, Wiener indices for gas state and ad hoc descriptor for liquid states. Also we obtained the regression equations for viscosities using molecular modeling indices for gas, liquid states and binary mixtures of n-alkane / 1-chloroalkane. The calculated viscosity values for organic compounds are in good agreement with experimental results.

• Bulletin of the Korean Chemical Society
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• v.32 no.11
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• pp.3909-3913
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• 2011

In this paper we have carried out molecular dynamics simulations (MD) for model systems of liquid n-alkane oligomers ($C_{12}{\sim}C_{80}$) at high temperatures (~2300 K) in a canonical ensemble to calculate viscosity ${\eta}$, self-diffusion constants D, and monomeric friction constant ${\zeta}$. We found that the long chains of these n-alkanes at high temperatures show an abnormality in density and in monomeric friction constant. The behavior of both activation energies, $E_{\eta}$ and $E_D$, and the mass and temperature dependence of ${\eta}$, D, and ${\zeta}$ are discussed.

• Elastomers and Composites
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• v.38 no.1
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• pp.51-56
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• 2003

Cloud-point and bubble-point data to $170^{\circ}C$ and 50 bar are presented for four different solvents, normal pentane. n-hexane, n-heptane, and n-octane with poly(ethylene-co-42 wt% octene) ($PEO_{42}$) copolymer. The pressure-concentration isotherms measured for $PEO_{42}$ - normal pentane have maximums at around 5 wt% of the copolymer concentrations in the solution. $PEO_{42}$- normal pentane system exhibits LCST-type phase behavior at temperatures greater than $130^{\circ}C$. Below $120^{\circ}C$, bubble-point type transitions are observed. However, the binary mixtures for $PEO_{42}$ in n-hexane, n-heptane, and n-octane have only bubble-point type transitions at the pressure-temperature region investigated in this study. The single-phase region of PEO - alkane mixtures increases with the molecular size of alkane solvent due to the increasing dispersion interactions between PEO and the alkane.

• Journal of Korea Soil Environment Society
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• v.5 no.2
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• pp.23-31
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• 2000

The objective of this study was to develop an effective separation and quantification method for kerosene and diesel in a mixed petroleum fuel (gasoline, kerosene, and diesel) contaminated environmental samples. This investigation was directed to prove the hypothesis that if the source of petroleum fuels were identical, the peak-area ratios of a reference n-alkane to other n-alkane peaks should be a constant even at the different concentrations. In addition, experimental recovery rates were determined to select the reference peaks of kerosene and diesel for peak area ratio measurements. The experimental results showed that the peak area ratios were constant among the samples having different concentrations when the ratios were calculated from areas of $C_{l3}$, $C_{l4}$, and $C_{15}$ peaks for kerosene and $C_{l6}$ and $C_{l7}$ peak for diesel as reference n-alkane peaks. The recovery rates were evaluated by comparing the relative peak area ratios of each reference peaks after making pairs of the kerosene and diesel reference peaks in the samples contained a known amount of gasoline, kerosene, and diesel. The recovery rates(%) Were 107.0$_{{\pm}20.6}$/86.6/ sub $\pm$15.9/ for kerosene- $C_{13}$/diesel- $C_{16}$, 99.6$\pm$$_{17.2}$/86.6$_{{\pm}15.9}$ for kerosene- $C_{14}$/diesel- $C_{16}$, 73.9/$\pm$14.4//86.6$_{{\pm}sub 15.9}$ for kerosene- $C_{15}$ /diesel- $C_{16}$, 109.4$_{{pm}0.8}$/75.9$_{{pm}4.7}$ for kerosene- $C_{13}$/diesel- $C_{17}$, 107.4$_{{pm}7.9}$/75.9$_{{pm}4.7}$ for kerosene- $C_{14}$/diesel- $C_{17}$, and 95.7$_{{pm}4.6}$ /75.9/$\pm$14.6//75.9$_{{pm$}4.7}$ for kerosene- $C_{15}$ /diesel- $C_{17.}$ The above experimental results confirm that all of the reference peak pairs of kerosene and diesel are applicable to the quantitative analysis for the mixed fuel contaminated samples, but the kerosene- $C_{15}$ /diesel- $C_{l7}$ peaks are recommended since the pair has a lower standard deviation than the other pairs.s..s.s.s..s..s.s.s.s.s.

• Rapid Communication in Photoscience
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• v.2 no.1
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• pp.31-33
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• 2013

The irradiation of electron-beam onto bis-(diphenylphosphino)methane, ethane, propane and butane initiated phenyl-shift from a phosphine to another phosphine atom and subsequent fragmentation resulted in the formation of triphenylphosphine derivative as key intermediate. The mechanism of those processes is speculated.

• Bulletin of the Korean Chemical Society
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• v.24 no.12
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• pp.1835-1837
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• 2003

• Journal of Environmental Health Sciences
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• v.11 no.2
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• pp.65-75
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• 1985

Microorganisms capable of utilizing diaminododecane containing amine groups diterminally were isolated from the soil by enrichment culture. One strain of these isolated strain, designated as EL-0112L, was selected for this study. The results of this study were as follows. 1. This isolated strain EL-0112L was identified as Microbacterium, from the results of morphological, cultural, and biochemical tests. This isolated strain was named temporarily Microbacterium sp. EL-0112L for convenience. 2. Microbacterium sp. EL-0112L was tested for ability to utilize different kinds of substitued alkanes containing cyan, amine, chloro, and thiol groups(monoterminally or diterminall substituted) as carbon source. Pentamethylenediamine, hexamethylenediamine, n-decane, laurylamine, and alkane derivatives containing cyan, chloro, and thiol groups were not utilized by Microbacterium sp. EL-0112L. 3. The alkane derivatives that did not serve as growth substrates were tested further in oxidation tests using resting cell preparation of Microbacterium sp. EL-0112 L. Alkane derivatives containing cyan, chloro, thiol groups, and n-decane were oxidized by Microbacterium sp. EL-0112 L. It is possible that this isolated strain is also able to degrade their substituted counterparts since they are structually similar to diaminododecane. The remarkable substrates that were being oxidized were dichlorodecane, and 1-dodecanethiol. Microbacterium sp. EL- 0112L could not oxidize pentamethylenediamine, and hexamethylenediamine. 4. The metabolic products formed from diaminododecane by Microbacterium sp. EL-0112 L were acid compound containing carboxyl group and not containing amine group. On the thin layer chromatography, Rf values of these metabolic products were different from that of the product formed by Corynebacterium sp. EL-0112L. These results suggested the specificity of diaminododecane as carbon source.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.2
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• pp.209-212
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• 2002

The understanding of seasonal forage intake of grazing deer is essential for the development of supplementary feeding strategies in southern Australia. The alkane technique is used in other animal species for estimating feed intake of individual animals and their diet composition. To assess the potential of using alkanes as a marker for predicting feed intake of fallow deer, the daily faecal recovery of alkanes and excretion rate of dosed artificial alkanes (C32 and C36) were measured with 6 deer fed three forage based diets. The artificial alkane capsule designed for use in sheep is suitable for fallow deer. Faecal samples need to be collected over days 7-19 after dosing. The daily excretion rate was 40 mg for C32 and 37 mg for C36. The faecal recovery of natural alkanes is incomplete and the faecal concentrations of alkanes need to be adjusted for an accurate estimation of intake. The actual feed intake of 6 experimental deer over a 5 day period was accurately estimated ($R^2$=0.52) using alkanes.