• Korean journal of applied entomology
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• v.42 no.1
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• pp.9-13
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• 2003

Cuticular hydrocarbons of antenna, legs and wings from two species of honeybee worker of Apis mellifera L. and Apis cerana F. can be analyzed directly with gas chromatograph and GC/MS without solvent extraction. The saturated hydrocarbons identified in selected part of both species were nC22, nC23, nC25-nC3O, nC32 and nC34 except nC24. Two saturated hydrocarbons, nC26 (23.0-42.6%) and nC28 (16.8-54.8%), were major compounds in both species and others were minor compounds. A. mellifera can be distinguished from A. cerana F. by having higher proportion of nC30, nC32 and nC34 by having lower proportion of nC25 from three selected part of both species.

• Journal of Korean Society on Water Environment
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• v.21 no.5
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• pp.442-447
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• 2005

Concentrations of aliphatic hydrocarbons in water, particulate matter, and sediment phase were measured at five stations in Gyeongan River. Aliphatic hydrocarbons from $n-C_{10}$ to $n-C_{17}$ were detected in the water phase and they might be originated from not only biogenic hydrocarbons also petroleum hydrocarbon. $n-C_{17}$ aliphatic hydrocarbon and fatty acids were detected in the particulate matter phase. They might be originated from biological sources such as phytoplankton. Short alkane chains from $n-C_{10}$ to $n-C_{13}$ were detected in the sediment phase. They might be originated from sedimentation of biological hydrocarbons decomposed by bacteria or adsorption of petroleum hydrocarbon from the water phase.

• Journal of the Korean Chemical Society
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• v.7 no.2
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• pp.128-132
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• 1963

A study has been made on the applicability of gas-liquid partition chromatography to the qualitative and quantitative analysis of complex mixture of gaseous hydrocarbons. While phthalate columns are widely used for this $purpose^9$, they separates neither saturated hydrocarbons from the unsaturated nor n-butane from isobutene or butene-1, therefore combined columns such as phthalate and dimethylsulfolane have been used for the perfect separation of gaseous hydrocarbons. It is shown by this study, however, that hydrocarbons having $C_1$ through $C_4$ can be separated with a 2-meters tetraethyleneglycol dimethylether column except ethane from ethylene, and trans-from cis-2-butene especially operated at $15^{\circ}C$$ using helium as the carrier gas. The column effluents were in order of methane, (ethane, ethylene), propane, propylene, isobutane, n-butane, isobutylene, butene-1, (trans-& cis-2-butene, isopentane), (butadiene-1, 3, n-pentane). Two kinds of liquified petroleum gases in market are analysed qualitatively and quantitatively. The results indicate that use of this 2-meters TEGDE column permits the separation and identification of all the commonly encountered aliphatic gaseous hydrocarbons.

• Journal of the Korean Society of Safety
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• v.17 no.4
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• pp.126-132
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• 2002

By using the reference data, the empirical equations which describe the interrelationships of explosion properties and physical properties of n-chlorinated hydrocarbons have been derived. The properties which have been correlated are the lower and upper explosive limits, the stoichiometric coefficients, the heats of combustion, the carbon numbers. Also, the new equations using the mathematical and statistical methods for predicting the temperature dependence of lower explosive limits(LEL) of chlorinated hydrocarbons on the basis of the literature data are proposed. The fire and explosion properties calculated by the proposed equations in this research were a good agrement with literature data within a few A.A.P.E.(Average Absolute Percent Error) and A.A.D.(Average Absolute Deviation.) From a given explosive properties, by using the proposed equations, it is possible to predict to the fire and explosion characteristics for the other chlorinated hydrocarbons.

• Journal of Microbiology and Biotechnology
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• v.11 no.1
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• pp.56-60
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• 2001

A kerosene fungus of Cladosporium resinae NK-1 was examined for its ability to degrade individual n-alkanes and aromatic hydrocarbons by gas chromatography-mass spectrometry, and its organic solvent-tolerance was investigated by making use of the water-organic solvent suspension culture method. It grew on a wide range of solvents of varying hydrophobicities and it was found to have tolerance to various kinds of toxic organic solvents (10%, v/v) such as n-alkanes, cyclohexane, xylene, styrene, and toluene. A hydrocarbon degradation experiment indicated that NK-1 had a greater n-alkane degrading ability compared to that of the other selected strains. C. resinae NK-1, which could utilize 8-16 carbon chain-length n-alkanes of medium chain-length as a carbon source, could not assimilate the shorter chain-length n-alkanes and aromatic hydrocarbons tested so far. The n-alkane degrading enzyme activity was found in the mycelial extract of the organism.

• Bulletin of the Korean Chemical Society
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• v.34 no.10
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• pp.3005-3012
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• 2013

The effect of Mn-promotion on high surface area Al-pillared montmorillonite (AlMMT) supported Co nanoparticles prepared by hydrothermal method have been investigated. A series of different weight% Mn-promoted Co nanoparticles were prepared and characterized by XRD, TPR, TGA, BET and SEM techniques. An increase in the surface area of MMT is observed with Al-pillaring. Fischer-Tropsch catalytic activity of the as prepared catalysts was studied in a fixed bed micro reactor at $225^{\circ}C$, $H_2/CO$ = 2 and at 1 atm pressure. The data showed that by the addition of Mn the selectivity of $C_1$ dropped drastically while that of $C_2-C_{12}$ hydrocarbons increased significantly over all the Mn-promoted Co/AlMMT catalysts. The $C_{13}-C_{20}$ hydrocarbons remained almost same for all the catalysts while the selectivity of $C_{21+}$ long chain hydrocarbons decreased considerably with the addition of Mn. The catalyst with 3.5%Mn showed lowest $C_{21+}$ and highest $C_2-C_{12}$ hydrocarbons selectivity due to cracking of long chain hydrocarbons over acidic sites of MMT.

• Environmental Engineering Research
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• v.25 no.3
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• pp.290-298
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• 2020

A large residual fraction of aliphatic components of diesel prevails in soil, which has adverse effects on the environment. This study identified the most bio-recalcitrant aliphatic residual fraction of diesel through total petroleum-hydrocarbon fractional analysis. For this, the strain Acinetobacter sp. K-6 was isolated, identified, and characterized and investigated its ability to degrade diesel and n-alkanes (C₁₈, C₂₀, and C₂₂). The removal efficiency was analysed after treatment with bacteria and nutrients in various soil microcosms. The fractional analysis of diesel degradation after treatment with the bacterial strains identified C₁₈-C₂₂ hydrocarbons as the most bio-recalcitrant aliphatic fraction of diesel oil. Acinetobacter sp. K-6 degraded 59.2% of diesel oil and 56.4% of C₁₈-C₂₂ hydrocarbons in the contaminated soil. The degradation efficiency was further improved using a combinatorial approach of biostimulation and bioaugmentation, which resulted in 76.7% and 73.7% higher degradation of diesel oil and C₁₈-C₂₂ hydrocarbons, respectively. The findings of this study suggest that the removal of mid-length, non-volatile hydrocarbons is affected by the population of bio-degraders and the nutrients used in the process of remediation. A combinatorial approach, including biostimulation and bioaugmentation, could be used to effectively remove large quantities of aliphatic hydrocarbons persisting for a longer period in the soil.

• Journal of the Korean Society of Food Culture
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• v.22 no.2
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• pp.246-253
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• 2007

Mineral and volatile flavor compounds of Pimpinella brochycarpa N., a perennial Korean medicinal plant of the Umbelliferae family, were analyzed by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and simultaneous steam distillation extract (SDE)-gas chromatography mass spectrometry (GC/MS), head space solid phase micro-extraction (HS-SPME)-GC/MS. Mineral contents of the stalks and leaves were compared and the flavor patterns of the fresh and the shady air-dried samples were obtained by the electronic nose (EN) with 6 metal oxide sensors. Principal component analysis (PCA) was carried out using the data obtained from EN. The 1st principal values of the fresh samples have + values and the shady air-dried have - values. The essential oil extracted from the fresh and the shady air-dried by SDE method contain 58 and 31 flavor compounds. When HS-SPME method with CAR/PDMS fiber and PDMS fiber were used, 34 and 21 flavor compounds. The principal volatile components of Pimpinella brachycarpa N. were ${\alpha}$-selinene, germacrene D, and myrcene.

• Applied Biological Chemistry
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• v.34 no.4
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• pp.366-372
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• 1991

The volatile components, normal hydrocarbons, organic acids, and nonvolatile fatty acids in the various parts of Luffa cylindrica(L.) Roemer(sponge-gourd) were analyzed by GC and GC/MS. More than 150 volatile components were separated and thirty seven components were identified and quantified. The contents of essential oil were 0.05%, 0.05%, and 0.08% on a dried weight base in leaves, stem, and seeds respectively. Fruit juice and sap contained 0.06% and 0.03% oil on the fresh weight base. Twenty six components of normal hydrocarbons in leaves, stem, seed, and unripe fruit were separated, identified, and quantified. The total concentrations of the hydrocarbons were $75.5\;{\mu}g/g$ in leaf, $52.0\;{\mu}g/g$ in stem, $46.6\;{\mu}g/g$ in fruit juice, and $32.8\;{\mu}g/g$ in seed fractions. The major hydrocarbons in leaves, stem, and fruit juice were $nC_{25}$, $nC_{27}$, $nC_{29}$, and $nC_{31}$, $nC_{16}$, $nC_{17}$, $nC_{18}$, and $nC_{19}$ were abundant in seeds mainly. The concentration of malonic acid among the five organic acids was highest in leaves, stem, and flowers. Unripe fruit contained 24.5 mg/g of the five organic acids and malic and citric acids were higher. The concentrations of palmitic, linoleic, and linolenic acids were higher concentration in the various parts of sponge-gourd and palmitic acid was distributed in the most parts. The concentrations of organic and fatty acids in the sap were negligible.

• Journal of the Korean GEO-environmental Society
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• v.20 no.1
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• pp.5-11
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• 2019

The main objective of this study was to analyse polycyclic aromatic hydrocarbons in surface sediments obtained from near Nakdong estuary, and to estimate ecological risks of PAHs using PAHs concentrations. The main constituents of sediments were $SiO_2$, $Al_2O_3$, CaO, $Fe_2O_3$, and ignition loss of sediments ranged from 2.97% and 8.39%. Total concentrations of PAHs ranged from $128.4ng\;g^{-1}$ and $507.4ng\;g^{-1}$, and the major PAHs were 2 ring and 4 ring aromatic hydrocarbons. Each concentrations of PAHs are all below effect range low, which indicated that each PAHs in 8 studying sites show low ecological risk. From M-ERM-Q analyses, M-ERM-Q values of 8 studying sites are below 0.1 indicating low ecological risk. From source apportionment analyses, PAHs come from grass, wood, charcoal combustion for N-1 and N-7, petroleum combustion for N-5 and N-6, petroleum pollution for N-2, N-3, N-4, N-8.