• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.517-522
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• 1998

Hydrocarbons in soybeans were analyzed to determine whether the hydrocarbons can be applied for detecting post-irradiation of soybeans. Yellow and green soybeans were irradiated at 0.5, 1, 3, and 6 kGy. Fats were extracted with hexane and then hydrocarbons were separated from the fat through Florisil column. The hydrocarbons were analyzed with GC. Hydrocarbons 17:2, 16:3, 17:1, and 16:2 were detected in the samples irradiated at 0.5 kGy or higher, but not in the unirradiated ones. The detection levels of hydrocarbons increased with the dose of the irradiation. When unirradiated or irradiated soybeans were roasted or boiled, these hydrocarbons were detected in the samples irradiated at 1 kGy or higher, but not in the unirradiated ones. A blind test confirmed that the hydrocarbon determining method could detect the soybeans irradiated at 1 kGy.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.770-776
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• 2001

To compare chemical properties of irradiated legumes (soybean, peanut, red bean, mung bean) produced in Korea and China, radiation-induced hydrocarbons from the samples were investigated. The legumes were gamma-irradiated at 0.5, 1, 2 and 4 kGy, from which lipid was extracted with hexane. Hydrocarbons were separated by florisil column chromatography and then analyzed with GC-MS method. The chromatograms of irradiated samples showed several radiation-induced hydrocarbons, which were affected by the fatty acid compositions of legumes. Hydrocarbons, such as 1, 7, 10-hexadecatriene (16:3),6,9-heptadecadiene (17 : 2), 1, 7-hexadecadiene (16 : 2) and 8-heptadecene (17 : 1), were predominantly detected in soybean, peanut and red bean irradiated at 0.5 kGy or above, whereas 17 : 1 was not found in mung bean. The detected amount of hydrocarbons increased with irradiation doses. There is no apparent difference in qualitative and quantitative profiles of the corresponding hydrocarbons depending on the origin of legumes.

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.10b
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• pp.106-106
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• 2003

Many polycyclic aromatic hydrocarbons (PAH) are acutely toxic to fish and other aquatic organisms in the presence of environmentally realistic intensities of solar ultraviolet radiation (SUVR). The phototoxicity of polycyclic aromatic hydrocarbons (PAHs) occurs through photodynamic activation of PAH compounds. Oxygen molecules react as quenchers with excited triplet states of PAHs producing reactive oxygen species (ROS).(omitted)

• Journal of the Korean Society of Combustion
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• v.13 no.1
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• pp.10-16
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• 2008

Numerical simulations of freely propagating premixed flames burning mixtures of methane and chlorinated hydrocarbons in fuel are performed at atmospheric pressure in order to understand the effect of chlorinated hydrocarbons on the formation of nitrogen oxide. A detailed chemical reaction mechanism is used, the adopted scheme involving 89 gas-phase species and 1017 elementary forward reaction steps. Chlorine atoms available from chlorinated hydrocarbons inhibit the formation of nitrogen oxides by lowering the concentration of radical species. The reduction of NO emission index calculated with thermal or prompt NO mechanism is not linear and is probably related to the saturation effect as $CH_3Cl$ addition is increased, In the formation or consumption of nitrogen oxide, the $NO_2$ and NOCl reactions play an important role in lean flames while the HNO reactions do in rich flames. The molar ratio of Cl to H in fuel has an effect on the magnitude of NO emission index.

• 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 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.

• Archives of Pharmacal Research
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• v.15 no.2
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• pp.109-114
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• 1992

For the risk assessment of human exposure to volatile halogenated hydrocarbons, a dynamic purge trap/on-column cryofocusing method using capillary gas chromatograph-$^{63}Ni$ electron capture detector and thermal desorption unit was applied to analyze the free forms, metabolites of 1, 1, 2-trichloroethylene and 1, 1, 2, 2-tetrachloroethylene. The urine sample was diluted with distilled water, hydrolyzed and sealed. Then the inert gas was infused to purge out free 1, 1, 2-trichloroethylene, free 1, 1, 2, 2-tetrachloroethylene and urichloroethanol. These compounds were trapped to $Tenax^R$ / GC-gas trap device throughout clean up tube. Being undertectable to gas chromatograph directly, trichloroacetic acid was methyl esterificated and trapped in the manner above mentioned. The optimal incubation time to get best recovery of methyl ester was 4 hours at $60^circ$C. The concentrations of free volatile halogenated hydrocarbons and their metabolites in urine were obtained of free volatile halogenated hydrocarbons and their metabolites in urine were obtained from 5 healthy volunteers. This analytical method is expected to make the biological monitoring more precise and convenient.

• Food Science of Animal Resources
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• v.31 no.6
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• pp.858-864
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• 2011

The effect of adding 10% fat substitute (10%F) or 2% plum extract (2%P) on the formation of hydrocarbons and 2-alkyl-cyclobutanones (2-ACBs) in freeze-dried beef patties, irradiated (IR) at 44 kGy, and freeze-dried irradiated cooked beef patties was investigated. Hydrocarbons, such as $C_{16:3}$, $C_{16:2}$, $C_{17:2}$ and $C_{17:1}$, were detected only in irradiated samples and their concentrations were high in the order of 2%P+IR, IR and 10%F+IR. Only irradiated beef samples produced 2-ACBs (2-DCB, 2-TCB, 2-TeCB), and their amounts were high in reverse order. The addition of fat substitute or plum extract did not help in reducing hydrocarbons and 2-ACBs in the freeze-dried irradiated cooked beef. However, the amounts of radiation-induced hydrocarbons and 2-ACBs in all irradiated beef patties even at 44 kGy were too small to be of concern for human consumption.

• Analytical Science and Technology
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• v.8 no.4
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• pp.807-814
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• 1995

Accurate measurements of ozone precursors are required to understand the process and extent of ozone formation in rural and urban areas. Nonmethane hydrocarbons (NMHCs) have been identified as important ozone precursors. Identification and quantification of NMHCs are difficult because of the large number present and the wide molecular weight range encountered in typical air samples. A major plan of the research team of the Climate and Air Quality Taiwan Station (CATs) was the measurement of atmospheric nonmethane hydrocarbons. An analytical method has been development for the analysis of the individual nonmethane hydrocarbons in ambient air at ppb (v) and subppb(v) levels. The whole ambient air samples were collected in canisters and analyzed by GC-FID with $Al_2O_3$/KCl PLOT column. Our targeted for quantitative analysis 43 compounds that may be substantial contributors to ozone formation. The retention indices and molar response factors of some commercially available $C_2{\sim}C_{10}$ hydrocarbons were determined and used to identify and quantify air samples. A quality assurance program was instituted to ensure that good measurements were made by participating in the International Nonmethane Hydrocarbon Intercomparison Experiments (NOMHICE).

• 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.