• Applied Biological Chemistry
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• v.40 no.5
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• pp.442-446
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• 1997

A new analytical method was developed by HPLC after supercritical fluid extraction and fluorogenic derivatization for the determination of quinclorac (3,7-dichloro-8-quinoline carboxylic acid) in soil. The graminicide quinclorac was extracted from soil by supercritical fluid extraction. Supercritical carbon dioxide at 7000 psi $(80^{\circ}C)$ modified with 30% of methanol extracted quinclorac from soil samples at the level of $0.1ng\;g^{-1}$ with 96% recovery. Extracted quinclorac was determined by HPLC as a fluorescent derivative. Derivatization was made with 4-bromomethyl-7-methoxycoumarin (4-Br-Mmc) using 18-crown-6-ether as a catalyst. The conversion was completed within 30 min and the limit of detection was 0.5 ppb to prove that the procedure could be used in the residue analysis of the pesticides containing carboxylic acid group.

• KSBB Journal
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• v.14 no.5
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• pp.633-637
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• 1999

Supercritical fluid of carbon dioxide was used to investigate the effects of its temperature and density on the distribuion coefficients of fatty-acid esters composing fish oil. The distribution coefficient of fatty acid ester was greatly different from each other according to the temperature and density of the supercritical fluid. The possibility of separation of a certain fatty acid from the mixture of fatty acids was tested. The density of the supercritical fluid showing the great differences ofthe distribution coefficients among the fatty acid esters ranged from 0.3 g/mL to 0.4 g/mL. The retrograde condensation took place at high densities of the supercritical fluid.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.571-571
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• 2003

• Proceedings of the Korean Nuclear Society Conference
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• 2003.05a
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• pp.386.1-386.1
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• 2003

• Food Industry And Nutrition
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• v.17 no.1
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• pp.17-24
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• 2012

• Food Industry And Nutrition
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• v.6 no.2
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• pp.13-19
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• 2001

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2019.05a
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• pp.309-310
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• 2019

• Bulletin of the Korean Chemical Society
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• v.25 no.4
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• pp.471-475
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• 2004

The solubility of N,N'-Bis(salicylidene) ethylenediamine (n-salen) and N,N'-bis(3,5-di-tert-butylsalicylidene) ethylenediamine (t-butyl-salen) was studied with in-situ UV-VIS spectrometer. n-Salen is 3-5 times more soluble than t-butyl-salen in liquid or supercritical $CO_2$. This behavior may be attributed to Lewis acid-base interaction between salen and $CO_2$. The chelation of salen with $Co^{++}$ ion in supercritical condition was confirmed to be fast enough above room temperature. However, the metal ion extraction capability of t-butyl salen is relatively poor because of its low solubility and ionic nature of complex.

• Journal of the Korean Society of Industry Convergence
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• v.10 no.2
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• pp.97-104
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• 2007

In different approaches were extracted from evening primrose seed by supercritical fluids carbon dioxide and for comparison with hexane as solvent. The extracts have been analyzed qualitatively and quantitatively to evaluate yield and selectivity of ${\gamma}$-linolenic acid. The yields extracts with supercritical fluids carbon dioxide were higher than those with hexane. When this process produces commercially, will get a many economic profit.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.10
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• pp.1439-1443
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• 2006

This study was performed on the effects of extraction temperature, pressure, time on apparent solubility and extraction yield of perilla oil and tocopherol, and color and fatty acid composition of the residue in supercritical carbon dioxide $(SC-CO_2)$ extraction. Apparent solubility of perilla oil and tocopherol increased with the increase of $CO_2$ density and was found to strongly depend on extraction pressure rather than extraction temperature. The extract yield of tocopherol in $SC-CO_2$ extraction increased with an increase of temperature and decreased with an increase of pressure and extraction time. The perilla oil apparent solubility of dried perilla powder for $60\sim180$ min at $40^{\circ}C/276$ bar increased with an extraction time, on the other hands, tocopherol apparent solubility decreased. As the increase of $CO_2$ density, less redness and yellowness increased. Fatty acid composition of perilla oil showed that perilla oil extracted by $SC-CO_2$ had better unsaturated fatty acid and decreased in saturated fatty acid. $SC-CO_2$ extraction offers a safe natural method for gaining perilla oil from dried perilla seeds powder.