• Journal of the Korean Society of Food Science and Nutrition
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• 제31권1호
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• pp.26-31
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• 2002

Volatile compounds from three parts of needles, sprouts and twigs in Pinus densiflora were extracted by solid phase microextraction (SPME) and dynamic headspace analysis (DHA). separated by gas chromatography, and identified by using mass selective detecter and Kovat's retention index. The amounts of monoterpenes isolated by SPME and DHA were 66.7% and 14.3% in needles, 90.6% and 0.7% in sprouts, and 90.6% and 1.2% in twings, respectively. The amounts of sesquiterpenes detected only by SPME were 25.8% in needles, 4.4% in twings and 1.5% in sprouts. And the amounts of oxygenated terpenes isolated by SPME and DHA were 4.7% and 79.0% in sprouts, 3.7% and 70.4% in twigs, and 1.0% and 50.7% in needles, respectively. The kinds of volatile compounds isolated by SPME were similar to those by solvent extraction, but the number of compounds identified to hate a boiling point below 5$0^{\circ}C$ by UHA was larger than that of SPME.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 한국지하수토양환경학회 1998년도 공동 심포지엄 및 추계학술발표회
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• pp.57-59
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• 1998

The headspace method has been acknowledged as a cost-effective and convenient method to analyze volatile organic compounds(VOCs) in soil. The headspace analysis is based on equilibrium partitioning of VOCs among water, air and soil in a closed system. However, the headspace method cannot be applied to soils where most of the VOCs remain sorbed even at high temperature. In this study, it was investigated how the sorption characteristics of VOCs varied with soil with different organic carbon contents and temperature. This study showed that all the VOCs were volatilized, not sorved, only in the soil with 5% organic carbon at 45$^{\circ}C$ or higher. Some fraction of VOCs remained in soil with 8% organic carbon at $65^{\circ}C$ of higher. Most of the VOCs remained sorbed in soil with 12% organic content even at 95$^{\circ}C$. This result suggested that the headspace method can be applied only to soils with little organic carbon content (less than 5%). In this case, 45$^{\circ}C$ seems to be high enough to volatilize all the VOCs from soil. Large particles still showed a significant sorption capacity for VOCs from soil. Large Particles still showed a significant sorption capacity for VOCs despite of their low level of organic carbon content. It was also shown that the organic carbon sorption coefficients (Koc) of VOCs varied with soils with different organic carbon content. This suggests that not only the organic matter content of soil but also the property of the organic matter in soil influence the sorption of VOCs to soil.

• Applied Biological Chemistry
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• 제40권2호
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• pp.144-147
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• 1997

Different isolation methods for the volatile components of Anise(Pimpinella anisum L.) are compared in terms of the difference of components obtained with each analytical procedure. These methods include headspace(purge & trap) sampling procedure, simultaneous distillation extraction(SDE), steam distillation and solvent extraction. Total 43 components were identified by? comparing gas chromatography retention time and mass spectral data. Different isolation techniques result in compositionally different isolates. The headspace(purge & trap) sampling procedure was found to be the best method of choice for a qualitative analysis of the volatile components.

• Korean Journal of Food Science and Technology
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• 제28권6호
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• pp.1177-1179
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• 1996

A static headspace gas chromatographic (HSGC) technique was used to quantify toluene and other solvents (methanol, isopropyl alcohol, methyl ethyl ketone and ethyl acetate) in food packaging films. Comparison of retention times and coefficient variations for standard solvents showed consistent retention time and good reproducibility. Therefore, this method using static HSGC proved to be superior in rapidity and reproducibility, and is thought to be adaptable to analysis of a large number of samples. The methanol content was $N.D.\;(not\;detected){\sim}0.939\;mg/m^2$, toluene $N.D.{\sim}1.403\;mg/m^2$, melthyl ethyl ketone $N.D.{\sim}0.932\;mg/m^2$, total solvent content was $N.D.{\sim}2.433\;mg/m^2$.

• Journal of Korean Society of Environmental Engineers
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• 제37권5호
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• pp.293-302
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• 2015

Halonitromethanes (HNMs) are one of the most toxic groups of disinfection by-products. Recently, various studies have been fulfilled. An automated headspace-solid phase microextraction (SPME) gas chromatography/electron capture detector (GC-ECD) technique was developed for routine analysis of 9 HNMs in water samples. The optimization of the method is discussed. The limits of detection (LOD) and limits of quantification (LOQ) range from 90 ng/L to 260 ng/L and from 270 ng/L to 840 ng/L for 9 HNMs, respectively. Matrix effects in tap water and sea water were investigated and it was shown that the method is suitable for the analysis of trace levels of HNMs, in a wide range of waters. The method developed in the present study has the advantage of being rapid, simple and sensitive.

• Bulletin of the Korean Chemical Society
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• 제33권5호
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• pp.1693-1698
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• 2012

A headspace gas chromatographic mass spectrometric (GC-MS) assay method was developed for the simultaneous determination of methyl tertiary butyl ether (MTBE), $tert$-butyl alcohol (TBA) and benzene, toluene, ethyl benzene and xylene (BTEX) in soil contaminated with gasoline. 2 g of soil sample were placed in a 10 mL headspace vial filled with 5 mL of phosphoric acid solution (pH 3) saturated with NaCl, and the solution was spiked with fluorobenzene as an internal standard and sealed with a cap. The vial was heated in a heating block for 40 min at $80^{\circ}C$. The detection limits of the assay were 0.08-0.12 ${\mu}g$/kg for the analytes. For five independent determinations at 10 and 50 ${\mu}g$/kg, the relative standard deviations were less than 10%. The method was used to analyze fifty six soil samples collected from various regions contaminated with gasoline in Korea. The developed method may be valuable for the monitoring of the analytes in soil.

• Bulletin of the Korean Chemical Society
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• 제34권9호
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• pp.2691-2696
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• 2013

The electronic cigarette (E-cigarette) is a battery-powered device that aerosolizes nicotine so that it is readily delivered into the respiratory tract. The analytical data regarding the substances present in E-cigarettes are very limited. The aim of this study was to measure the concentration of aldehydes-formaldehyde (FA), acetaldehyde (AA) and, acrolein (AL)-in 225 replacement liquid brands from 17 E-cigarette shops sold in the Republic of Korea by headspace solid-phase micro extraction and gas chromatography-mass spectrometry (HS-SPME GC-MS). The concentration range of FA and AA was 0.02-10.09 mg/L (mean = 2.16 mg/L, detected in 207 of 225 samples) and 0.10-15.63 mg/L (mean = 4.98 mg/L, detected in all samples), respectively. AL was not detected in any of 225 replacement liquids. FA and AA were originally present in almost all replacement liquids of electronic cigarettes.

• Bulletin of the Korean Chemical Society
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• 제26권12호
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• pp.1996-2000
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• 2005

Headspace hanging drop liquid phase micro-extraction (HS-HD-LPME) is studied as a novel solvent-based sample pretreatment method for floral volatile aroma compounds. This paper reports on application of the HSHD- LPME combined with GC-MS for the analysis of linalool component emitted from evening primrose flowers. The effect of several variables on the method performance was investigated. Additionally, the separation of enantiomers on a cyclodextrin capillary column was performed to identify chirality of (−)-linalool component. Since the unsurpassed volume of a few micro-liters of solvent is used, there is minimal waste or exposure to toxic organic solvents. This method enables to combine extraction, enrichment, clean-up, and sample introduction into a single step prior to the chromatographic process.

• Analytical Science and Technology
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• 제7권1호
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• pp.125-132
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• 1994

Flavours in kimchee are the result of unique combination of various sugars, organic acids and amino acids as well as various volatile organic compounds including sulfur-containing compounds, terpenes, alcohols, and some volatile organic acids. In the experiment for the flavour extracting methods, dynamic headspace(DHS) is more effective for collection of volatile flavour than simultaneous distillation extraction(SDE). The best polarity available at the moment is 5% phenyl methyl poly-siloxane which will separate non-polar, intermediate and polar components with good resolution.

• Proceedings of the KIEE Conference
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.383-385
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• 2008

본 논문은 헤드스페이스 추출에 의한 절연유중 가스분석 결과의 정확도 향상을 위해 여러 가지 인자들을 고려하였으며, 진단결과의 신뢰도 향상을 위해 표준절연유를 직접 제조하여 이에 의한 교정을 통해 분석법의 진단 신뢰도 향상을 제고하였다. 기존의 추출율이 높은 토플러 추출방법에 대한 결과와 Headspace 분석법에 의한 결과를 각각 비교하고, Headspace 추출법에 의한 결과의 정확도 향상을 위해 여러가지 인자들을 고려하였다. 향후 최적 조건을 수립하여 수은에 의한 인체 유해성이 없는 Headspace 분석법으로의 전환을 모색하고자 한다.