• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
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• pp.370-375
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• 2004

KMnO$_4$에 의한 TCE 용액의 분해에서 Headspace를 가진 반응 용기는 liquid sample을 headspce의 관측값으로 반응의 특성을 나타낼 수 없다. 이런 특성에 의해 in-situ KMnO$_4$ 이용은 TCE의 제거 효율에서 자연적인 휘발을 고려해야한다. 1:2.45 몰비에서 liquid sample의 결과 반감기는 약 80분이고 160분에 약 67%의 제거율을 보인다. 1:12.27 몰비의 경우 반감기는 10분이고 90분에 95%의 제거효율을 보인다.

• Bulletin of the Korean Chemical Society
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• 제27권2호
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• pp.231-236
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• 2006

A novel sample pretreatment technique, headspace hanging drop liquid phase microextraction (HS-LPME) was studied and applied to the determination of flavors from solid clove buds by gas chromatography-mass spectrometry (GC-MS). Several parameters affecting on HS-LPME such as organic solvent drop volume, extraction time, extraction temperature and phase ratio were investigated. 1-Octanol was selected as the extracting solvent, drop size was fixed to 0.6 $\mu$L. 60 min extraction time at 25 ${^{\circ}C}$ was chosen. HS-LPME has the good efficiency demonstrated by the higher partition equilibrium constant ($K_{lh}$) values and concentration factor (CF) values. The limits of detection (LOD) were 1.5-3.2 ng. The amounts of eugenol, $\beta$-caryophyllene and eugenol acetate from the clove bud sample were 1.90 mg/g, 1.47 mg/g and 7.0 mg/g, respectively. This hanging drop based method is a simple, fast and easy sample enrichment technique using minimal solvent. HSLPME is an alternative sample preparation method for the analysis of volatile aroma compounds by GC-MS.

• 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.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.2
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• pp.265-270
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• 2006

This paper reports an improved headspace gas chromatographic method for the determination of carboxyl group content in wood fibers. Pretreatment of wood fibers was applied using dilute HCl to convert carboxyl groups to carboxylic acid groups and then using deionized water to wash fiber samples thoroughly. The samples were finally air dried. Sodium bicarbonate solution was used to react with carboxylic acid groups of the pretreated fibers in a closed testing vial to release carbon dioxide. The content of carboxyl groups in fibers was accurately quantified by determining the amount of carbon dioxide released by a headspace gas chromatograph equipped with a thermal conductivity detector. The modified process for fiber sample pretreatment increased the reliability and accuracy in measuring carboxylic acid groups. The present method is simple, accurate.

• 한국식품영양학회지
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• 제17권2호
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• pp.220-228
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• 2004

Tenax-TA와 동적 headspace 향 포집방법을 이용하여 볶음들기름의 향기성분을 농축하였다. 이때 반응표면분석법을 이용하여 Tenax-TA에 결합한 향기성분의 탈착에 의한 손실을 최소화하고 휘발성이 낮은 화합물의 포집 효율을 극대화시키는 최적조건을 결정하였다. 독립변수로 향 포집 온도와 시간 및 시료량을 설정하였고 총 peak 면적, 탈착율, 휘발성이 가장 낮은 화합물인 perilla ketone의 면적을 종속변수로 하였다. 등고선 그림을 겹친 결과 0.6 g의 볶음들기름을 48$^{\circ}C$에서 12분 동안 포집시키는 것이 최적조건이었으며 Tenax-TA에서 탈착되는 주요한 휘발성 화합물은 2-propanone, 2-butanone, acetic acid 및 2-methyl propanal이었다.

• Bulletin of the Korean Chemical Society
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• 제27권2호
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• pp.302-304
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• 2006

• 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.

• Preventive Nutrition and Food Science
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• 제8권4호
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• pp.315-320
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• 2003

Headspace volatile compounds of oxidized fish oil were analyzed by the combination of hexane solvent or solid phase microextraction, gas chromatography and mass selective detector. The optimum condition of headspace analysis by hexane trapping was 23 min absorption time, 96$^{\circ}C$ sample temperature and 20 mL/min air flow rate. The numbers of volatile compounds identified by solvent trapping and SPME were 35 and 14, respectively. Groups having the largest amount and many kinds were hydrocarbons and aldehydes, respectively. The numbers of aldehydes were 15 and 6 for solvent trap and SPME, respectively. These basic data could be used as indicators for the quality changes of fish oil.

• 분석과학
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• 제27권1호
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• pp.22-26
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• 2014

1,4-dioxane은 국제 암연구소에서 2B의 발암물질로 분류하고 있는 물질이다.지표수 중에 1,4-dioxane을 headspace gas chromatographic mass spectrometry에 의해 측정하였다. 시료 5 mL를 10 mL 헤드스페이스 vial에서 넣고 NaCl로 포화시킨 후 내부표준물질로 1,4-dioxane-d8 첨가한 후 $90^{\circ}C$에서 30분간 가열하였다. 위의 방법을 사용하여 금강 22개 지점에서 2012년 6월과 9월 시료 채취하여 분석한 결과 $0.49-43.0{\mu}g/L$ (평균 $2.0{\mu}g/L$)의 범위로 약 30%의 빈도로 검출되었다.

• 한국식품위생안전성학회지
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• 제22권4호
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• pp.243-247
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• 2007

헤드스페이스-기체크로마토그래프/질량분석기를 이용하여 음료류 중 벤젠을 분석하였다. 대상식품은 시중에 유통되는 과실쥬스 2종, 과실음료 6종, 착향탄산음료 11종, 혼합음료 55종, 추출음료 7종, 음료베이스 4종 등 총 85종이었다. 헤드스페이스의 상평형을 위하여 $40^{\circ}C$에서 30분간 교반하였으며 오븐온도는 초기 온도 $60^{\circ}C$에서 5분간 유지 후 $15^{\circ}C$/분의 비율로 $180^{\circ}C$까지 상승하였다. 내부표준물질로는 벤젠-d6을 사용하였다. 선택이온 m/z 51, 77, 78로 확인하였으며 선택이온 m/z 78에 대한 m/z 77의 반응세기비로 재검증하였다. 벤젠의 선택이온 m/z 78과 내부표준물질 벤젠-d6의 선택이온 m/z 84에 대한 피크 면적비로 정량하였다. 회수율은 $91{\sim}101%$이었으며, 정량한계는 $1{\mu}g/kg$이었다. 벤젠의 평균검출수준은 과실음료의 경우 $5{\mu}g/kg$, 착향탄산음료의 경우 $2{\mu}g/kg$, 혼합음료의 경우 $7{\mu}g/kg$, 추출음료의 경우 $7{\mu}g/kg$이었다.