• Title, Summary, Keyword: gas chromatography

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On the Pyrolysis of Polymers II. Identification of the Products from Polymer Pyrolysis by Gas Chromatography (高分子物質의 熱分解에 關한 硏究 (第2報) Gas Chromatography 에 依한 熱分解生成物의 檢索)

  • Chwa-Kyung Sung
    • Journal of the Korean Chemical Society
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    • v.7 no.2
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    • pp.106-114
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    • 1963
  • The products from polymer pyrolysis at $450^{\circ}$ are cooled with ice, then liquid and gaseous portions are analysed by gas chromatography. Di-2-ethyl hexyl sebacate column, silicone oil column, silica gel column and tetraethyleneglycol dimethylether column, which was most effective for the separation of hydrocarbon gases, are used. Identification of isomers could be secured more effectively by gas chromatography than mass spectrometry. Elucidation of the mechanism for thermal decomposition of polymers could be done through the identification of pyrolysis products. Although more extensive work is needed, some patterns of polymer pyrolysis are discussed.

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Multidimensional Gas Chromatography-A Powerful Tool for the Analysis of Multicomponent Mixtures

  • Kim, Kyoung-Su
    • Preventive Nutrition and Food Science
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    • v.1 no.1
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    • pp.127-133
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    • 1996
  • The development of high resolution capillary columns and a large variety of different detectors led to a strong position of gas chromatography in instrumental analysis. Every effort has been made to solve sophisticated separation problems by column switching. Nowadays, several systems are commercially available for this purpose. The principle and the capabilities of multidimensional gas chromatography(MDGC) are illustrated by different applications in the field of modern flavor and essential oil research.

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Simultaneous Gas Chromatographic Analysis of Ethanol and Acetic Acid in Vinegar (식초의 에탄올 및 초산 함량의 동시분석)

  • Yoon, Hee-Nam
    • Korean Journal of Food Science and Technology
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    • v.30 no.6
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    • pp.1247-1251
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    • 1998
  • A method is developed for simultaneously determining ethanol and acetic acid in vinegars by quantitative packed-column gas chromatography. Vinegars were filtrated and directly chromatographed on a $2\;m{\times}2\;mm$ stainless steel column packed with Tenax-GC, 80/100. Ethanol, isopropy alcohol as an internal standard, and acetic acid were completely separated within 20 min of running time without any interfering peaks. The accuracy of packed column gas solid chromatography (PCGSC) was discussed compared to the analytical data by titration, high performance liquid chromatography and capillary column gas liquid chromatography (CCGLC).

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The study on the analysis of α-naphthylamine in urine (요중 알파나프틸아민 분석에 관한 연구)

  • kim, Choon Sung;Roh, Jae Hoon;Bae, Mun Joo;Kim, Chi Nyon;Lim, Nam Gu;Won, Jong Uk
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.7 no.1
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    • pp.49-59
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    • 1997
  • This study was performed to analyze the purity of technical grade ${\alpha}$-naphthylamine, to establish optimal analytical condition of ${\alpha}$-naphthylamine in urine and to determine the urine sample of workers exposed to ${\alpha}$-naphthylamine. The purity of technical grade ${\alpha}$-naphthylamine were $96.5{\pm}2.38%$, $94.1{\pm}0.97%$, $97.0{\pm}0.02%$ by gas chromatography-mass selective detector. To analyze ${\alpha}$-naphthylamine in urine, high performance liquid chromatography-electrochemical detector and gas chromatography-electron capture detector operating conditions have been optimized by preliminary expriment. In high performance liquid chromatography-electrochemical detector, the mobile phase was consisted of acetonitrile(35%) and water(65%), and the flow rate was maintained at 1.0ml per minute. Optimal detective condition was 9.0V(10nA/V) of electrochemical detector. The recovery of sep-pak treatment method was highly estimated as pretreatment of ${\alpha}$-naphthylamine in urine. The free amine was isolated by gas chromatography-electron capture detector after basic hydrosis, sep-pak treatment, toluene elution and HFBA(heptafluoro-butyric anhydride) derivatization of urine. The recovery of ${\alpha}$-naphthylamine in urine was $98.73{\pm}3.29%$ by gas chromatography-electron capture detector. The sensitivity was more higher than that of high performance liquid chromatography-electrochemical detector. Urinary ${\alpha}$-naphthylamine was detected in only one worker among nine workers. The level of ${\alpha}$-naphthylamine in urine was 6.42 ng/ml.

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Enantioseparation of Flurbiprofen and Ketoprofen in Patches and in Urine Excretions by Achiral Gas Chromatography

  • Paik, Man-Jeong;Nguyen, Duc-Toan;Kim , Kyoung-Rae
    • Archives of Pharmacal Research
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    • v.27 no.12
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    • pp.1295-1301
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    • 2004
  • The enantiomeric composition tests on flurbiprofen and ketoprofen present in patch products and in urine excretions following patch applications were performed as diastereomeric (R)-(+)- 1-phenylethylamides by achiral gas chromatography and by gas chromatography-mass spectrometry in selected ion monitoring mode. The method for determination of (R)- and (S)-enantiomers in the range from 0.1 to 5.0 ${\mu}$g was linear (r ${\ge}$ 0.9996) with acceptable precision (% RSD ${\le}$5.2) and accuracy (% RE = 0.6 ~ -2.4). The enantiomeric compositions of flurbiprofen in one patch product and of ketoprofen in five different products were identified to be racemic with relatively good precision (${\le}$ 6.4%). The urinary excretion level of (R)-flurbiprofen was two times higher than its antipode, while the comparable excretion levels of (R)- and (S)-enantiomers for ketoprofen were observed.

Degassing of Aluminum and Aluminum Alloy Powders as Studied by Gas Chromatography

  • Watanabe, Ryuzo;Choi, Duk-Sun;Kawasaki, Akira
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • pp.716-717
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    • 2006
  • Gas release behavior from aluminum and Al 7075 alloy powders during heating in argon was investigated by in-situ gas chromatography. Water vapor, hydrogen, carbon mono-oxide were detected as individual evolution spectra against heating temperature and time. The mechanisms of water and hydrogen evolutions were studied in detail for the determination of effective degassing condition. Magnesium in the alloy powder was found to lower the hydrogen evolution temperature to enhance overall hydrogen release.

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Analysis of Nonstarch-polysaccharides in Some Korean Foods (일부(一部) 한국산식품(韓國産食品)의 비전분다당류(非澱粉多糖類) 분석(分析))

  • Kim, Eun-Hee;Maeng, Young-Sun;Woo, Soon-Ja
    • Korean Journal of Food Science and Technology
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    • v.25 no.4
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    • pp.299-306
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    • 1993
  • Determination of dietary fiber contents in some Korean foods was attempted by Englyst's gas chromatographic and colorimetric methods which measure the nonstarch polysaccharide (NSP) contents NSP values, except seaweeds, by gas chromatography (x) and colorimetry (y) were very closely correlated (y=1.01x-0.52, r=0.997, n=9), NSP values by gas chromatography were lower than total dietary fiber (TDF) Haloes by AOAC method. By adding lignin to NSP values, relation between the two methods was improved. But, TDF values (y) by adding lignin to NSP values and TDF values (x) by AOAC method were related as y=0.68x-0.64 and F=0.903(n= 12), which was not closely related.

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Determination of 3-Monochloro-1, 2-propanediol in Acid Hydrolyzed Soysauce(Ganjang) by Gas-Chromatography with Electron Capture Detector (Gas Chromatography-Electron Capture Detector를 이용한 산분해간장중의 3-Monochloro-1, 2-propanediol 분석법에 관한 연구)

  • 최종동;문귀임;오현숙;김동술
    • Journal of Food Hygiene and Safety
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    • v.16 no.1
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    • pp.61-65
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    • 2001
  • To investigate the optimum condition of 3-monochloro-1, 2-propanediol(MCPD) analysis, gas chromatography with electron capture detector was used. Determination of MCPD derivatized with phenylboric acid was more effective than that of underivatized MCPD. In derivatization of MCPD with phenyl boric acid, there were no significantly different between boiling for 2min at 9$0^{\circ}C$ and vortexing for 5min at room temperature. Extrelut column was suitable for extraction of MCPD diluted in 20% NaCl solution and recovery rates were higher than direct extraction of MCPD with ethyl acetate. But, the method of direct extraction of MCPD with ethyl acetate was useful for rapid ants qualitative analysis. The sample extracted in soysauce(ganjang) was derivatized with phenylboric acid and analyzed by gas chromatography-mass selective detector. That was confirmed as MCPD-phenylboronate.

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Effect of Discharge Gas on the Electrical Characteristics of the Glow Discharge Plasma for the Gas Chromatographic Detector (글로우방전 가스크로마토그라프 검출기에서 방전가스의 영향)

  • 박현미;강종성;김효진
    • YAKHAK HOEJI
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    • v.39 no.5
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    • pp.480-486
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    • 1995
  • The change in discharge current of a glow discharge has been shown the potential sensitive detector for gas chromatography. To investigate the effect of carrier gas on the electrical characteristics of the discharge and the peak response, the discharge pressure, gas flow rate, and discharge gap have been studied. The discharge gas included the Ar, He, and N$_{2}$. The gas flow rate has been found one of the important parameters to affect both the electrical characteristics and the peak response.

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