• Title/Summary/Keyword: GC-MS (SIM)

Search Result 318, Processing Time 0.04 seconds

SENSITIVE DETERMINATION OF ELEVEN PHENOLIC ENDOCRINE-DISRUPTING CHEMICALS IN HUMAN URINE USING GAS CHROMATOGRAPHY/MASS SPECTROMETRY -SELECTED ION MONITORING

  • Kim, Hyub;Jang, Cheol-Hyeon
    • Environmental Engineering Research
    • /
    • v.12 no.3
    • /
    • pp.93-100
    • /
    • 2007
  • I improved an analytical method for determining trace amounts of eleven phenolic endocrine-disrupting chemicals (11 phenolic EOCs) in human urine. The 11 phenolic EOCs were subjected to hydrolysis and then to solid phase extraction with a XAD-4 column. Alkylphenols, chlorophenols, and bisphenol A in XAD-4 column were eluted with acetonitrile, and the eluate was concentrated under a nitrogen stream, and then tert-butyldimethylsilylation. Separation and determination were done by gas chromatography, using mass spectrometry operating in the selective ion monitoring mode for quantitation. For tert-butyldimethylsily (TBDMS) derivatization the recoveries were $91.2{\sim}125.9%$, the limits of quantitation (LOQ) for the 11 phenolic EOCs in the nanogram-per-milliliter range ($0.025{\sim}1.000\;ng/mL$) were thus achieved by using 1 mL of urine, and the SIM responses were linear with the correlation coefficient varying by $0.9300{\sim}0.9943$. Based on the results for urine samples from unexposed individuals, 4-tert-octylphenol and pentachlorophenol were detected in hydrolysed urine sample. Other alkylphenols, chlorophenols and bisphenol A were not detected.

Simultaneous Analysis of Semi-Volatile Organic Base/Neutral Priority Pollutants in Soil (토양 중의 비휘발성 염기/중성 유기 Priority Pollutants 동시 분석에 관한 연구)

  • Lee, Seung Seok;Park, Gyo Beom;Lee, Seok Geun
    • Journal of the Korean Chemical Society
    • /
    • v.38 no.6
    • /
    • pp.418-426
    • /
    • 1994
  • This study was aimed at the detection of 40 semi-volatile organic base/neutral compounds from soil among 129 priority pollutants listed by EPA. Two extraction procedures, sonication extraction and Soxhlet extraction, were studied as a extraction and concentration method for priority pollutants in soil. Extracts were analyted by GC/MS-SIM(selected ion monitoring). The analytical methods were tested by standard compounds spiked into blank soil. Accuracy and precision of the methods were measured by calculation of mean recovery and mean relative standard deviation. And the method detection limits were estimated.

  • PDF

Simultaneous Analysis of Semi-Volatile Organic Acid Priority Pollutants in Soil (토양 중의 비휘발성 산성 유기 Priority Pollutants 동시분석에 관한 연구)

  • Lee, Seung Seok;Park, Gyo Beom;Lee, Seong Geun
    • Journal of the Korean Chemical Society
    • /
    • v.38 no.3
    • /
    • pp.246-253
    • /
    • 1994
  • The simultaneous analysis of 11 semi-volatile organic acid compound which are listed as priority pollutants by EPA, were performed by GC/MS-SIM(selected ion monitoring). Two extraction procedures, sonication extraction and Soxhlet extraction, were studied as an extraction and concentration method for priority pollutants in soil. Accurecy and precision of the methods were measured by the calculation of mean recovery, mean relative standard deviation, and method detection limit. Finally, limitations and prospects were discussed.

  • PDF

촉매에 따른 셀룰로오스로부터의 수소 발생량 변화

  • Gang, In-Cheol;Han, Jae-Gil;Zhang, Qiwu;Saito, Fumio
    • Proceedings of the Materials Research Society of Korea Conference
    • /
    • 2009.05a
    • /
    • pp.50.1-50.1
    • /
    • 2009
  • 셀룰로오스를 Ca(OH)2와 Ni(OH)2를 Pot에 넣고 동시에 밀링 공정을 실시한 후, 열을 가함으로써 수소를 얻었다. X-ray diffraction (XRD), thermogravimetry/ mass spectrometry (TG/MS), gas chromatography (GC) 장비를 이용해 수소 발생량 및 촉매의 역할에 관하여 실험하였다. 촉매 Ni(OH)2를 대신한 NiO 또는 Ni를 사용했을 경우 사용된 촉매에 따른 수소의 발생량의 차이를 보였는데 이는 촉매의 사이즈가 수소 발생량과 관련이 있음을 보여주었다. 한편, Ca(OH)2를 대신하여 Li(OH)를 사용하였을 때 수소 발생 온도가 약$400\sim500\;^{\circ}C$ 범위에서 $350\sim400\;^{\circ}C$의 범위로 낮아져 보다 낮은 온도에서 수소 회수가 가능하였다. 이때 발생한 CO와 CO2는 수 ppm정도로 적은 양이었다.

  • PDF

Major Chemical Constituents of Supercritical Carbon Dioxide Extract of Pandanus odorus Leaves

  • Rahman, N.N.Ab;Hassan, M.N.;Omar, A.;Kadir, M.O.Ab.
    • Natural Product Sciences
    • /
    • v.5 no.2
    • /
    • pp.75-79
    • /
    • 1999
  • Supercritical carbon dioxide was used as a solvent in the extraction of freeze-dried Pandanus odorus leaves. Analysis of the extract with GC-MS showed that Pandanus odorus leaves contain nutritional constituents such as ${\alpha}-tocopherol$ (Vitamin E) and squalene. The contents of ${\alpha}-tocopherol$ and squalene extracted from freeze-dried ground Pandanus odorus leaves at pressures ranging from 80 to $200\;kg\;cm^{-2}$ and temperatures between 40 to $80^{\circ}C$ were $134{\sim}300\;ppm$ and $750{\sim}1,200\;ppm$ respectively. The highest yield was obtained at $200\;kg\;cm^{-2}$ and $40^{\circ}C$. Other major components identified were hexadecanoic acid, 9,12,15-octadecatrien-1-ol, campesterol, stigmasterol and ${\beta}-sitosterol$.

  • PDF

Quantitative Comparison of Radiation-induced Hydrocarbons from Irradiated Beef, Pork and Chicken (쇠고기, 돼지고기, 닭고기로부터 방사선 조사에 의해 유도된 Hydrocarbon 류의 정량적 비교 분석)

  • Kim, Kyong-Su;Kim, Eun-Ah;Lee, Hae-Jung;Yang, Jae-Seung;Byun, Myung-Woo
    • Korean Journal of Food Science and Technology
    • /
    • v.31 no.2
    • /
    • pp.301-307
    • /
    • 1999
  • When fats are irradiated, hydrocarbons contained one or two fewer carbon atoms are formed from the parent fatty acids. A method to detect radiation-induced hydrocarbons consists of the extraction of fat from beef, pork and chicken, separation of hydrocarbons with a florisil column and identification of GC/MS methods. When beef, pork and chicken were irradiated, pentadecane, 1-tetradecene, heptadecane, 1-hexadecene, 8-heptadecene, 1,7-hexadecadiene, 6,9-heptadecadiene and 1,7,10-hexadecatriene were formed from palmitic, stearic, oleic and linoleic acids. Concentrations of the produced hydrocarbons tended to increase linearly with the dose levels of irradiation. Concentrations of hydrocarbons produced by ${\gamma}-irradiation$ depended upon the composition of fatty acids in beef, pork and chicken. The major hydrocarbons in irradiated beef, pork and chicken were 1,7-hexadecadiene and 8-heptadecene originating from oleic acid. 1,7-Hexadecadiene was the highest amount in irradiated beef, pork and chicken.

  • PDF

Volatile Flavor Components in Mash of Takju Prepared by Using Different Nuruks (누룩 종류를 달리하여 담금한 탁주 술덧의 휘발성 향기성분)

  • Han, Eun-Hey;Lee, Taik-Soo;Noh, Bong-Soo;Lee, Dong-Sun
    • Korean Journal of Food Science and Technology
    • /
    • v.29 no.3
    • /
    • pp.563-570
    • /
    • 1997
  • Volatile flavor components in the mash of takjus prepared by using different nuruks such as Mucor racemosus nuruk, Rhizopus japonicus nuruk, Aspergillus oryzae nuruk, Aspergillus kawachii nuruk and nuruk (Korean-style bran koji), were identified by using GC and GC-MS. Twenty alcohols, 26 esters, 10 acids, 10 aldehydes and 6 others were found in the mash of takju after 16 days of fermentation. Takju by Aspergillus oryzae nuruk had the most various components of volatile flavor. Fifty-four flavor components including ethanol, 2-methyl-1-propanol, 3-methyl-1-butanol, 1-hexanol, 2,3-butadienol (D,L), benzeneethanol, acetic acid ethyl ester, succinic acid diethyl ester, butanoic acid monoethyl ester, acetic acid and benzene acetic acid 4-acetyloxy-3-methyl ethyl ester were usually detected in all the treatments. The relative peak area of volatile components was as follows: alcohol $(71.28{\sim}90.23%)$, ester $(0.66{\sim}9.05%)$, acid $(0.2{\sim}0.6%)$ and aldehyde $(0.02{\sim}0.09%)$. Specially, 1-pentanol and hexanoic acid ethyl ester were high in takju made of nuruk (Korean-style bran koji). 1-Hexanol, 1-dodecanol, acetic acid and 1,2-benzene-dicarboxylic acid diprophenyl ester were high in takju made of Mucor racemosus nuruk. 4-Acetyloxy, 3-methyl benzeneacetic acid phenyl ester, 2-methyl-1-propanol, 3-methyl-1-butanol, succinic acid diethylester, butanoic acid monoethyl ester and butanoic acid were higher content in takju by Rhizopus japonicus nuruk. Acetic acid ethyl ester, pentanoic acid and 3-methyl butanoic acid were high in takju that was made of Aspergillus oryzae nuruk. 1-Butanol was high in takju by Aspergillus kawachii nuruk.

  • PDF

Studies on the Volatile Flavor Compounds of Sesame Oils with Roasting Temperature (볶음온도에 따른 참기름의 휘발성향기성분 변화)

  • Kim, Hyeon-Wee;Park, Ki-Moon;Choi, Chun-Un
    • Korean Journal of Food Science and Technology
    • /
    • v.32 no.2
    • /
    • pp.238-245
    • /
    • 2000
  • This study was investigated to compare the changes of flavors in sesame oil with roasting temperature $(110^{\circ}C{\sim}230^{\circ}C)$. In the results of analyzing the volatile flavor compounds of sesame oil with GC and GC/MS, 26 pyrazines, 11 pyridines, 9 thiazoles, 6 furans, 8 pyrroles, 5 phenols, 8 aldehydes, 8 hydrocarbons, 7 alcohols, 2 indoles, 3 ketones, 10 acids, 4 nitriles, 7 esters, and 5 others were isolated, identified, and quantified. The total amount of flavor compounds was increased with roasting temperature. Detected flavors could be devided into top(peak No. $1{\sim}91$), middle$(92{\sim}197)$ and last note$(198{\sim}224)$ by rentention time. The top notes(initial content 19.87 ppm) which contain pyrazines and provide representative roasted flavors were increased significantly with roasting temperature. Initial content of middle note(17.72 ppm) was increased to 36.71 ppm at $170^{\circ}C$, to 95.61 ppm at $220^{\circ}C$, and to 138.62 ppm at $230^{\circ}C$. Last note was almost unchanged up to $170^{\circ}C$ and increased at $190^{\circ}C$, whereas it indicated a tendency to decrease at $230^{\circ}C$. Pyrazines such as methylpyrazine, 2,5-dimethylpyrazine, 2,6-dimethylpyrazine, trimethylpyrazine, 2-ethyl-3,5-dimethylpyrazine which indicate the major components among volatile flavors were increased slightly up to $150^{\circ}C$ and revealed the higher increase than any other components above $170^{\circ}C$. This tendency was also similar to pyridines, thiazoles, and furans. Most of these compounds are assumed to be developed by thermochemical reactions of sesame components by roasting above $170^{\circ}C$. It seemed that a lot of increase in phenols above $210^{\circ}C$ resulted from the production of guaiacol. Acids were almost unchanged up to $190^{\circ}C$, increased at $210^{\circ}C$, and then decreased above $220^{\circ}C$. It seemed to be resulted from pyrolysis of free fatty acids formed from thermal oxidation of oil.

  • PDF

Characterization of Carbon Black and Oil from Positive Process of movable disc type for Waste Tires Pyrolysis (디스크 이동식 폐타이어 열분해 실증 설비로부터 생성된 Carbon Black, Oil의 특성 분석)

  • Ha, Hyun-Jung;Kim, Seong-Yeon;Kim, Ki-Kyeong
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2008.05a
    • /
    • pp.483-486
    • /
    • 2008
  • 본 연구에서는 디스크 이동식 열분해 실증 설비를 이용하여 폐타이어 열분해 반응을 수행하였고, 생성된 열분해 생성물들의 특성을 분석하였다. 폐타이어 열분해 반응은 약 $550^{\circ}C$에서 90분간 진행되었고, 반응 결과 Recovered Oil, Carbon Black, Non Condensing Gas(NC Gas)가 생성되었다. 폐타이어 열분해 생성물의 수율은 Recovered Oil $40{\sim}50%$, Carbon Black 30$\sim$35%, NC Gas 10$\sim$15%, Steel 10$\sim$15%로 나타났다. 폐타이어 열분해 반응 후 생성된 Recovered Oil은 비점 및 특성 분석 결과 상업용 중유와 비슷한 성질을 나타냈고, 폐타이어 열분해 반응의 또 다른 생성물인 Carbon Black은 특성 분석 결과 고정 탄소 비율이 낮은 반면 회분과 휘발분의 비율이 높아 상업용으로 사용하기 위해서는 적절한 정제 과정이 필요함을 알 수 있었다.열분해 과정 중에 생성된NC Gas는 GC/MS를 이용하여 성분 분석을 수행한 결과, $CO_2$, $CH_4$를 비롯하여 주로 탄화수소류로 이루어졌으며, 대부분이 연료 가스로 구성되어 있어 열분해 반응의 열원으로서 사용이 가능하였다.

  • PDF

Analysis of Fragrance Volatiles of Korean Rosa hybrida Using Gas Chromatography-Mass Spectrometry

  • Cho, Yong-Sik;Cho, In-Hee;Park, Hong-Ju;Chun, Hye-Kyung
    • Journal of Applied Biological Chemistry
    • /
    • v.49 no.4
    • /
    • pp.180-185
    • /
    • 2006
  • Two different extraction procedures, SDE and SPME, were employed to determine a comprehensive and efficient fragrance profile of Korean Rosa hybrida. Both extraction methods could compensate for each other, covering compounds with diverse boiling point, polarities, and chemical properties. A total of 46 compounds were identified in Mi-hyang. The identified compounds were composed of 17 alcohols, 14 carbonyls, 7 aliphatic hydrocarbons, 2 terpene hydrocarbons, 4 benzenes, 1 ester, and 1 miscellaneous compound. Quantitatively, carbonyls($12.96{\sim}21.79%$ in essential oils of SDE and $2.89{\sim}8.44%$ in SPME headspace) and alcohols($7.98{\sim}11.73%$ in essential oils of SDE and $3.39{\sim}17.35%$ in SPME headspace) were dominant in Mi-hyang's volatiles.