• Korean Journal of Food Science and Technology
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• v.20 no.5
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• pp.732-735
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• 1988

Flavor stability of cooking oils such as rice bran oil, double fractionated palm olefin and soybean oil were determined by headspace analysis using gas chromatography. In the headspace, the contents of volatile compounds, oxygen and hydrogen were measured. The hydrogen content in the headspace correlated well with the contents of volatile compound (r > 0.95). Therefore, it is proposed that a single measurement of hydrogen and oxygen is used as a index of flavor stability of cooking oils instead of separate measurement of volatile compounds and oxygen. which have conventionally been used.

• Korean Journal of Food Science and Technology
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• v.17 no.5
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• pp.406-408
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• 1985

n-Hexanal in headspace over the cooked brown rice stored at $5^{\circ}C$ and $35^{\circ}C$ for 0. 4, 8 and 12 months was determined by a modified direct vapor injection gas chromatographic method. The retention time of n-hexanal was 3.5 min and n-hexanal could be rapidly separated from other compounds at the operational conditions of gas chromatography. n-Hexanal contents of cooked brown rice also showed a standard deviation of less than 10% of the average.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 1994.10a
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• pp.30-30
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• 1994

• Analytical Science and Technology
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• v.12 no.5
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• pp.1065-1077
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• 1999

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.366-367
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• 2003

암모니아 가스는 무색의 기체이지만 자극성이 크면서 부식성이 있고 수용액이 알칼리성인 대표적인 악취물질이다. 보통의 경우는 굴뚝 등에서 배출가스의 형태로 대량 방출되기도 하지만 자연상태에서도 여러 가지 생물학적 또는 화학적 반응 등을 통하여 생성되므로, 일상적인 생활 공간에서도 쉽게 검출될 수 있는 물질이다. 대기 중 암모니아의 농도는 기체상 시료를 직접 분석하는 가스 크로마토그래피와 시료를 액체상으로 변환시킨 후 암모늄 양이온의 농도를 분광광도법이나 중화적정법으로 측정한다. (중략)

• 월간산업보건
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• s.286
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• pp.25-34
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• 2012

• Proceedings of the Korean Fiber Society Conference
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• 1986.06a
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• pp.33-33
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• 1986

• Korean Journal of Food Science and Technology
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• v.17 no.5
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• pp.355-360
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• 1985

Soybean, hydrogenated soybean and corn oils, which were exposed to fluorescent light for different periods of time, were evaluated for sensory qualities by subjective sensory evaluation and instrumental gas chromatographic analysis. Sensory evaluation was conducted in 8 laboratories using a 10-point hedonic scale with a total of 95 panel members. The correlation coefficients between sensory scores and predicted sensory scores by gas chromatographic analysis for the 8 laboratories varied from 0.10 to 0.99. However, most laboratories had better than 0.90, which was considered excellent. The correlation coefficients between sensory scores of the 95 panel members and predicted sensory scores using the amount of 2. 4-decadienal isomers in oil determined by a gas chromatographic method for soybean, hydrogenated soybean, and corn oils, were r=0.96, r=0.97, and r=0.97, respectively. The correlation study suggests that it is possible to obtain realistic results of oil flavor qualities from the instrumental evaluation by combining improved gas chromatographic analysis, sensory evaluation, and statistical analysis for practical purposes.

• Applied Chemistry for Engineering
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• v.9 no.7
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• pp.985-989
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• 1998

In this study, removal efficiencies of pesticides on apples and peppers with water, dishwashing detergent, and alcoholic disinfectant were investigated by Gas Chromatography. Different conditions of pretreatment for increase of pesticide recovery were investigated for optimum condition. In our experiment, the supelco-STB-608 column and electron capture detector(ECD) were used to analyze pesticides residue. Removal efficiency of pesticide was in the order of alcoholic disinfectant>dishwashing detergent>water.

• Journal of the Korean Chemical Society
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• v.41 no.10
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• pp.524-534
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• 1997

Analysis of additives in cured rubber is often a difficult task for analytical chemists because of a wide variety of complex components. Conventional analyses of additives and rubbers have been done in multistep, off-line processes with large sample size and extensive sample preparations. The coumarone-indene resin, resorcinol-formaldehyde resin, and prevulcanization inhibitor have been characterized by their pyrolysis pathways and mass spectra of characteristic pyrolyzates. Pyrolysis Gas Chromatography/Mass Spectrometry (Py-GC/MS) was used in the identification of additives without any sample pretreatment. This result shows that several organic additives in cured rubber can be directly analyzed.