• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2000.11a
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• pp.377-383
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• 2000

급속한 경제 성장에 따른 산업구조의 고도화 및 다양화로 인하여 유기용제는 많은 사업장에서 널리 사용되는 물질의 하나로 종류도 매우 다양해져 400여종 이상이 되며/sup 1)/, 사용량도 매년 10%이상 증가하고 있어 근로자에게 직접 또는 간접적으로 폭로되어 건강에 나쁜 영향을 초래하고 있다. 유기용제에 의한 건강 장해를 예방하기 위해서는 유기용제의 사용 실태파악과 정확한 작업환경측정 및 평가를 통한 작업환경관리가 산업위생학적 견지에서 매우 중요하다고 생각할 수 있다/sup 2)/.(중략)

• Analytical Science and Technology
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• v.19 no.6
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• pp.553-558
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• 2006

In this study, an attempt was made to measure uncertainties involved in the VOC analysis for the VOC working standards prepared by a dilution technique using Tedlar bags. For this purpose, VOC standard gases of benzene, toluene, xylene, and styrene were prepared at four different concentrations (4, 8, 20, and 40 ppb). These standard samples were then loaded on to the GC system equipped with air server/thermal desorption (AS/TD) system. Each of these four standard concentrations was analyzed individually to derive their respective calibration results. These calibration data sets were then compared across four different compounds. According to this comparison, differences in calibration patterns were moderately insignificant within the selected concentration range of 4~40 ppb. It was also observed that the loss of styrene standard was fairly high compared to other VOCs investigated simultaneously. The results of our study suggest that the analytical uncertainty associated with the preparation of VOC starndard gas using a dilution technique can be assessed in a fairly reasonable manner for samples with a narrow concentration range.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2007.10a
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• pp.106-108
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• 2007

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2010.04a
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• pp.319-321
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• 2010

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2016.10a
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• pp.323-324
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• 2016

• Applied Chemistry for Engineering
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• v.5 no.1
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• pp.1-15
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• 1994

Temperature-programmed desorption method is a very useful technique for the research of heterogeneous catalysts. In most cases, the experimental condition is atmospheric. However, recently TPD experiments under vacuum conditions using powder catalysts give lots of very important results that can't be obtained otherwise. In this paper, the interpretation method of TPD results and the experimental technique under vacuum conditions are introduced briefly.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2005.11a
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• pp.405-406
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• 2005

• 월간산업보건
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• s.290
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• pp.27-37
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• 2012

• Analytical Science and Technology
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• v.15 no.1
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• pp.80-86
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• 2002

The simultaneous analysis of the odorous compounds designated by law in Korea and Japan was examined with the thermal desorber gas chromatography-mass spectrometry using one column. The approximate concentrations of trimethyl amine, acetaldehyde, methyl mercaptan and dimethyl sulfide were estimated. Styrene, dimethyl disulfide, propionaldehyde, n-butyl aldehyde, i-butyl aldehyde, n-valeraldehyde, i-valeraldehyde, ethyl acetate, toluene, xylene, methyl i-butyl ketone and i-butanol were detected at concentrations of the detection limits of their threshold values. As a typical example of simultaneous analysis of the odorous compounds, the volatile organic compounds emitted from compost procedure of food waste were concentrated and analyzed with thermal desorber/GC/MSD, and major malodorous compounds were estimated from the concentrations and threshold values of the detected components. From the result of analysis, 34 compounds were confirmed and among them, trimethyl amine, i-valeraldehyde, methyl mercaptan, methyl allyl sulfide, dimethyl sulfide, acetaldehyde, ethanol, n-butyaldehyde were expected to attribute to the odor in order of strength.

• Analytical Science and Technology
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• v.23 no.1
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• pp.24-35
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• 2010

To learn more about the calibration properties of reduced sulfur compounds (RSCs) by the combination of gas chromatography(GC)-pulsed flame photometric detector (PFPD) and thermal desorption method, a series of calibration experiments were conducted on the basis of both internal and external calibration approaches. For these experiments, gaseous standards of 4 RSCs ($H_2S$, $CH_3SH$, DMS, and DMDS) were prepared at two different concentration levels of both low (10, 20, 50,and 100 ppb) and high ranges (100, 200, 500, and 1000 ppb) along with $CS_2$ as an internal standard. First, the external calibration results were compared between fixed standard volume (FSV) and fixed standard concentration (FSC) method. Secondly, FSV-based calibration results were compared between external and internal calibration results. As FSV method suffers from sensitivity variations less significantly than FSC, the former is recommended to maintain the consistency in GC-TD sensitivity for RSC analysis. In addition, when the calibration data were examined in terms of RSE between external and internal calibration data, the results were not consistent enough to show improvements in internal method. Hence, diverse efforts are desirable to optimize the reproducibility in terms of GC-TD sensitivity for RSC analysis.