• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 총회 및 춘계학술발표회
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• pp.232-236
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• 2005

In-situ Air Sparging (IAS, AS) is a groundwater remediation technique, in which organic contaminants are volatilized into air as it rises from saturated to vadose soil zone. The purpose of this study was to investigate the effect of environmental conditions on the degradation of VOCs (Volatile Organic Compounds) and $CO_2$ in the unsaturated zone and TPH (Total Petroleum Hydrocarbons) in saturated zone of sandy loam. In the laboratory, diesel (10,000 mg TPH/kg)-contaminated saturated soil. After heating the soil for 36 days, the equilibrium temperature of soil reached to $34.9{\pm}2.7^{\circ}C$ and TPH concentration was reduced to 78.9% of the initial value, Volatilization loss of VOCs in TPH was about 2%, The reduction gradient of $CO_2$ concentration was 0.018/day in air space and 0.0007/day in unsaturated zone.

• 한국대기환경학회지
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• 제14권5호
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• pp.507-518
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• 1998

A field comparison study was carried out to quantify differences among various sampling and analytical methods for volatile organic compounds (VOCs) at a site in Vlsan in June 1997. Air sampling containers (SUMMA canisters) were used by the Korea Institute of Science and Technology (KIST) and adsorption tubes (carbotrap) were used by Yeungnam University (YN Univ.) for sampling ambient air. Duplicate samples obtained by KIST were analyzed by KIST with a GC-MS system for aromatics and halogenated hydrocarbons and by Atm AA with a GC -FID system for C2∼C9 hydrocarbons, respectively. The adsorption tube samples were analyzed by YN Univ. with a GC-FID system for aromatics. VOC levels for the duplicate canister sampls analyzed by KIST and Atm AA were in good agreement. Concentrations of aromatics by the adsroption tube method were generally higher than those by the canister sampling method by factor of 1.5 to 2.0. Differences between the two sampling methods were discussed.

• Applied Biological Chemistry
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• 제34권4호
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• pp.366-372
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• 1991

관행법에 의해 재배된 수세미외의 잎, 줄기, 미숙과즙, 종실, 수액 등 각 부위에 함유된 휘발성 정유성분, 탄화수소, 유기산 및 비휘발성 지방산을 추출, 분리하였다. 150여개의 분리성분중 37개 정유 성분을 확인한 후 각 부위별로 정량하였다. 또한, 26종의 탄화수소, 5종의 유기산 및 6종의 지방산도 분리정량하여 부위별 분포와 함량을 비교하였다.

• 한국대기환경학회지
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• 제19권4호
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• pp.363-376
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• 2003

In this study, the fugitive emission characteristics of airborne volatile organic compounds from different source categories were evaluated with respect to the concentrations measured in the vicinity of the sources. A total of 22 different sources were investigated, including gasoline storage and filling stations, painting spray booth, laundry, printing officer, textile industries, and a number of environmental sanitary facilities such as landfill, wastewater treatment and incineration plants. The target VOCs included 83 individual compounds, which were determined by adsorption sampling and thermal desorption coupled with GC/MS analysis. Overall, the aliphatic compounds appeared to be the most abundant class of compounds in terms of their concentrations, followed by aromatic, and halogenated hydrocarbons. As a single compound, however, toluene was the most abundant one, explaining 11% of the total VOC concentrations as an average of all the dataset. Among source categories, petroleum associated sources such as gasoline storage/filling stations, and laundry factory were identified as the most significant sources of aliphatic hydrocarbons, while aromatic VOCs were dominantly emitted from the sources handling organic solvents, such as painting booth, printing offices, and textile dyeing processes. However. there was no apparent pattern in terms of the contributions of eath group to the total VOCs concentrations in environmental sanitary facilities. It was also found that the activated carbon adsorption tower installed for the VOC emission control in some facilities do not show any effective performances, which may result in the increased VOC levels in the ambient atmosphere.

• 한국대기환경학회지
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• 제17권3호
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• pp.233-240
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• 2001

The composition of volatile organic compounds (VOCs) was anlyzed for major emission sources such as vehicle exhaust, gasoline and diesel vapor, organic solvent vapor, and butane fuel gas. Low carbon-numbered hydrocarbons were found to be the dominant components of gasoline vehicle exhaust. In gasoline evaporative vapor, the predominant constituents were found to be butane and iso-pentane regardless of ambient air temperature. In case of diesel evaporative vapor was similar to those of gasoline evaporative vapor. The composition of organic solvent vapor from painting, ink and petroleum consisted mostly or aromatic compounds such as toluene and m, p, o-xylene. The hydrocarbon fraction of butane fuel gas. which is used by portable bunner, consisted mainly of propane (34%) and butane(70%).

• 한국환경과학회지
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• 제3권4호
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• pp.373-380
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• 1994

Volatile organic compounds in the ambient air were gathered irregularly by normal temperature concentrating method at Odea-ri and Oceon-ri Ulsan-gun in the neighbourhood of Ulsan Petrochemical Industrial Complex and analyzed with gas chromatograph. Several hydrocarbons in common aklospheric air or emitted fugitively from the chemical plants were identified and quantified by comparison with the retention times of standard compounds. The results from several field surveys in 1992 show that the concentrations of styrene at residential area of Odea-ri and Ocheon-ri were less than 0.4 ppm, but once a while greater within the chemical plants area. When it smelled unpleasantly in these area, the concentration of hydrocarbons were also high. It was concluded that the close and long-term investigation about other odorous components but hydrocarbons will be necessary to ascertain the cause of unpleasant odor of these area.

• 한국식품저장유통학회지
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• 제31권3호
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• pp.374-384
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• 2024

Soybean paste is a staple food used to make doenjang (DE), cheonggukjang (CGJ), and miso (MI). In this study, solid-phase microextraction followed by gas chromatography-mass spectrometry was used to identify volatile components in DE, CGJ, and MI, and principal component analysis (PCA) was performed to determine their correlation between soybean pastes. Esters and hydrocarbons accounted for more than 55% of the total volatile components. PCA showed that esters were highly correlated with DE; pyrazines were correlated with CGJ; and alcohols were highly correlated with MI. Because DE, CGJ, and MI are made of the same material, their overall volatile content tended to be similar. However, the main volatile components and fragrances were different. These findings will be used as basic research data to promote quality improvement of soybean-based fermented foods in Korea and Japan.

• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2005년도 국제학술대회
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• pp.333-336
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• 2005

32 Volatile organic compounds(VOCs) were measured by thermal desorption/gas chrornatography/mass spectrometry in normal houses, new and sick houses. The sum concentrations of aromatic hydrocarbons in living room of new and sick houses showed 606 ${\mu}g/m^3$ and 645 ${\mu}g/m^3$, respectively, These figures were about 40 times higher than the values 14 ${\mu}g/m^3$ in normal houses. Among the chlorinated hydrocarbons trichloroethylene in the new and sick houses were at least 50-100 times higher than the mean concentrations in normal houses. But no significant differences could be shown for the concentration of VOCs in indoor air between new houses and sick houses (p<0.05).

• 한국분무공학회지
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• 제24권1호
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• pp.21-26
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• 2019

In Korea, Medium-duty trucks are classified into GVW (Gross Vehicle Weight) 3.5~10tons. MDTs are mostly used for logistics or delivery between regions. There have been studied on diesel fuel vehicles for SUVs(Sports Utility Vehicle) or light-duty trucks. But MDTs have been not studied. Therefore, this study have been used MDTs for characteristic exhaust emission. Test was carried out using the certification test mode (NEDC, New European Driving cycle) and the NIER mode in chassis dynamometer of the MDTs. And emission gas was analyzed for PN (Particulate Number), PN size distribution and aldehydes, VOCs (Volatile Organic Compounds), PAHs (Polycyclic Aromatic Hydrocarbons). This paper concluded that EURO-IV trucks produced more MSATs than EURO V trucks. Depending on the engine temperature, more MSATs were generated in cold temperature than in the hot start operation. However, the driving speed, the opposite results was obtained.

• Environmental Analysis Health and Toxicology
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• 제27권
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• pp.12.1-12.8
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• 2012

Objectives: The aim of this study was to identify the health and environmental risk factors of air contaminants that influence environmental and respiratory diseases in Gyeongju, Pohang and Ulsan in South Korea, with a focus on volatile organic compounds (VOCs). Methods: Samples were collected by instantaneous negative pressure by opening the injection valve in the canister at a fixed height of 1 to 1.5 m. The sample that was condensed in $-150^{\circ}C$ was heated to $180^{\circ}C$ in sample pre-concentration trap using a 6-port switching valve and it was injected to a gas chromatography column. The injection quantity of samples was precisely controlled using an electronic flow controller equipped in the gas chromatography-mass spectrometer. Results: The quantity of the VOC emissions in the industrial area was 1.5 to 2 times higher than that in the non-industrial area. With regards to the aromatic hydrocarbons, toluene was detected at the highest level of 22.01 ppb in Ulsan, and chloroform was the halogenated hydrocarbons with the highest level of 10.19 ppb in Pohang. The emission of toluene was shown to be very important, as it accounted for more than 30% of the total aromatic hydrocarbon concentration. Conclusions: It was considered that benzene in terms of the cancer-causing grade standard, toluene in terms of the emission quantity, and chloroform and styrene in terms of their grades and emission quantities should be selected for priority measurement substances.