• 한국지하수토양환경학회지:지하수토양환경
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• 제6권3호
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• pp.73-91
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• 2001

미국지질조사소 NAWQA 프로그램에서 선정한 기준에 따라, 도시지역에서 채취한 도로를 흐르는 빗물과 일부 지하수의 휘발성유기화합물의 오염을 평가하기 위해 62개 휘발성유기화합물을 선택하였다. 62개 휘발성유기화합물은 3종류의 aromatic hydrocarbons, 13 종류의 alkyl benzenes, 1개의 ether, 26종류의 halogenated alkanes, 10종류의 halogenated alkenes 및 9종류의 halogenated aromatics를 포함하고 있다. 서울시 지역의 도로를 흐르는 빗물과 지하수의 휘발성유기화합물의 함량은 2000년 3월, 6월 및 11월에 시료를 채취하여 분석하였다. 모두 78개 시료(44개 도로를 흐르는 빗물시료, 27개 지하수 시료, 7개 하수종말처리장의 시료)가 채취되었으며, purge and trap 방법으로 추출하여 GC-MS로 분석하였다. 그 결과, alkyl benzenes과 aromatic hydrocarbons이 서울지역에서 자동차 통행에 의해 가장 영향을 받는 유기화합물이다. 분석된 62개 휘발성 유기화합물 중, 도로에 흐르는 빗물에서 검출되지 않은 휘발성유기화합물 성분은 단지 11개 성분뿐이었으나, 채취된 지하수에서 검출된 휘발성유기화합물은 14개 성분만이 검출되었다. 도로를 흐르는 빗물에서의 톨루엔 함량은 시료 채취 장소에 따라 변화가 매우 심하고, 0.1-29,310ppb이다. 벤젠의 함량은 0.05-33.0ppb, ethylbenzene은 0.05-960ppb, trichloromethane(chloroform)은 0.08-20ppb, trichloroethylene(TCE)는 0.03-4.30ppb, 1,1,2 trichloroethane은 0.1-50.0ppb이다. 채취된 일부 지하수 시료에 대한 예비조사 결과, dichloromethane(methylene chloride), trichloromethane(chloroform)와 toluene 등이 가장 자주 검출되는 성분이었다. 대부분의 aromatic hydrocarbons, alkyl benzenes및 다른 유기용매 성분은 검출농도 이하이다.

• 한국자동차공학회논문집
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• 제13권3호
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• pp.171-177
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• 2005

In order to investigate the effect of dimethyl ether (DME) on PAH and soot formation, the fuel has been mixed to the counter-flow diffusion flames of ethylene. Laser-induced incandescence and laser-induced fluorescence techniques were employed to measure relative concentrations of soot volume fraction and polycyclic aromatic hydrocarbon (PAH) concentration, respectively. Results showed that even though pure DME flame produces the minimal amount of PAH and soot, the mixture fuel of DME and ethylene could increase PAH and soot formation, as compared to those of pure ethylene flame. This implies that even though DME has been known to be a clean fuel for soot formation, the mixture fuel of DME and the hydrocarbon fuel could produce enhanced production of soot. Numerical simulation demonstrated that methyl (CH$_{3}$) radical generated by the initial pyrolysis of DME can be contributed to the enhancement of PAH and soot formation, through the formation of propargyl (C$_{3}$H$_{3}$) radical.

• 천문학논총
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• 제27권4호
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• pp.257-258
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• 2012

With AKARI, we carried out near-infrared spectroscopy of the nearby barred spiral galaxy, NGC 1097, categorized as Seyfert 1 with a circumnuclear starburst ring. Our observations mapped the galactic center region. As a result, we obtain the spatial distributions of the polycyclic aromatic hydrocarbon $3.3{\mu}m$ and the aliphatic hydrocarbon $3.4-3.6{\mu}m$ emission. The former is detected from all the observed regions and the latter is enhanced near the bar connecting the ring with the nucleus. In addition, we detect absorption features due to $H_2O$ ice and CO/SiO at the ring and the galactic center, while we detect the hydrogen recombination line $Br{\alpha}$ only from the ring. Hence the observed spectra change dramatically within the central 1 kpc region.

• Bulletin of the Korean Chemical Society
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• 제33권10호
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• pp.3241-3247
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• 2012

Ionic liquids (ILs) have been extensively investigated as promising alternatives to conventional organic solvents such as sulfolane and N,N-dimethylformamide for the selective extraction of aromatic hydrocarbons from the $C_6-C_{10}$ hydrocarbon mixtures produced from the cracking processes of naphtha and light oils. The most important advantage of ILs over conventional organic solvents is that they are immiscible with aliphatic hydrocarbons, and thus the back extraction of ILs from the raffinate phases and top hydrocarbon-rich layers is not necessary. In this paper, a brief review on the state of the art in the utilization of ILs for aromatics separation is presented.

• 한국환경과학회지
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• 제25권8호
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• pp.1177-1189
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• 2016

In order to prepare the information needed to construct a reduction system for volatile organic compounds (VOCs) exhausted from ship-block paint-booths in a giant shipyard, VOCs in paint-shop airs were analyzed and compared to the components in paint thinners. Aromatic hydrocarbons containing eight and nine carbon atoms are known to be major VOC compounds found in shipyard paint-shops. The total hydrocarbon (THC(C7)) concentrations calibrated using toluene gas, were measured in block paint-shops with two photo-ionization detector (PID) meters, and the resulting THC(C7) data were converted to THC(C1) concentrations according to the Standard Methods for the Measurements of Air Pollution in South Korea. THC(C1) concentrations near the spray site ranged from 10 to 2,000 ppm, but they were less than 400 ppm near the walls of the paint-booth. The measurements of THC concentrations, based on the height of the monitoring sites, were related to the height of the target to which the spray paints were applied. The maximum concentrations occurred at almost the same height as the spray targets. When painted blocks had been dried-by warming with no spraying, the THC concentrations were 80~100 ppm.

• Asian Journal of Atmospheric Environment
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• 제12권2호
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• pp.127-138
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• 2018

This study measured indoor and outdoor levels of hydrocarbon volatile organic compounds (VOCs), such as benzene, toluene, ethylbenzene, and xylene isomers (collectively referred to as BTEX), as well as 13 carbonyl compounds, at 20 homes in Seoul, South Korea. Along with the sampling of BTEX and carbonyls, indoor concentrations of the air pollutants nitrogen oxide (NO) and carbon dioxide ($CO_2$) were also measured at each home. These measurements were used to understand the characteristics of BTEX and carbonyls by calculating the various ratios and correlation coefficients between measured contaminant levels. We found that carbonyls were mostly originated from indoor sources, while BTEX were originated from both indoor and outdoor sources. A high correlation between indoor levels of NO and BTEX indicated that traffic emissions were also an important sources of BTEX.

• 한국산학기술학회논문지
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• 제6권3호
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• pp.255-260
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• 2005

PAHs는 2개 이상의 벤젠링을 가지는 방향족 탄화수소로, 특성과 분자량에 의해 크게 두 가지로 구분되며, 독성 유기물질들이 직$\cdot$간접적으로 인간에게 피해를 준다. 이러한 PAHs에 오염된 토양을 복구하기 위해서 PAHs를 완전분해 또는 무독성 화합물로 전환시켜야 한다. 본 연구에서는 PAHs분해를 위해 Bacillus subtilis을 사용하였고, 담체로 코르크분말과 톱밥을 선정하였다. Phenanthrene을 분해한 경우 코르크분말 담체와 톱밥담체가 비슷한 분해양상을 보였으며 , pyrene을 분해한 두 담체의 경우 톱밥 담체가 우수하다고 판명되었다. 또한 토양함수율은 분해제거효율의 주 영향요소로서 $45\~55\%$의 함수율 일 때 최적의 효율을 나타냈다.

• 천문학회보
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• 제44권2호
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• pp.44.3-44.3
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• 2019

Since the detection of 3.3-micron PAH (polycyclic aromatic hydrocarbon) and 3.4-micron aliphatic hydrocarbon features in the spectra of Titan (Bellucci et al. 2009; Kim et al. 2011) and Saturn (Kim et al. 2012), respectively, the 3.3-micron feature of gaseous CH4 has been thought to be still the important spectral feature in the 3-micron absorption structures of Titan and Saturn. However, the analyses of the 3.3-and 3.4-micron emission structures of Saturn revealed that the influence of the gaseous CH4 on the structures is rather minimal (Kim et al. 2019). We present synthetic spectra of gaseous CH4, and the PAH and aliphatic haze particles in order to show the degree of influence of their spectra on the 3.3-and 3.4-micron emission structures of Saturn, and we compare these synthetic spectra with currently available observations. We constructed these synthetic spectra using newly developed radiative transfer equations. These equations are able to address detailed radiative processes in the atmospheres containing various gases and haze particles. We expect these radiative transfer equations can also be widely applied to the investigation of radiative transfer processes and the analyses of the spectra of celestial objects such as the Earth, the Moon, planets, and interstellar nebulae.

• 한국환경성돌연변이발암원학회지
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• 제24권3호
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• pp.121-127
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• 2004

Cytochrome P4501B1(CYP1B1) is known to be inducible by xenobiotic compounds such as policyclic aromatic hydrocarbon(PAH) and dioxins such as 2,3,7,8-tetrachloro-dibenzo-p-dioxin(TCDD). And these induction of CYP1B1 is also regulated by many categories of chemicals. In order to investigate the effects of several chemicals on CYP1B1 gene expression in Hepa-I and MCF-7 cells, 5' flanking DNA of human CYP1B1 was cloned into pGL3 basic vector containing luciferase gene, and then transfected into these cells. After treatment of chemicals, the luciferase activity was measured. CYP1B1 enzyme metabolize PAHs and estradiol. CYP1B1 metabolize estradiol to 4-hydrozyestradiol that is considered as carcinogenic metabolite. Luciferase activity was induced about 20 folds over that control by 1 nM TCDD (2,3,7,8-tetrachloto-p-dioxin). Recent industrialized society, human has been widely been exposed to widespread environmental contaminants such as PAHs(polycyclic aromatic hydrocarbon) that are originated from the imcomplete combustion of hydrocarbons. PAHs are known to be ligands of the AhR(aryl hydrocarbon receptor). Induction of cytochrome P4501B1(CYP1B1) in cell culture is widely used as a biomarker for PAHs. Therefore we have studied the effect of PAHs in the human breast cancer cells MCF-7 to evaluate bioactivity of PAHs. We have used the United State of America EPA selected 13 different PAHs, PAHs mixtures and extracts from environmental samples to evaluate the bioassay system. We examined effects of PAHs on the CYP1B1-luciferase reporter gene and CYP1B1 mRNA level. Benzo(k)fluoranthene and dibenzo(a, h)anthracene showed strong response to CYP1B1 promoter activity stimulation, and also CYP1B1 mRNAs increase in MCF-7 cells in a concentration-dependent manner. Acenaphthene, anthracene, benzo(b)fluoranthene, fluorene, fluoranthene, anphthanlene, pyrene, phenanthrene and carbazole were weak responders in MCF-7 cells. RT-PCR analysis indicated that PAHs significantly up-regulate the level of CYP1B1 mRNA.

• 한국미생물·생명공학회지
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• 제35권4호
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• pp.261-271
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• 2007

토양오염을 복원하는 방법 중 식물상 복원은 식물을 이용하여 오염물을 제거하는 기술로, 환경 친화적이며, 경제적인 기술이기 때문에 많이 이용되고 있다. 이 연구에서는 식물상 복원에 있어 식물의 영향, 근권 세균과 물리화학적 제한인자에 대해 고찰하였다. 성공적인 식물상 복원을 위해서는 식물의 선택이 가장 중요하다. 유류(디젤) 분해를 위해 적용된 식물은 쥐보리(Lolium multiflorum lam), 베치(Vicia villosa), 버섯류(white mustard), 톨페스큐(Festuca arundinacea), 콩과식물(leguminosae), 포플러, 소나무(Pinus densiflora) 등이고, 유류 제거 효율은 68-99% 이었다. PAH(polycyclic aromatic hydrocarbons) 제거용으로는 옥수수(Zeo mays), 쥐보리, 베치, 버섯류, 토끼풀(Trifolium repens), 그리고 톨페스큐이 이용되었고, 50-98%의 제거 효율을 보였다. 식물의 성장을 향상시킬 뿐 만 아니라, 오염물질을 직접적으로 제거할 수 있는 근권 세균도 식물상 복원에 있어 중요한 역할을 한다. 식물상 복원에 이용된 근권 세균에는 Azospirillum lipoferum, Enterobactor cloacae, Azospirillum brasilense, Pseudomonas putida, Burkholderia xenovorans, Comamonas testosterone, Pseudomonas gladioli, Azotobacter chroococcu, Bacillus megaterium, Bacillus subtilis 등이 있다. pH, 온도, 영양물질, 최종전자수용체, 수분함량, 유기물 함량, 오염물질 종류와 물리화학적 인자도 식물상 복원에 있어 제한 요소로 작용한다.