• 천문학논총
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• 제27권4호
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• pp.299-300
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• 2012

We investigate the relation between star formation activity and PAH $3.3{\mu}m$ emission. Our targets are mid-infrared-excess galaxies selected from the AKARI all-sky survey point source catalog. We performed AKARI near-infrared spectroscopy for them. As a result, we obtained $2.5-5{\mu}m$spectra of 79 galaxies, and selected 35 star-forming galaxies out of them. Comparing the PAH $3.3{\mu}m$ luminosities with the infrared luminosities, we find a linear correlation between them. However, by adding the results from literatures for luminous infrared galaxies and ultra-luminous infrared galaxies that are more luminous than our sample, the ratio of the PAH to the infrared luminosity is found to decrease towards the luminous end.

• 천문학논총
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• 제32권1호
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• pp.87-91
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• 2017

Polycyclic aromatic hydrocarbons (PAHs) are considered to be carriers of the unidentified infrared bands, which are ubiquitously observed in the Universe. PAHs are mainly formed around evolved carbon-rich stars and injected into interstellar space. Planetary nebulae (PNe), a late stage of low- and intermediate stellar mass evolution, are suitable objects to investigate the formation and evolution of PAHs. The shortest PAH feature is located in $3.3{\mu}m$, which is important to examine the excitation and size distribution of PAHs. While the number of samples had been limited before, the high sensitivity of AKARI /IRC has drastically increased the number of samples. We obtained the $2-5{\mu}m$ spectra of Galactic PNe with AKARI /IRC and compiled a near-infrared spectral catalog, containing 73 PNe. We investigate the detection rate and the evolution of the PAH features. The characteristics of the catalog are illustrated and the origin of the evolution of the PAH features is discussed.

• Asian Journal of Atmospheric Environment
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• 제10권2호
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• pp.90-98
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• 2016

Total suspended particulates (TSP) in the atmosphere were collected for 2 weeks during winter in Muroran, Hokkaido, Japan, a typical iron-manufacturing city. The concentrations of polycyclic aromatic hydrocarbons (PAHs) and nitropolycyclic aromatic hydrocarbons (NPAHs) in TSP were determined by high-performance liquid chromatography (HPLC) using fluorescence and chemiluminescence detectors, respectively. No relationship was observed between the atmospheric PAH and NPAH concentration, or the atmospheric PAH and TSP concentration. However, there was a tendency that the atmospheric PAH concentration was higher when the wind blew from the coke-oven plant. Furthermore, the concentration ratios of 1-nitropyrene to pyrene, which is a suitable indicator of the contribution made by automobiles and coal combustion systems to urban air particulates, were smaller in Muroran and the values were close to those observed in particulates from coal combustion systems. Therefore, these results show that the PAH and NPAH compositions for Muroran are characteristic of an iron-manufacturing city.

• 한국산학기술학회논문지
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• 제7권3호
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• pp.458-464
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• 2006

토양의 생물학적 복원은 산업화로 무차별하게 오염되어 있는 국내 산업단지 주변과 지하수 환경보전을 위한 경제적 도구로 인식되어왔다. 본 연구는 친환경적 생물복원을 위한 기초자료를 얻기 위하여 유류로 오염된 양토에서 Pseudomonas sp. (KCCM 40055)를 접종한 polyurethane 매체환경을 적용, 유류의 성분중 PAH 분해도를 조사하였다. 다공성 매체로서 재현성이 뛰어나며 미생물 부착에 활용되어 온 polyurethane foam을 사용하여 미생물 부착성을 아울러 조사하였다. 사용된 PU중 최저공극 foam인 SR9-35C/G 의 경우 부착률과 PAH분해율이 가장 높았으며 토양함수율 증가에 따라 그 효율이 증가하였다.

• Asian Journal of Atmospheric Environment
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• 제6권3호
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• pp.169-191
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• 2012

This review paper describes the ambient air PAH concentrations in different developing Asian countries, including China, Afghanistan, India, Malaysia, Turkey, Vietnam, Sri Lanka, Thailand and Cambodia. In this study, more than 75 research papers published in the English literature were reviewed with respect to the seasonal and locational concentrations of PAHs in each of 9 different Asian countries. This study compared, discussed and tabulated the PAH concentrations in developing Asian countries over a one decade (2000-2011) period. The PAH concentrations measured in developing countries highlights the necessity to improve the air quality in those countries. Compared to the developed nations in Asia, developing countries are almost one decade away from implementing environmental policies, such as Euro standards. This review discusses the reasons for the high PAH concentrations in developing nations particularly in China and India. Based on the literature available, some suggestions are made to reduce the concentrations of PAHs in the ambient air of developing nations. The total data obtained from the literature survey is tabulated and presented as supplementary information at the end of the manuscript.

• 대한의생명과학회지
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• 제10권4호
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• pp.341-346
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• 2004

Tumor necrosis factor-α (TNF-α) or its mRNA expression are increased in acute nephrosis of various types including ischemia/reperfusion injury. This study was undertaken to determine whether pentoxifylline (PTX), an inhibitor of TNF-α production, provides a protective effect against hypoxia-induced cell injury in rabbit renal cortical slices. To induce hypoxia-induced cell injury, renal cortical slices were exposed to 100% N₂ atmosphere. Control slices were exposed to 100% O₂ atmosphere. The cell injury was estimated by measuring lactate dehydrogenase (LDH) release and p-aminohippurate (PAH) uptake. Exposure of slices to hypoxia increased the LDH release in a time-dependent manner. However, when slices were exposed to hypoxia in the presence of PTX, the LDH release was decreased. The protective effect of PTX was dose-dependent over the concentrations of 0.05∼1 mM. Hypoxia did not increase lipid peroxidation, whereas an organic hydroperoxide t-butylhydroperoxide (tBHP) resulted in a significant increase in lipid peroxidation. PTX did not affect tBHP-induced lipid peroxidation. Hypoxia decreased PAH uptake, which was significantly attenuated by PTX and glycine. tBHP-induced inhibition of PAH uptake was not altered by PTX, although it was prevented by antioxidant deferoxarnine. The PAH uptake by slices in rabbits with ischemic acute renal failure was prevented by PTX pretreatment. These results suggest that PTX may exert a protective effect against hypoxia-induced cell injury and its effect may due to inhibition of the TNF-α production, but not by its antioxidant action.

• 한국지하수토양환경학회지:지하수토양환경
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• 제22권2호
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• pp.26-32
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• 2017

Regression analyses were conducted for prediction of benzo(a)pyrene (BaP) and total polycyclic aromatic hydrocarbons (PAHs) in soils. Dimensionless units were applied after each PAH was divided by naphthalene (Nap) for the regression analyses using a previously published Swiss data set or all data sets, including Chinese and Brazilian. A strong correlation was found between BaP/Nap ($R^2=0.95$) or ${\Sigma}PAH/Nap$ ($R^2=0.99$) and Pyr/Nap ratios from the Swiss data set. When the developed prediction equation was applied to other measurements to validate its accuracy, there was great agreement between the data and predicted values. This model could be used as a useful tool for the calculation of average BaP and ΣPAH in specific regions without additional tests.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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• pp.415-418
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• 2006

회동저수지를 중심으로 수영강 일대 하상퇴적물에 대한 PAHs(Polycyclic Aromatic Hydrocarbons) 오염특성 연구가 진행되었다. 하상퇴적물의 화학분석결과, 16 EPA PAHs 중 naphthalene 등 총 15개 성분이 검출되었으며, benzo(a)anthracene과 chrysene의 검출빈도가 가장 높고, 총 PAHs는 최대 7,116 ppb가 검출되었다. 한편 퇴적물 내 PAHs의 심도별 함량 변화는, 대체로 하부 시료에 비해 상부 시료에 PAHs 함량이 높게 나타나며, 특히 상부의 점토질 토양과 하부의 현지 토양이 함께 산출되는 시료의 경우, 하부 현지 토양에서의 PAHs 함량에 비해 상부 점토질 토양에서의 PAHs 함량이 높으며, 이는 PAHs가 수영강 으로부터 유입되어 주로 상부 점토질 퇴적물에 축적된 결과로 판단된다. PAHs의 기원은 전반적으로 수영강 상류지역에서는 연소 기원을 보이며, 수영강 하류에서는 교량 및 도심지역에서의 차량통행과 관련이 있는 석유류의 특징을 나타내며, 회동저수지의 경우 석유류와 연소 기원의 특징을 복합적으로 보여주고 있다.

• 미생물학회지
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• 제37권2호
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• pp.120-123
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• 2001

Sphingomonas chungbukensis DJ77에서 난분해성 물질 분해 유전자가 chromosome 또는 plasmid 존재하는지를 규명하였다. 야생주 DJ77의 plasmid를 mitomycin C를 이용하여 curing 시킨 후, 각각 phenanthrene과 biphenyl이 단일 탄소원으로 첨가된 최소배지에서 배양한 결과 야생주는 성장을 하지만 plasmid가 제거된 DJ77은 성장하지 않았다. 각각의 plasmid DNA를 분리한 수 이미 클로닝된 방향족 탄화수소 분해에 관련된 DNA를 probe로 하여 Southern hybridization을 한 결과 야생주에서만 positive signal을 발견할 수 있었다.

• Journal of Korean Society for Atmospheric Environment
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• 제19권E2호
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• pp.89-97
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• 2003

Ambient polycyclic aromatic hydrocarbons (PAHs) were measured during the winter and summer of 2002 in Chongju. A filter pack and polyurethane foam (PUF) system was employed to collect simultaneously the particulate and gas phase PAHs. The samples were then analyzed using a gas chromatograph equipped with mass spectrometer detectors (GC/MSD). A total of 29 samples were collected and 11 PAH species were identified. The lower molecular weight PAH compounds (3∼4 rings) dominated the total PAH mass. The higher molecular weight PAH compounds (5∼6 rings) were less abundant. The PAHs were showed to exhibit seasonal variations. The concentrations of all com-pounds were significantly higher in winter than summer. The lower molecular weight PAHs were mostly found in the gas phase whereas the heavier ones were mainly associated with particulate phase. Vehicle emissions are likely to be the primary contributor of PAHs in Chongju. This study also demonstrated that it is necessary to perform simultaneously particulate and gas phase measurements to determine the accurate concentrations of ambient PAHs.