• Journal of Korean Society for Atmospheric Environment
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• v.20 no.E2
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• pp.53-59
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• 2004

The roadway tunnels in urban areas give rise to problems such as a localized air pollution. Here, we report the results of a case study of an urban roadway tunnel measurement. The size-resolved particle sampling was carried out with a two 2-stage filter pack samplers and an Andersen impactor sampler at the center of Buk-Ak tunnel in November 2001. Particle Induced X-ray Emission (PIXE) was applied to determine the elemental composition of size-resolved particles divided into soluble and insoluble fractions. The Thermal/Optical Reflectance (TOR$^{(R)}$) method was also employed in analyzing of elemental carbon (EC) and organic carbon (OC). Mass concentrations of fine (< 1.2 ${\mu}{\textrm}{m}$) and coarse (> 1.2 ${\mu}{\textrm}{m}$) particles are 165 and 48 $\mu\textrm{g}$ m$^{-3}$ , respectively. Total elemental mass concentration (the sum of insoluble coarse, soluble coarse, insoluble fine, and soluble fine) is found to be 24$\mu\textrm{g}$ m$^{-3}$ and comprises only 11 % of total particle mass concentration. The concentrations of EC, OC, and mass show the clear dependency on particle size with the maximum between 0.1 and 0.43 ${\mu}{\textrm}{m}$ aerodynamic diameters. Total carbon (sum of EC and OC) accounts for approximately 70% of mass concentration.n.

• Asian Journal of Atmospheric Environment
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• v.6 no.3
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• pp.147-168
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• 2012

Among all hazardous air pollutants, polycyclic aromatic hydrocarbons (PAHs) are more significant owing to their carcinogenic, mutagenic and teratogenic properties. Many researchers worldwide have focused on determining the concentrations of PAHs in ambient air. However, the literature survey reveals that the seriousness of air pollution in Asia in terms of PAHs, compared to the rest of the world. Owing to the importance of PAHs in Asia, this paper reviews the concentrations of PAHs in Asia in recent years. For convenience, this paper describes the concentrations of PAHs in developed Asian countries reported during 2000-2011 as Part-I and in developing Asian countries as Part-II. The first section of this review provides a brief description of the properties, sources of PAHs and the health effects caused by their presence in the atmosphere. The ambient air PAH concentrations in both particle and vapor phases in developed Asian countries are then discussed. This study finds the ambient air concentrations of PAHs in developed Asian countries was higher than the Western countries but was lower than the developing Asian countries. The present review predicts the accurate toxicity due to the presence of PAHs in the atmosphere by calculating the Risk Weighted Concentration (RWC), regardless of the total amount of PAHs. The total data obtained during the literature survey is tabulated and presented as supplementary information to the readers.

• Journal of Environmental Health Sciences
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• v.33 no.5
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• pp.365-371
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• 2007

To evaluate the effect of air pollution on respiratory health in children, We conducted a longitudinal study in which children were asked to record their daily levels of Peak Expiratory Flow Rate(PEFR) using potable peak flow meter(mini-Wright) for 4 weeks. The relationship between daily PEFR and ambient air particle levels was analyzed using a mixed linear regression models including gender, age in year, weight, the presence of respiratory symptoms, and relative humidity as an extraneous variable. The daily mean concentrations of $PM_{10}$ and $PM_{2.5}$ over the study period were $64.9{\mu}g/m^3$ and $46.1{\mu}g/m^3$, respectively. The range of daily measured PEFR in this study was $182{\sim}481\;l/min$. Daily mean PEFR was regressed with the 24-hour average $PM_{10}(or\;PM_{2.5})$ levels, weather information such as air temperature and relative humidity, and individual characteristics including sex, weight, and respiratory symptoms. The analysis showed that the increase of air particle concentrations was negatively associated with the variability in PEFR. We estimated that the IQR increment of $PM_{10}$ or $PM_{2.5}$ were associated with 1.5 l/min (95% Confidence intervals -3.1, 0.1) and 0.8 l/min(95% CI -1.8, 0.1) decline in PEFR. Even though this study showed negative findings on the relationship between respiratory function and air particles, it was worth noting that the findings must be interpreted cautiously because exposure measurement based on monitoring of ambient air likely resulted in misclassification of true exposure levels and this was the first Korean study that $PM_{2.5}$ measurement was applied as an index of air quality.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.3
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• pp.353-360
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• 2006

This study identified a particle size distribution (PSD) of fine particulate matter and emission characteristics of V and Ni by the comparison between anthropogenic sources of oil combustion (industrial boiler, oil power plant, etc.) and lab-scale combustion using a drop-tube furnace. In oil combustion source, the mass fraction of fine particles (less than 2.5 micrometers in diameter) was higher than that of coarse particles (larger than 2.5 micrometers in diameter) in $PM_{10}$ (less than 10 micrometers in diameter) as like in lab-scale oil combustion. In addition to this, it was identified that ultra-fine particles (less than 0.1 micrometers in diameter) had a large distribution in fine particles. Toxic metals like V and Ni had large mass fractions in fine particles, and most of all was distributed in ultra-fine particles. Most of ultra-fine particles containing toxic metals have been emitted into ambient by combustion source because it is hard to control by the existing air pollution control device. Hence, we must be careful on these pollutants because it is obvious that these are associated with adverse health and environmental effect.

• Journal of Korean Society for Atmospheric Environment
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• v.7 no.3
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• pp.227-234
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• 1991

This study deals with concentration and light extinction of atmospheric aerosol in Seoul. From the measured aerosol size distribution for particle diameter ranging from 0.01 $\mum \sim 1.0 \mum$, extinction coefficient is calculated using the Mie theory. The results show that the diurnal variation of aerosol concentration, in general, reveals the lowest concentration in early morning and afternoon, while the highest at about 8 O'clock owing to the heavy traffic and accumulation of air pollution in the low atmosphere. However, aerosol concentration and extinction coefficient on April 7 give low values due to the advective wind. On the other hand, high aerosol concentration and extinction coefficenat are recorded on April 10 although solar radiation is weak. From the distribution of extinction coefficient we can find that aerosol particles of 0.1 $\mum \sim 1.0 \mum$ in diameter are highly effective on light extinction.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.209-210
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• 2003

최근 동북아시아지역의 급속한 산업발달과 더불어 많은 양의 오염물질을 대기로 배출하고 있다. 특히 중국의 급속한 산업화와 문화수준의 향상 등으로 인해 배출되는 막대한 양의 대기오염물질이 동북아시아지역에서 주기적으로 발생하는 황사와 함께 장거리 이동현상에 의해 우리나라 및 일본 등의 대기 에어로졸 질량 농도 및 화학적 조성에도 많은 변화를 가져올 정도로 직접적인 영향을 끼친다. 그 중에서도 입자 크기가 2.5~10$\mu\textrm{m}$사이에 있는 조대입자(coarse particle)의 광화학적 특성에 많은 변화를 야기시키는 것으로 알려져 있다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.193-194
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• 2003

최근 대기오염물질에 대한 관심 증가는 대표적인 2차 오염물질로 분류되는 오존에 대한 관심과 미세먼지에 대한 특히 많은 관심을 초래하고 있다. 특히 미세먼지 중 탄소성 물질(carbonaceous material)의 경우, 기존 연구를 결과를 통해 살펴보면 지역적인 차이는 있으나 PM$_{2.5}$ 총 농도의 약 10~70%, 26~60%, 20~80%의 분율을 나타내는 것으로 알려져 있다. 또한 탄소성 물질은 시정 장애 현상등과 관련하여 중요한 대상물질임으로 국내외적으로 많은 관심을 유발하고 있는 물질이다. 국내의 경우, 시정 장애 현상과 관련하여 한진석 등(1994)이 원소분석기(elemental analyzer, Perkin elmer model 240)를 이용하여 분석을 실시한 바 있으며. 시정거리 5 km 미만시 탄소의 시정 기여율이 35.5%를 보고한 바 있다. (중략)략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.391-392
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• 2003

한전 원자력 환경기술원에서는 중ㆍ저준위 방사성폐기물 유리화 기술의 상용화 가능성을 입증하기 위한 유리화 실증설비를 건설하여 시험 중에 있으며 이 유리화 기술은 유도 가열식 저온로(Cold Crucible Melter, CCM)에 폐기물을 투입하는 기술로서 폐기물의 부피 축소 효과와 더불어 최종 고화물로 생성되는 폐기물의 침출율이 매우 낮은 장점을 지닌다. 이와 같은 유리화 공정은 기존의 소각처리에서와 같이 폐기물의 열적 산화과정에 의해 유해오염가스와 입자성 물질이 발생된다. 따라서 이를 처리하기 위해배기체 처리공정(Off Gas Treatment System, OGTS)을 설치하여 환경 배출기준(SO$_2$300ppm, NO$_2$ 200ppm, CO 600ppm, HCI 50ppm, 분진 100mg/Nm$^3$ 등)을 만족하도록 하였고 특히 입자성 물질은 후단 OGTS나 배관내 침적으로 인한 방사성 오염을 막기 위해 CCM 후단에서 효율적으로 제거되어야만 한다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.195-196
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• 2003

대기에서 입경에 따른 먼지의 무게농도를 측정하는 방법은 cascade impactor와 MOUDI(Micro-Orifice Uniform Deposit Impactor) 등이 비교적 잘 정립되어 있는 반면, 입경에 따른 먼지 개수를 측정하는 방법에 대한 연구는 아직 미진한 상태이다(McMurry, 2000). 현재 시도되고 있는 먼지 입경별 개수 측정방법은 SMPS와 APS를 결합하여 직경 0.005~10 $\mu\textrm{m}$에 이르는 먼지의 입경에 따른 개수를 측정하는 방법이다. 그러나, 일반대기 조건에서 SMPS와 APS의 정확성이 문제시되는데, 특히0.5~10$\mu\textrm{m}$의 먼지를 대상으로 하는APS는 대기에서 포집 효율이 낮을 수 있으며 또한 저농도에 대한 정확성도 문제시될 수 있다(Shen et al, 2002; Kim et al., 2002) (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.327-328
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• 2003

경유자동차는 연료 특성상 매연을 포함한 입자상물질을 다량 배출하고 있으며, 이러한 디젤입자상물질은 인체에 유해한 발암성 및 돌연변이원성 물질들을 함유하고 있기 때문에 호흡 등을 통한 인체 유입시 건강에 매우 유해하다. 그러므로 디젤입자상물질을 저감시키기 위한 여러 가지 기술들 중 발생된 배출가스가 배기관을 통해 대기중으로 배출되기 전에 엔진 연소실과 배기관 사이에 후처리장치와 같은 기술들을 이용하여 이를 저감시키고 있다. 본 연구에서는 후처리장치들 중 세라믹필터에 백금과 같은 산화성이 우수한 촉매를 코팅하여 만든 촉매식 매연여과장치(DPF ; diesel particulate filter, SK제공)를 사용하였을 때 입자저감성능 및 입자크기별 분포특성을 살펴보고자 하였다. 이를 통해 도시대기오염 저감대책을 기초자료 및 환경학적, 보건학적 연구에 적극 활용하고자 한다. (중략)