• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2003년도 International Symposium on Clean Environment
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• pp.79-84
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• 2003

The main objective of this study was to investigate the chemical characteristics of post-harvest biomass burning aerosols from field burning of barley straw in late spring and rice straw in late fall in rural area in Korea. 12-hr integrated intensive sampling of $PM_{10}$ and $PM_{2.5}$ biomass burning aerosols had been conducted continuously at Gwangju, Korea 4-15 June 2001 and 8 October-14 November 2002. The fine and coarse particles of biomass burning aerosols were collected for mass, ionic, elemental, and carbonaceous species analysis. Average fine and coarse mass concentrations of biomass burning aerosols were measured to be 129.6, 24.2 ${{\mu}gm}^{-3}$ in June 2001 and 47.1, 33.2 ${{\mu}gm}^{-3}$ in October to November 2002, respectively. Exceptionally high level of $PM_{2.5}$ concentration up to 157.8 ${{\mu}gm}^{-3}$ well above 24-hour standard was observed during the biomass burning event days under stagnant atmosphere condition. During biomass burning periods dominant ionic species were $Cl^{-}$, ${NO_3}^{-}$, ${SO_4}^{2-}$, and ${NH_4}^{+}$ in fine and coarse mode. In the fine mode $Cl^{-}$ and ${KCl}^{+}$ were unusually rich due to the high content of the semiarid vegetation. High OC values and OC/EC ratios were also measured during the biomass burning periods. Increased amount of fine aerosols with high enrichment, which were originated from biomass burning of post-harvest agricultural waste, resulted in extremely severe particulate air pollution and visibility degradation in the region. Particulate matters from open field burning of agricultural wastes cause great adverse impact on local air quality and regional climate.

• Asian Journal of Atmospheric Environment
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• 제5권2호
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• pp.79-85
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• 2011

The purpose of this study is to evaluate the strength of the near-UV wavelength of 380 nm relative to visible and near-IR bands, and to find the suitable wavelength for detecting aerosols by using the Global Imager (GLI) sensor aboard the Advanced Earth Observing Satellite-II (ADEOS-II). Sensitivity analysis is performed for the retrieval of biomass burning aerosols by employing the radiative transfer model Rstar5b. It is determined that background surface reflectance in the blue band is similar to that in the near-UV band, and that wavelengths in the blue bands are more sensitive to the Aerosol Optical Thickness (AOT) than wavelengths in the near-UV band. The Total Ozone Mapping Spectrometer (TOMS) Aerosol Index (AI) is used in the indirect method used for aerosol retrieval, and the wavelength pair 380 nm and 460 nm is determined to be the most sensitive to the AOT. The results of this study suggest that wavelengths in the blue bands are suitable for detecting biomass burning aerosols over the Korean peninsula.

• Asian Journal of Atmospheric Environment
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• 제7권2호
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• pp.95-104
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• 2013

The study of carbonaceous aerosols in the atmosphere is critical to understand the role of aerosols in human health and climate. Using standardized thermal optical transmittance methods, organic carbon (OC), elemental carbon (EC), and water soluble organic carbon (WSOC) were determined using a combustion sampling system for four types of agricultural crop residues (rice straw, red pepper stems, soybean stems, and green perilla stems) and eight types of forest trees (pine stems, pine needles, ginkgo stems, ginkgo leaves, maple stems, maple leaves, cherry stems, and cherry leaves). The aerosol particles between 0.056 and $5.6{\mu}m$ in size were analyzed using a Micro-Orifice Uniform Deposit Impactor (MOUDI). In the current study, the Carbonaceous Thermal Distribution (CTD) by carbon analyzer was discussed in order to understand the carbon fractions from the twelve types of biomass burning. Also, the concentration of OC, EC, WSOC, and water insoluble organic carbon (WIOC) detected in the emissions were described.

• Asian Journal of Atmospheric Environment
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• 제11권2호
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• pp.96-106
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• 2017

In this study, measurements of size-segregated particulate matter (PM) emitted from the combustion of rice straw, pine needles, and sesame stem were conducted in a laboratory chamber. The collected samples were used to analyze amounts of organic and elemental carbon (OC and EC), water-soluble organic carbon (WSOC), humic-like substances (HULIS), and ionic species. The light absorption properties of size-resolved water extracts were measured using ultraviolet-visible spectroscopy. A solid-phase extraction method was first used to separate the size-resolved HULIS fraction, which was then quantified by a total organic carbon analyzer. The results show that regardless of particle cut sizes, the contributions of size-resolved HULIS ($=1.94{\times}HULIS-C$) to PM size fractions ($PM_{0.32}$, $PM_{0.55}$, $PM_{1.0}$, and $PM_{1.8}$) were similar, accounting for 25.2-27.6, 15.2-22.4 and 28.2-28.7% for rice straw, pine needle, and sesame stem smoke samples, respectively. The $PM_{1.8}$ fraction revealed WSOC/OC and HULIS-C/WSOC ratios of 0.51 and 0.60, 0.44 and 0.40, and 0.50 and 0.60 for the rice straw, pine needle, and sesame stem burning emissions, respectively. Strong absorption with decreasing wavelength was found by the water extracts from size-resolved biomass burning aerosols. The absorption ${\AA}ngstr{\ddot{o}}m $ exponent values of the size-resolved water extracts fitted between 300 and 400 nm wavelengths for particle sizes of $0.32-1.0{\mu}m$ were 6.6-7.7 for the rice straw burning samples, and 7.5-8.0 for the sesame stem burning samples. The average mass absorption efficiencies of size-resolved WSOC and HULIS-C at 365 nm were 1.09 (range: 0.89-1.61) and 1.82 (range: 1.33-2.06) $m^2/g{\cdot}C$ for rice straw smoke aerosols, and 1.13 (range: 0.85-1.52) and 1.83 (range: 1.44-2.05) $m^2/g{\cdot}C$ for sesame stem smoke aerosols, respectively. The light absorption of size-resolved water extracts measured at 365 nm showed strong correlations with WSOC and HULIS-C concentrations ($R^2=0.89-0.93$), indicating significant contribution of HULIS component from biomass burning emissions to the light absorption of ambient aerosols.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2005년도 추계 학술발표회 발표논문집
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• pp.33-36
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• 2005

• 대한원격탐사학회지
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• 제21권4호
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• pp.273-285
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• 2005

본 연구에서는 GLI 센서의 자외선인 380nm, 가시광선 영 역의 400nm와 412nm, 가시광선의 푸른 파장영역인 460nm와 490nm, 근파장 적외선인 2100nm를 비교 분석하여 생체 소각 에어러솔 탐지에 효과적인 파장을 살펴보고자 하였다. 자외선 파장이 지표 반사도가 낮고 BRDF 효과도 작게 나타나므로 에어러솔 추정시 효과적이라고 알려져 있으나 412nm를 제외한 400nm, 460nm, 490nm에서 380nm와 비슷한 지표 반사도를 보였다. 지표 반사도 대비 방법을 2003년 5월에 적용해 에어러솔 반사도를 산출하였을때 460nm의 에어러솔 반사도가 380nm 보다 민감하게 나타났다. GLI의 두파장을 이용해 TOMS 에어러솔 지수를 산출하였을 때 생체 소각 에어러솔은 흡수성 에어러솔로 나타났으며 380nm와 460nm를 이용한 TOMS 에어러솔 지수가 AERONET의 에어러솔 광학 두께와 높은 상관관계를 보이며 에어러솔의 광학 두께에 민감하게 반응하고 있다. 그러므로 생체소각 에어러솔을 탐지할 때에는 가시광선의 푸른색 영역의 파장대가 효과적일 것으로 사료된다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.381-384
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• 2005

We have applied the TOMS aerosols retrieval algorithm to GLI measurements. TOMS has utilized the aerosol index, which is a measure of the change in spectral contrast due to the wavelength-dependent effects of aerosols. We have retrieved the GLI aerosol index, which is made by the pair of 380/400nm, 380/412nm, 380/460nm, and 412/460nm. We have found that the biomass burning aerosols represent the absorbing aerosols. In addition, the pair of 380/460nm has shown the best signal for detecting aerosols in Principal Component Analysis(PCA) and comparison of aerosol optical thickness from AERONET data. The theoretical aerosol index is also shown the best signal in the pair of 380/460nm.

• 한국지리정보학회지
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• 제15권1호
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• pp.184-196
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• 2012

바이오매스 연소 활동은 인위적 또는 자연적인 원인에 의하여 발생하며 연소과정에서 다량의 대기오염물질을 배출한다. 이 과정에서 발생한 온실가스와 대기 에어러솔은 대기환경 저해와 기후변화의 원인으로 알려져 있으나 바이오매스 연소 활동에 대한 감시와 대기환경에 미치는 영향을 파악하기가 쉽지 않다. 본 연구는 동북아 지역의 바이오매스 연소 활동의 현황과 대기환경에 미치는 영향을 평가하고자, 지구관측 위성인 Terra/MODIS 관측 자료를 이용하였다. 바이오매스 연소의 발생 원인은 매우 다양하지만, 주 연료가 공급되는 토지피복과 계절별 변화에 의존하므로, 본 연구에서는 지역별 토지피복과의 관련성과 시간에 따른 현황과 변화 패턴을 분석하였다. 그 결과, 가장 넓은 영역을 차지하고 있는 녹지대 또는 상록수림 지역에서의 발생수가 많았으며, 경작지에도 많은 발생횟수를 나타내었다. 그리고 대기 오염물질 중 하나인 대기 에어러솔의 상대적인 양을 나타내는 에어러솔 광학두께자료와 연소 자료와 비교결과는 두 산출물간 뚜렷한 연중 변화와 관련성이 있는 것으로 나타났다. 즉, 바이오매스 연소 활동이 지역 대기환경에 미치는 영향을 증명하였으며, 중국대륙에서 발생빈도가 증가하고 있어 지역 대기환경 및 기후변화에 영향을 줄 것으로 예상된다.

• Asian Journal of Atmospheric Environment
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• 제7권3호
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• pp.169-175
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• 2013

Measurement of the phosphorus concentration in aerosols in Beijing, which was a representative East Asian mega-city, was carried out. The optimum procedure for analyzing phosphorus in aerosols was found in this study. Recovery of phosphorus in environmental samples through the improved method was almost 100%. The concentration of phosphorus in TSP was $145{\pm}47\;ng/m^3$, with a seasonal variation showing high concentrations in winter and low concentrations in summer. The concentrations of phosphorus in $PM_{2.5}$ accounted for $35{\pm}6%$ of those in TSP, with no seasonal variations. The major source of phosphorus in aerosols in Beijing was soil dust, and additional sources of phosphorus in fine particles could be coal combustion and biomass burning.

• Journal of Korean Society for Atmospheric Environment
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• 제24권E1호
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• pp.32-43
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• 2008

Source samples were collected to construct source profiles for 9 different source types, including soil, road dust, gasoline/diesel-powered vehicles, a municipal incinerator, industrial sources, agricultural/biomass burning, marine aerosol, and a coal-fired power plant. Seasonal profiles for 'Chinese aerosol', aerosols derived from the urban area of China, were reconstructed from seasonal $PM_{2.5}$ compositions reported in Beijing, China. Ambient $PM_{2.5}$ at a receptor site was also measured during each of the four seasons, from April 2001 to February 2002, in Seoul. The Chemical Mass Balance receptor model was applied to quantify source contributions during the study period using the estimated source profiles. Consequently, motor vehicle exhaust (33.0%), in particular 23.9% for diesel-powered vehicles, was the largest contributor affecting the $PM_{2.5}$ levels in Seoul, followed by agricultural/biomass burning (21.5%) and 'Chinese aerosol' (13.1%), indicating contributions from long-range transport. The largest contributors by season were: for spring, 'Chinese aerosol' (31.7%); for summer, motor vehicle exhaust (66.9%); and for fall and winter, agricultural/biomass burning (31.1% and 40.1%, respectively). These results show different seasonal patterns and sources affecting the $PM_{2.5}$ level in Seoul, than those previously reported for other cities in the world.