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원주시 숯가마 및 산업단지 인근에서 측정한 PM2.5 이온 및 탄소 성분 특성
홍세인,이승묵,한영지 한국대기환경학회 2023 한국대기환경학회지 Vol.39 No.2
In this study, PM2.5 samples were collected at two sampling sites near the Munmak industrial complex and a charcoal kiln, and their ionic and carbonaceous constituents were measured. Average PM2.5 concentrations were 21.8±13.1 μg/m3 and 39.7±24.0 μg/m3 at the sites near the industrial complex and the charcoal klin, respectively. At the charcoal kiln site, organic carbon (OC) contributed 50.6% to PM2.5 mass and there was a significant correlation between PM2.5 and OC, indicating that PM2.5 concentration was greatly influenced by OC. The influence of charchol kiln on EC was much lower than on OC; therefore, a very high OC/EC ratio was observed. On the other hand, the contribution of ionic constituents (including NO3 -, SO4 2-, and NH4 +) for PM2.5 was much higher at the sampling site near the industrial complex than at the charcol kiln site. With the southwesterly winds blown from the industrial complex, the concentrations of PM2.5 and ionic components significantly increased. Correlation of OC concentrations between two sampling sites was not significant, but the correlation coefficients of ionic components between two sampling sites were very high. These results suggest that OC was influenced by local sources (charcoal kiln or industrial complex) but the ionic components were considered to be more influenced by medium- or long range transport than by local emission source.
Shuai Ji,Yujie Wang,Shikai Gao,Xian Shao,Wei Cui,Yan Du,Mengzhe Guo,Daoquan Tang 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.80 No.-
Lots of minor constituents in herbal medicines have shown great potential to devolve into leadcompounds, and their extraction is attracting more and more attention in pharmaceutical industry. Thisstudy provided an example that showed efficient and selective extraction of minor bioactive naturalproducts (prenylatedflavonoids with anti-cancer activities) from an herbal medicine (licorice) using pureionic liquids as green solvents. After investigation of a variety of hydrophobic ionic liquids withultrasonic-assisted extraction, we found that [C8MIM]BF4 (1-octyl-3-methylimidazolium tetrafluor-oborate) was the most effective one for extraction offive representative compounds (isoangustone A,glycycoumarin, licoisoflavanone, licoricidin and glabridin), and solvent to solid ratio, extraction time,extraction temperature and soaking time were then optimized through single-factor experiments andresponse surface methodology. As a result, the established method had significantly higher extractionselectivity than conventional organic solvents, which could be attributed to significant physical change oflicorice microstructures after extraction, as well as strong interactions (especially hydrogen bondinteractions) between [C8MIM]BF4 and prenylatedflavonoids by mechanism study. In addition, 78.92% ofthe extracted prenylatedflavonoids could be readily recovered from [C8MIM]BF4 by using reversed-phasesolid phase extraction, and the recyclability of [C8MIM]BF4 was also confirmed.