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511.
Source contributions to fine particulate matter in an urban atmosphere 总被引:10,自引:0,他引:10
This paper proposes a practical method for estimating source attribution by using a three-step methodology. The main objective of this study is to explore the use of the three-step methodology for quantifying the source impacts of 24-h PM2.5 particles at an urban site in Seoul, Korea. 12-h PM2.5 samples were collected and analyzed for their elemental composition by ICP-AES/ICP-MS/AAS to generate the source composition profiles. In order to assess the daily average PM2.5 source impacts, 24-h PM2.5 and polycyclic aromatic hydrocarbons (PAH) ambient samples were simultaneously collected at the same site. The PM2.5 particle samples were then analyzed for trace elements. Ionic and carbonaceous species concentrations were measured by ICP-AES/ICP-MS/AAS, IC, and a selective thermal MnO2 oxidation method. The 12-h PM2.5 chemical data was used to estimate possible source signatures using the principal component analysis (PCA) and the absolute principal component scores method followed by the multiple linear regression analysis. The 24-h PM2.5 source categories were extracted with a combination of PM2.5 and some PAH chemical data using the PCA, and their quantitative source contributions were estimated by chemical mass balance (CMB) receptor model using the estimated source profiles and those in the literature. The results of PM2.5 source apportionment using the 12-h derived source composition profiles show that the CMB performance indices; chi2, R2, and percent of mass accounted for are 2.3%, 0.97%, and 100.7%, which are within the target range specified. According to the average PM2.5 source contribution estimate results, motor vehicle exhaust was the major contributor at the sampling site, contributing 26% on average of measured PM2.5 mass (41.8 microg m-3), followed by secondary sulfate (23%) and nitrate (16%), refuse incineration (15%), soil dust (13%), field burning (4%), oil combustion (2.7%), and marine aerosol (1.3%). It can be concluded that quantitative source attribution to PM2.5 in an urban area where source profiles have not been developed can be estimated using the proposed three-step methodology approach. 相似文献
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513.
Wajih Ur Rehman Minhan Park Jihyo Chong Kwangyul Lee Jiho Jang 《Environmental Forensics》2020,21(1):48-58
AbstractTo determine the sources of particulate matter less than 2.5?μm (PM2.5 in different ambient atmospheres (urban, roadside, industrial, and rural sites), the chemical components of PM2.5 such as ions (Cl-, NO3-, SO42-, NH4+, Na+, K+, Ca2+, and Mg2+), carbonaceous species, and elements (Al, As, Ba, Cd, Cu, Fe, Mn, Ni, Pb, Se, V, and Zn) were measured. The average mass concentrations of PM2.5 at the urban, roadside, industrial, and rural sites were 31.5?±?14.8, 31.6?±?22.3, 31.4?±?16.0, and 25.8?±?12.4?μg/m3, respectively. Except for secondary ammonium sulfate and ammonium nitrate, the model results showed that the traffic source (i.e., the sum of gasoline and diesel vehicle sources) was the most dominant source of PM2.5 (17.1%) followed by biomass burning (13.8%) at the urban site. The major primary sources of PM2.5 were consistent with the site characteristics (diesel vehicle source at the roadside site, coal-fired plants at the industrial site, and biomass burning at the rural site). Seasonal data from the urban site suggested that ammonium sulfate and ammonium nitrate were the most dominant sources of PM2.5 during all seasons. Further, the contribution of road dust source to PM2.5 increased during spring and fall seasons. We conclude that the determination of the major PM2.5 sources is useful for establishing efficient control strategies for PM2.5 in different regions and seasons. 相似文献
514.
AlThuwaynee Omar F. Kim Sang-Wan Najemaden Mohamed A. Aydda Ali Balogun Abdul-Lateef Fayyadh Moatasem M. Park Hyuck-Jin 《Environmental science and pollution research international》2021,28(32):43544-43566
Environmental Science and Pollution Research - This study investigates uncertainty in machine learning that can occur when there is significant variance in the prediction importance level of the... 相似文献
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Kim Eunjung Gil Hyungbae Park Sangwon Park Jinwon 《Journal of Material Cycles and Waste Management》2017,19(1):423-431
Journal of Material Cycles and Waste Management - Slow pyrolysis is characterized by a low heating rate and high reaction time. The products are bio-char, bio-oil and bio-gas. In bio-oil, there are... 相似文献
518.
Ning Wang Jaeyoung Park Timothy G. Ellis 《Journal of Material Cycles and Waste Management》2014,16(3):475-481
The adsorption capacity of fine rubber particle media (FRPM) derived from discarded vehicle tires and the consumer wasted rubber sources was evaluated for hydrogen sulfide treatment. H2S breakthrough tests were performed at various zinc contents, temperatures, and packing quantities. High zinc concentrations increased the adsorption capacity of FRPM significantly. H2S removal by FRPM was optimized at a packing quantity of 75 % of the column volume, and the adsorption capacity increased with reactor temperature within the range of 20–85 °C. The regeneration of ZnCl2 solution was reliable for increasing regeneration capacity of the FRPM-adsorbed H2S. FRPM seems to be an attractive alternative of H2S adsorbents in terms of cost effectiveness compared to traditional materials. 相似文献
519.
C. R. Unelius K.-C. Park M. McNeill S. L. Wee B. Bohman D. M. Suckling 《Die Naturwissenschaften》2013,100(2):135-143
An investigation to identify a sex or aggregation pheromone of Sitona discoideus Gyllenhål (Coleoptera: Curculionidae) is presented. Antenna flicking and attraction behaviors evoked by conspecifics of both sexes were recorded in arena bioassays, where attraction of females to males was observed. Air entrainment of both males and females was conducted in separate chambers. Gas chromatographic–mass spectrometric analysis of headspace volatiles revealed that two male-specific compounds, 4-methyl-3,5-heptanedione (major) and (4S,5S)-5-hydroxy-4-methyl-3-heptanone (minor), were emitted during the autumnal post-aestivatory flight period. The stereoisomers of the minor component were separated by enantioselective gas chromatography and their absolute configurations assigned by NMR (diastereomers) and the known preference of enantioselective transesterification reactions catalyzed by Candida antarctica lipase B. Electroantennogram and single sensillum recording studies indicate that 4-methyl-3,5-heptanedione as well as all individual stereoisomers of 5-hydroxy-4-methyl-3-heptanone are detected by the antennae of male and female S. discoideus. Further, single sensillum recordings suggest that both sexes of S. discoideus have specialized olfactory receptor neurons (ORNs) for detecting 4-methyl-3,5-heptanedione and different populations of stereoselective ORNs for detecting the stereoisomers of 5-hydroxy-4-methyl-3-heptanone. Some of these stereoselective ORNs appear to be sex-specific in S. discoideus. 相似文献
520.
Structural Change of the Manufacturing Sector in Korea: Measurement of Real Energy Intensity and CO2 Emissions 总被引:1,自引:0,他引:1
Jung Tae Yong Park Tae Sik 《Mitigation and Adaptation Strategies for Global Change》2000,5(3):221-238
In terms of energy use, it is wellknown that energy intensity in the manufacturingsector is higher than any other sector. In Korea, theenergy intensity of the manufacturing sector hasdeteriorated since the late 1980s. This phenomenonis quite unique compared with the trend of energyintensity in other countries. In this study, weclosely examine the structural composition of Korea'smanufacturing sector from 1981 to 1996, its energyintensity, and its implications for carbon dioxide(CO2) emissions by introducing the measurement ofreal energy intensity.The conventional index of energy intensity is notappropriate for aggregate industries. Since theaggregation of industries in the manufacturing sectorincludes structural change, it would be better toseparate the effect of structural change. Hence, inthis study, we apply a decomposition methodology forenergy intensity based on the `Divisia Index'. Ateach industry level, energy intensity is a mixedmeasurement of pure energy efficiency improvement andfuel substitution. We also calculate real energyintensity at each industry level. Based on ouranalysis, we derive carbon dioxide (CO2) intensity and analyze the factors that affect CO2 emission in this sector.During 1988–1993, the energy intensity of themanufacturing sector in Korea deteriorated. Industrial structural change,the real energy intensity in this sector became evenworse during this period. The primary reason for thisphenomenon was that the share of energy intensiveindustries, such as steel, cement, and petro-chemicalindustries increased. Second, during the sameperiod, liquefied natural gas (LNG) rapidlypenetrated this sector, so that theCO2 intensity improved. We find thatharmonization of economic development strategies andenvironmental consideration is crucial for sustainabledevelopment. Based on our study, we derived somepolicy implications. Integration of industrialpolicies and energy efficiency improving programs isquite important, as well as the acceleration of fuelsubstitution to less carbon (C) intensive ones. Integration of local and global environmental policiesplays an important role for mitigatingCO2 emissions. 相似文献