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Zheng J.,South China University of Technology | Zheng J.,Pearl River Delta Atmospheric Environment Research Joint Laboratory | He M.,South China University of Technology | He M.,Pearl River Delta Atmospheric Environment Research Joint Laboratory | And 6 more authors.
Science of the Total Environment | Year: 2012

A high-resolution regional black carbon (BC) and organic carbon (OC) emission inventory for the year 2009 was developed for the Pearl River Delta (PRD) region, China, based on the collected activity data and the latest emission factors. PM2.5, BC and OC emissions were estimated to be 303kt, 39kt and 31kt, respectively. Industrial processes were major contributing sources to PM2.5 emissions. BC emissions were mainly from mobile sources, accounting for 65.0%, while 34.1% of OC emissions were from residential combustion. The primary OC/BC ratios for individual cities in the PRD region were dependent on the levels of economic development due to differences in source characteristics, with high ratios in the less developed cities and low ratios in the central and southern developed areas. The preliminary temporal profiles were established, showing the highest OC emissions in winter and relatively constant BC emissions throughout the year. The emissions were spatially allocated into grid cells with a resolution of 3km×3km. Large amounts of BC emissions were distributed over the central-southern PRD city clusters, while OC emissions exhibited a relatively even spatial distribution due to the significant biomass burning emissions from the outlying area of the PRD region. Uncertainties in carbonaceous aerosol emissions were usually higher than in other primary pollutants like SO2, NOx, and PM10. One of the key uncertainty sources was the emission factor, due to the absence of direct measurements of BC and OC emission rates. © 2012 Elsevier B.V. Source

Zheng J.Y.,South China University of Technology | Zheng J.Y.,Pearl River Delta Atmospheric Environment Research Joint Laboratory | Yin S.S.,South China University of Technology | Yin S.S.,Pearl River Delta Atmospheric Environment Research Joint Laboratory | And 4 more authors.
Atmospheric Chemistry and Physics | Year: 2012

Detailed NH3 emission inventories are important to understand various atmospheric processes, air quality modeling studies, air pollution management, and related environmental and ecological issues. A high-resolution NH3 emission inventory was developed based on state-of-the-science techniques, up-to-date information, and advanced expert knowledge for the Pearl River Delta region, China. To provide model-ready emissions input, this NH 3 emissions inventory was spatially allocated to 3 km × 3 km grid cells using source-based spatial surrogates with geographical information system (GIS) technology. For NH3 emissions, 9 source categories and 45 subcategories were identified in this region, and detailed spatial and temporal characteristics were investigated. Results show that livestock is by far the most important NH3 emission source by contributing about 61.7% of the total NH3 emissions in this region, followed by nitrogen fertilizer applications (∼23.7%) and non-agricultural sources (∼14.6%). Uncertainty analysis reveals that the uncertainties associated with different sources vary from source to source and the magnitude of the uncertainty associated with a specific source mainly depends on the degree of accuracy of the emission factors and activity data as well as the technique used to perform the estimate. Further studies should give priority to the hog, broiler, goose subsectors of the livestock source and N fertilizer application source in order to reduce uncertainties of ammonia emission estimates in this region. The validity of the NH3 emissions inventory is justified by the trend analysis of local precipitation compositions, such as pH values, the Ca 2++NH4+/SO4 -2+ NO- 3 ratios, and NH4 + concentrations which are directly or indirectly related to NH3 emissions. © 2012 Author(s). Source

Zheng J.,South China University of Technology | Zheng J.,Pearl River Delta Atmospheric Environment Research Joint Laboratory | Yu Y.,South China University of Technology | Mo Z.,South China University of Technology | And 10 more authors.
Science of the Total Environment | Year: 2013

Industrial sector-based VOC source profiles are reported for the Pearl River Delta (PRD) region, China, based source samples (stack emissions and fugitive emissions) analyzed from sources operating under normal conditions. The industrial sectors considered are printing (letterpress, offset and gravure printing processes), wood furniture coating, shoemaking, paint manufacturing and metal surface coating. More than 250 VOC species were detected following US EPA methods TO-14 and TO-15. The results indicated that benzene and toluene were the major species associated with letterpress printing, while ethyl acetate and isopropyl alcohol were the most abundant compounds of other two printing processes. Acetone and 2-butanone were the major species observed in the shoemaking sector. The source profile patterns were found to be similar for the paint manufacturing, wood furniture coating, and metal surface coating sectors, with aromatics being the most abundant group and oxygenated VOCs (OVOCs) as the second largest contributor in the profiles. While OVOCs were one of the most significant VOC groups detected in these five industrial sectors in the PRD region, they have not been reported in most other source profile studies. Such comparisons with other studies show that there are differences in source profiles for different regions or countries, indicating the importance of developing local source profiles. © 2013. Source

Wang J.,South China University of Technology | Wang J.,Pearl River Delta Atmospheric Environment Research Joint Laboratory | Lai S.,South China University of Technology | Lai S.,Pearl River Delta Atmospheric Environment Research Joint Laboratory | And 8 more authors.
Environmental Geochemistry and Health | Year: 2014

To assess the exposure doses of PM2.5 and to investigate its chemical components for the subpopulation (i.e., school children and industrial downwind residents), simultaneous sampling of indoor and outdoor PM2.5 was conducted at an elementary school close to traffic arteries and a residence located in the downwind area of a steel plant in metropolitan Guangzhou in 2010. Chemical components, i.e., organic carbon, elemental carbon and 6 water soluble ions were analyzed in PM2.5. A survey was also conducted to investigate the time-activity patterns of the school children and the industrial downwind residents. Indoor and outdoor PM2.5 were 63.2 ± 20.1 and (76.7 ± 35.8) μg/m3 at the school, and 118.8 ± 44.7 and 125.7 ± 57.1 μg/m3 in the community, respectively. Indoor PM2.5 was found to be highly related to outdoor sources, and stationary sources were the significant contributors to PM2.5 at both sites. The daily average doses of PM2.5 for the school children at the school (D children) and the industrial downwind residents in the community (D residents) were (7.6 ± 1.9) and (36.1 ± 36.8) μg/kg-day, respectively. The daily average doses of particulate organic mass and SO4 2- were the two most abundant chemical components in PM2.5. PM2.5 exposure for the school children was contributed by indoor and outdoor environments by 48.8 and 51.2 %, respectively; for the industrial downwind residents, the contributions were 66.0 and 34.0 %, respectively. Age and body weight were significantly and negatively correlated with D children, while age, body weight and education level were significantly and negatively correlated with D residents; gender was not a significant factor at both cases. © 2013 Springer Science+Business Media Dordrecht. Source

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