@article{kang_aneja_das_seila_2004, title={Measurements of air-surface exchange rates of volatile organic compounds}, volume={22}, ISSN={["0957-4352"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-11244260492&partnerID=MN8TOARS}, DOI={10.1504/IJEP.2004.005909}, abstractNote={Vertical gradients of volatile organic compounds (VOCs) were measured over a maize field and a soybean field in 1995 and 1996, respectively, in the Lower Coastal Plains of North Carolina. The measurements over the maize field were conducted in its early growth period, during May 1995, and the measurements over the soybean field were conducted in its middle and later growth periods during July through August 1996 at the same location. These measurements were combined with micrometeorological flux measurements to determine emission flux measurements for various VOCs. This measurement programme was part of project NOVA (Natural emissions of Oxidant precursors: Validation of techniques and Assessment) to estimate the flux of VOCs. Methanol was identified as the major biogenic compound for both years with the average flux of 3450 ± 1456 µg/m²/hr over maize and 3079 ± 2766 µg/m²/hr over soybean. Acetone is another compound that was identified as a biogenic compound for both years with the average flux of 425 ± 223 µg/m²/hr over maize and 2701 ± 1710 µg/m²/hr over soybean. In addition to biogenic compounds, a large number of aromatic compounds, including styrene and 1,2,4-trimethylbenzene, were also identified as emissions from the ground over the soybean field.}, number={5}, journal={INTERNATIONAL JOURNAL OF ENVIRONMENT AND POLLUTION}, author={Kang, D and Aneja, VP and Das, M and Seila, R}, year={2004}, pages={547–562} }
 @article{das_aneja_2003, title={Regional analysis of nonmethane volatile organic compounds in the Lower Troposphere of the Southeast United States}, volume={129}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-0346749358&partnerID=MN8TOARS}, DOI={10.1061/(asce)0733-9372(2003)129:12(1085)}, abstractNote={Nonmethane organic compounds (NMOCs) along with ozone as well as other trace gas and meteorological parameters were measured at eight rural sites located in the Southeast United States, as part of the Southern Oxidants Study. Fifty-four C2C10 NMOCs were collected from 1,2001,300 local time, once every six days from September 1992 through October 1993 and intermittently during 1994. This study was undertaken to characterize the nonmethane hydrocarbons in the rural areas of Southeast United States with respect to their concentrations, reactivities, and relative importance of natural and anthropogenic abundances of NMOCs. Though the sites are well removed from large urban source regions, the observations show a clear anthropogenic influence on the hydrocarbon levels at these rural sites. The data for the sites show similar seasonal patterns for total NMOC with summer maxima (average concentrations of 198 ppbC at the Long Creek, South Carolina, site to 47 ppbC at the Candor, North Carolina site) and fall minima (average concentrations of 73 ppbC at the Long Creek site to 31 ppbC at the Centreville, Alabama site). A secondary maximum is observed during the winter. A seasonal trend was observed in the concentrations of light molecular weight C\d2–C\d4 NMOCs (ethane, ethene, acetylene, propane, \ii-butane, and \in-butane) with a winter maximum and a summer minimum. An analysis of changes in C\d2–C\d4 hydrocarbon ratios over a period of one year indicates that the variation is most likely due to seasonal changes in OH concentrations. A seasonal trend was also observed for the biogenically emitted NMOC, isoprene, with summer maxima (average concentrations of 37 ppbC at the Long Creek, South Carolina, site to 8.6 ppbC at the Giles County, Tennessee and Metter, Georgia, sites) and winter minima with winter seasonal values below the level of detection. Isoprene was observed to be the most dominant NMOC at most sites during the summer. The ambient concentrations of isoprene measured during the summer were found to be dependent on the ambient temperature. The monoterpenes \ia-pinene, \ib-pinene, and \id-limonene also peaked during the summer with averages ranging between 3.19 ppbC (Centreville, Alabama) and 6.38 ppbC (Oak Grove, Missouri), and a background concentration of 1.25 to 1.9 ppbC for all the sites during the winter.}, number={12}, journal={Journal of Environmental Engineering}, author={Das, M. and Aneja, Viney}, year={2003}, pages={1085–1103} }