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A directional passive air sampler for monitoring polycyclic aromatic hydrocarbons (PAHs) in air mass
2008
Tao, S. | Liu, Y.N. | Lang, C. | Wang, W.T. | Yuan, H.S. | Zhang, D.Y. | Qiu, W.X. | Liu, J.M. | Liu, Z.G. | Liu, S.Z. | Yi, R. | Ji, M. | Liu, X.X.
A passive air sampler was developed for collecting polycyclic aromatic hydrocarbons (PAHs) in air mass from various directions. The airflow velocity within the sampler was assessed for its responses to ambient wind speed and direction. The sampler was examined for trapped particles, evaluated quantitatively for influence of airflow velocity and temperature on PAH uptake, examined for PAH uptake kinetics, calibrated against active sampling, and finally tested in the field. The airflow volume passing the sampler was linearly proportional to ambient wind speed and sensitive to wind direction. The uptake rate for an individual PAH was a function of airflow velocity, temperature and the octanol–air partitioning coefficient of the PAH. For all PAHs with more than two rings, the passive sampler operated in a linear uptake phase for three weeks. Different PAH concentrations were obtained in air masses from different directions in the field test. A novel directional passive air sampler was developed and tested for monitoring PAHs in air masses from different directions.
Show more [+] Less [-]Wet Deposition of Nitrogenous Pollutants and the Effect of Storm Duration and Wind Direction: A Case Study from Inland Southern California
2008
Padgett, Pamela E. | Minnich, Richard A.
Meteorological factors affecting concentration of dissolved inorganic nitrogen in rain were examined. Rain samples were collected on an event basis from a location 100 km east of the Los Angeles Basin. Analysis of the data demonstrated a double decay function where small increases in rain volume resulted in large decreases in nitrogen concentration. In separate time series collections of individual storms, storm wind direction also influenced nitrogen concentrations
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