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Concentrations of NH3 in (µg/m3) at different sites versus time in the period 4th April 2005 to 3rd April 2006. Measurements were done in 26 batches each of which lasted 14 days exposure interval. (filled diamonds) background area, (filled squares) industrial area, (filled triangles) traffic area, (ex marks) commercial area and (asterisks) residential area
