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Changes in the total particle number 1-hour concentrations (a) and particle number of the 13 PM fractions; (b) 1-hour concentrations in winter (January 1, 2010–March 31, 2010, and October 1, 2010–October 7, 2010); (c) 1-hour concentrations in summer (April 1, 2010–September 30, 2010); (d) 1-hour concentrations entire measurement period (January 1, 2010–October 7, 2010), within 24-hour period.
