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Article: Loss of P[M.sub.2.5] nitrate from filter samples in central California.(TECHNICAL PAPER)
- Article from:
- Journal of the Air & Waste Management Association
- Article date:
- August 1, 2005
- Author:
CopyrightCOPYRIGHT 2005 Air and Waste Management Association. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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ABSTRACT
Evaporative loss of particulate matter (with aerodynamic diameter
<10% during cold months to>80% during warm months. In agreement with theory, evaporative loss from quartz-fiber filters in nitric acid denuded samplers is controlled by the ambient nitric acid-to-particulate nitrate ratio, which is determined mainly by ambient temperature. Accurate estimation of nitrate volatilization requires a detailed thermodynamic model and comprehensive chemical measurements. For the 14-month average of P[M.sub.2.5] acquired on Teflon-membrane filters, measured P[M.sub.2.5] mass was 8-16% lower than actual P[M.sub.2.5] mass owing to nitrate volatilization. For 24-hr samples, measured ...