title: Chemical and physical properties of ultrafine diesel exhaust particles sampled downstream of a catalytic trap.
abstract: The chemical and physical properties of exhaust particles produced by a Caterpillar 3176 C-12 heavy duty diesel engine equipped with a catalytic trap (CRT) are reported. The engine was operated at 600 Nm and 1500 rpm, using fuels containing 15 and 49 ppm sulfur. A two-stage dilution tunnel designed to simulate the reactions that occur when hot combustion products mix with cooler atmospheric air was used. Particle size distributions were measured using a scanning mobility particle sizer (SMPS) and nano-scanning mobility particle sizer (nano SMPS); a nanomicro-orifice uniform deposit impactor (nano MOUDI) collected size-resolved samples for gravimetric and chemical analysis. A nanometer tandem differential mobility analyzer (nano TDMA) was used to measure the volatility and hygroscopicity of 4-15 nm particles. These measurements confirm that the particles consisted primarily of sulfates.
authors.affiliation: Department of Mechanical Engineering, University of Minnesota, 111 Church Street SE, Minneapolis, Minnesota 55455, USA.
authors.forename: Melissa
authors.initials: M
authors.lastname: Grose
authors.forename: Hiromu
authors.initials: H
authors.lastname: Sakurai
authors.forename: Jake
authors.initials: J
authors.lastname: Savstrom
authors.forename: Mark R
authors.initials: MR
authors.lastname: Stolzenburg
authors.forename: Winthrop F
authors.initials: WF
authors.lastname: Watts
authors.forename: Christopher G
authors.initials: CG
authors.lastname: Morgan
authors.forename: Ian P
authors.initials: IP
authors.lastname: Murray
authors.forename: Martyn V
authors.initials: MV
authors.lastname: Twigg
authors.forename: David B
authors.initials: DB
authors.lastname: Kittelson
authors.forename: Peter H
authors.initials: PH
authors.lastname: McMurry
mesh_terms: D000393:Air Pollutants; D002384:Catalysis; D010316:Particle Size; D001335:Vehicle Emissions
chemical_list: D000393:Air Pollutants; D001335:Vehicle Emissions