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  • Detection of sub-5nm naturally charged carbonaceous materials from a sooting laminar premixed flame by a water condensation Particle Counter (WCPC) enhanced by a Di-Ethylene Glycol (DEG) saturator inlet
Title: Detection of sub-5nm naturally charged carbonaceous materials from a sooting laminar premixed flame by a water condensation Particle Counter (WCPC) enhanced by a Di-Ethylene Glycol (DEG) saturator inlet
Combustion is one of the major contributors to air pollution and Condensation Particle Counters (CPCs) provide effective monitoring of atmospheric aerosols since they can detect both charged and neutral materials in low number concentrations. The detection efficiency of any CPC for materials smaller than 5nm requires ad-hoc calibrations because it is affected by the analyte’s size, shape, charge state, composition, and wettability by the condensing fluid. This study characterizes a Water-based CPC (WCPC) prototype for the detection of the naturally charged carbonaceous products of an incipiently sooting laminar premixed flame. The WCPC can activate condensation growth and (50% efficient) detection of hydrophobic flame-formed carbonaceous materials naturally charged in positive and negative polarities with mobility diameters as small as 4.3nm and 4.8 nm, respectively. The addition of a simple Di-Ethylene Glycol (DEG) saturator inlet enhances the 50% detection cutoff to mobility diameters as small as 1.8 nm or 1.6nm for materials charged in positive or negative polarity, respectively. The coupling of the DEG saturator inlet to the WCPC creates a new DEG-WCPC instrument able to detect efficiently both hydrophobic and hydrophilic sub-5nm aerosols with a marginal increase in manufacturing cost (<10%), dimensions, and weight (<0.25 kg).  more » « less
Award ID(s):
2013382
PAR ID:
10553927
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Taylor and Francis
Date Published:
Journal Name:
Aerosol Science and Technology
Volume:
57
Issue:
11
ISSN:
0278-6826
Page Range / eLocation ID:
1069 to 1086
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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