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21 PSI Villigen Switzerland Comparing SMPS Particle Size Distributions with DC , PAS and CPC Data
| Content Provider | Semantic Scholar |
|---|---|
| Author | Bukowiecki, Nicolas Kittelson, David B. Watts, Winthrop F. Baltensperger, Urs Weingartner, Ernest |
| Copyright Year | 2001 |
| Abstract | Diesel particle number size distributions show typical key parameters, both for ambient diesel exhaust measurements and for laboratory dynamometer experiments. Two modes dominate the size distributions in the range 5– 300 nm, a soot mode at 60 – 120 nm and an ultrafine nucleation mode at 5 – 40 nm. The concentration of the soot mode is usually directly connected to the amount of particles emitted by the source, while the presence of the nucleation mode has been shown to strongly depend on the dilution conditions of the raw exhaust prior to the particle measurement. SMPS (Scanning Mobility Particle Sizer) size number distributions have good particle size resolution, but relatively poor time resolution, with scan times of 1 minute or more. DC, PAS and CPC are real-time instruments for particle measurement with a time resolution of 10 seconds or less. The combination DC, PAS and CPC has been shown to deliver realtime key information on diesel exhaust size distributions. First, diesel exhaust plumes which contain a highly concentrated ultrafine nucleation mode can be clearly identified using the ratio of DC vs. PAS signals, in the sense of a yes/no answer. Furthermore, the diameter of average surface of the sampled diesel aerosol can be determined using DC and CPC data. This allows qualitative statements on the dynamic behavior of the nucleation mode during an experiment, since the diameter of average surface will shift as the concentration of the nucleation mode changes. Using these findings, real-time monitoring of general traffic exhaust in test bench as well as field studies is possible with the use of these three instruments. |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | http://nanoparticles.ch/archive/2000_Bukowiecki_PR.pdf |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
