Related Experiment Video
Updated: Jul 9, 2026

08:59
Measuring Sub-23 Nanometer Real Driving Particle Number Emissions Using the Portable DownToTen Sampling System
Published on: May 22, 2020
Abstract:
Exhaust gases are electrically charged, usually positively but sometimes negatively. This charge does not depend on the electric potential of the vehicle. Whether the charge is positive or negative seems to depend on whether water droplets or carbon particles predominate in the exhaust.
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