Application of the Soft X-Ray TSI Advanced Aerosol Neutralizer to Aerosol Measurements Made by a Grimm SMPS

Alessia Nicosia, Franco Belosi, Brais Vazquez

Institute of Atmospheric Sciences and Climate (ISAC), Italian National Research Council, Bologna, Italy.

DOI: 10.4236/acs.2014.44056                

Abstract

Scanning Mobility Particle Sizer (SMPS) spectrometers are subject to several restrictions when a radioactive source is employed to bring the aerosol to a steady-state charge distribution. An alternative solution, commercially available, is represented by the soft X-ray neutralizer. The present study investigates the outcome of a combination of a Grimm SMPS, which employs a ²⁴¹Am radioactive source, with the soft X-ray advanced aerosol neutralizer (TSI model 3087). To date, the latter device has been interfaced only with TSI’s Electrostatic Classifiers. Particle size distribution of sodium chloride aerosol was measured with both neutralizers and it was found that the particle number concentration agreed to be within 9% for the 10 - 700 nm range. This difference mainly corresponds to the bias reported by TSI, when the X-ray device is mounted on a TSI spectrometer. It was concluded that the X-ray neutralizer could be usefully employed, as a standalone device, in combination with Grimm Electrostatic Classifiers.

Keywords

Aerosol Neutralizer, SMPS, Particle Size Distribution

Conflicts of Interest

The authors declare no conflicts of interest.

References

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