skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Ion generation and CPC detection efficiency studies in sub 3-nm size range

Journal Article · · AIP Conference Proceedings
DOI:https://doi.org/10.1063/1.4803236· OSTI ID:22116033
; ; ; ;  [1];  [1]; ;  [2];  [3];  [4]
  1. Department of Physics, P.O. Box 64, 00014, University of Helsinki, Helsinki (Finland)
  2. Airmodus Ltd., Finland, Gustaf Haellstroemin katu 2 A, 00560 Helsinki (Finland)
  3. University Paris Est Creteil, University Paris-Diderot, LISA, UMR CNRS 7583 (France)
  4. Department of Physics, P.O. Box 64, 00014, University of Helsinki, Helsinki (Finland) and Aerodyne Research Inc., Billerica, MA (United States)

We studied the chemical composition of commonly used condensation particle counter calibration ions with a mass spectrometer and found that in our calibration setup the negatively charged ammonium sulphate, sodium chloride and tungsten oxide are the least contaminated whereas silver on both positive and negative and the three mentioned earlier in positive mode are contaminated with organics. We report cut-off diameters for Airmodus Particle Size Magnifier (PSM) 1.1, 1.3, 1.4, 1.6 and 1.6-1.8 nm for negative sodium chloride, ammonium sulphate, tungsten oxide, silver and positive organics, respectively. To study the effect of sample relative humidity on detection efficiency of the PSM we used different humidities in the differential mobility analyzer sheath flow and found that with increasing relative humidity also the detection efficiency of the PSM increases.

OSTI ID:
22116033
Journal Information:
AIP Conference Proceedings, Vol. 1527, Issue 1; Conference: 19. international conference on nucleation and atmospheric aerosols, Fort Collins, CO (United States), 23-28 Jun 2013; Other Information: (c) 2013 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
Country of Publication:
United States
Language:
English