||Time-of-flight aerosol beam spectrometer for particle size measurements /
Dahneke, Barton Eugene.
||Rochester Univ., N.Y. Dept. of Radiation Biology and Biophysics.;Environmental Sciences Research Lab., Research Triangle Park, N.C.
|| U.S. Environmental Protection Agency, Office of Research and Development, Environmental Sciences Research Laboratory,
Time-of-flight mass spectrometry ;
Particle size determination ;
Particle size distribution ;
Aerodynamic characteristics ;
Stokes law(Fluid mechanics) ;
Rarified gas dynamics ;
Design criteria ;
Performance evaluation ;
Electronic equipment ;
Optical equipment ;
Vacuum apparatus ;
Air pollution ;
Time of flight aerosol beam spectrometers ;
Air pollution detection ;
||Research Triangle Park Library/RTP, NC
||Received from HQ
||Region 10 Library/Seattle,WA
||Some EPA libraries have a fiche copy filed under the call number shown.
||vii, 85 p. : ill. ; 28 cm.
A time-of-flight aerosol beam spectrometer (TOFABS) is described. The instrument has been designed and constructed to perform in situ real time measurements of the aerodynamic size of individual aerosol particles in the range 0.3 to 10 micrometers diameter. The measurement method consists of (1) allowing a sample aerosol to undergo expansion through a nozzle into a vacuum chamber, such that each particle acquires a terminal velocity depending on its aerodynamic size, then (2) measuring the terminal velocity by determining the time taken for each particle to traverse a laser beam of fixed width. An experimental calibration curve relating time-of-flight and aerodynamic size, based on the use of polystyrene latex spheres, is shown to be in good agreement with a theoretical calibration obtained from the gas-particle dynamics equations. A comprehensive discussion of the properties and uses of aerosol beams is included as an appendix.
"EPA-600/2-77-229." EPA grant no. R 803065 ; EPA project officer: Charles W. Lewis.