Accession Number:

AD0658667

Title:

AUTOMATIC COUNTING OF ATMOSPHERIC AEROSOLS COLLECTED WITH THE GOETZ ULTRACENTRIFUGE

Descriptive Note:

Technical rept.

Corporate Author:

ARMY ELECTRONICS COMMAND FORT MONMOUTHNJ

Personal Author(s):

Report Date:

1967-06-01

Pagination or Media Count:

40.0

Abstract:

An automatic counter was developed with which submicron aerosol data, collected with the Goetz Aerosol Spectrometer ultracentrifuge was rapidly and accurately evaluated. The data, consisting of 35mm microphotographs of large numbers of aerosols, were reduced by utilizing a unique track-scanning geometry in conjunction with a mechanical planar scanner. The photographic images of the aerosols and their locations on the data field were considered in detail, and appropriate corrections were derived to compensate for coincidence counting losses and the variable opacity of the images. Using the automatic counter, it was possible to count up to 500 aerosol images on a 2.0 sq cm area on each microphotograph. The counts were accomplished with a standard deviation of approximately 0.20 times the magnitude of the inherent statistical uncertainty of the data also, each microphotograph was automatically scanned and counted in 140 seconds.

Subject Categories:

  • Atmospheric Physics
  • Physical Chemistry
  • Air Pollution and Control

Distribution Statement:

APPROVED FOR PUBLIC RELEASE