MOLECULAR BEAM SAMPLING OF UNSTABLE SPECIES FROM HIGH PRESSURE SYSTEMS.

Abstract

A technique has been developed for the mass spectrometric sampling of high temperature systems at atmospheric pressure and above. The gases to be sampled are expanded as a free jet, which is collimated into a molecular beam and introduced into the ion source of a mass spectrometer. Corrections must be made for two phenomena, mass separation and nucleation, which may accompany this sampling process. It has been possible to quantitatively sample stable products and free radicals from atmospheric and low pressure flames using a water-cooled probe. Condensible species have also been sampled using a probe in thermal equilibrium with the gas. It has not, however, been possible to sample with a cold probe species which form refractory condensed phases. These negative results with condensible species are attributed to interactions of the probe with the gas prior to the expansion. (Author)

Document Details

Document Type
Technical Report
Publication Date
Feb 01, 1967
Accession Number
AD0646935

Entities

People

  • Frank T. Greene
  • Thomas A. Milne

Tags

Communities of Interest

  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Barometric Pressure
  • Free Radicals
  • High Pressure
  • High Temperature
  • Ion Sources
  • Ions
  • Mass Spectrometers
  • Molecular Beams
  • Nucleation
  • Sampling
  • Spectrometers

Fields of Study

  • Chemistry

Readers

  • Aerosol Science/Aerosol Physics
  • Metallurgy
  • Quantum Chemistry