Detection system for a gas chromatograph
Abstract
A method and apparatus are described for the quantitative analysis of vaporizable compounds, and in particular of polycyclic aromatic hydrocarbons which may be induced to fluoresce. The sample to be analyzed is injected into a gas chromatography column and is eluted through a narrow orifice into a vacuum chamber. The free expansion of the eluted sample into the vacuum chamber creates a supersonic molecular beam in which the sample molecules are cooled to the extent that the excited vibrational and rotational levels are substantially depopulated. The cooled molecules, when induced to fluoresce by laser excitation, give greatly simplified spectra suitable for analytical purposes. The laser induced fluorimetry provides great selectivity, and the gas chromatograph provides quantitative transfer of the sample to the molecular beam.
- Inventors:
-
- Ames, IA
- Issue Date:
- Research Org.:
- Ames Laboratory (AMES), Ames, IA; Iowa State Univ., Ames, IA (United States)
- OSTI Identifier:
- 864888
- Patent Number(s):
- 4432225
- Assignee:
- United States of America as represented by United States (Washington, DC)
- Patent Classifications (CPCs):
-
G - PHYSICS G01 - MEASURING G01N - INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- DOE Contract Number:
- W-7405-ENG-82
- Resource Type:
- Patent
- Country of Publication:
- United States
- Language:
- English
- Subject:
- detection; gas; chromatograph; method; apparatus; described; quantitative; analysis; vaporizable; compounds; particular; polycyclic; aromatic; hydrocarbons; induced; fluoresce; sample; analyzed; injected; chromatography; column; eluted; narrow; orifice; vacuum; chamber; free; expansion; creates; supersonic; molecular; beam; molecules; cooled; extent; excited; vibrational; rotational; levels; substantially; depopulated; laser; excitation; greatly; simplified; spectra; suitable; analytical; purposes; fluorimetry; provides; selectivity; transfer; aromatic hydrocarbons; quantitative analysis; gas chromatography; vacuum chamber; molecular beam; gas chromatograph; aromatic hydrocarbon; laser induced; chromatography column; laser excitation; polycyclic aromatic; chamber creates; free expansion; /73/250/
Citation Formats
Hayes, John M, and Small, Gerald J. Detection system for a gas chromatograph. United States: N. p., 1984.
Web.
Hayes, John M, & Small, Gerald J. Detection system for a gas chromatograph. United States.
Hayes, John M, and Small, Gerald J. Sun .
"Detection system for a gas chromatograph". United States. https://www.osti.gov/servlets/purl/864888.
@article{osti_864888,
title = {Detection system for a gas chromatograph},
author = {Hayes, John M and Small, Gerald J},
abstractNote = {A method and apparatus are described for the quantitative analysis of vaporizable compounds, and in particular of polycyclic aromatic hydrocarbons which may be induced to fluoresce. The sample to be analyzed is injected into a gas chromatography column and is eluted through a narrow orifice into a vacuum chamber. The free expansion of the eluted sample into the vacuum chamber creates a supersonic molecular beam in which the sample molecules are cooled to the extent that the excited vibrational and rotational levels are substantially depopulated. The cooled molecules, when induced to fluoresce by laser excitation, give greatly simplified spectra suitable for analytical purposes. The laser induced fluorimetry provides great selectivity, and the gas chromatograph provides quantitative transfer of the sample to the molecular beam.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 1984},
month = {Sun Jan 01 00:00:00 EST 1984}
}