Water vapor addition for gas chromatography, and gas chromatographs
US4806315A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 2, 1987 |
| Grant date | Feb 21, 1989 |
| Priority date | — |
| Expiry date | Jul 2, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N30/34
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The disclosure relates to improvements in the art of gas chromatography, and gas chromatographs containing a detector operated on the thermal conductivity principle. In the conventional gas chromatograph, a pair of resistance filaments constitutes an opposite arm of a Wheatstone bridge, and each of two pairs of filaments provides a reference side and a measuring side, respectively, across which a carrier gas can be flowed and the bridge balanced. A moisture-containing sample can be input and transported via carrier gas through a circuit to a substrate filled column and the moisture and other components of the sample separated according to their different affinities for the column substrate. The sample constituents elute from the column in characteristic sequence as elution bands diluted with carrier gas. The column effluent, in such system, can be flowed across the pair of resistance filaments constituting the measuring side of the bridge and the bridge unbalanced to create a bridge-inbalance signal which can be processed as output data indicative of the moisture contained in the sample. The present invention is based on the discovery that a constant and continuous amount of water …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.