Trace water measurement
US4239967A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 13, 1979 |
| Grant date | Dec 16, 1980 |
| Priority date | — |
| Expiry date | Apr 13, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/623
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for measuring trace amounts of water in an atmosphere. A dry inert gas is used as the carrier gas and a dry gas comprising about 20 percent oxygen and about 80 percent inert gas is used as the reagent gas. The ionization source is operated at atmospheric pressure. A small electric field of about 200 volts per centimeter is applied across the ion drift chamber and it is biased to repel negative ions to a quadrupole mass filter. Measurements at an m/e value of 52 are integrated over a period of time. The results of the integration, when compared to a calibration chart, indicate the amount of water that had been present in the atmosphere being measured.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.