Method and apparatus for selectively extracting and compressing trace samples from a carrier to enhance detection
US6155097A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 29, 1998 |
| Grant date | Dec 5, 2000 |
| Priority date | — |
| Expiry date | May 29, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2030/623
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus is provided for increasing sensitivity for near-real-time detection of very low concentrations of diffusely distributed trace vapors in a carrier medium. Before admitting the trace vapor bearing carrier medium into a near-real-time GC/MS trace vapor detection system, the concentration of the trace vapor in the carrier medium, air in this instance, is increased by passing it through a membrane gas separator. The gas separator preferentially passes a portion of the trace vapor and rejects all but a very small portion of the carrier medium. The sample, highly concentrated in trace vapor with respect to the carrier medium after passing through the gas separator, is then compressed by a turbomolecular pump resulting in a substantial increase in density of the trace vapor at the exhaust port of the pump and a corresponding increase in detection sensitivity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.