Method of sensing acidic/acid-forming and oxidizable gases for use as a residual filter life indicator
US9310309B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 19, 2013 |
| Grant date | Apr 12, 2016 |
| Priority date | — |
| Expiry date | Dec 19, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/645
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Processes of detecting the presence of an environmental challenge such as contact with an acidic/acid-forming and/or oxidizable gas are provided whereby a metal oxyhydroxide is used as a detection agent. The metal oxyhydroxide will irreversibly interact with an acidic/acid-forming and/or oxidizable gas causing a red-stretch of the emission spectra. This red-stretch alters the ratio of emission intensities at higher wavelengths relative to lower wavelengths. A reduced post-exposure photoluminescence ratio is, therefore, used to detect exposure to such a gas or environmental challenge. The materials and processes may be used as a residual life indicator for filtration systems or for the detection of environmental challenges.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.