Photolysis system for fast-response NO2 measurements and method therefor
US6346419B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 26, 2000 |
| Grant date | Feb 12, 2002 |
| Priority date | — |
| Expiry date | Jun 26, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T436/178459
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An efficient, lightweight, and relatively inexpensive photolysis system based on a short-arc Hg arc lamp provides a simple and accurate method for measurement of ambient NO2. High time resolution is achieved by minimizing inlet and photolysis cell residence times and matching NO and NO2 sample paths, and data reduction is greatly simplified relative to conventional photolysis designs. The single-channel embodiment includes (a) a UV light source for emitting light capable of photolytically dissociating NO2 in the gas sample to NO; (b) a device for positioning the light source; (c) an ellipsoidal reflector for collecting and focusing the light from the light source; (d) an enclosure for enclosing the light source and the ellipsoidal reflector; (e) an optical filter assembly for receiving, filtering, and transmitting the focused light; (f) a shutter capable of blocking the transmission of the filtered light which is transmitted through the optical filter assembly; (g) a sample photolysis cell for containing a volume of the gas sample; (h) a device for controllably introducing the gas sample to the sample photolysis cell, and a device for controllably delivering the gas sample from the…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.