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Peroxy radical detection by chemical amplification (perca)
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Stedman, D. H. |
| Copyright Year | 1986 |
| Description | Important reactions of atmospheric free radicals are the chain oxidation of NO and CO. Thus: H2O + NO yields OH + NO2; OH + CO yields H + CO2; H + O2 + M yields HO2 + M. In most models, the need to know the free radical concentration could also be described as the need to know the rate of the above oxidation chain in the atmosphere. It is the total rate of this chain (also carried by RO2 and RO) which was measured using the PERCA. The PERCA is thus essentially a RO sub X meter. The PERCA works by adding excess CO (10%) and NO (5ppm) to a stream of air and measuring the NO2 produced after 3s of reaction time. Since other processes produce NO2, the chain reaction is modulated by switching the CO for N2. The chain length is limited by the reaction OH + NO yields HONO and is modeled to be somewhat over 1000. Measured chain lengths agree with the modeled numbers. |
| File Size | 88776 |
| Page Count | 2 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19870006107 |
| Archival Resource Key | ark:/13960/t6353j51k |
| Language | English |
| Publisher Date | 1986-12-01 |
| Access Restriction | Open |
| Subject Keyword | Geophysics Hydrogen Peroxide Free Radicals Atmospheric Composition Nitrous Oxides Reaction Kinetics Hydroxyl Radicals Oxidation Carbon Monoxide Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
