Measurement of atmospheric peroxy radicals by chemical amplification
Presented herein is a new technique for the continuous measurement of peroxy and oxy radicals in air, based on the chain reaction in which these molecules participate to oxidize NO and CO to NO/sub 2/ and CO/sub 2/. Under typical instrument conditions, more than 1000 NO/sub 2/ molecules can be produced from each measurable radical entering the system. The NO/sub 2/ produced is measured by luminol chemiluminescence, based on the gas-surface reaction of NO/sub 2/ with a pH 12, 3 mM aqueous luminol solution. NO/sub 2/ produced from sources other than the chain reaction is measured by substitution of N/sub 2/ for CO half of the time. Therefore the radical signal is modulated with and determined by difference. The detection limit of radicals with this system is a strong function of the variability of ambient NO/sub 2/ and O/sub 3/, but usually less than 1 pptv (parts in 10/sup 12/ by volume) can be detected, with a precision of a few percent and an overall estimated accuracy of +/- 50%. Calibration procedures as well as results of some preliminary experiments using this method are presented. 26 references, 4 figures, 3 tables.
- Research Organization:
- Univ. of Michigan, Ann Arbor
- OSTI ID:
- 6030325
- Journal Information:
- Anal. Chem.; (United States), Vol. 56:8
- Country of Publication:
- United States
- Language:
- English
Similar Records
Chlorine atom-initiated low-temperature oxidation of prenol and isoprenol: The effect of C=C double bonds on the peroxy radical chemistry in alcohol oxidation
Application of natural radionuclides for determination of tropospheric ozone and aerosol transport.
Related Subjects
CARBON MONOXIDE
OXIDATION
NITRIC OXIDE
NITROGEN DIOXIDE
CHEMILUMINESCENCE
PEROXY RADICALS
AEROSOL MONITORING
ACCURACY
AIR
AIR POLLUTION
AQUEOUS SOLUTIONS
ATMOSPHERIC CHEMISTRY
BENCH-SCALE EXPERIMENTS
CALIBRATION
CHEMICAL REACTION YIELD
EXPERIMENTAL DATA
PH VALUE
PHOTOCHEMICAL REACTIONS
REACTION INTERMEDIATES
SENSITIVITY
TIME DEPENDENCE
AIR POLLUTION MONITORING
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
CHEMICAL REACTIONS
CHEMISTRY
DATA
DISPERSIONS
FLUIDS
GASES
INFORMATION
LUMINESCENCE
MIXTURES
MONITORING
NITROGEN COMPOUNDS
NITROGEN OXIDES
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
POLLUTION
RADICALS
SOLUTIONS
YIELDS
500200* - Environment
Atmospheric- Chemicals Monitoring & Transport- (-1989)