Laboratory Studies of Tropospheric Ozone Formation: A Novel Technique for Probing Volatile Organic Hydrocarbon Oxidation

EPA Grant Number: U915563
Title: Laboratory Studies of Tropospheric Ozone Formation: A Novel Technique for Probing Volatile Organic Hydrocarbon Oxidation
Investigators: Garland, Eva R.
Institution: California Institute of Technology
EPA Project Officer: Lee, Sonja
Project Period: September 1, 1999 through September 1, 2002
Project Amount: $102,000
RFA: STAR Graduate Fellowships (1999) RFA Text |  Recipients Lists
Research Category: Academic Fellowships , Engineering and Environmental Chemistry , Fellowship - Chemistry and Materials Science

Objective:

The objective of this research project is to design and implement a novel method for directly probing the primary kinetics and reaction pathways of several alkoxy radicals.

Approach:

It will be possible to detect the primary reaction products of the alkoxy radical with a novel technique called cavity ringdown spectroscopy (CRDS). CRDS provides high sensitivity with a time scale of a few microseconds. Pulsed radiation is injected into a cavity containing the sample to be studied that is bordered by two highly reflective mirrors, and the transmitted radiation decays exponentially, with a lifetime determined by the mirror reflectivities and losses due to absorption over the effective path length. CRDS provides for greater sensitivity than traditional spectroscopic techniques.

Expected Results:

This highly sensitive spectroscopic technique should allow for unprecedented detection of primary reaction products, which will ultimately lead to a better understanding of tropospheric ozone formation. The reaction apparatus also can be modified to probe many other reactions that are important in the atmosphere.

Supplemental Keywords:

alkoxy, isomerization, ozone, troposphere, cavity ringdown spectroscopy, CRDS., RFA, Scientific Discipline, Air, Environmental Chemistry, tropospheric ozone, Atmospheric Sciences, Environmental Engineering, ambient ozone data, spectroscopic studies, volatile organic hydrocarbon oxidation, isomerization, alkoxy radicals

Progress and Final Reports:

  • 2000
  • 2001
  • Final