Showing papers by "A. R. Ravishankara published in 2002"
TL;DR: In this article, cavity ring-down spectroscopy (CaRDS) was applied to simultaneous measurement of nitrate radical, NO3, and dinitrogen pentoxide, N2O5, in the ambient atmosphere.
Abstract: This article describes the application of cavity ring-down spectroscopy (CaRDS) to the simultaneous concentration measurement of nitrate radical, NO3, and dinitrogen pentoxide, N2O5, in the ambient atmosphere. The sensitivity for detection of both NO3 and N2O5 is 0.5 pptv (2σ) for a 5 s integration, comparable to or better than previous measurements of NO3 (e.g., via DOAS), but with significantly better time resolution. Furthermore, direct measurement of N2O5 represent a previously unavailable capability. Concentrations of both species are measured simultaneously in two separate flow systems and optical cavities pumped by the same pulsed dye laser at 662 nm. One of the flow systems remains at ambient temperature for detection of NO3, while the other is heated to 80 °C to induce thermal decomposition of N2O5 providing a measurement of the sum of the NO3 and N2O5 concentrations. This article outlines a series of laboratory and field tests of the instrument’s performance. Important considerations include sig...
127 citations
TL;DR: In this paper, rate coefficient and product branching measurements for the reaction OH + bromopropane from 230 to 360 K were presented for a single-stage reaction with O(n 2 ).
Abstract: Article on rate coefficient and product branching measurements for the reaction OH + bromopropane from 230 to 360 K.
23 citations