title: Measurement of nitric oxide concentrations in flames by using electronic-resonance-enhanced coherent anti-Stokes Raman scattering.
abstract: We have measured nitric oxide (NO) concentrations in flames by using electronic-resonance-enhanced coherent anti-Stokes Raman spectroscopy (ERE-CARS). Visible pump and Stokes beams were tuned to a Q-branch vibrational Raman resonance of NO. A UV probe beam was tuned into resonance with specific rotational transitions in the (v"=1,v'=0) vibrational band in the A(2)Sigma(+)-X(2)Pi electronic transition, thus providing a substantial electronic-resonance enhancement of the resulting CARS signal. NO concentrations were measured at levels down to 50 parts in 10(6) in H(2)/air flames at atmospheric pressure. NO was also detected in heavily sooting C(2)H(2)/air flames at atmospheric pressure with minimal background interference.
authors.affiliation: School of Mechanical Engineering, Purdue University, West Lafayette, Indiana 47907, USA. wkulatil@purdue.edu
authors.forename: Waruna D
authors.initials: WD
authors.lastname: Kulatilaka
authors.forename: Ning
authors.initials: N
authors.lastname: Chai
authors.forename: Sameer V
authors.initials: SV
authors.lastname: Naik
authors.forename: Normand M
authors.initials: NM
authors.lastname: Laurendeau
authors.forename: Robert P
authors.initials: RP
authors.lastname: Lucht
authors.forename: Joel P
authors.initials: JP
authors.lastname: Kuehner
authors.forename: Sukesh
authors.initials: S
authors.lastname: Roy
authors.forename: James R
authors.initials: JR
authors.lastname: Gord