Related Experiment Video
Updated: Aug 17, 2026

Enabling Real-Time Compensation in Fast Photochemical Oxidations of Proteins for the Determination of Protein Topography Changes
Published on: September 1, 2020
Diode-laser-based ultraviolet-absorption sensor for high-speed detection of the hydroxyl radical
Thomas N Anderson1, Robert P Lucht, Terrence R Meyer
1School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette, Indiana 47907, USA. tanderson@purdue.edu
Abstract:
A new diode-laser-based UV-absorption sensor for high-speed detection of the hydroxyl radical (OH) is described. The sensor is based on sum-frequency generation of UV radiation at 313.5 nm by mixing the output of a 763-nm distributed-feedback diode laser with that of a 532-nm high-power, diode-pumped, frequency-doubled Nd:YVO4 laser in a beta-barium borate crystal. Approximately 25 microW of UV radiation is generated and used to probe rotational transitions in the A2 Sigma+ -X2II (v' = 0, v" = 0) electronic transition of OH. Single-sweep, single-pass measurements of temperature and OH concentration in a stoichiometric C2H4-air flame are demonstrated at rates up to 20 kHz.
