The fate of the OH radical in molecular beam sampling experiments

New analytical tools for advanced mechanistic studies in catalysis: photoionization and photoelectron photoion coincidence spectroscopy

“…Stable reactants and products may be backscattered to the ionization region, while fleeting intermediates may be lost to wall collisions quantitatively. 58 Depending on the alignment of the source and the pumping conditions, 10-75% of the ion signal can be due to re-thermalized sample, and wall losses can skew the observed signal intensities towards the stable species. Therefore, it is advantageous to be able to tell apart neutrals directly emanating from the reactor from thermal background.…”

Isomer-sensitive characterization of low temperature oxidation reaction products by coupling a jet-stirred reactor to an electron/ion coincidence spectrometer: case of n-pentane

“…This analytical method has been only recently applied to combustion studies such as flames but its application is fast spreading and has already succeeded in detecting reactive intermediates and final products. [35][36][37][38][39][40][41] In this work we performed for the first time a PEPICO spectroscopy analysis during the oxidation in a Jet-Stirred Reactor (JSR) of n-pentane, the simplest alkane presenting a lowtemperature reactivity really representative of that of heavier fuels present in gasolines and Diesel fuels. For this reason, the oxidation of this C5 saturated hydrocarbon has been thoroughly experimentally investigated with reliable detailed kinetic modeling.…”

Combustion in the future: The importance of chemistry

“…Because of their widespread use for (full) speciation measurements, it is necessary to keep in mind that probe perturbations can significantly affect temperature and species profiles [281] , [282] , [283] , [284] , [285] , [286] , [287] . Sampling techniques may influence the detection of important combustion intermediates such as the OH radical [286] , and they might contribute to the formation of low-temperature intermediates via cooling effects [287] . As clearly demonstrated by Hansen et al [281 , 282] , probe perturbations in flat laminar premixed flames are typically not one-dimensional.…”