Laser-Spectroscopic Measurements of the Free Radicals Produced from the Dissociation of C₂H₂ with the Microwave Discharge Flow of Ar

Abstract

C2(a 3 Πu) radicals were produced using the dissociative excitation reaction of C2H2 with the microwave discharge flow of Ar. The mechanism of the production of these radicals was investigated by a combined analysis of the laser-induced fluorescence spectroscopy of the C2(d 3 Πg−a 3 Πu) (Swan band) and Ar( 3 P1− 3 P0) transitions and the electrostatic-probe measurements. From the dependences of these LIF intensities and the kinetic-energy distribution of free electrons on the pressure of Ar, it was concluded that the mechanism of the production of C2(a 3 Πu) was the collisional energy transfer from the metastable state of Ar, Ar( 3 P0,2). This conclusion was supported by a chemical-kinetic analysis.

Plasma electrolytic liquefaction of cellulosic biomass

“…The line belonging to the C 2 Swan band system, corresponding to the d 3 Π g →a 3 Π u transition with Δν=0 is located at 516 nm [19]. The presence of •C 2 should correspond to the presence of C in the solid residue.…”

“…The :CH 2 and •CH 3 generated by the dehydrogenation of methane are usually difficult to measure because their emission spectra are not obvious (see reference[18]). The line belonging to the C 2 Swan band system, corresponding to the d 3 Π g →a 3 Π u transition with Δν=0 is located at 516 nm[19].…”