Kjr. Weiland et al., LASER-INDUCED FLUORESCENCE DETECTION STRATEGIES FOR SODIUM ATOMS AND COMPOUNDS IN HIGH-PRESSURE COMBUSTORS, Applied optics, 32(21), 1993, pp. 4066-4073
A variety of laser-induced fluorescence schemes were examined experime
ntally in atmospheric pressure flames to determine their use for sodiu
m atom and salt detection in high-pressure, optically thick environmen
ts. Collisional energy transfer plays a large role m fluorescence dete
ction. Optimum sensitivity, at the parts in 10(9) level for a single l
aser pulse, was obtained with the excitation of the 4p-3s transition a
t 330 nm and the detection of the 3d-3p fluorescence at 818 nm. Fluore
scence loss processes such as ionization and amplified spontaneous emi
ssion were examined. A new laser-induced atomization/laser-induced flu
orescence detection technique was demonstrated for NaOH and NaCl. A 24
8-nm excimer laser photodissociates the salt molecules present in the
seeded flames prior to atom detection by laser-induced fluorescence.