“…The discharge arc pre-ionizes the sample surface before the pulsed laser reaches the sample surface, and intensies the lattice vibration, thereby reducing the laser excitation threshold. 37 In addition, the TCD can cause an increase in the sample temperature, reduce the reectivity of the sample surface, 38 increase the coupling efficiency between the sample and the pulsed laser, and increase the ablation mass of the sample, resulting in an enhancement in spectral intensity. 38,39 3.2 Effect of discharge length molecular bands have the same trend as Al(I) 396.1 nm and AlO (0-0).…”