TY - JOUR
T1 - Emission characteristics of nickel ionic lines excited by reduced-pressure laser-induced plasmas using argon, krypton, nitrogen, and air as the plasma gas
AU - Nakamura, Shuya
AU - Wagatsuma, Kazuaki
N1 - Funding Information:
The authors gratefully acknowledge financial support by grants from The Iron and Steel Institute of Japan and by a grant from Steel Industry Foundation for the Advancement of Environment Protection Technology, Japan.
PY - 2007/12
Y1 - 2007/12
N2 - The emission characteristics of nickel ionic lines in low-pressure laser-induced plasmas are investigated when argon, krypton, nitrogen, or air gas was employed as the plasma gas. The spectrum patterns and the relative intensities of the ionic lines are measured with and without a blind cylinder surrounding the sample surface to separate the detected emission area into two portions roughly: an initial breakdown zone and an expansion zone of the plasma. Their emission intensities are strongly dependent on both the kind and the pressure of the plasma gas. Different major ionic lines are observed in the argon and the krypton plasmas: for example, the Ni II 230.010-nm line (8.25 eV) for argon and the Ni II 231.604-nm line (6.39 eV) for krypton. The excitation mechanism of these ionic lines is considered to be a resonance charge-transfer collision with argon or krypton ion due to good energy matching to the corresponding energy levels of nickel ion. These ionic lines measured with the blind cylinder at reduced pressures of around 1300 Pa give the largest signal-to-background ratios; therefore, the analytical application under such optimum plasma conditions is recommended.
AB - The emission characteristics of nickel ionic lines in low-pressure laser-induced plasmas are investigated when argon, krypton, nitrogen, or air gas was employed as the plasma gas. The spectrum patterns and the relative intensities of the ionic lines are measured with and without a blind cylinder surrounding the sample surface to separate the detected emission area into two portions roughly: an initial breakdown zone and an expansion zone of the plasma. Their emission intensities are strongly dependent on both the kind and the pressure of the plasma gas. Different major ionic lines are observed in the argon and the krypton plasmas: for example, the Ni II 230.010-nm line (8.25 eV) for argon and the Ni II 231.604-nm line (6.39 eV) for krypton. The excitation mechanism of these ionic lines is considered to be a resonance charge-transfer collision with argon or krypton ion due to good energy matching to the corresponding energy levels of nickel ion. These ionic lines measured with the blind cylinder at reduced pressures of around 1300 Pa give the largest signal-to-background ratios; therefore, the analytical application under such optimum plasma conditions is recommended.
KW - Atomic emission spectrometry
KW - Charge-transfer collision
KW - Excitation mechanism
KW - Low-pressure laser-induced plasma
KW - Nickel ionic lines
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U2 - 10.1016/j.sab.2007.10.008
DO - 10.1016/j.sab.2007.10.008
M3 - Article
AN - SCOPUS:36749075088
VL - 62
SP - 1303
EP - 1310
JO - Spectrochimica Acta - Part B Atomic Spectroscopy
JF - Spectrochimica Acta - Part B Atomic Spectroscopy
SN - 0584-8547
IS - 12
ER -