A kilowatt-plus microwave-induced plasma (KiP-MIP) system was modified for better analytical performance. Modifications included the use of a redesigned plasma torch and a new plasma resonator cavity. The use of the redesigned plasma torch improved the detection of aqueous chloride by 2 orders of magnitude. With the redesigned plasma torch, the performance of the KiP-MIP utilizing the original 3-cm-depth and 2-cm-depth resonator cavities were studied. Results indicated that the KiP-MIP with the 2-cm-depth resonator cavity exhibited better characteristics in terms of plasma energy coupling, excitation characteristics, and determination of aqueous chloride.
Mingin Wu and Jon W. Carnahan, "Characteristics of a Kilowatt-Plus Helium Microwave-Induced Plasma Utilizing 2- and 3-cm-Depth TM010 Resonator Cavities," Appl. Spectrosc. 46, 163-168 (1992)