Abstract
The authors used a plasma jet generator proposed by M. Yamamoto. It consists of a nozzle-shaped copper anode and a tungsten rod cathode containing 2% thoria, and uses argon as discharging gas. Fundamental studies were done on the determination of nickel, manganese and chromium in aqueous solution. Current 280A, flow rate of argon 15l/min., feeding rate of sample solution 1ml/min. and time of exposure about 10 seconds were most favorable. Comparison of the results with those by alternating arc discharge indicated that (1) the plasma jetmethod gave much higher linearity of calibration line, and (2) it was less affected by co-existing elements. In the case of aqueous solution, however, the background values due to water itself is so large that the sensitivity of detection of minute components by plasma jet excitation was not always higher than that by alternating arc excitation.
