An improved plasma jet system for spectrochemical analysis

Abstract

The stability of a plasma jet has been improved by replacing the direct-injection nebuliser with a pre-mixed chamber-nebuliser arrangement of the type used in flame spectrometry. This arrangement has alleviated many of the operational problems that were experienced with the original system. As a result of the improved performance, the unit can be operated in conjunction with instantaneous photoelectric read-out. Details of the modification are given and the stability obtained is demonstrated. The sensitivity of the modified plasma jet has been investigated and detection limits for the most sensitive lines of sixty-seven elements are presented. These detection limits are compared with those obtained by using a nitrous oxide-acetylene flame with the same optical arrangement and detection equipment.