Direct current (dc) and radio frequency (rf) glow discharge power control requirements, and limitations are described. The differences between dc and rf power control are explored. The various difficulties faced with rf power regulation are listed and explained. In light of these challenges, the appropriate design goals for an rf glow discharge power supply and control system are outlined. The design and implementation of such a new rf design is then detailed. The ability of this new design to deal with the various rf difficulties is discussed. This design is evaluated and experimental evidence that it functions as anticipated is collected, presented, and discussed. This new rf power supply design is shown to have significant new capabilities.

A new technique is evaluated for normalizing laser power fluctuations in laser-ablation atomic spectrometry. The technique involves measuring the light loss caused by scattering from the ablated material as it flows through a specially designed cell. The resulting measured optical density can be used to correct for variations in the amount of sample that has been ablated. This new approach is compared to the use of a matrix element as an internal standard. Three different excitation sources for AES (Ar-ICP, Ar-MIP, and He-MIP) were combined with laser ablation and evaluated with the new normalization approach. Although the overall performance is best for the Ar-ICP combination, the MIPs have some desirable characteristics (i.e., low background radiation) which in some cases lead to better results. The spectra were collected with a photodiode-based spectrometer that is designed for simultaneous multichannel detection and is therefore especially well suited to measurement and background correction of signals produced during transient sampling such as with laser ablation. The ability of such a spectrometer to deal with complex samples such as cast iron is discussed.

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A new and inexpensive batch-type ultrasonic nebulizer which is based on a common room humidifier has been developed. The aerosol generation rate is shown to be much higher than that of pneumatic nebulizers and hence the detection capabilities of ICP and microwave plasma-AES are significantly enhanced when they are combined with this new nebulization system. Under optimal conditions the stability and precision of the system are comparable with those of commercial ultrasonic nebulizers.

Inductively coupled plasma mass spectrometry (ICP‐MS) has become the technique of choice for trace elemental analysis recently. Much work has focused on direct solid‐sample introduction techniques for ICP‐MS, with laser ablation (LA) showing the most promise. Photographs taken of the LA craters are used to demonstrate independent optimization of the ablation event. The type of optimization used will depend on the individual analysis requirements. An axial time‐of‐flight (TOF) mass spectrometer is used in conjunction with the ICP for the direct analysis of metals. Using this combination, inhomogeneities of specific trace metals (Nd, Zr, and Ta) in certified standard reference materials were found, while other metals remained homogeneous. These results are confirmed using steady‐state scanning of the sample and individual spot analysis.