Actinides and Other Alpha-Emitters, Determination of
Published Online: 15 SEP 2006
Copyright © 2000 John Wiley & Sons, Ltd. All rights reserved.
Encyclopedia of Analytical Chemistry
How to Cite
Vintró, L. L. and Mitchell, P. I. 2006. Actinides and Other Alpha-Emitters, Determination of. Encyclopedia of Analytical Chemistry. .
- Published Online: 15 SEP 2006
To assay an actinide or other α-emitter at the low concentrations encountered in many environmental samples necessitates chemical separation of the actinide of interest from the bulk matrix, purification by the elimination of other interferants, mounting onto a suitable substrate for counting, and quantification by radiometric, mass spectrometric or other means. In this contribution, the chain of analysis from sampling to counting is critically reviewed and many of the most important pitfalls and sources of error are highlighted. Specifically, the pretreatment, preconcentration, separation and purification steps required for the assay of thorium, uranium, neptunium, plutonium, americium and curium in a wide range of environmental matrices are examined in detail. Emphasis is given to the need for appropriate radiochemical yield monitors and to the practical application of ion exchange, solvent extraction and extraction chromatography in the purification of these elements. This is complemented by a description of methods for the preparation of quality sources suitable for counting by α-spectrometry, liquid scintillation α-spectrometry and mass spectrometry. In addition, an overview is given of the operational principles and systems used in α-radiometry and mass spectrometry, including a discussion of the practical limits of detection and quantitation achievable with these systems. Finally, the importance of traceability and good quality assurance in precision actinide assay is emphasized.