226Radium

Bettoli et al. [ 17] has described a shipboard system to measure the concentrations of 222radium and 226radium in sea and coastal waters. 

Measurements of 226radium are simpler than those for 228radium and are more precise. These measurements are generally made by concentrating the radium from up to a few litres via barium sulfate precipitation followed by thick source a counting or by 222radon extraction following dissolution of barium sulfate [21]. 

The introduction of high-resolution, high-efficiency /-ray detectors composed of lithium-drifted germanium crystals has revolutionised /-measurement techniques. Thus, /-spectrometry allows the rapid measurement of relatively low-activity samples without complex analytical preparations. A technique described by Michel et al. [25] uses Ge(Li) /-ray detectors for the simultaneous measurements of 228radium and 226radium in natural waters. This method simplifies the analytical procedures and reduces the labour while improving the precision, accuracy, and detection limits. 

Spectrophotometric analysis following extraction with Aliquot 336 has been used to determine uranium in seawater [108]. Kim and Burnett [109] used X-ray spectrometry to determine the uranium series nucleides including 238uranium, 226radium and 210lead in marine phosphorites. 

Various workers have discussed methods for the determination of 226radium in soils [8,9]. 

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