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Neptunium and americium speciation in selected basalt, granite, shale, and tuff ground waters

J.M. Cleveland·T.F. Rees·K.L. Nash
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Abstract

Neptunium and americium are relatively insoluble in ground waters containing high sulfate concentrations, particularly at 90°C. The insoluble neptunium species is Np(IV); hence reducing waters should enhance its formation. Americium can exist only in the trivalent state under these conditions, and its solubility also should be representative of that of curium.

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J.M. Cleveland, T.F. Rees, K.L. Nash. 1983. Neptunium and americium speciation in selected basalt, granite, shale, and tuff ground waters. https://doi.org/10.1126/science.221.4607.271

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