Figure 4. A matrix of the IP read-out images, to show the desorption feature of ¹³⁷Cs from (top) WB and (bottom) SWa-1 using various electrolyte solutions.

Initially ¹³⁷Cs was sorbed to the mineral particles from a 50 μL solution with 1.85 Bq for one day. The elution was performed by immersing the substrates in the electrolyte solutions (50 μL) for one day. The figure at the bottom of each image represents the percentage of ¹³⁷Cs remaining in the mineral particles after the immersion.