Determination of 36Cl in biological shield concrete using pyrohydrolysis and liquid scintillation counting.

A method for the determination of 36Cl in biological shield concrete of nuclear reactors was developed. Cl in the concrete sample was extracted quantitatively by pyrohydrolysis at 900 degrees C and recovered in Na2CO3 solution for subsequent measurement of 36Cl by liquid scintillation counting. WO3 was used as an accelerator in the pyrohydrolysis.

Determination of 41Ca in biological-shield concrete by low-energy X-ray spectrometry.

An X-ray spectrometric method has been developed for the determination of 41Ca in the biological-shield concrete of nuclear reactors. The concrete sample was first decomposed with nitric, hydrofluoric, and perchloric acids. Calcium was then separated from other radionuclides by ion-exchange chromatography and recovered as an oxalate precipitate.