Present status and perspective of radiochemical analysis of radionuclides in Nordic countries

Analyzing alpha emitting isotopes of Pu, Am and Cm from NPP water samples: an intercomparison of Nordic radiochemical laboratories

Radioanalytical methods for the determination of isotopes of Pu, Am and Cm in water samples from nuclear power plants were compared and further developed in a Nordic project (Optimethod) through two intercomparison exercises among Nordic laboratories. With this intercomparison, the analytical performance of some laboratories was improved by modification of the analytical method and adopting new techniques. The obtained results from the two intercomparisons for alpha emitting transuranium isotopes are presented, and the lessons learnt from these intercomparison exercises are discussed.

Dynamic Flow Approaches for Automated Radiochemical Analysis in Environmental, Nuclear and Medical Applications

Automated sample processing techniques are desirable in radiochemical analysis for environmental radioactivity monitoring, nuclear emergency preparedness, nuclear waste characterization and management during operation and decommissioning of nuclear facilities, as well as medical isotope production, to achieve fast and cost-effective analysis. Dynamic flow based approaches including flow injection (FI), sequential injection (SI), multi-commuted flow injection (MCFI), multi-syringe flow injection (MSFI), multi-pumping flow system (MPFS), lab-on-valve (LOV) and lab-in-syringe (LIS) techniques have been developed and applied to meet the analytical criteria under different situations. Herein an overall review and discussion on these techniques and methodologies developed for radiochemical separation and measurement of various radionuclides is presented. Different designs of flow systems with combinations of radiochemical separation techniques, such as liquid-liquid extraction (LLE), liquid-liquid microextraction (LLME), solid phase extraction chromatography (SPEC), ion exchange chromatography (IEC), electrochemically modulated separations (EMS), capillary electrophoresis (CE), molecularly imprinted polymer (MIP) separation and online sensing and detection systems, are summarized and reviewed systematically.

Isolation and quantification of a 93Mo isotope solution from proton irradiated niobium

⁹³Mo (4000 y half-life) formed through the ⁹³Nb(p,n)⁹³Mo reaction was isolated from a niobium target foil previously used in a low energy medical cyclotron. ⁹³Mo has identical characteristic x-ray emission and mass as the isomer ^93mNb and stable Nb present in the target foil at much higher concentrations. This makes distinction between ⁹³Mo, ^93mNb and stable Nb difficult using radiometric or mass spectrometric methods. An anion exchange method in combination with x-ray spectrometry and ICP-MS/OES enabled quantitative isolation of about 0.4 μg ⁹³Mo (14 kBq) from ^93mNb with a separation factor >10⁴ on a single column. An extraction chromatography column (TEVA) was used to reach a^93mNb/⁹³Mo activity ratio of <10^-6 and an atom ratio ⁹³Nb/⁹³Mo <1% making the ⁹³Mo suitable for both radiometric and mass spectrometric testing. ⁹³Mo is the only radioisotope of molybdenum with a long enough half-life suitable for this purpose. Calibration of the ⁹³Mo isotope solution was done through x-ray spectrometry using a characterized BEGe-detector in combination with a^99mTc solution. This is the first reported isolation of a⁹³Mo solution in the literature and the first time a LSC-spectrum of ⁹³Mo is shown.