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AbstractUranium hydride is commonly used to store hydrogen or its isotopes in a solid state. The Self-Assaying Tritium Accountancy and Containment Unit for ITER (STACI) is a 5.2-kg bed of depleted uranium (dU) capable of holding up to 33 mol of hydrogen or its isotopes. This paper is a summary of data analysis of past experimental campaigns with STACI, with the aim of describing the kinetics and thermodynamics of the hydriding process. Computed tomography imaging was performed on STACI both before and after its experimental campaign, and a high degree of swelling was observed in the dU. Literature on studies in regard to the swelling of large (multikilogram) quantities of uranium hydride for storage applications was not identified during this study. Data from the experimental campaign, as well as data on the formation reaction, are presented. The authors hope to create an analytical model of STACI based on these data.

Traditionally the amount of tritium on a surface is determined by swiping the surface with a material such as filter paper and counting the removed tritium by scintillation. While effective, this method can be time consuming, can alter the surface, only measures removable tritium and produces radioactive waste. For a given application each of these considerations may or may not be a disadvantage. A solid state monitor, on the other hand, has the potential to provide rapid analysis, not alter the surface, measure all tritium on a surface and produce little or not radioactive waste. This allure has promoted open wall ion chamber and PIN diode-based tritium surface monitor development, and these techniques have enjoyed certain success. Recently the first tests were performed with an avalanche photodiode (APD) for surface tritium measurement. While quite similar in concept to PIN diode based measurements, side-by-side testing showed that the APD provided substantially better counting efficiency. Considerations included count rate, background, sensitivity, stability and effect of ambient light. Of particular importance in the US, the APD was able to measure concentrations down to the “free release” limit, i.e., the concentration below which items can be removed from radiological control areas.

Biomolecular interaction analysis (BIA) which utilizes surface plasmon resonance (SPR) detection of affinity-captured analytes has been interfaced with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI). Femtomole quantities of a peptide, myotoxina,were detected by direct MALDI analysis of sensor chips used during BIA of a polyclonal anti-myotoxinaIgG/myotoxinasystem. Further, different interactive surfaces (flow cells) present on a single biosensor were targeted individually for mass spectrometric analysis. System compatibility of the combined approach was demonstrated with sensitivities, detection limits, and analytical performances comparable to those intrinsic to the individual analyses. The combined approach unites the real-time capabilities of SPR-based BIA with the qualitative specificity of mass spectrometry.