As part of the preparation and calibration of three new National Institute of Standards and Technology (NIST) tritiated-water radioactivity Standard Reference Materials (SRMs), we have performed a comprehensive review and critical evaluation of the half-life of tritium (hydrogen-3). Twenty three experimentally-determined values of the half-life of tritium, reported between 1936 and 2000, were f...

(R)and (S)-Z-deuteriopropionyl coenzyme A of approximately 75% optical purity were prepared by a series of reactions starting from optically pure alanine. With these compounds as substrates for propionyl-CoA carboxylase, the deuterium isotope effect was found to be small and probably secondary. No tritium isotope effect was observed when enzymatically prepared 2-3H-propionyl-CoA was used as sub...

A sensitive tritium exchange assay was applied to the Rhizobium system for measuring the expression of uptake hydrogenase in free-living cultures of Rhizobium japonicum. Hydrogenase was detected about 45 hours after inoculation of cultures maintained under microaerophilic conditions (about 0.1% O(2)). The tritium exchange assay was used to screen a variety of different strains of R. japonicum (...

A 2-kJ Mather plasma focus device is used to deuterate the top end surface (or tip) of its central titanium electrode to investigate the occurrence of anomalous nuclear reactions in the context of the “cold fusion” phenomenon. The tip of the central titanium electrode is found to develop at least a few tens of microcuries of tritium after several plasma focus discharges. Neither the tritium imp...

Deuterium- and tritium-labeled pharmaceutical compounds are pivotal diagnostic tools in drug discovery research, providing vital information about the biological fate of drugs and drug metabolites. Herein we demonstrate that a photoredox-mediated hydrogen atom transfer protocol can efficiently and selectively install deuterium (D) and tritium (T) at α-amino sp3 carbon-hydrogen bonds in a single...

A conceptually simple first wall (FW) and blanket design for an inertial fusion system based on utilizing mobile FW tiles is presented. Using these tiles that are periodically removed, annealed, and reinstalled, tritium retention and surface erosion concerns for inertial fusion FW could be mitigated. A conceptual configuration has been developed with consideration for laser beam port accommodat...

The MISTRAL code was used to analyze the BEATRIX-II experimental results of Li,O ring samples. The analysis included the change in inventory due to different temperature transients, the end-of-life inventory of the Phase I ring sample, and the analysis of the transient tritium release history of both Phase I and Phase II ring samples. The change in inventory results were used in order to obtain...

Although early studies of streamwater residence time included the use of stable isotopes (deuterium, oxygen-18) and tritium, work in the last decades has largely relied on stable isotopes (or chloride) alone for residence time determination, and derived scaling relations at the headwater and mesoscale watershed scale. Here, we review critically this trend and point out a significant issue in ou...

For liquid breeder blanket system using molten salts, tritium barrier, anti-corrosion barrier, tritium recovery system and heat exchanger make important roles. Especially in the heat exchanger, the tritium permeation from primary coolant loop to secondary coolant loop must be inhibited by the tritium barrier for safety. To develop it, it is essential to optimize chemical stability of the barrie...

The robust nucleus of the archistriatum (RA) is one of the forebrain nuclei that control song production in birds. In the zebra finch (Poephila guttata), this nucleus contains more and larger neurons in the male than in the female. A single injection of tritiated thymidine into the egg on the 6th or 7th day of incubation resulted in labeling of many RA neurons with tritium. The size of tritium-...