Abstract: Both gadolinia nuclear fuel rods and urania fuel rods are non-destructively tested to determine the enrichment concentration of the fuel pellets therein by serially conveying the gadolinia rods and the urania rod along separate test channels through an active scanner where they are irradiated from a common neutron souce, and the neutron-induced gamma ray emissions are counted as a measure of the enrichment concentrations at a multiplicity of points distributed along the rod length. The enrichment counts are corrected for background radiation, variations in fuel density, and, in the case of gadolinia rods, for gadolinia content by passing these rods through a magnetometer.

Abstract: In a boiling water reactor nuclear plant, hydrogen is injected into the feed water to neutralize radiolysis which causes stress corrosion in stainless steel components. It has been discovered that by inhibiting volatile ammonia, and other gaseous nitrogen compounds from leaving the liquid phase portions of the plant to the steam phase portions of the plant, radiation is reduced to acceptable levels. Formation of ammonia is inhibited chemically, by altering the reaction paths for volatile nitrogen species with trace additives in the parts per billion range, suitable additives include nitrous oxide, copper, zinc, carbon dioxide, and other components. It has also been found that by manipulating the pH, the formation of the voltage nitrogen compounds, especially ammonia, is decreased. Similarly, by physically altering plant operating conditions to reduce sparging or scrubbing of the gases from areas of high radiation, confinement of the N-16 within the liquid phase of the plant within the reactor vessel occurs.

Abstract: Deposition of radioactive cobalt on the interior surfaces of a water-cooled nuclear reactor and intergranular stress corrosion cracking are inhibited or substantially prevented by the continuous injection of zinc oxide to the reactor water. The zinc oxide may be prepared in the form of a paste, a slurry, or a preformed aqueous solution.

Abstract: Both gadolinia nuclear fuel rods and urania fuel rods are non-destructively tested to determine the enrichment concentration of the fuel pellets therein by serially conveying the gadolinia rods and the urania rod along separate test channels through an active scanner where they are irradiated from a common neutron source, and the neutron-induced gamma ray emissions are counted as a measure of the enrichment concentrations at a multiplicity of points distributed along the rod length. The enrichment counts are corrected for background radiation, variations in fuel density, and, in the case of gadolinia rods, for gadolinia content by passing these rods through a magnetometer.

Abstract: Deposition of radioactive cobalt on the interior surfaces of a water-cooled nuclear reactor is inhibited or substantially prevented by the continuous injection of zinc oxide to the reactor water. The zinc oxide may be prepared in the form of a paste, a slurry, or a preformed aqueous solution.

Abstract: In water-cooled nuclear reactors where zinc is added to the water to remove or lessen the accumulation of radioactive cobalt, radioactivity arising from the zinc itself as a result of neutron capture is lessened or eliminated entirely by modifying the isotopic composition of the zinc prior to its injection into the system. The modification of the isotopic composition consists of lowering the proportion of .sup.64 Zn or removing this isotope entirely.

Abstract: A method is disclosed for controlling the release of radioiodine produced by the fission of uranium 235 during the process for the production of molybdenum 99. In the process for producing molybdenum 99, an aluminum-uranium alloyed target is irradiated with a neutron flux to bring about fission of the Uranium 235 producing molybdenum 99, radioiodine and other fission by-products. The method herein comprises reacting the irradiated target with a caustic solution. A reactive silver is then mixed with the caustic solution in an amount sufficient to react with substantially all of the radioiodine present in the caustic solution thereupon forming a silver precipitate of radioiodine. The precipitate formed is then separated from the caustic solution resulting in a substantially radioiodine-free caustic solution containing molybdenum 99.