2. Nuclear fuel consists of fuel pins that are stacks of uranium oxide or mixed uranium plutonium oxide (MOX) cylindrical ceramic pellets, with diameters of 8–15 mm, that are encapsulated in metallic tubes. The fuel pins are grouped together in fuel assemblies. Each fuel assembly can be handled as a single entity, thus simplifying the fuelling and defuelling of reactors and the subsequent handl...

Isotope-selective photodissociation of the volatile complex uranyl hexafluoroacetylacetonate . tetrahydrofuran [UO(2)(hfacac)(2) . THF] has been achieved with both a continuous-wave and a pulsed carbon dioxide laser. The photodissociation was carried out in a low-density molecular beam under collisionless conditions. Transitions of the laser are in resonance with the asymmetric O-U-O stretch of...

This article examines the production of metastable technetium-99 (Tc-99m), the world’s most important radiopharmaceutical, focusing on reliability of supply and risks of nuclear terrorism. Only four producers manufactured about 95 percent of the world’s Tc-99m; a closure of any of them could cause worldwide shortfalls. Moreover, all four employ highly enriched uranium in their production proces...

Reductive immobilization of uranium by the stimulation of dissimilatory metal-reducing bacteria (DMRB) has been investigated as a remediation strategy for subsurface U(VI) contamination. In those environments, DMRB may utilize a variety of electron acceptors, such as ferric iron which can lead to the formation of reactive biogenic Fe(II) phases. These biogenic phases could potentially mediate a...

The fundamental problem on which Ilya Prigogine and the BrusselsAustin Group have focused can be stated briefly as follows. Our observations indicate that there is an arrow of time in our experience of the world (e.g., decay of unstable radioactive atoms like Uranium, or the mixing of cream in coffee). Most of the fundamental equations of physics are time reversible, however, presenting an appa...

Radon prone houses are often associated with uranium-rich geologic formations, but these formations are difficult to predict in the absence of indoor radon measurements. Even with data, it may be difficult to specify a hot spot if the area does not conform with established administrative boundaries or if there is uncertainty to the specific test location due to confidentiality. Radon in soil ga...

UO2 is the standard nuclear fuel used in modern, conventional power reactors (e.g. PWR, BWR and AGR). The oxide phase of fissile uranium provides the necessary thermodynamic stability required in operating conditions. It then follows that an extensive knowledge of the properties of this material is necessary. Unfortunately, experimental research is costly, especially if fission products are con...

Oxidation–hydration weathering of uraninite, the most common U-bearing mineral in nature, comprises various physical and chemical processes that lead to the destruction of the fluorite-type structure of uraninite where U is present as tetravalent. This results in replacement of uraninite by weathering products containing U in hexavalent form, i.e. as uranyl ion, UO2 2+. The final assemblage of ...

Closed mines pose significant risks to the environment and human health. Uranium mine contamination of surface water, groundwater and soil have received moderate attention, but few studies have investigated dust transport of uranium. The latter has immediate implications for remediation efforts and environmental/human health regulators. Frequent dust storms intensify aeolian transport of uraniu...