U235sisällön

U235sisällön refers to the enrichment level of uranium, specifically the percentage of the fissile isotope uranium-235 (U-235) present in a given sample of uranium. Natural uranium consists of approximately 0.72% U-235 and the rest is predominantly uranium-238 (U-238). For use in most nuclear reactors and for weapons purposes, this concentration of U-235 needs to be increased.

The process of increasing the concentration of U-235 is called uranium enrichment. This is a complex and energy-intensive process because the physical and chemical properties of U-235 and U-238 are very similar. The primary methods used for enrichment are gaseous diffusion and gas centrifugation. Gaseous diffusion relies on the slight difference in mass between U-235 and U-238, allowing lighter U-235 hexafluoride gas to diffuse through a porous barrier slightly faster. Gas centrifugation utilizes centrifugal force to separate the isotopes based on their mass.

The required U235sisällön varies depending on the intended application. Low-enriched uranium (LEU) typically has a U-235 content of between 3% and 5%, which is used as fuel in most nuclear power reactors. Highly enriched uranium (HEU) has a U-235 content of 20% or more, and is used in some research reactors and in nuclear weapons. Uranium enriched to 90% U-235 or higher is considered weapons-grade. The control and monitoring of U235sisällön is a crucial aspect of nuclear non-proliferation efforts.