Abstract: A neutron amplifier assembly of the invention includes an array of fissile material which is subjected to a primary neutron flux. According to the invention a thin layer of fissile material is located on the inner surface of a hollow support cylinder of moderator material, the diameter of the cylinder being chosen such that the array is close to criticality.

Abstract: A method of incineration of minor actinides in nuclear reactors is presented. The minor actinides to be incinerated are embedded in at least one finite region of a core of a thermal nuclear reactor. This finite region is isolated from the rest of the core by means of a thin layer of material that absorbs thermal neutrons but is transparent to fast neutrons. This isolating material is preferably fissile, so that the neutron flux in the core is not simply filtered of its thermal neutrons, but also amplified in its fast neutrons.

Abstract: This invention relates to a method for the destruction of plutonium (Pu) by irradiation in a light water reactor (LWR). According to the invention Pu is mixed with highly enriched uranium (U) in roughly equal weight proportion rates. This mixture is embedded in an inert matrix of a material whose components have an atomic number significantly lower than 92. LWR fuel pins are then produced therefrom and these pins are inserted in a LWR in place of certain normal LWR fuel pins. The irradiation time of the fuel pins containing Pu is significantly longer than that of said normal pins. The irradiation is preferably repeated after about 200 years without any reprocessing of the spent fuel.