It either must be enriched—made more concentrated in a rare form of uranium (U-235)—or converted into plutonium (Pu-239). Heavy water can play a role in breeding weapons-grade plutonium from ...

Breeder reactors like EBR-I were designed to transform uranium-238 into plutonium-239, a fissionable material. This transformation required a sophisticated sequence of nuclear reactions.

The very first stage of the nuclear program makes use of natural uranium to fuel the Pressurized Heavy Water Reactors to generate electricity. As a by-product, Plutonium-239 would be produced.

that the periods which have been ascribed to elements beyond uranium are also due to light elements. From the chemical evidence, the two short periods (10 sec. and 40 sec.) so far ascribed to 239 ...