"0.375"^^ . . "uranium 238"@en-us . . . . . "uranium 238"^^ . . . . . "114660835"^^ . "113821576"@en-us . "14660835-n"^^ . "the commonest isotope of uranium; it is not fissionable but when irradiated with neutrons it produces fissionable plutonium 239"@en-us . "110506641"@en-us . . "0"^^ .