high energy (fast) neutrons alone

low energy (slow) neutrons alone

either fast or slow neutrons

medium energy neutrons

regenerative reactor

fast breeder reactor

breeder reactor

boiling water reactor

is lighter

is inert

has high specific heat

is a good conductor

99.282% U238, 0.712% U235, 0.006% U234

99.282% U235, 0.712% U238, 0.06%′ U234

99.282% U234, 0.712% U238, 0.006% U235

99.282% U235, 0.712% U234, 0.006% U238

pressurised water

boiling water

gas cooled

liquid metal cooled