The chemical element isotopes that can sustain a fission chain reaction are called nuclear fuels, and are said to be " fissile ".
12.
One of the key elements in the proper operation of a nuclear weapon is initiation of the fission chain reaction at the proper time.
13.
Too high fuel temperatures can compromise the fuel, and therefore it is important to control the temperature in order to control the fission chain reaction.
14.
But the explosive effects of nuclear fission chain reactions can be reduced by using substances like moderators which slow down the speed of secondary neutrons.
15.
In order to achieve an effective fission chain reaction, the neutrons produced during fission must be captured by fissionable nuclei, which then split, releasing more neutrons.
16.
The U . S . Energy Department says the test did not violate the treaty because no nuclear fission chain reaction occurred, producing no nuclear explosion.
17.
A "'fast neutron reactor "'or simply a "'fast reactor "'is a category of nuclear reactor in which the fission chain reaction is sustained by fast neutrons.
18.
However, such explosions do not happen during a chain reaction, but rather as a result of energy from radioactive beta decay, after the fission chain reaction has been stopped.
19.
The G-III model was superior to nuclear fission chain reaction experiments that had been conducted at the KWIP in Berlin-Dahem, the University of Heidelberg, or the University of Leipzig.
20.
On 11 March at 14 : 46 JST, Unit 1 scrammed ( shut off power-producing nuclear fission chain reactions ) successfully in response to the earthquake though evacuated workers reported violent shaking and burst pipes within the reactor building.
