It is based on the idea of a fission chain reaction moving through a core in a "wave."

These are materials that sustain an explosive fast fission chain reaction.

Producing a fission chain reaction in natural uranium fuel was found to be far from trivial.

To be a useful fuel for nuclear fission chain reactions, the material must:

The insertion of a single blade was sufficient to shut down the fission chain reaction.

That or a method of initiating a fission chain reaction in stable atoms."

However, if a sufficient quantity of uranium-235 could be isolated, it would allow for a fast neutron fission chain reaction.

This is high enough to permit a sustained nuclear fission chain reaction to occur, provided other supporting conditions exist.

Large-scale natural uranium fission chain reactions, moderated by normal water, had occurred far in the past and would not be possible now.

Fission chain reactions are generally driven by the amount of neutrons present (as products from previous fissions).

This causes a self-sustaining fission chain reaction.

In addition to laser enrichment, the university carried out a test on neutron generator that can also trigger the fission chain reaction.

The detonation seemed almost soundless, but the percussion of the fission chain reaction shook the mountain to its core.

Some of them produce neutrons, called delayed neutrons, which contribute to the fission chain reaction.

In practice, sustaining a fission chain reaction with fast neutrons means using relatively highly enriched uranium or plutonium.

Be in the region of the binding energy curve where a fission chain reaction is possible (i.e., above radium)

A subcritical mass is a mass of fissile material that does not have the ability to sustain a fission chain reaction.

Fission chain reactions occur because of interactions between neutrons and fissile isotopes (such as U).

"A fission chain reaction."

The chemical element isotopes that can sustain a fission chain reaction are called nuclear fuels, and are said to be fissile.

A fission chain reaction produces intermediate mass fragments which are highly radioactive and produce further energy by their radioactive decay.

The nuclear fission chain reaction became self-sustaining and began to emit intense gamma and neutron radiation.

The high explosives surrounding the core of the primary fire, compressing the fissile material into a supercritical state and beginning the fission chain reaction.

Too high of fuel temperatures can compromise the fuel, and therefore it is important to control the temperature in order to control the fission chain reaction.

If this coolant flow is reduced, or lost altogether, the nuclear reactor's emergency shutdown system is designed to stop the fission chain reaction.