The ependymal cells line the ventricles of the brain. They compose a thin lining along the brain's ventricle cell, and the central canal of spinal cord. They are a type of glial cells. They play an important role in the production of cerebrospinal fluid.
The fuel used in nuclear reactors is commonly uranium. Its unstable nature means that when it is hit with an electron it splits into two new atoms, one of which is Krypton. In the process of splitting large amounts of energy is released. This energy is used to heat water to produce steam, the steams rising energy is used to turn a turbine which produces the electric output of nuclear power stations.