11. The Energy Department is considering importing about 24, 000 spent fuel elements from Europe. 12. The fuel element or assembly is arranged in an array of cells or bundles. 13. Pieces of the damaged fuel elements also fell to the bottom of the reactor. 14. The reactor kept experiencing technical difficulties, with fuel elements breaking more often than anticipated. 15. This differs from a fuel element failure, which is not caused by high temperatures. 16. The reactor core normally consists of 27 fuel elements , of about 30 kg of uranium. 17. The high-flux research reactor produces neutrons through fission in a specially designed, compact-core fuel element . 18. Also for use with solid fuel elements fluorine volatility is quite well developed and tested. 19. The Sodium Reactor Experiment reactor core contained forty-three fuel elements , each comprising seven fuel rods. 20. The reactor is high with a core in diameter and high, with 32 fuel elements .