High-assay low enriched uranium

Uranium enriched to 5…20 percent U-235

Heat transfer device using phase transition

Deuterium monoxide

Water whose hydrogen atoms are all deuterium isotopes

Heavy-water pressurised reactor

Primary heat transport: D2O (heavy) water

High-temperature gas-cooled reactor

Primary heat transport: helium gas

High temperature gas cooled reactor

Fuel assembly arrangement in hexagon form

HTGR fuel element form consisting of movable spherical elements

The fuel elements of tennis-ball size are called pebbles

HTGR fuel element form consisting of prismatic blocks

Primary heat transport: helium gas

High-temperature gas-cooled fast reactor

Primary heat transport: helium gas

HTGR fuel element form consisting of movable spherical elements

The fuel elements of tennis-ball size are called pebbles