Architectural glass percent of the world's flat glass is produced by the float glass process invented in the 1950s by Sir Alastair Pilkington of Pilkington Glass, in which molten glass is poured onto one end of a molten tin bath. The glass floats on the tin, and levels out as it spreads along the bath, giving a smooth face to both sides. The glass cools and slowly solidifies as it travels over the molten tin and leaves the tin bath in a continuous ribbon. The glass is then annealed by cooling in an oven called a lehr. The finished product has near-perfect
Lead-cooled fast reactor include fertile uranium as a metal, metal oxide or metal nitride. Smaller capacity LFR (such as SSTAR) can be cooled by natural convection, while larger designs (such as ELSY) use forced circulation in normal power operation, but with natural circulation emergency cooling. The reactor outlet coolant temperature is typically in the range of 500 to 600 °C, possibly ranging over 800 °C with advanced materials for later designs. Temperatures higher than 800 °C are high enough to support thermochemical production of hydrogen. The concept is generally very similar to sodium-cooled fast reactor, and most liquid-metal reactors have used sodium instead