Tin per kg over years: In 2006, about half of all tin produced was used in solder. The rest was divided between tin plating, tin chemicals, brass and bronze alloys, and niche uses. Tin has long been used in alloys with lead as solder, in amounts 5 to 70% w/w. Tin with lead forms a eutectic mixture at the weight proportion of 61.9% tin and 38.1% lead (the atomic proportion: 73.9% tin and 26.1% lead), with melting temperature of 183 °C (361.4 °F) . Such solders are primarily used for joining pipes or electric circuits. Since the European Union Waste Electrical
C-element C-element The Muller C-element (C-gate, hysteresis flip-flop, or sometimes coincident flip-flop, two-hand safety circuit) is a small digital block widely used in design of asynchronous circuits and systems. It has been specified formally in 1955 by David E. Muller and first used in ILLIAC II computer. In terms of the theory of lattices, the C-element is a semimodular distributive circuit, whose operation in time is described by a Hasse diagram. The C-element is closely related to the "rendezvous" and "join" elements, where an input is not allowed to change twice in succession. In some cases, when relations between delays are