Cycle per second operation. Thus, one becquerel is one event per second "on average", whereas one hertz is one event per second on a regular cycle. Cycle can also be a unit for measuring usage of reciprocating machines, especially presses, in which cases "cycle" refers to one complete revolution of the mechanism being measured (i.e. the shaft of a reciprocating engine). Cycle per second The cycle per second was a once-common English name for the unit of frequency now known as the hertz (Hz). The plural form was typically used, often written cycles per second, cycles/second, c.p.s., c/s, ~, or, ambiguously, just cycles.
Enzyme unit SI unit, the enzyme unit is discouraged in favour of the katal, the unit recommended by the General Conference on Weights and Measures in 1978 and officially adopted in 1999. One katal is the amount of enzyme that converts 1 mole of substrate per second, so The enzyme unit should not be confused with the international unit (IU); although it is true that both measure chemical activity and that for many enzymes 1 U = 1 IU (because for many enzymes the existing U was adopted as the newer IU), international units can be defined for the biologic activity of