Reducing atmosphere that sodium is reduced and evaporated to produce the sodium tail of the Moon (see atmosphere of the Moon). Reducing atmosphere A reducing atmosphere is an atmospheric condition in which oxidation is prevented by removal of oxygen and other oxidizing gases or vapours, and which may contain actively reducing gases such as hydrogen, carbon monoxide, and gases such as hydrogen sulphide that would be oxidized by any present oxygen. In metal processing, a reducing atmosphere is used in annealing ovens for relaxation of metal stresses without corroding the metal. A non oxidizing gas, usually nitrogen, is used, or for more
Gas-operated reloading piston has traveled a short distance. Most systems, however, vent excess gas into the atmosphere through slots, holes, or ports. A gas trap system involves 'trapping' combustion gas as it leaves the muzzle. This gas impinges on a surface that converts the energy to motion that, in turn cycles the action of the firearm. Hiram Maxim patented a muzzle-cup system in 1884 described in though it is unknown if this firearm was ever prototyped. John Browning used gas trapped at the muzzle to operate a 'flapper' in the earliest prototype gas-operated firearm described in . The Danish Bang rifle used