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A combustion light-gas gun (CLGG) is a projectile weapon that utilizes the explosive force of low molecular-weight combustible gases, such as hydrogen mixed with oxygen, as propellant. When the gases are ignited, they burn, expand and propel the projectile out of the barrel with higher efficiency relative to solid propellant and have achieved ...
Most notably, during the Holocaust large-scale gas chambers designed for mass killing were used by Nazi Germany from the late 1930s, as part of the Aktion T4, and later for its genocide program. More recently, escapees from North Korea have alleged executions to have been performed by gas chamber in prison camps, often combined with medical ...
Most nations use rapid-fire cannon on light vehicles, replacing a more powerful, but heavier, tank gun. A typical autocannon is the 25 mm "Bushmaster" chain gun, mounted on the LAV-25 and M2 Bradley armoured vehicles. Autocannons may be capable of a very high rate of fire, but ammunition is heavy and bulky, limiting the amount carried.
The slower-burning deflagration action results in a characteristic fragmentation pattern with large pieces dispersed in a 30-degree cone. [4] The Mk 211 is a very popular .50 caliber sniper round used in the Barrett M82 rifle and other .50 BMG rifles. [5] It is also often used in heavy machine guns such as the M2 Browning, but not the M85.
Often in chemical rocket engines, a higher molecular mass substance is included in the fuel to provide more reaction mass. Rocket propellant may be expelled through an expansion nozzle as a cold gas, that is, without energetic mixing and combustion, to provide small changes in velocity to spacecraft by the use of cold gas thrusters , usually as ...
Hypergolically-fueled rocket engines are usually simple and reliable because they need no ignition system. Although larger hypergolic engines in some launch vehicles use turbopumps, most hypergolic engines are pressure-fed. A gas, usually helium, is fed to the propellant tanks under pressure through a series of check and safety valves.
Some contact explosives contain an oxidizer and a fuel in their composition. [6] Chemicals like gasoline, a fuel, burn instead of explode because they must come into contact with oxygen in the combustion reaction. However, if the compound already contains both the oxidant and fuel, it produces a much faster and violent reaction.
The gaseous state of water is lighter than air (density 0.804 g/L at STP, average molecular mass 18.015 g/mol) due to water's low molar mass when compared with typical atmospheric gases such as nitrogen gas (N 2). It is non-flammable and much cheaper than helium. The concept of using steam for lifting is therefore already 200 years old.