Chemical properties
Oxygen is used in medical emergencies mainly to take advantage of the chemical properties of oxygen, which is used in medical emergencies to participate in respiration in the body, which is a slow oxidizing process. Oxygen is a monomer formed by the element oxygen, which is chemically active.
In the steelmaking process blowing high purity oxygen, oxygen and carbon and phosphorus, sulfur, silicon and other oxidation reaction, which not only reduces the carbon content of steel, but also conducive to the removal of phosphorus, sulfur, silicon and other impurities. And the heat generated in the oxidation process is enough to maintain the temperature required for the steelmaking process, therefore, oxygen blowing not only shortens the smelting time, while improving the quality of steel. In blast furnace ironmaking, increasing the oxygen concentration in the blast air can reduce the coke ratio and increase the output. In non-ferrous metal smelting, the use of oxygen-enriched can also shorten the smelting time to improve production.
Oxygen is very active and can react with many substances, but not all substances can react with oxygen. Substances burn more violently in oxygen than in air because: the relatively small amount of oxygen in the air, oxygen has a flammable, oxidizing, but not flammable.
Burning does not necessarily produce a flame, as in the case of iron, aluminum, and carbon. Iron wire should be polished with sandpaper to remove rust, the purpose of winding iron wire into a spiral is to increase the contact surface with oxygen, which helps to increase the local temperature of the wire, a match should be used to ignite the wire, and the collecting cylinder should be filled with a small amount of water or fine sand to prevent splashes of high-temperature molten material from blowing the bottom of the bottle.
Oxygen has a very wide range of uses. Mainly supply respiration, support combustion and reaction exothermic three aspects
1, supply respiration: in general, respiration only need air. But in the lack of oxygen, low oxygen or oxygen-free environment, such as: diving operations, mountaineering, high-altitude flight, cosmic navigation, medical rescue, etc., often need to use oxygen.
2, support for combustion: In general, combustion requires only air. But in some need for high temperature, rapid combustion and other special requirements, such as blast ironmaking, converter steelmaking, etc., the need to use oxygen-enriched air or oxygen.
3, reaction exothermic: oxidation reaction, especially combustion reaction, the release of a large number of heat can be utilized. For example, coal heating, thermal power generation; industrial use of acetylene (C2H2) in oxygen combustion oxyacetylene flame to weld or cut metal, oxyacetylene flame can produce more than 3000 ℃ high temperature.
People also use liquid oxygen impregnated with wood chips, charcoal powder and other porous material made of liquid oxygen explosives, used for rock-cutting, trenching and mining and other open-air engineering blasting. In addition, oxygen (air) is also the production of sulfuric acid, nitric acid and other chemical products raw materials.
Excessive oxygen intake also promotes life aging. Oxygen into the human body and cell oxidizing enzyme reaction, can generate hydrogen peroxide, and then into lipofuscin. This lipofuscin is to accelerate cellular aging of harmful substances, it accumulates in the myocardium, so that cardiomyocyte aging, cardiac function decline; accumulates in the blood vessel wall, resulting in aging and hardening of blood vessels; accumulates in the liver, weakening the liver function; accumulates in the brain, causing intellectual decline, memory loss, the person becomes demented; accumulates in the skin, the formation of age spots.