Ozone layer called the ozone-oxygen cycle. Chemically, this can be described as: About 90 percent of the ozone in the atmosphere is contained in the stratosphere. Ozone concentrations are greatest between about , where they range from about 2 to 8 parts per million. If all of the ozone were compressed to the pressure of the air at sea level, it would be only thick. Although the concentration of the ozone in the ozone layer is very small, it is vitally important to life because it absorbs biologically harmful ultraviolet (UV) radiation coming from the sun. Extremely short or vacuum UV (10–100
Compacted oxide layer glaze Compacted oxide layer glaze Compacted oxide layer glaze describes the often shiny, wear-protective layer of oxide formed when two metals (or a metal and ceramic) are slid against each other at high temperature in an oxygen-containing atmosphere. The layer forms on either or both of the surfaces in contact and can protect against wear. A not often used definition of "glaze" is the highly sintered compacted oxide layer formed due to the sliding of either two metallic surfaces (or sometimes a metal surface and ceramic surface) at high temperatures (normally several hundred degrees Celsius) in oxidizing conditions. The sliding or