Atmosphere of Earth they penetrate more deeply. The various layers of Earth's ionosphere, important to HF radio propagation, begin below 100 km and extend beyond 500 km. By comparison, the International Space Station and Space Shuttle typically orbit at 350–400 km, within the F-layer of the ionosphere where they encounter enough atmospheric drag to require reboosts every few months. Depending on solar activity, satellites can experience noticeable atmospheric drag at altitudes as high as 700–800 km. The division of the atmosphere into layers mostly by reference to temperature is discussed above. Temperature decreases with altitude starting at sea level, but variations in this
Atmospheric-pressure plasma to coat varied surfaces by means of this technique. Thus, anticorrosive layers and adhesion promoter layers can be applied to many metals without the use of solvents and hence in an environmentally friendly manner. Atmospheric-pressure plasma Atmospheric-pressure plasma (or AP plasma or normal pressure plasma) is a plasma in which the pressure approximately matches that of the surrounding atmosphere – the so-called normal pressure. Atmospheric-pressure plasmas have prominent technical significance because in contrast with low-pressure plasma or high-pressure plasma no reaction vessel is needed to ensure the maintenance of a pressure level differing from atmospheric pressure. Accordingly, depending on the