时间：2011-03-11 23:13来源：蓝天飞行翻译 作者：admin 点击：次
|
ionize. The process of making positive ions by freeing electrons from balanced atoms or molecules. The electrons freed from the atoms travel to other atoms or molecules and become part of them. ionosphere. A region of electrically charged particles (ions) extending upward from about 30 miles above the surface of the earth. The ionosphere is composed of a number of layers that vary in the amount of ionization, with the lower layers not ionized as heavily as the higher layers. The names of the layers of the ionosphere, beginning at the lower layer, are: D region E region (the Kennelly Heaviside layer) F1 region F2 region Heliosphere Protonosphere Magnetosphere IRAN (aircraft inspection). A type of aircraft inspection in which the aircraft is inspected and any needed repairs are made. IRAN stands for “inspect and repair as necessary.” IRBM (intermediate-range ballistic missile). A ballistic missile with a range of between 200 and 1,500 miles. See ballistic missile. IR drop. The decrease in electrical pressure caused by electrons flowing through a resistance. The amount of IR drop, expressed in volts, is found by multiplying the current (I), in amps, by the resistance (R), in ohms. iridium. A very hard, brittle, highly corrosion-resistant, whitish-yellow, metallic chemical element. Iridium’s symbol is Ir, its atomic number is 77, and its atomic weight is 192.2. Iridium is used for electrical contacts and as an alloying agent in high-temperature metals. Spark plugs having fine-wire electrodes made of iridium are used in engines in which lead-fouling is a problem. Irish linen (aircraft fabric). A strong organic fabric made from the fibers of the flax plant. Irish linen is approved as a direct replacement for grade-A cotton fabric as a covering material for aircraft structures. iron. A silvery-white, lustrous, malleable, ductile, metallic chemical element. Iron’s symbol is Fe, its atomic number is 26, and its atomic weight is 55.847. Iron is an important structural metal in the form of steel (iron with controlled amounts of carbon and other elements). iron carbide. The form in which carbon exists in steel. The amount of iron carbide and its distribution in the metal determine the hardness of the steel. iron-constantan thermocouple. A thermocouple combination used to measure temperatures up to about 410°C. Iron forms the positive element, and constantan, the negative. Iron-constantan thermocouples are generally used to measure cylinder head temperature on reciprocating engines. iron-core coil. A type of inductor wound around a core of laminated iron sections. Iron has a much higher permeability than air, and an iron-core coil has a greater inductance than an equivalent size air-core coil. iron-core transformer (electrical component). A transformer with the coils wound over a core of laminated soft iron. The soft iron core concentrates the lines of magnetic flux and increases the inductance of the coil. The laminations decrease the eddy current losses in the core. |
