時(shí)間：2011-03-11 23:11來源：藍(lán)天飛行翻譯 作者：admin 點(diǎn)擊：次
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Celluloid. The registered trade name for one of the early thermoplastic materials. Celluloid is made from cellulose nitrate and camphor. cellulose. A material obtained from natural fibrous plants such as cotton and kapok. Cellulose is treated with certain acids to make the base for some plastic materials. cellulose acetate butyrate dope (aircraft finishing material). A form of finishing material for fabric-covered aircraft made of a cellulose fiber dissolved in a mixture of acetic and butyric acids. Plasticizers, solvents, and thinners are mixed with the film base to give it the proper working qualities. Cellulose acetate butyrate dope, also called CAB dope or, more simply, butyrate dope, has become more popular than the older cellulose nitrate dope because it is far less flammable than nitrate dope. cellulose nitrate. A compound made by treating cellulose with a mixture of nitric and sulfuric acids. Cellulose nitrate is used as the base for certain plastics, and as a component in the manufacture of explosives. Cellulose nitrate is also known as nitrocellulose and guncotton. cellulose nitrate dope (aircraft finishing material). A form of finishing material for fabric-covered aircraft made of a cellulose fiber dissolved in nitric and sulfuric acids. Plasticizers, solvents, and thinners are mixed with the film base to give it the proper working qualities. Cellulose nitrate dope (generally called nitrate dope) is an excellent adhesive, but it is being replaced to a great extent by butyrate dope. Butyrate dope is not as good an adhesive, but it is much less flammable. Celsius temperature. Temperature measured on a scale that sets the freezing point of water at 0° and its boiling point at 100°. There are 100 equal graduations called degrees between these two points. Absolute zero is –273°C. Celsius temperature was formerly called centigrade temperature. CEMF (counterelectromotive force). A voltage produced in the armature of an electric motor as the armature windings cut across the fixed magnetic field. The polarity of the CEMF is opposite the polarity of the voltage applied to the motor, and it opposes the applied voltage. center. A point within an object that is the same distance from all points on the surface of the object. center drill. A cutting tool which combines a twist drill and a 60° countersink. A center drill is used to drill the center hole in a piece of metal so it can be mounted between the centers in a lathe. centering cam (landing gear component). A cam on the shock strut of a retractable nose gear that aligns the wheel when there is no weight on the landing gear, so it will fit into the nose wheel well. centering cones (propeller component). Cones installed on a splined propeller shaft to hold the propeller hub centered. The rear cone is a single-piece split bronze cone, and the front cone is a two-piece chrome-plated steel cone. center line (aircraft drawings). A thin line consisting of alternate long and short dashes used in an aircraft drawing to show the center of a part. |
