时间:2011-03-11 23:11来源:蓝天飞行翻译 作者:admin 点击:次
biocidal action. The action of certain chemicals that kill bacteria. Biocidal agents are used in turbine engine fuel to kill the bacteria and microbes living in water that condenses inside aircraft fuel tanks. If these microscopic organisms are not killed, they will multiply and form a scum that holds water against the aircraft skin and promotes corrosion. Biocidal additives are also put in aircraft dope used on cotton or linen fabric to kill bacteria that can destroy either of these organic fabrics. biocidal agent. A chemical compound that is destructive to certain types of living organisms. biodegradable. A condition of a material that allows it to be broken down into simple products by the action of certain types of microorganisms. Paper and wood are normally biodegradable. If they are buried, they will, in time, change into simpler chemical compounds. Some man-made materials are not biodegradable, and they will not change. Disposing of large volumes of nonbiodegradable materials can be an environmental problem. biological warfare. Warfare using disease-producing microorganisms or toxic biological products to cause death or injury to humans, animals, or plants. biophysics. The branch of physics dealing with the application of physical laws to biological problems. biplane. An airplane having two main supporting aerodynamic surfaces (wings). The wings of a biplane are normally mounted so that one is approximately above the other. bipolar transistor. A solid-state component in which the flow of current between its emitter and collector is controlled by a much smaller flow of current into or out of its base. Bipolar transistors may be of either the NPN or PNP type. bipropellant rocket. A rocket using two separate propellants which are kept separate until they are mixed in the combustion chamber. |