difference detector
81Time-of-flight — The time of flight (TOF) describes the method used to measure the time that it takes for a particle, object or stream to reach a detector while traveling over a known distance. In time of flight mass spectrometry, ions are accelerated by an… …
82Mach-Zehnder interferometer — The Mach Zehnder interferometer (named after physicists Ludwig Mach (son of Ernst Mach) and Ludwig Zehnder) is a device used to determine the phase shift caused by a small sample which is placed in the path of one of two collimated beams (thus… …
83Frequency mixer — This article is about non linear mixing operating in the frequency domain. For other types of mixers, see electronic mixer. Frequency Mixer Symbol. In electronics a mixer or frequency mixer is a nonlinear electrical circuit that creates new… …
84Anthropology and Archaeology — ▪ 2009 Introduction Anthropology Among the key developments in 2008 in the field of physical anthropology was the discovery by a large interdisciplinary team of Spanish and American scientists in northern Spain of a partial mandible (lower… …
85X-ray crystallography — can locate every atom in a zeolite, an aluminosilicate with many important applications, such as water purification. X ray crystallography is a method of determining the arrangement of atoms within a crystal, in which a beam of X rays strikes a… …
86Crystal radio — Crystal set redirects here. For the Australian rock band, see The Crystal Set. A modern reproduction of an antique crystal set. It is tuned to different stations by moving the sliding contact (right) up and down the tuning coil (red). The device… …
87Ionization chamber — An ionization chamber is a device used for two major purposes: detecting particles in air (as in a smoke detector), and for detection or measurement of ionizing radiation. An ionization chamber is an instrument constructed to measure the number… …
88Optical resolution — This article is about optical resolution in optics. For the method of separating enantiomers in chemistry, see Chiral resolution. Optical resolution describes the ability of an imaging system to resolve detail in the object that is being imaged.… …
89Ridge detection — The ridges (or the ridge set) of a smooth function of two variables is a set of curves whose points are, loosely speaking, local maxima in at least one dimension. For a function of N variables, its ridges are a set of curves whose points are… …
90Glossary of rail terminology — Rail transport Operations Track Maintenance High speed Gauge Stations …
