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Quadrupole Mass Spectrometer
In mass spectrometry, the quadrupole mass analyzer (or quadrupole mass filter) is a type of mass analyzer originally conceived by Nobel laureate Wolfgang Paul and his student Helmut Steinwedel. As the name implies, it consists of four cylindrical rods, set parallel to each other. In a quadrupole mass spectrometer (QMS) the quadrupole is the ''mass analyzer'' – the component of the instrument responsible for selecting sample ions based on their mass-to-charge ratio (''m/z''). Ions are separated in a quadrupole based on the stability of their trajectories in the oscillating electric fields that are applied to the rods. Principle of operation The quadrupole consists of four parallel metal rods. Each opposing rod pair is connected together electrically, and a radio frequency (RF) voltage with a DC offset voltage is applied between one pair of rods and the other. Ions travel down the quadrupole between the rods. Only ions of a certain mass-to-charge ratio will reach the detector fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mass Spectrometer Quadrupole
Mass is an Intrinsic and extrinsic properties, intrinsic property of a physical body, body. It was traditionally believed to be related to the physical quantity, quantity of matter in a body, until the discovery of the atom and particle physics. It was found that different atoms and different elementary particle, elementary particles, theoretically with the same amount of matter, have nonetheless different masses. Mass in modern physics has multiple Mass in special relativity, definitions which are conceptually distinct, but physically equivalent. Mass can be experimentally defined as a measure (mathematics), measure of the body's inertia, meaning the resistance to acceleration (change of velocity) when a net force is applied. The object's mass also determines the Force, strength of its gravitational attraction to other bodies. The SI base unit of mass is the kilogram (kg). In physics, mass is Mass versus weight, not the same as weight, even though mass is often determined by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triple Quadrupole Mass Spectrometer
A triple quadrupole mass spectrometer (TQMS), is a tandem mass spectrometry, tandem mass spectrometer consisting of two quadrupole mass analyzers in series, with a (non-mass-resolving) Radio-frequency quadrupole, radio frequency (RF)–only quadrupole between them to act as a cell for collision-induced dissociation. This configuration is often abbreviated QqQ, here Q1q2Q3. History The arrangement of three quadrupoles was first developed by J.D. Morrison of La Trobe University, Australia for the purpose of studying the photodissociation of gas-phase ions. After coming into contact with Prof. Christie G. Enke and his then graduate student Richard Yost, Morrison's linear arrangement of the three quadrupoles probed the construction of the first triple-quadrupole mass spectrometer. In the years following, the first commercial triple-quadrupole mass spectrometer was developed at Michigan State University by Christie G. Enke, Enke and Yost in the late 1970s. It was later found that the t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gas Chromatography-mass Spectrometry
Gas is a state of matter that has neither a fixed volume nor a fixed shape and is a compressible fluid. A ''pure gas'' is made up of individual atoms (e.g. a noble gas like neon) or molecules of either a single type of atom ( elements such as oxygen) or from different atoms ( compounds such as carbon dioxide). A ''gas mixture'', such as air, contains a variety of pure gases. What distinguishes gases from liquids and solids is the vast separation of the individual gas particles. This separation can make some gases invisible to the human observer. The gaseous state of matter occurs between the liquid and plasma states, the latter of which provides the upper-temperature boundary for gases. Bounding the lower end of the temperature scale lie degenerative quantum gases which are gaining increasing attention. High-density atomic gases super-cooled to very low temperatures are classified by their statistical behavior as either Bose gases or Fermi gases. For a comprehensive listing of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liquid Chromatography-mass Spectrometry
Liquid is a state of matter with a definite volume but no fixed shape. Liquids adapt to the shape of their container and are nearly incompressible, maintaining their volume even under pressure. The density of a liquid is usually close to that of a solid, and much higher than that of a gas. Therefore, liquid and solid are classified as condensed matter. Meanwhile, since both liquids and gases can flow, they are categorized as fluids. A liquid is composed of atoms or molecules held together by intermolecular bonds of intermediate strength. These forces allow the particles to move around one another while remaining closely packed. In contrast, solids have particles that are tightly bound by strong intermolecular forces, limiting their movement to small vibrations in fixed positions. Gases, on the other hand, consist of widely spaced, freely moving particles with only weak intermolecular forces. As temperature increases, the molecules in a liquid vibrate more intensely, causing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quadrupole Time-of-flight Mass Spectrometer
A hybrid mass spectrometer is a device for tandem mass spectrometry that consists of a combination of two or more '' m/z'' separation devices of different types. Notation The different ''m/z'' separation elements of a hybrid mass spectrometer can be represented by a shorthand notation. The symbol ''Q'' represents a quadrupole mass analyzer, ''q'' is a radio frequency collision quadrupole, ''TOF'' is a time-of-flight mass spectrometer, ''B'' is a magnetic sector and ''E'' is an electric sector. Sector quadrupole A sector instrument can be combined with a collision quadrupole and quadrupole mass analyzer to form a hybrid instrument. A BEqQ configuration with a magnetic sector (B), electric sector (E), collision quadrupole (q) and ''m/z'' selection quadrupole (Q) have been constructed and an instrument with two electric sectors (BEEQ) has been described. Quadrupole time-of-flight A triple quadrupole mass spectrometer with the final quadrupole replaced by a time-of-flight device is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Time-of-flight
Time of flight (ToF) is the measurement of the time taken by an object, particle or wave (be it acoustic, electromagnetic, etc.) to travel a distance through a medium. This information can then be used to measure velocity or path length, or as a way to learn about the particle or medium's properties (such as composition or flow rate). The traveling object may be detected directly (direct time of flight, dToF, e.g., via an ion detector in mass spectrometry) or indirectly (indirect time of flight, iToF, e.g., by light scattered from an object in laser doppler velocimetry). Time of flight technology has found valuable applications in the monitoring and characterization of material and biomaterials, hydrogels included. Overview In electronics, one of the earliest devices using the principle are ultrasonic distance-measuring devices, which emit an ultrasonic pulse and are able to measure the distance to a solid object based on the time taken for the wave to bounce back to the emitter. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sector Instrument
A sector instrument is a general term for a class of mass spectrometer that uses a static electric (E) or magnetic (B) sector or some combination of the two (separately in space) as a mass analyzer. Popular combinations of these sectors have been the EB, BE (of so-called reverse geometry), three-sector BEB and four-sector EBEB (electric-magnetic-electric-magnetic) instruments. Most modern sector instruments are double-focusing instruments (first developed by Francis William Aston, Arthur Jeffrey Dempster, Kenneth Bainbridge and Josef Mattauch in 1936) in that they focus the ion beams both in direction and velocity. Theory The behavior of ions in a homogeneous, linear, static electric or magnetic field (separately) as is found in a sector instrument is simple. The physics are described by a single equation called the Lorentz force law. This equation is the fundamental equation of all mass spectrometric techniques and applies in non-linear, non-homogeneous cases too and is an impo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hybrid Mass Spectrometer
A hybrid mass spectrometer is a device for tandem mass spectrometry that consists of a combination of two or more '' m/z'' separation devices of different types. Notation The different ''m/z'' separation elements of a hybrid mass spectrometer can be represented by a shorthand notation. The symbol ''Q'' represents a quadrupole mass analyzer, ''q'' is a radio frequency collision quadrupole, ''TOF'' is a time-of-flight mass spectrometer, ''B'' is a magnetic sector and ''E'' is an electric sector. Sector quadrupole A sector instrument can be combined with a collision quadrupole and quadrupole mass analyzer to form a hybrid instrument. A BEqQ configuration with a magnetic sector (B), electric sector (E), collision quadrupole (q) and ''m/z'' selection quadrupole (Q) have been constructed and an instrument with two electric sectors (BEEQ) has been described. Quadrupole time-of-flight A triple quadrupole mass spectrometer A triple quadrupole mass spectrometer (TQMS), is a ta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Richard Yost
Richard A Yost (born 31 May 1953 in Martins Ferry) is an American scientist and University Professor Emeritus at the University of Florida. He is best known for his work inventing the triple quadrupole mass spectrometer.The Encyclopedia of Mass Spectrometry: Volume 9: Historical Perspectives, Part B: Notable People in Mass Spectrometry Yost received his BS degree in chemistry in 1974 from the University of Arizona, having performed undergraduate research in chromatography with Mike Burke and his PhD degree in Analytical Chemistry in 1979 from Michigan State University, having performed graduate research with Chris Enke. He joined the faculty of the University of Florida after his graduate research. He served as director of the Southeast Center for Integrated Metabolomics (SECIM) and of NIH's Metabolomics Consortium Coordinating Center (M3C). He is also a Professor of Pathology at both the University of Florida and the University of Utah/ ARUP. His professional activities ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Christie G
Christie can refer to: People * Christie (given name) * Christie (surname) * Clan Christie Other uses * Christie's, the auction house * Christie, the Canadian division of Nabisco * Christie (TTC), subway station in Toronto, Ontario, Canada * Christie (audiovisual company), a digital projection company * Christie (automobile company), existed from 1904 to 1910 * Christie (band), UK rock band * The Christie, a cancer hospital in Manchester, England * Christie Hotel, a historic building in Hollywood, California * Christie Realty Building, a historic former hotel in Hollywood, California * Christie suspension, vehicle (tank) suspension system invented by U.S. engineer Walter Christie * Christie Organ, a brand of theatre pipe organ * Christie (Dead or Alive), a video game character in ''Dead or Alive'' series See also * Christy (other) Christy may refer to: People * Christy (given name) * Christy (surname) * Christy (musician), Christy O'Donnell (born 1997), Scotti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photodissociation
Photodissociation, photolysis, photodecomposition, or photofragmentation is a chemical reaction in which molecules of a chemical compound are broken down by absorption of light or photons. It is defined as the interaction of one or more photons with one target molecule that dissociates into two fragments. Here, “light” is broadly defined as radiation spanning the vacuum ultraviolet (VUV), ultraviolet (UV), visible, and infrared (IR) regions of the electromagnetic spectrum. To break covalent bonds, photon energies corresponding to visible, UV, or VUV light are typically required, whereas IR photons may be sufficiently energetic to detach ligands from coordination complexes or to fragment supramolecular complexes. Photolysis in photosynthesis Photolysis is part of the light-dependent reaction, light phase, photochemical phase, or Hill reaction of photosynthesis. The general reaction of photosynthetic photolysis can be given in terms of photons as: :\ce + 2 \text \longrigh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
La Trobe University
La Trobe University is a public university, public research university based in Melbourne, Victoria (Australia), Victoria, Australia. Its main campus is located in the suburb of Bundoora, Victoria, Bundoora. The university was established in 1964, becoming the third university in the state of Victoria and the twelfth university in Australia. La Trobe is one of the Australian verdant universities and also part of the Innovative Research Universities group. La Trobe's original and principal campus is located in the Melbourne metropolitan area, within the northern Melbourne suburb of Bundoora. It is the largest metropolitan campus in the country, occupying over . It has two other major campuses located in the regional Victorian city of Bendigo and the twin border cities of Albury-Wodonga. There are two smaller regional campuses in Mildura and Shepparton and a city campus in Melbourne's Central business district, CBD on Collins Street, Melbourne, Collins Street and in Sydney on Eli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
