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Magna Carta ... magnetohydrodynamic power generator

Magna Carta: the charter of English liberties granted by King John in 1215 under threat of civil war and reissued with alterations in 1216, 1217, and 1225. [13 Related Articles]
Magna Graecia: group of ancient Greek cities along the coast of southern Italy; the people of this region were known to the Greeks as Italiotai and to the Romans as Graeci. The ...
magnacycle: (from the article "cyclothem") ...megacyclothems with some distinctive features have been called a hypercyclothem. Rock units, measuring several kilometres in thickness and spanning entire geologic systems, have been referred to as magnacycles. These larger ...
magnamycin: (from the article "Woodward, Robert Burns") ...chemical puzzle. During the 1950s, Woodward collaborated with the pharmaceutical company Pfizer, Inc., on the structural analysis of a new series of antibiotics: terramycin, aureomycin, and magnamycin.
Magnani, Anna: Italian actress, best known for her forceful portrayals of earthy, working-class women. [1 Related Articles]
Magnasco, Alessandro: Italian painter of the late Baroque period distinguished for his landscapes and genre paintings.
Magnavox Corporation: (from the article "electronic game") ...of pinball games in this prototype, Bushnell and Alcorn installed it in a local bar, where it became an immediate success as a coin-operated game. After clearing a legal obstacle ...
Magne, Tour: (from the article "Nimes") ...the best preserved. Like the amphitheatre, the building has had varied uses (town hall, private house, stable, and church) through the ages. It now houses a collection of Roman sculptures. ...
Magnel, Gustave: (from the article "bridge") The first major bridge made of prestressed concrete in the United States, the Walnut Lane Bridge (1950) in Philadelphia, was designed by Gustave Magnel and features three simply supported girder ...
Magnentius: usurping Roman emperor from Jan. 18, 350, to Aug. 11, 353. His career forms one episode in the struggles for imperial power that occurred after the death of Constantine the ... [2 Related Articles]
Magnes, Judah Leon: rabbi, religious leader, prime founder and first president of the Hebrew University of Jerusalem, and a Zionist who came to favour a binational Arab-Jewish state.
Magnesia ad Maeandrum: ancient inland city of Ionia, situated on a small tributary of the Maeander (Buyukmenderes) River about 12 miles southeast of Ephesus. According to Strabo, it was founded by some Thessalian ...
Magnesia ad Sipylum: city in ancient Lydia, just south of the Hermus (Gediz) River. Though lying in a rich district near prehistoric regions associated with Niobe and Tantalus, and itself going back to ...
Magnesia, Battle of: (from the article "Antiochus III") ...negotiate on the basis of Rome's previous demands, but the Romans insisted that he first evacuate the region west of the Taurus Mountains. When Antiochus refused, he was decisively defeated ...
magnesioferrite: (from the article "magnesioferrite") the mineral magnesium iron oxide, a member of the magnetite (q.v.) series of spinels.magnetitemagnetite...metallic, moderately hard octahedrons and masses in ...
magnesioriebeckite: (from the article "magnesioriebeckite") magnesium-rich variety of the silicate mineral riebeckite (q.v.).riebeckiteriebeckite...in the amphibole family. It forms part of a solid-solution series tha
magnesite: the mineral magnesium carbonate (MgCO₃), a member of the calcite group of carbonate minerals that is a principal source of magnesium. The mineral has formed as an alteration product from ... [4 Related Articles]
magnesium: chemical element, one of the alkaline-earth metals of main Group IIa of the periodic table, the lightest structural metal. Known originally through compounds such as Epsom salts (the sulfate), magnesia ... [19 Related Articles]
magnesium carbonate: (from the article "playa") ...the centre. The crystallization of these salts can be compared with the evaporation of brine in a dish. The first precipitates from the evaporating brine are calcium carbonate (CaCO₃) and ...
magnesium chloride: (from the article "magnesium processing") ...moist magnesium sulfate, using mercury as a cathode. The first metallic magnesium, however, was produced in 1828 by the French scientist A.-A.-B. Bussy. His work involved the reduction of molten ...
magnesium cordierite: (from the article "cordierite") The natural mineral has little commercial use. When clear, cordierite is sometimes cut as a gem; the stones from the gem gravels of Sri Lanka have been called water sapphires. ...
magnesium deficiency: condition in which magnesium is insufficient or is not utilized properly. Magnesium is a mineral that is essential to a variety of cellular metabolic reactions and sometimes has the ability ...
magnesium germanate: (from the article "olivine") ...and garnetiferous peridotite that contain olivines as their most abundant minerals, it is important to establish their behaviour when subjected to high pressures. Study of the olivine-like compound magnesium germanate, ...
magnesium hydride: (from the article "hydride") ...H⁻. The saline hydrides are generally considered those of the alkali metals and the alkaline-earth metals (with the possible exception of beryllium hydride, BeH₂, and magnesium hydride, MgH₂). These metals ...
magnesium hydroxide: (from the article "magnesium processing") ...solutions. Partly dehydrated magnesium chloride can be obtained by the Dow process, in which seawater is mixed in a flocculator with lightly burned reactive dolomite. An insoluble magnesium hydroxide precipitates ...
magnesium oxide: (from the article "Table 1: Raw Materials Used in the Manufacture of Portland Cement") The earliest known alkaline earth was lime (Latin: calx), which is now known to be calcium oxide; it was used in ancient times in the composition of mortar. Magnesia (the ...
magnesium processing: preparation of the ore for use in various products. [1 Related Articles]
magnesium sulfate: (from the article "Epsom and Ewell") ...county of Surrey, England, at the foot of the North Downs, on the southwestern periphery of Greater London. It became important with the discovery (c. 1618) of mineral springs (from ...
magnesium tungstate: (from the article "fluorescent lamp") ...The inside of the tube is coated with phosphors, substances that absorb ultraviolet radiation and fluoresce (reradiate the energy as visible light). Two common phosphors are zinc silicate and magnesium ...
magnet: any material capable of attracting iron and producing a magnetic field outside itself. By the end of the 19th century all the known elements and many compounds had been tested ... [18 Related Articles]
Magnet Cove: (from the article "Arkansas") ...plants. Experimental use of lignite in coal-fired electrical generating stations offers the possibility of extensive commercial development of the widespread lignite deposits in southern Arkansas. Magnet Cove, near Hot Springs, ...
magnet ring: (from the article "particle accelerator") The progress in research made possible by raising the energies of protons led to the building of successively larger accelerators; the trend was ended only by the cost of fabricating ...
Magnetherm process: (from the article "magnesium processing") ...(aluminum oxide, Al₂O₃) to the charge, the melting point can be reduced to 1,550°-1,600° C (2,825°-2,900° F). This technique, utilized in the Magnetherm process, has the advantage that the liquid ...
magnetic anomaly: (from the article "paleogeography") Earth's magnetic field has another important property. Like the Sun's magnetic field, Earth's magnetic field periodically "flips," or reverses polarity-that is, the North and South poles switch places. Fluctuations, or ...
magnetic bottle: (from the article "magnetic mirror") ...along its original path. The exact location at which this mirroring occurs depends only upon the initial pitch angle describing its helical path. Two such magnetic mirrors can be arranged ...
magnetic bubble memory: (from the article "ferrite") ...cores of digital computers, since it enables a tiny ferrite ring to store binary bits of information. Another type of computer memory can be made of certain single-crystal ferrites in ...
magnetic ceramics: oxide materials that exhibit a certain type of permanent magnetization called ferrimagnetism. Commercially prepared magnetic ceramics are used in a variety of permanent magnet, transformer, telecommunications, and information recording applications. ...
magnetic charge: (from the article "magnetic monopole") hypothetical particle with a magnetic charge, a property analogous to an electric charge. As implied by its name, the magnetic monopole consists of a single pole, as opposed to the ...
magnetic circuit: closed path to which a magnetic field, represented as lines of magnetic flux, is confined. In contrast to an electric circuit through which electric charge flows, nothing actually flows in ... [1 Related Articles]
magnetic compass: (from the article "navigation") The magnetic compassdevelopment and usecompass The oldest and most familiar type of compass is the magnetic compass, which is used ...
magnetic confinement: (from the article "nuclear fusion") In magnetic confinement the particles and energy of a hot plasma are held in place using magnetic fields. A charged particle in a magnetic field experiences a Lorentz force that ...
magnetic damping: (from the article "damping") In magnetic damping, energy of motion is converted to heat by way of electric eddy currents induced in either a coil or an aluminum plate (attached to the oscillating object) ...
magnetic dipole: generally a tiny magnet of microscopic to subatomic dimensions, equivalent to a flow of electric charge around a loop. Electrons circulating around atomic nuclei, electrons spinning on their axes, and ... [6 Related Articles]
magnetic disk: (from the article "computer memory") Magnetic disks are coated with a magnetic material such as iron oxide. There are two types: hard disks made of rigid aluminum or glass, and removable diskettes made of flexible ...
magnetic drum: (from the article "magnetic recording") Such magnetic recording mediums as drums and ferrite cores have been used for data storage since the early 1950s. A more recent development is the magnetic bubble memory devised in ...
magnetic field: region in the neighbourhood of a magnet, electric current, or changing electric field, in which magnetic forces are observable. Magnetic fields such as that of the Earth cause magnetic compass ... [74 Related Articles]
magnetic field strength: (from the article "magnetism") The field H is called the magnetic intensity and, like M, is measured in units of amperes per metre. (It is sometimes also called ...
magnetic flux: (from the article "International System of Units (SI)") ...discovery in 1831 of the phenomenon of magnetic induction is one of the great milestones in the quest toward understanding and exploiting nature. Stated simply, Faraday found that (1) a ...
magnetic flux density: (from the article "International System of Units (SI)") ...H, caused by the current forces some or all of the atomic magnets in the material to align with the field. The net effect of this alignment is to increase ...
magnetic force: attraction or repulsion that arises between electrically charged particles because of their motion; the basic force responsible for the action of electric motors and the attraction of magnets for iron. ... [4 Related Articles]
magnetic glass: (from the article "amorphous solid") The last entry in the Table is an application of metallic glasses having magnetic properties. These are typically iron-rich amorphous solids with compositions such as Fe_0.8B_0.2 iron-boron and Fe_0.8B_0.1Si_0.1 iron-boron-silicon. ...
magnetic hyperfine structure: (from the article "spectroscopy") ...nucleus and the magnetic field produced by the surrounding electrons. This additional structure of an atom's levels or of spectral lines caused by the magnetic properties of its nucleus is ...
Magnetic Island: island in the Cumberland Islands, off the coast of northeastern Queensland, Australia, in Halifax Bay, an inlet of the Coral Sea. It is one of the most easily accessible islands ...
magnetic levitation: (from the article "railroad") From the 1970s, interest in an alternative high-speed technology centred on magnetic levitation, or maglev. This vehicle rides on an air cushion created by electromagnetic reaction between an on-board device ...
magnetic map: (from the article "magnetic survey") ...makes measurements at each station on the grid. The corrected data he records is then entered on a scale drawing of the grid, and contour lines are drawn between points ...
magnetic mine: (from the article "mine") ...mine's surface and activate the firing mechanism when the hull of a passing ship strikes them. Other types of detonators used on submarine mines include magnetic, pressure, and acoustic ones. ...
magnetic mirror: static magnetic field that, within a localized region, has a shape such that approaching charged particles are repelled back along their path of approach. [3 Related Articles]
magnetic moment: (from the article "Physical Sciences") ...physicists headaches was the muon. The generally accepted theory of fundamental particles, called the Standard Model, very precisely predicted the value of a property of these particles called the magnetic ...
magnetic monopole: hypothetical particle with a magnetic charge, a property analogous to an electric charge. As implied by its name, the magnetic monopole consists of a single pole, as opposed to the ...
magnetic observatory: (from the article "geomagnetic field") Magnetic observatories continuously measure and record the Earth's magnetic field at a number of locations. In an observatory of this sort, magnetized needles with reflecting mirrors are suspended by quartz ...
magnetic permeability: relative increase or decrease in the resultant magnetic field inside a material compared with the magnetizing field in which the given material is located; or the property of a material ... [5 Related Articles]
magnetic pigment: (from the article "surface coating") ...(ZnCrO₄) for corrosion control in primers, antimony oxide (Sb₂O₃) for fire-retardant coatings, and some compounds such as copper oxide (CuO) for barnacle control. Magnetic pigments, such as acicular iron oxide ...
magnetic pole: region at each end of a magnet where the external magnetic field is strongest. A bar magnet suspended in the Earth's magnetic field orients itself in a north-south direction. The ... [5 Related Articles]
magnetic prospecting: (from the article "rock") An understanding of rock magnetization is important in at least three different areas: prospecting, geology, and materials science. In magnetic prospecting, one is interested in mapping the depth, size, type, ...
magnetic pulsation: (from the article "geomagnetic field") ...in the magnetic field (hence their older name, micropulsations). These waves typically have amplitudes ranging from 100 to 0.1 nanoteslas, with lower frequencies exhibiting larger amplitudes. Magnetic pulsations have been ...
magnetic quantum number: (from the article "spectroscopy") There is a magnetic quantum number also associated with the angular momentum of the quantum state. For a given orbital momentum quantum number l, there are 2l + 1 integral ...
magnetic random access memory: (from the article "nanotechnology") Another approach to information storage that is dependent on designing nanometre-thick magnetic layers is under commercial development. Known as magnetic random access memory (MRAM), a line of electrically switchable magnetic ...
magnetic reconnection: (from the article "geomagnetic field") The observed dependence of geomagnetic activity on the orientation of the IMF is explained by most researchers as a consequence of magnetic reconnection. In reconnection, two oppositely directed magnetic fields ...
magnetic recording: method of preserving sounds, pictures, and data in the form of electrical signals through the selective magnetization of portions of a magnetic material. The principle of magnetic recording was first ... [11 Related Articles]
magnetic resonance: absorption or emission of electromagnetic radiation by electrons or atomic nuclei in response to the application of certain magnetic fields. The principles of magnetic resonance are applied in the laboratory ... [3 Related Articles]
magnetic resonance angiography: (from the article "diagnosis") Magnetic resonance angiography, a unique form of MRI technology, can be used to produce an image of flowing blood. This permits the visualization of arteries and veins without the need ...
magnetic resonance force microscopy: (from the article "Physical Sciences") ...a solid. Dan Rugar and co-workers at the IBM Almaden Research Center, San Jose, Calif., combined the techniques of magnetic resonance imaging and atomic force microscopy to create a technique ...
magnetic resonance imaging: three-dimensional diagnostic imaging technique used to visualize organs and structures inside the body without the need for X-rays or other radiation. Magnetic resonance imaging (MRI) is valuable for providing detailed ... [8 Related Articles]
magnetic resonance spectrometry: (from the article "heterocyclic compound") Magnetic resonance spectra are indispensable today for studies in heterocyclic chemistry. Proton resonance spectra, the most common type, yield information regarding the number of hydrogen atoms in the molecule, their ...
magnetic resonance spectroscopy: diagnostic imaging technique based on the detection of metabolites in tissues. Magnetic resonance spectroscopy (MRS) is related to magnetic resonance imaging (MRI) in that it uses the same machinery; however, ...
magnetic Reynolds number: combination of quantities that indicates the dynamic behaviour of a plasma. This number is analogous to the Reynolds number of ordinary fluid mechanics, which is used to determine whether or ...
magnetic saturation: (from the article "magnetism") ...temperature, corresponding to Curie's law. When the value of (mB/kT) is large enough to align nearly all the dipoles with the field, the magnetization approaches a saturation value.
magnetic sensor: (from the article "ignition system") ...circuit to the coils, turning them on and off. The reluctor ring is mounted on the crankshaft so that as the crankshaft rotates the magnetic sensor is triggered by notches ...
magnetic separation: (from the article "mineral processing") Magnetic separation is based on the differing degrees of attraction exerted on various minerals by magnetic fields. Success requires that the feed particles fall within a special size spectrum (0.1 ...
magnetic spin quantum number: (from the article "spectroscopy") ...angular momenta. The spin quantum number is s = 12, so in the presence of a magnetic field an electron can have one of two orientations corresponding to magnetic spin ...
magnetic storm: disturbance of the Earth's upper atmosphere brought on by solar flares-i.e., bright eruptions from the visible portion of the Sun's chromosphere. The material associated with these flares consists primarily of ... [4 Related Articles]
magnetic survey: one of the tools used by the exploration geophysicist in his search for mineral-bearing ore bodies or even oil-bearing sedimentary structures. The essential feature is the measurement of the magnetic-field ... [2 Related Articles]
magnetic susceptibility: quantitative measure of the extent to which a material may be magnetized in relation to a given applied magnetic field. The magnetic susceptibility of a material, commonly symbolized by chi_m, ... [4 Related Articles]
magnetic tape: (from the article "magnetic recording") Magnetic tape devices. Magnetic tape provides a compact, economical means of preserving and reproducing varied forms of information. Recordings on tape can be played back immediately and are easily erased, ...
magnetic thermometer: (from the article "thermometer") Other thermometers operate by sensing sound waves or magnetic conditions associated with temperature changes. Magnetic thermometers increase in efficiency as temperature decreases, which makes them extremely useful in measuring very ...
magnetic variable star: (from the article "star") Spectrum and magnetic variables, mostly of spectral type A, show only small amplitudes of light variation but often pronounced spectroscopic changes. Their spectra typically show strong lines of metals such ...
magnetic videodisc: (from the article "videodisc") The magnetic videodisc has an oxide-coated surface onto which input signals are recorded as magnetic patterns in spiral tracks. The video heads of the playback unit pick up these impressions ...
magnetic-core storage: any of a class of computer memory devices consisting of a large array of tiny toruses of a hard magnetic material that can be magnetized in either of two directions ... [3 Related Articles]
magnetic-polarity time scale: (from the article "Earth, geologic history of") ...lavas were extruded from the mid-oceanic ridges, they were alternately magnetized parallel and opposite to the present magnetic field of the Earth and are thus referred to as normal and ...
magnetism: phenomenon associated with the motion of electric charges. This motion can take many forms. It can be an electric current in a conductor or charged particles moving through space, or ... [29 Related Articles]
magnetite: iron oxide mineral (FeFe₂O₄, or Fe₃O₄) that is the chief member of one of the series of the spinel (q.v.) group. Minerals in this series form black to brownish, metallic, ... [15 Related Articles]
magnetite series: (from the article "spinel") ...group is divided into three immiscible series: the spinel (aluminum-spinel) series, in which B is aluminum; the chromite (chromium-spinel) series, in which B is chromium; and the magnetite (iron-spinel) series, ...
magnetization: (from the article "magnetism") ...field, matter is either attracted or repelled in the direction of the gradient of the field. This property is described by the magnetic susceptibility of the matter and depends on ...
magnetization electron: (from the article "magnetism") ...are thought to be the result of the magnetic moment associated with the spin of an electron in an outer atomic shell-specifically, the third d shell. Such electrons are referred ...
magneto: permanent-magnet generator mainly employed for ignition of compressed gasses in internal combustion engines. Primary applications have been in small aircraft, marine, tractor, and motorcycle engines, which may not have an ... [2 Related Articles]
magneto-optical disk: (from the article "computer memory") Magneto-optical discs are a hybrid storage medium. In reading, spots with different directions of magnetization give different polarization in the reflected light of a low-power laser beam. In writing, every ...
magneto-optical shutter: (from the article "photography, technology of") The shortest exposure with mechanical shutters is about 14,000 second. Special high-speed shutter systems are magneto-optical, electro-optical, or electronic. A magneto-optical shutter (Faraday shutter) consists of a glass cylinder placed ...
magnetoencephalography: imaging technique that measures the weak magnetic fields emitted by neurons. An array of cylinder-shaped sensors monitors the magnetic field pattern near the patient's head to determine the position and ... [1 Related Articles]
magnetogram: (from the article "geomagnetic field") ...Typical scale factors for such observatories correspond to 2-10 nanoteslas per millimetre vertically and 20 millimetres per hour horizontally. A print of the developed negative is called a magnetogram.
magnetohydrodynamic instability: (from the article "plasma") ...each type of configuration. Various types of instabilities can occur in plasma. These lead to a loss of plasma and a catastrophic decrease in containment time. The most important of ...
magnetohydrodynamic power generator: any of a class of devices that generate electric power by means of the interaction of a moving fluid (usually an ionized gas or plasma) and a magnetic field. Magnetohydrodynamic ... [4 Related Articles]