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dispersion
dispersion
1. The spreading of a body of water as it flows. Lateral dispersion is the widening of the path taken by ground-water as it flows from a known point of origin through a rock matrix, due to its movement around individual mineral grains within the main rock body. Unless it flows in well-defined fissures or fractures, water does not travel through a rock in a straight line but is forced to flow across a widening front because of the granular nature of the rock matrix. Longitudinal dispersion is the spreading out of a body of water along its own flow path, due to the differences in water velocities in larger and smaller pores of the rock. Both modes of dispersion are normally observed by means of tracers. Lateral and longitudinal dispersion also occur in river channels, where they are due to differences in flow velocity across the channel and between the water surface and the bed, and also to random fluctuations in velocity caused by turbulent eddies. 2. The process of separating soil particles (as in aggregates) from each other so that they may react as individual particles. Aggregates or peds of soil particles are destroyed by dispersion (and their formation is initiated by flocculation. 3. The distortion of a wave train that occurs when velocity varies with frequency and consequently the phase velocity is not the same as the group velocity. There is minimal dispersion for most body waves (although electromagnetic body waves are subject to considerable dispersion) but it is important for surface waves, especially Love waves, particularly in the presence of velocity-layering near the surface. 4. In mineral optics, a measure of the difference in refractive index, determined by direct observation of the biaxial interference figure using the two extreme wavelengths of the visible spectrum (red and violet). Both isogyres are observed for red and violet tints. 5. See SWELL. |
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AILSA ALLABY and MICHAEL ALLABY. "dispersion." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. 13 Feb. 2012 <http://www.encyclopedia.com>. AILSA ALLABY and MICHAEL ALLABY. "dispersion." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. (February 13, 2012). http://www.encyclopedia.com/doc/1O13-dispersion.html AILSA ALLABY and MICHAEL ALLABY. "dispersion." A Dictionary of Earth Sciences. 1999. Retrieved February 13, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O13-dispersion.html |
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dispersion
dispersion
1. In statistics, the internal pattern of a population (i.e. its distribution about the mean value). In spatial statistics, the pattern relative to some specific location, or of individuals relative to one another (e.g. clumped or random). 2. In pedology, the process of separating soil particles (as in aggregates) from each other so that they may react as individual particles. Aggregates or peds of soil particles are destroyed by dispersion (and formation is initiated by flocculation). 3. The spreading of a body of water as it flows. Lateral dispersion is the widening of the path taken by groundwater as it flows from a known point of origin through a rock matrix, owing to its movement around individual mineral grains within the main rock body. Unless it flows in well-defined fissures or fractures, water does not travel through a rock in a straight line but is forced to flow across a widening front because of the granular nature of the rock matrix. Longitudinal dispersion is the spreading out of a body of water along its own flow path, due to the differences in water velocities in larger and smaller pores of the rock. Both modes of dispersion are normally observed by means of tracers. Lateral and longitudinal dispersion also occur in river channels, where they are caused by differences in flow velocity across the channel and between the water surface and the bed, and also by random fluctuations in velocity caused by turbulent eddies. 4. See swell. |
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MICHAEL ALLABY. "dispersion." A Dictionary of Ecology. 2004. Encyclopedia.com. 13 Feb. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "dispersion." A Dictionary of Ecology. 2004. Encyclopedia.com. (February 13, 2012). http://www.encyclopedia.com/doc/1O14-dispersion.html MICHAEL ALLABY. "dispersion." A Dictionary of Ecology. 2004. Retrieved February 13, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O14-dispersion.html |
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dispersion
dispersion
1. The splitting of light into its constituent colours by a prism or diffraction grating. High dispersion means that the spectrum of an object is spread out more than in low dispersion, and thus more details can be seen; the degree of dispersion thus governs spectral resolution. A high-resolution spectrograph will produce a typical dispersion of 1–2 nm/mm. 2. A phenomenon in which electromagnetic waves of different frequencies travel at different speeds in certain media, such as ionized gases (plasmas). Interstellar matter is largely ionized hydrogen and is therefore dispersive. The time delay of a wave introduced by dispersion depends on the electron density along the line of sight, and is inversely proportional to the square of the observing frequency. Dispersion smears out rapid fluctuations in the source, a matter of great importance in the observation of pulsars. See also Dedispersion. |
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"dispersion." A Dictionary of Astronomy. 1997. Encyclopedia.com. 13 Feb. 2012 <http://www.encyclopedia.com>. "dispersion." A Dictionary of Astronomy. 1997. Encyclopedia.com. (February 13, 2012). http://www.encyclopedia.com/doc/1O80-dispersion.html "dispersion." A Dictionary of Astronomy. 1997. Retrieved February 13, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O80-dispersion.html |
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dispersion
dispersion n.
1. a scattered pattern of hits around the mean point of impact of bombs and projectiles dropped or fired under identical conditions. 2. in antiaircraft gunnery, the scattering of shots in range and deflection about the mean point of explosion. 3. the spreading or separating of troops, materiel, establishment, or activities which are usually concentrated in limited areas to reduce vulnerability. 4. in chemical and biological operations, the dissemination of agents in liquid or aerosol form. 5. in airdrop operations, the scatter of personnel and/or cargo in the drop zone. 6. in naval control of shipping, the reberthing of a ship in the periphery of the port area or in the vicinity of the port for its own protection in order to minimize the risk of damage from attack. |
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"dispersion." The Oxford Essential Dictionary of the U.S. Military. 2001. Encyclopedia.com. 13 Feb. 2012 <http://www.encyclopedia.com>. "dispersion." The Oxford Essential Dictionary of the U.S. Military. 2001. Encyclopedia.com. (February 13, 2012). http://www.encyclopedia.com/doc/1O63-dispersion.html "dispersion." The Oxford Essential Dictionary of the U.S. Military. 2001. Retrieved February 13, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O63-dispersion.html |
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dispersion
dispersion in chemistry, mixture in which fine particles of one substance are scattered throughout another substance. A dispersion is classed as a suspension , colloid , or solution . Generally, the particles in a solution are of molecular or ionic size; those in a colloid are larger but too small to be observed with an ordinary microscope; those in a suspension can be observed under a microscope or with the naked eye. A coarse mixture (e.g., sand mixed with sugar) is usually not thought of as a dispersion. |
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"dispersion." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. 13 Feb. 2012 <http://www.encyclopedia.com>. "dispersion." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. (February 13, 2012). http://www.encyclopedia.com/doc/1E1-dispers-che.html "dispersion." The Columbia Encyclopedia, 6th ed.. 2008. Retrieved February 13, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-dispers-che.html |
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dispersion
dispersion
1. In statistics, the internal pattern of a population, i.e. its distribution about the mean value. In spatial statistics, the pattern relative to some specific location, or of individuals relative to one another, e.g. clumped or random. 2. In pedology, the process of separating soil particles (as in aggregates) from each other so that they may react as individual particles. Aggregates or peds of soil particles are destroyed by dispersion (and formation is initiated by flocculation). |
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MICHAEL ALLABY. "dispersion." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. 13 Feb. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "dispersion." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. (February 13, 2012). http://www.encyclopedia.com/doc/1O7-dispersion.html MICHAEL ALLABY. "dispersion." A Dictionary of Plant Sciences. 1998. Retrieved February 13, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O7-dispersion.html |
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dispersion
dispersion What happens to light pulses as they are sent down a fibre optic transmission line. As they progress they expand and become more narrowly focused, the degree of dispersion depending on the wavelength. This is a major problem and much research is being carried out to reduce this effect. See SOLITON.
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DARREL INCE. "dispersion." A Dictionary of the Internet. 2001. Encyclopedia.com. 13 Feb. 2012 <http://www.encyclopedia.com>. DARREL INCE. "dispersion." A Dictionary of the Internet. 2001. Encyclopedia.com. (February 13, 2012). http://www.encyclopedia.com/doc/1O12-dispersion.html DARREL INCE. "dispersion." A Dictionary of the Internet. 2001. Retrieved February 13, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O12-dispersion.html |
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dispersion
dispersion In statistics, the internal pattern of a population, i.e. its distribution about the mean value. In spatial statistics, the pattern relative to some specific location, or of individuals relative to one another, e.g. clumped or random.
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MICHAEL ALLABY. "dispersion." A Dictionary of Zoology. 1999. Encyclopedia.com. 13 Feb. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "dispersion." A Dictionary of Zoology. 1999. Encyclopedia.com. (February 13, 2012). http://www.encyclopedia.com/doc/1O8-dispersion.html MICHAEL ALLABY. "dispersion." A Dictionary of Zoology. 1999. Retrieved February 13, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O8-dispersion.html |
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dispersion
dispersion see diffusion and dispersion in groundwater flow
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PAUL HANCOCK and BRIAN J. SKINNER. "dispersion." The Oxford Companion to the Earth. 2000. Encyclopedia.com. 13 Feb. 2012 <http://www.encyclopedia.com>. PAUL HANCOCK and BRIAN J. SKINNER. "dispersion." The Oxford Companion to the Earth. 2000. Encyclopedia.com. (February 13, 2012). http://www.encyclopedia.com/doc/1O112-dispersion.html PAUL HANCOCK and BRIAN J. SKINNER. "dispersion." The Oxford Companion to the Earth. 2000. Retrieved February 13, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O112-dispersion.html |
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dispersion
dispersion The English translation of diaspora.
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W. R. F. BROWNING. "dispersion." A Dictionary of the Bible. 1997. Encyclopedia.com. 13 Feb. 2012 <http://www.encyclopedia.com>. W. R. F. BROWNING. "dispersion." A Dictionary of the Bible. 1997. Encyclopedia.com. (February 13, 2012). http://www.encyclopedia.com/doc/1O94-dispersion.html W. R. F. BROWNING. "dispersion." A Dictionary of the Bible. 1997. Retrieved February 13, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O94-dispersion.html |
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dispersion
dispersion in physics: see spectrum . |
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Cite this article
"dispersion." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. 13 Feb. 2012 <http://www.encyclopedia.com>. "dispersion." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. (February 13, 2012). http://www.encyclopedia.com/doc/1E1-X-dispers-phy.html "dispersion." The Columbia Encyclopedia, 6th ed.. 2008. Retrieved February 13, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-X-dispers-phy.html |
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dispersion
dispersion See measures of variation.
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JOHN DAINTITH. "dispersion." A Dictionary of Computing. 2004. Encyclopedia.com. 13 Feb. 2012 <http://www.encyclopedia.com>. JOHN DAINTITH. "dispersion." A Dictionary of Computing. 2004. Encyclopedia.com. (February 13, 2012). http://www.encyclopedia.com/doc/1O11-dispersion.html JOHN DAINTITH. "dispersion." A Dictionary of Computing. 2004. Retrieved February 13, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O11-dispersion.html |
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dispersion
dispersion
•ashen, fashion, passion, ration
•abstraction, action, attraction, benefaction, compaction, contraction, counteraction, diffraction, enaction, exaction, extraction, faction, fraction, interaction, liquefaction, malefaction, petrifaction, proaction, protraction, putrefaction, redaction, retroaction, satisfaction, stupefaction, subtraction, traction, transaction, tumefaction, vitrifaction
•expansion, mansion, scansion, stanchion
•sanction
•caption, contraption
•harshen, Martian
•cession, discretion, freshen, session
•abjection, affection, circumspection, collection, complexion, confection, connection, convection, correction, defection, deflection, dejection, detection, direction, ejection, election, erection, genuflection, imperfection, infection, inflection, injection, inspection, insurrection, interconnection, interjection, intersection, introspection, lection, misdirection, objection, perfection, predilection, projection, protection, refection, reflection, rejection, resurrection, retrospection, section, selection, subjection, transection, vivisection
•exemption, pre-emption, redemption
•abstention, apprehension, ascension, attention, circumvention, comprehension, condescension, contention, contravention, convention, declension, detention, dimension, dissension, extension, gentian, hypertension, hypotension, intention, intervention, invention, mention, misapprehension, obtention, pension, prehension, prevention, recension, retention, subvention, supervention, suspension, tension
•conception, contraception, deception, exception, inception, interception, misconception, perception, reception
•Übermenschen • subsection
•ablation, aeration, agnation, Alsatian, Amerasian, Asian, aviation, cetacean, citation, conation, creation, Croatian, crustacean, curation, Dalmatian, delation, dilation, donation, duration, elation, fixation, Galatian, gyration, Haitian, halation, Horatian, ideation, illation, lavation, legation, libation, location, lunation, mutation, natation, nation, negation, notation, nutation, oblation, oration, ovation, potation, relation, rogation, rotation, Sarmatian, sedation, Serbo-Croatian, station, taxation, Thracian, vacation, vexation, vocation, zonation
•accretion, Capetian, completion, concretion, deletion, depletion, Diocletian, excretion, Grecian, Helvetian, repletion, Rhodesian, secretion, suppletion, Tahitian, venetian
•academician, addition, aesthetician (US esthetician), ambition, audition, beautician, clinician, coition, cosmetician, diagnostician, dialectician, dietitian, Domitian, edition, electrician, emission, fission, fruition, Hermitian, ignition, linguistician, logician, magician, mathematician, Mauritian, mechanician, metaphysician, mission, monition, mortician, munition, musician, obstetrician, omission, optician, paediatrician (US pediatrician), patrician, petition, Phoenician, physician, politician, position, rhetorician, sedition, statistician, suspicion, tactician, technician, theoretician, Titian, tuition, volition
•addiction, affliction, benediction, constriction, conviction, crucifixion, depiction, dereliction, diction, eviction, fiction, friction, infliction, interdiction, jurisdiction, malediction, restriction, transfixion, valediction
•distinction, extinction, intinction
•ascription, circumscription, conscription, decryption, description, Egyptian, encryption, inscription, misdescription, prescription, subscription, superscription, transcription
•proscription
•concoction, decoction
•adoption, option
•abortion, apportion, caution, contortion, distortion, extortion, portion, proportion, retortion, torsion
•auction
•absorption, sorption
•commotion, devotion, emotion, groschen, Laotian, locomotion, lotion, motion, notion, Nova Scotian, ocean, potion, promotion
•ablution, absolution, allocution, attribution, circumlocution, circumvolution, Confucian, constitution, contribution, convolution, counter-revolution, destitution, dilution, diminution, distribution, electrocution, elocution, evolution, execution, institution, interlocution, irresolution, Lilliputian, locution, perlocution, persecution, pollution, prosecution, prostitution, restitution, retribution, Rosicrucian, solution, substitution, volution
•cushion • resumption • München
•pincushion
•Belorussian, Prussian, Russian
•abduction, conduction, construction, deduction, destruction, eduction, effluxion, induction, instruction, introduction, misconstruction, obstruction, production, reduction, ruction, seduction, suction, underproduction
•avulsion, compulsion, convulsion, emulsion, expulsion, impulsion, propulsion, repulsion, revulsion
•assumption, consumption, gumption, presumption
•luncheon, scuncheon, truncheon
•compunction, conjunction, dysfunction, expunction, function, junction, malfunction, multifunction, unction
•abruption, corruption, disruption, eruption, interruption
•T-junction • liposuction
•animadversion, aspersion, assertion, aversion, Cistercian, coercion, conversion, desertion, disconcertion, dispersion, diversion, emersion, excursion, exertion, extroversion, immersion, incursion, insertion, interspersion, introversion, Persian, perversion, submersion, subversion, tertian, version
•excerption
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"dispersion." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. 13 Feb. 2012 <http://www.encyclopedia.com>. "dispersion." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. (February 13, 2012). http://www.encyclopedia.com/doc/1O233-dispersion.html "dispersion." Oxford Dictionary of Rhymes. 2007. Retrieved February 13, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O233-dispersion.html |
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