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quark
quark A fundamental particle, of which hadrons are believed to be composed. Quarks have charges that are either +⅔ or −⅓ of the electron's charge, and combine to make elementary particles. Baryons consist of three quarks, and mesons of two. For example, a proton consists of quarks with charges +⅔+⅔−⅓= 1 and a neutron consists of three with charges +⅔−⅔−⅓ = 0. Eighteen different quarks with various properties are thought to exist, with a corresponding number of antiquarks. An isolated quark has never been observed; quarks appear to exist only in combination as baryons or mesons.
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"quark." A Dictionary of Astronomy. 1997. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. "quark." A Dictionary of Astronomy. 1997. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O80-quark.html "quark." A Dictionary of Astronomy. 1997. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O80-quark.html |
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quark
quark Any one of six particles (although there is increasing evidence of another two) and their antiparticles (antiquarks) that are the constituents of the hadron group of elementary particles. They occur in one of six ‘flavours’: up, down, top, bottom, charmed, and strange. Antiquarks have similar flavours but their charge is opposite that of their corresponding quark. Quarks always exist in combination; free quarks cannot exist. A baryon, such as a proton or neutron, consists of three.
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"quark." World Encyclopedia. 2005. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. "quark." World Encyclopedia. 2005. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O142-quark.html "quark." World Encyclopedia. 2005. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-quark.html |
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quark
quark in physics, any of a number of subatomic particles carrying a fractional electric charge, postulated as building blocks of the hadrons. Quarks have not been directly observed but theoretical predictions based on their existence have been confirmed experimentally. The name (originally quork) was invented in the 1960s by Murray Gell-Mann; it was changed by association with the line ‘Three quarks for Muster Mark’ in Joyce's Finnegans Wake (1939).
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ELIZABETH KNOWLES. "quark." The Oxford Dictionary of Phrase and Fable. 2006. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. ELIZABETH KNOWLES. "quark." The Oxford Dictionary of Phrase and Fable. 2006. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O214-quark.html ELIZABETH KNOWLES. "quark." The Oxford Dictionary of Phrase and Fable. 2006. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O214-quark.html |
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quark
quark1 / kwärk/ • n. Physics any of a number of subatomic particles carrying a fractional electric charge, postulated as building blocks of the hadrons. Quarks have not been directly observed, but theoretical predictions based on their existence have been confirmed experimentally. quark2 • n. a type of low-fat curd cheese. |
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"quark." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. "quark." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O999-quark.html "quark." The Oxford Pocket Dictionary of Current English. 2009. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-quark.html |
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quark
quark (quarg) Originally German; very low‐fat cheese made from skim milk; contains 80% water; a 100‐g portion is a good source of protein and vitamin B12, a source of vitamin B2, with only a trace of fat, contains 40 mg of sodium and 90 mg of calcium and supplies 80 kcal (325 kJ).
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DAVID A. BENDER. "quark." A Dictionary of Food and Nutrition. 2005. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. DAVID A. BENDER. "quark." A Dictionary of Food and Nutrition. 2005. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O39-quark.html DAVID A. BENDER. "quark." A Dictionary of Food and Nutrition. 2005. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O39-quark.html |
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quark
quark : see elementary particles . |
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"quark." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. "quark." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1E1-X-quark.html "quark." The Columbia Encyclopedia, 6th ed.. 2008. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-X-quark.html |
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quark
quark •arc, ark, Bach, bark, barque, Braque, Clark, clerk, dark, embark, hark, impark, Iraq, Ladakh, Lamarck, lark, macaque, marc, mark, marque, narc, nark, Newark, park, quark, sark, shark, snark, spark, stark, Vlach
•matriarch, patriarch
•tanbark • ringbark • stringy-bark
•Offenbach • ironbark • oligarch
•salesclerk • titlark • skylark
•meadowlark • woodlark • mudlark
•landmark • checkmark • Denmark
•benchmark • waymark • trademark
•seamark • Bismarck • telemark
•tidemark • Kitemark • pockmark
•Ostmark • hallmark • Goldmark
•Deutschmark • bookmark • footmark
•earmark • watermark • birthmark
•anarch • car park • skatepark
•ballpark
•Petrarch, tetrarch
•hierarch, squirearch
•exarch • Pesach • loan shark
•Plutarch • aardvark
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"quark." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. "quark." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O233-quark.html "quark." Oxford Dictionary of Rhymes. 2007. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O233-quark.html |
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