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coagulation
coagulation , the collecting into a mass of minute particles of a solid dispersed throughout a liquid (a sol), usually followed by the precipitation or separation of the solid mass from the liquid. The casein in milk is coagulated (curdled) by the addition of acetic acid or citric acid. The albumin in egg white is coagulated by heating. The clotting of blood is another example of coagulation. Coagulation usually involves a chemical reaction. Lyophobic particles (see colloid ) lose their electric charge by reacting with oppositely charged particles. Lyophilic particles undergo a reaction that causes them to lose their solubility. In either case coagulation occurs. The formation of a gel by evaporation or cooling of a sol is usually called gelation rather than coagulation. |
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"coagulation." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 31 May. 2012 <http://www.encyclopedia.com>. "coagulation." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 31, 2012). http://www.encyclopedia.com/doc/1E1-coagulat.html "coagulation." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 31, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-coagulat.html |
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coagulation
coagulation A process involving the denaturation of proteins, the loss of their native, soluble structure, so that they become insoluble; it may be effected by heat, strong acids and alkalis, metals, and other chemicals. Some proteins are coagulated by specific enzymic action; the action of chymosin in cheese making is to coagulate the proteins of milk.
The final stage in blood clotting is the precipitation of insoluble fibrin, formed from the soluble plasma protein fibrinogen. The enzyme responsible is prothrombin, which is normally inactive, but in response to injury is activated by a cascade of events. Vitamin K is required for the synthesis of prothrombin, and clotting requires calcium ions. See also blood plasma. |
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DAVID A. BENDER. "coagulation." A Dictionary of Food and Nutrition. 2005. Encyclopedia.com. 31 May. 2012 <http://www.encyclopedia.com>. DAVID A. BENDER. "coagulation." A Dictionary of Food and Nutrition. 2005. Encyclopedia.com. (May 31, 2012). http://www.encyclopedia.com/doc/1O39-coagulation.html DAVID A. BENDER. "coagulation." A Dictionary of Food and Nutrition. 2005. Retrieved May 31, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O39-coagulation.html |
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coagulation
coagulation The process in which colloidal particles come together irreversibly to form larger masses. Coagulation can be brought about by adding ions to change the ionic strength of the solution and thus destabilize the colloid (see flocculation). Ions with a high charge are particularly effective (e.g. alum, containing Al3+, is used in styptics to coagulate blood). Alum and iron(III) sulphate are also used for coagulation in sewage treatment. Heating is another way of coagulating certain colloids (e.g. boiling an egg coagulates the albumin). See also blood clotting.
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"coagulation." A Dictionary of Biology. 2004. Encyclopedia.com. 31 May. 2012 <http://www.encyclopedia.com>. "coagulation." A Dictionary of Biology. 2004. Encyclopedia.com. (May 31, 2012). http://www.encyclopedia.com/doc/1O6-coagulation.html "coagulation." A Dictionary of Biology. 2004. Retrieved May 31, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O6-coagulation.html |
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coagulation
coagulation The clumping together of colloidal particles to form a large mass; it may be caused by heating (e.g. the cooking of an egg causes the albumin (the ‘white’) to solidify) or by the addition of ions that neutralize the electrical charge which stabilize the colloid. See also BLOOD CLOTTING.
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MICHAEL ALLABY. "coagulation." A Dictionary of Zoology. 1999. Encyclopedia.com. 31 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "coagulation." A Dictionary of Zoology. 1999. Encyclopedia.com. (May 31, 2012). http://www.encyclopedia.com/doc/1O8-coagulation.html MICHAEL ALLABY. "coagulation." A Dictionary of Zoology. 1999. Retrieved May 31, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O8-coagulation.html |
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coagulation
coagulation The clumping together of colloidal particles to form a large mass; it may be caused by heating (e.g. the cooking of an egg causes the albumen (the ‘white’) to solidify) or by the addition of ions that neutralize the electrical charge which stabilizes the colloid.
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MICHAEL ALLABY. "coagulation." A Dictionary of Ecology. 2004. Encyclopedia.com. 31 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "coagulation." A Dictionary of Ecology. 2004. Encyclopedia.com. (May 31, 2012). http://www.encyclopedia.com/doc/1O14-coagulation.html MICHAEL ALLABY. "coagulation." A Dictionary of Ecology. 2004. Retrieved May 31, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O14-coagulation.html |
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coagulation
coagulation (koh-ag-yoo-lay-shŏn) n. the process by which a colloidal liquid changes to a jelly-like mass. See blood coagulation.
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"coagulation." A Dictionary of Nursing. 2008. Encyclopedia.com. 31 May. 2012 <http://www.encyclopedia.com>. "coagulation." A Dictionary of Nursing. 2008. Encyclopedia.com. (May 31, 2012). http://www.encyclopedia.com/doc/1O62-coagulation.html "coagulation." A Dictionary of Nursing. 2008. Retrieved May 31, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O62-coagulation.html |
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