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irradiation
irradiation, an optical phenomenon whereby bright objects viewed against a darker background appear to be bigger than they are; and dark objects viewed against a lighter background appear to be smaller. The sun viewed against the darker background of the sky, and the sky viewed against the normally darker background of the sea, result in irradiation effects for which an allowance should be made when correcting the observed altitude of the sun in celestial navigation. The same conditions apply to moon altitude observations. An interesting effect of irradiation of the moon is often to be seen when it is crescent shaped and the remainder of its surface is faintly illuminated by reflected earth-shine. When the moon is young—not more than three or four days after it is new—this phenomenon is sometimes known, rather poetically, as ‘the old moon in the new moon's arms’.
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"irradiation." The Oxford Companion to Ships and the Sea. 2006. Encyclopedia.com. 29 May. 2012 <http://www.encyclopedia.com>. "irradiation." The Oxford Companion to Ships and the Sea. 2006. Encyclopedia.com. (May 29, 2012). http://www.encyclopedia.com/doc/1O225-irradiation.html "irradiation." The Oxford Companion to Ships and the Sea. 2006. Retrieved May 29, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O225-irradiation.html |
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irradiation
irradiation Exposure to nuclear or electromagnetic radiation. Materials are often irradiated with high-energy neutrons in nuclear reactors, to make them temporarily radioactive. More portable sources of such radiation are radioisotopes such as cobalt-60 and caesium-137, which are used in the irradiation treatment for cancer. Treatment also involves the use of particle accelerator, including proton and neutron beam machines. Ionizing radiation is used in food preservation to destroy bacteria and microorganisms in some foodstuffs, while in other foods, such as soft fruits, it increases shelf-life. The process of irradiation in food technology is still being closely monitored.
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"irradiation." World Encyclopedia. 2005. Encyclopedia.com. 29 May. 2012 <http://www.encyclopedia.com>. "irradiation." World Encyclopedia. 2005. Encyclopedia.com. (May 29, 2012). http://www.encyclopedia.com/doc/1O142-irradiation.html "irradiation." World Encyclopedia. 2005. Retrieved May 29, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-irradiation.html |
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irradiation
irradiation (i-ray-di-ay-shŏn) n.
1. exposure of the body's tissues to ionizing radiation. The source may be background radiation, diagnostic X-rays, radiotherapy, or nuclear accidents. 2. exposure of a substance or object to ionizing radiation. Irradiation of food with gamma rays to kill bacteria is a technique used in food preservation. |
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"irradiation." A Dictionary of Nursing. 2008. Encyclopedia.com. 29 May. 2012 <http://www.encyclopedia.com>. "irradiation." A Dictionary of Nursing. 2008. Encyclopedia.com. (May 29, 2012). http://www.encyclopedia.com/doc/1O62-irradiation.html "irradiation." A Dictionary of Nursing. 2008. Retrieved May 29, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O62-irradiation.html |
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irradiation
ir·ra·di·a·tion / iˌrādēˈāshən/ • n. 1. the process or fact of irradiating or being irradiated. 2. Optics the apparent extension of the edges of an illuminated object seen against a dark background. |
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"irradiation." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 29 May. 2012 <http://www.encyclopedia.com>. "irradiation." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (May 29, 2012). http://www.encyclopedia.com/doc/1O999-irradiation.html "irradiation." The Oxford Pocket Dictionary of Current English. 2009. Retrieved May 29, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-irradiation.html |
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irradiation
irradiation A method of sterilizing and disinfesting foods using ionizing radiation (X‐rays or γ‐rays) to kill micro‐organisms and insects. Also used to inhibit sprouting of potatoes. See also microwave cooking; ultraviolet radiation.
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DAVID A. BENDER. "irradiation." A Dictionary of Food and Nutrition. 2005. Encyclopedia.com. 29 May. 2012 <http://www.encyclopedia.com>. DAVID A. BENDER. "irradiation." A Dictionary of Food and Nutrition. 2005. Encyclopedia.com. (May 29, 2012). http://www.encyclopedia.com/doc/1O39-irradiation.html DAVID A. BENDER. "irradiation." A Dictionary of Food and Nutrition. 2005. Retrieved May 29, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O39-irradiation.html |
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irradiation
irradiation
1. An optical contrast effect that makes a bright object appear larger than it really is when viewed against a darker background. 2. Exposure to any form of electromagnetic radiation or atomic particles. |
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"irradiation." A Dictionary of Astronomy. 1997. Encyclopedia.com. 29 May. 2012 <http://www.encyclopedia.com>. "irradiation." A Dictionary of Astronomy. 1997. Encyclopedia.com. (May 29, 2012). http://www.encyclopedia.com/doc/1O80-irradiation.html "irradiation." A Dictionary of Astronomy. 1997. Retrieved May 29, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O80-irradiation.html |
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irradiation
irradiation Exposure to any form of radiation; often exposure to ionizing radiation is implied. See also food preservation.
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"irradiation." A Dictionary of Biology. 2004. Encyclopedia.com. 29 May. 2012 <http://www.encyclopedia.com>. "irradiation." A Dictionary of Biology. 2004. Encyclopedia.com. (May 29, 2012). http://www.encyclopedia.com/doc/1O6-irradiation.html "irradiation." A Dictionary of Biology. 2004. Retrieved May 29, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O6-irradiation.html |
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