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Irradiation

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Irradiation is the process by which an object is exposed to radiation. An irradiator is a device used to expose an object to radiation, notably gamma radiation, for a variety of purposes.[1] Irradiators may be used for sterilizing medical and pharmaceutical supplies, preserving foodstuffs, alteration of gemstone colors, studying radiation effects, eradicating insects through sterile male release programs, or calibrating thermoluminescent dosimeters (TLDs).[2]

The exposure can originate from various sources, including natural sources. Most frequently the term refers to ionizing radiation, and to a level of radiation that will serve a specific purpose, rather than radiation exposure to normal levels of background radiation. The term irradiation usually excludes the exposure to non-ionizing radiation, such as infrared, visible light, microwaves from cellular phones or electromagnetic waves emitted by radio and television receivers and power supplies.

Applications

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Sterilization

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If administered at appropriate levels, all forms of ionizing radiation can sterilize objects, including medical instruments, disposables such as syringes, and sterilize food. Ionizing radiation (electron beams, X-rays and gamma rays)[3] may be used to kill bacteria in food or other organic material, including blood.[citation needed] Food irradiation, while effective, is seldom used due to problems with public acceptance.[4]

Medicine

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Irradiation is used in diagnostic imaging, cancer therapy and blood transfusion.[5]

In 2011 researchers found that irradiation was successful in the novel theranostic technique involving co-treatment with heptamethine dyes to elucidate tumor cells and attenuate their growth with minimal side effects.[6][7]

Ion implantation

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Ion irradiation is routinely used to implant impurities atoms into materials, especially semiconductors, to modify their properties. This process, usually known as ion implantation, is an important step in the manufacture of silicon integrated circuits.[8]

Ion irradiation

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Ion irradiation means in general using particle accelerators to shoot energetic ions on a material. Ion implantation is a variety of ion irradiation, as is swift heavy ions irradiation from particle accelerators induces ion tracks that can be used for nanotechnology.[9][10]

Industrial chemistry

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A
B
B
B
C
C
The image above contains clickable links
Pure diamonds, before and after irradiation treatment
A Initial (2×2 mm size)
B Irradiated by different doses of 2 MeV electrons
C Irradiated by different doses and then annealed at 800 °C (1,470 °F)

The irradiation process is widely practiced in jewelry industry[11] and enabled the creation of gemstone colors that do not exist or are extremely rare in nature.[12] However, particularly when done in a nuclear reactor, the processes can make gemstones radioactive. Health risks related to the residual radioactivity of the treated gemstones have led to government regulations in many countries.[12][13]

Irradiation is used to cross-link plastics. Due to its efficiency, electron beam processing is often used in the irradiation treatment of polymer-based products to improve their mechanical, thermal, and chemical properties, and often to add unique properties. Cross-linked polyethylene pipe (PEX), high-temperature products such as tubing and gaskets, wire and cable jacket curing, curing of composite materials, and crosslinking of tires are a few examples.

Agriculture

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After its discovery by Lewis Stadler at the University of Missouri, irradiation of seed and plant germplasm has resulted in creating many widely-grown cultivars of food crops worldwide.[14] The process, which consists of striking plant seeds or germplasm with radiation in the form of X-rays, UV waves, heavy-ion beams, or gamma rays, essentially induce lesions of the DNA, leading to mutations in the genome. The UN has been an active participant through the International Atomic Energy Agency. Irradiation is also employed to prevent the sprouting of certain cereals, onions, potatoes and garlic.[15] Appropriate irradiation doses are also used to produce insects for use in the sterile insect technique of pest control.[16]

The U.S. Department of Agriculture's (USDA) Food Safety and Inspection Service (FSIS) recognizes irradiation as an important technology to protect consumers. Fresh meat and poultry including whole or cut up birds, skinless poultry, pork chops, roasts, stew meat, liver, hamburgers, ground meat, and ground poultry are approved for irradiation.[17]

Assassination

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Gheorghe Gheorghiu-Dej, who died of lung cancer in Bucharest on March 19, 1965, may have been intentionally irradiated during a visit to Moscow, due to his political stance.[18]

In 1999, an article in Der Spiegel alleged that the East German MfS intentionally irradiated political prisoners with high-dose radiation, possibly to provoke cancer.[19][20]

Alexander Litvinenko, a secret serviceman who was tackling organized crime in Russia, was intentionally poisoned with polonium-210; the very large internal doses of radiation he received caused his death.

Nuclear industry

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In the nuclear industry, irradiation may refer to the phenomenon of exposure of the structure of a nuclear reactor to neutron flux, making the material radioactive and causing irradiation embrittlement,[21][22] or irradiation of the nuclear fuel.

Security

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During the 2001 anthrax attacks, the US Postal Service irradiated mail to protect members of the US government and other possible targets. This was of some concern to people who send digital media through the mail, including artists. According to the ART in Embassies program, "incoming mail is irradiated, and the process destroys slides, transparencies and disks."[citation needed]

See also

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References

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  1. ^ Irradiator definition. Law Insider (accessed Jan 2023)
  2. ^ Irradiators. United States Department of Agriculture (accessed Jan 2023)
  3. ^ "Food Standards Agency - Irradiated food". Archived from the original on February 7, 2012. Retrieved January 26, 2008.
  4. ^ "Spinach and Peanuts, With a Dash of Radiation" Archived 2017-07-06 at the Wayback Machine article by Andrew Marin in The New York Times February 1, 2009
  5. ^ "Information for patients needing irradiated blood" Archived 2018-11-23 at the Wayback Machine by National Blood Service
  6. ^ Tan X, Luo S, Wang D, et al. A NIR heptamethine Dye with intrinsic cancer targeting, imaging and photosynthesizing properties. Journal of Biomaterials China. 33-7 (2011), pp. 2230-2239.
  7. ^ F. Pene, E. Courtine, A. Cariou, J.P. Mira. Toward theranostics. Crit Care Med, 37 (2009), pp. S50–S58
  8. ^ Meldrum, A.; Haglund, R. F. Jr; Boatner, L. A.; White, C. W. (2001). "Nanocomposite Materials Formed by Ion Implantation". Advanced Materials. 13 (19): 1431–1444. doi:10.1002/1521-4095(200110)13:19<1431::AID-ADMA1431>3.0.CO;2-Z. ISSN 1521-4095.
  9. ^ Rawat, Pankaj Singh; Srivastava, R.C.; Dixit, Gagan; Asokan, K. (December 1, 2020). "Structural, functional and magnetic ordering modifications in graphene oxide and graphite by 100 MeV gold ion irradiation". Vacuum. 182: 109700. Bibcode:2020Vacuu.182j9700R. doi:10.1016/j.vacuum.2020.109700. ISSN 0042-207X. S2CID 225410221.
  10. ^ Andrievskii, R. A. (September 1, 2010). "Effect of irradiation on the properties of nanomaterials". The Physics of Metals and Metallography. 110 (3): 229–240. Bibcode:2010PMM...110..229A. doi:10.1134/S0031918X10090061. ISSN 1555-6190. S2CID 136828233.
  11. ^ Omi, Nelson M.; Rela, Paulo R. (2007). Gemstone Dedicated Gamma Irradiator Development: Proceedings of the INAC 2007 International Nuclear Atlantic Conference (PDF). Associação Brasileira de Energia Nuclear. p. 1. ISBN 978-85-99141-02-1. Archived from the original (PDF) on October 21, 2022. Retrieved October 21, 2022.
  12. ^ a b Hurlbut, Cornelius S.; Kammerling, Robert C. (1991). Gemology (PDF). Wiley-Interscience. p. 170. ISBN 0-471-52667-3. Archived (PDF) from the original on November 4, 2022. Retrieved November 4, 2022 – via LibreTexts.
  13. ^ Nuclear Regulatory Commission (April 2019), Backgrounder on Irradiated Gemstones, The U.S. Nuclear Regulatory Commission, archived from the original on September 1, 2022, retrieved November 12, 2022 Public Domain This article incorporates public domain material from websites or documents of the United States Government.
  14. ^ Ahloowalia, B.S.; Maluszynski, M.; Nichterlein, K. (2004). "Global impact of mutation-derived varieties". Euphytica. 135 (2): 187–204. doi:10.1023/B:EUPH.0000014914.85465.4f. S2CID 34494057.
  15. ^ Bly, J.H. "Electron Beam Processing", Yardley, PA: International Information Associates, 1988.
  16. ^ International Database on Insect Disinfestation and Sterilization Archived 2010-03-28 at the Wayback Machine, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture website, Food and Agriculture Organization of the United Nations, plus the International Atomic Energy Agency.
  17. ^ Irradiation and Food Safety, U.S. Drug and Food Administration. Retrieved Jan. 5, 2010.
  18. ^ "TFP > Alexander Litvinenko Assassination". Archived from the original on July 1, 2011. Retrieved October 18, 2009.
  19. ^ STASI: In Kopfhöhe ausgerichtet. Archived 2013-11-06 at the Wayback Machine Article by Peter Wensierski in Der Spiegel 20/1999, May 17, 1999
  20. ^ Tödliche Strahlung. Die Staatssicherheit der DDR steht im Verdacht, Regimegegner radioaktiv verseucht zu haben. Article by Paul Leonhard in Junge Freiheit April 14, 2000
  21. ^ Materials Ageing – Irradiation Embrittlement. EU Science Hub accessed Jan 2023)
  22. ^ Aitkaliyeva, A.; He, L.; Wen, H.; Miller, B.; Bai, X.M.; Allen, T. (2017). "Irradiation effects in Generation IV nuclear reactor materials". Structural Materials for Generation IV Nuclear Reactors. pp. 253–283. doi:10.1016/B978-0-08-100906-2.00007-0. ISBN 978-0-08-100906-2. OSTI 1476305.
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