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The international Radura logo, used to show a food has been treated with ionizing radiation. A portable, trailer-mounted food irradiation machine, c. 1968 Food irradiation (sometimes American English: radurization; British English: radurisation) is the process of exposing food and food packaging to ionizing radiation, such as from gamma rays, x-rays, or electron beams.
The radiation source is deemed less than a Category 3 on the International Atomic Energy Agency’s scale — which means it is “very unlikely to cause permanent injury to individuals or contain ...
A radioactive source is a known quantity of a radionuclide which emits ionizing radiation, typically one or more of the radiation types gamma rays, alpha particles, beta particles, and neutron radiation. Sources can be used for irradiation, where the radiation performs a significant ionising function on a target material, or as a radiation ...
Isotopic analysis of hair is an important source of information for archaeologists, providing clues about the ancient diets and differing cultural attitudes to food sources. [ 19 ] A number of other environmental and physiological factors can influence the nitrogen isotopic composition at the base of the food web (i.e. in plants) or at the ...
Archaeological materials, such as bone, organic residues, hair, or sea shells, can serve as substrates for isotopic analysis. Carbon, nitrogen and zinc isotope ratios are used to investigate the diets of past people; these isotopic systems can be used with others, such as strontium or oxygen, to answer questions about population movements and cultural interactions, such as trade.
Prior to industrial processes, the only sources of such energy were solar radiation and electrical discharges. [1] Utilizing a large amount of metabolic energy and the enzyme nitrogenase , some bacteria and cyanobacteria convert atmospheric N 2 to NH 3 , a process known as biological nitrogen fixation (BNF). [ 4 ]
Nitrogen-14 is the source of naturally-occurring, radioactive, carbon-14. Some kinds of cosmic radiation cause a nuclear reaction with nitrogen-14 in the upper atmosphere of the Earth, creating carbon-14, which decays back to nitrogen-14 with a half-life of 5700(30) years .
Alpha particle, beta particle, and gamma ray radioactive emissions are industrially useful. Most sources of these are synthetic radioisotopes. Most sources of these are synthetic radioisotopes. Areas of use include the petroleum industry , industrial radiography , homeland security , process control , food irradiation and underground detection.