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Trace radionuclides are those that occur in tiny amounts in nature either due to inherent rarity, or to half-lives that are significantly shorter than the age of the Earth. Synthetic isotopes are not naturally occurring on Earth, but they can be created by nuclear reactions.
Radionuclides of familiar elements such as carbon can serve as tracers because they are chemically very similar to the non-radioactive nuclides, so most chemical, biological, and ecological processes treat them in a near identical way. One can then examine the result with a radiation detector, such as a geiger counter, to determine where the atoms one has provided have ended up. For example, one might culture plants in an environment in which the carbon dioxide contained radioactive carbon; then the parts of the plant that had laid down atmospheric carbon would be radioactive.
In medicine, radionuclides are used for diagnosis and research. Radioactive chemical tracers emit gamma rays which provides diagnostic information about a person's anatomy and the functioning of specific organs. Radiotherapy also uses radiation in the treatment of some illnesses, such as cancer. More powerful gamma sources are used to steriliseSterilisation is the elimination of all transimissable agents (such as bacteria, prions and viruses) from a surface or piece of equipment. This is different from disinfection, where only organisms that can cause disease are removed by a disinfectant. syringes and other medical equipment. About one in two people in Western countries are likely to experience the benefits of nuclear medicine in their lifetime.
In food preservationMain food preservation methods Method Effect on microbial growth or survival Refrigeration or chilling Low temperature to retard growth Freezing Low temperature and reduction of water activity to prevent growth Drying, curing and conserving Reduction in w, radiation is used to stop the sprouting of root crops after harvesting, to kill parasites and pests, and to control the ripening of stored fruit and vegetables.
In agricultureFarming, ploughing rice paddy, in Indonesia Agriculture is the process of producing food, feed, fiber and other desired products by cultivation of certain plants and the raising of domesticated animals (livestock). Agriculture is also known as farming . and animal husbandryAnimal husbandry is the agricultural practice of breeding and raising livestock. As such, it is a vital skill for farmers, and in many ways as much art as it is science. The science of animal husbandry, called animal science is taught in many universities, radionuclides also play an important role. They are used to produce high intake of crops, disease and weather resistant varieties of crops, to study how fertilisers and insecticides work, and to improve the production and health of domestic animals.
IndustriallyFor other uses of this term, see Industry (disambiguation An industry is an area of economic production which involves large amounts of upfront capital investment before any profit can be realized. The most successful industries in a given sector tend, to, and in miningSilver City, New Mexico is an open-pit copper mine Mining is the extraction of valuable minerals or other geological materials from the earth, usually (but not always) from an ore body, vein or (coal) seam. Materials commonly recovered by mining include b, radionuclides are used to examine welds, to detect leaks, to study the rate of wear of metals, and for on-stream analysis of a wide range of minerals and fuels.Most household smoke detectorA smoke detector is a safety device that detects airborne smoke and issues an audible alarm, thereby alerting nearby people to the danger of fire. Most smoke detectors work either by optical detection or by ionization, but some of them use both detections use radionuclides containing americiumAmericium is a synthetic element in the periodic table that has the symbol Am and atomic number 95. A radioactive metallic element, americium is an actinide that was obtained by bombarding plutonium with neutrons and was the fourth transuranic element to formed in nuclear reactors, saving many lives.
Environmentally, radionuclides are used to trace and analyse pollutants, to study the movement of surface water, and to measure water runoffs from rain and snow, as well as the flow rates of streams and rivers.Natural radionuclides can be used in archaeology and in paleontology to measure ages. When radioactive carbon, for example, is in the atmosphere, it rapidly becomes separated from its decay products. Once it is bound up in a solid, such as wood or paper, its decay products must remain in place. So by measuring how much of these decay products has accumulated, one can estimate the time when the carbon was captured into solid form.