Nuclear for Medicine

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Normal whole body PET/CT scan with FDG-18. The whole body PET/CT scan is commonly used in the detection, staging and follow-up of various cancers.

Nuclear medicine is a branch or specialty of medicine and medical imaging that uses radioactive isotopes (radionucleis) and relies on the process of radioactive decay in the diagnosis and treatment of disease. In nuclear medicine procedures, radionuclides are combined with other chemical compounds or pharmaceuticals to form radiopharmaceuticals) . These radiopharmaceuticals, once administered to the patient, can localize to specific organs or cellular receptors. This unique ability of radiopharmaceticals allow nuclear medicine to diagnose or treat a disease based on the cellular function and physiology rather than relying on the anatomy.

Nuclear Energy

Nuclear energy is released by the splitting (fission) or merging together (fusion) of the nuclei of atom(s). The conversion of nuclear mass to energy is consistent with the mass energy equivalence formula ΔE = Δm.c², in which ΔE = energy release, Δm =mass defect, and c = the speed of light in a vacuum(a physical constant). Nuclear energy was first discovered by French physicist Henri Becquerel in 1896, when he found that photographic plates stored in the dark near uranium were blackened like X-Ray plates, which had been just recently discovered at the time 1895.

Nuclear chemetry can be used as a form of alchemy to turn lead into gold or change any atom to any other atom (albeit through many steps). Radionuclide(radioisotope) production often involves irradiation of another isotope (or more precisely a nuclide), with alpha particle, beta particles, or gamma rays. Iron has the highest binding energy per nucleon of any atom. If an atom of lower average binding energy is changed into an atom of higher average binding energy, energy is given off. The chart shows that fusion of hydrogen, the combination to form heavier atoms, releases energy, as does fission of uranium, the breaking up of a larger nucleus into smaller parts. Stability varies between isotopes: the isotope U-235 is much less stable than the more common U-238.

Nuclear Power

The Susquehanna steam electric, a boiling water reactor. The reactors are located inside the rectangular containment building tower the front of the cooling towers.

Nuclear power is any nuclear energy designed to extract usable energy from atomic nuclei via controlled nuclear reaction. The only method in use today produces power via nuclear fission, though other methods might one day include nuclear fusion and radioactive decay. All utility-scale reactors heat water to produce steam, which is then converted into mechanical work for the purpose of generating electricity or propulation. In 2007, 14% of the world's electricity came from nuclear power. Also, more than 150 nuclear-powered naval vessels have been built, and a few radioisotope rocket have been produced.