Dictionary

moly cow en · NOUN

Pronunciation

• (Southern-England) audio
• /ˈmoʊli kaʊ̯/ (General-American)
• /ˈməʊli kaʊ̯/ (Received-Pronunciation)

Etymology

Compound of moly (“molybdenum”) (informal) + cow. The term alludes to the fact that the device extracts (“milks”) technetium-99m from molybdenum-99.

Meanings

1. (informal) A device used to extract the metastable isotope technetium-99m from a source of decaying molybdenum-99.
   • When the ⁹⁹Tcₘ isotope is needed for medical imaging purposes, it has to be created on the spot because its half-life is only six hours. This is done using a device filled with longer-lived ⁹⁹Mo, which decays into ⁹⁹Tcₘ, continually replenishing the supply within the device. Because the process of removing the accumulated ⁹⁹Tcₘ is called "milking", the device is informally known as a "moly cow." 2012, Theodore [W.] Gray, The Elements: A Visual Exploration of Every Known Atom in the Universe, New York, N.Y.: Black Dog & Leventhal Publishers, →ISBN:
   • The radioactive isotope molybdenum-99 (half-life of 66 hours) decays to generate technetium-99m, which has a half-life of only six hours and is used in hospitals for medical imaging. The technetium isotope collects in various parts of the body, in particular bone. Scanners detect the radiation from the isotope to create an image, enabling diagnosis. The process uses a device that is filled with Mo-99, which decays into Tc-99m, forming a continuous supply that is ‘milked off’. The device is nicknamed the ‘moly cow’. 2013, Paul Parsons, Gail Dixon, The Periodic Table: A Field Guide to the Elements, London: Quercus, →ISBN:
   • Clearly, transporting the daughter in equilibrium with the parent is a more economical, safer, and environmentally friendlier approach. This is the reason that "technetium generators," dubbed "moly cows," are transported around the globe instead of the ⁹⁹ᵐTc isotope. 2013 November 6, Chary Rangacharyulu, “Radioactivity”, in Physics of Nuclear Radiations: Concepts, Techniques and Applications, Boca Raton, Fla.: CRC Press, →ISBN, page 43:

Forms

Relateds

holy cow

Synonyms

w:technetium-99m generator · technetium cow

wikipedia: Royal Melbourne Institute of Technology · wikipedia: technetium-99m · wikipedia: molybdenum-99