carrier-free — Said of a substance in which a radioactive or other tagged atom is found in every molecule; the highest possible specific activity. * * * car·ri·er free (karґe ər freґ) a term denoting a radioisotope of an element in pure form, i.e.,… … Medical dictionary
carrier — [kar′ē ər] n. [ME carier < carien, CARRY] 1. a person or thing that carries, as one who delivers mail or newspapers, or a train, bus, airplane, etc. 2. a) a person or company in the business of transporting goods or passengers b) a company in… … English World dictionary
carrier — 1. A person or animal that harbors a specific infectious agent in the absence of discernible clinical disease and serves as a potential source of infection. 2. Any chemical capable of accepting an atom … Medical dictionary
carrier-free — /kar ee euhr free /, adj. Chem. (of a radioactive isotope) capable of functioning as a tracer without the use of a carrier. * * * … Universalium
carrier-free — /kar ee euhr free /, adj. Chem. (of a radioactive isotope) capable of functioning as a tracer without the use of a carrier … Useful english dictionary
Molecular laser isotope separation — (MLIS) is a method of isotope separation, where specially tuned lasers are used to separate isotopes of uranium using selective ionization of hyperfine transitions of uranium hexafluoride molecules. It is similar to AVLIS. Its main advantage over … Wikipedia
Environmental radioactivity — is produced by radioactive materials in the human environment. While some radioisotopes, such as strontium 90 (90Sr) and technetium 99 (99Tc), are only found on Earth as a result of human activity, and some, like potassium 40 (40K), are only… … Wikipedia
Positron emission tomography — (PET) is a nuclear medicine imaging technique which produces a three dimensional image or map of functional processes in the body. The system detects pairs of gamma rays emitted indirectly by a positron emitting radionuclide (tracer), which is… … Wikipedia
Life Sciences — ▪ 2009 Introduction Zoology In 2008 several zoological studies provided new insights into how species life history traits (such as the timing of reproduction or the length of life of adult individuals) are derived in part as responses to… … Universalium
Hydrogen — This article is about the chemistry of hydrogen. For the physics of atomic hydrogen, see Hydrogen atom. For other meanings, see Hydrogen (disambiguation). ← hydrogen → helium … Wikipedia
Physiology of dinosaurs — Note: In this article dinosaur means non avian dinosaur, since most experts regard birds as an advanced group of dinosaurs. The physiology of dinosaurs has historically been a controversial subject, particularly thermoregulation. Recently, many… … Wikipedia
