isotope occurrence

См. также в других словарях:

• Isotope — This article is about the atomic variants of chemical elements. For the British jazz fusion band, see Isotope (band). Isotopes redirects here. For the minor league baseball team, see Albuquerque Isotopes. Isotopes are variants of atoms of a… …   Wikipedia

• isotope — isotopic /uy seuh top ik/, adj. isotopically, adv. /uy seuh tohp /, n. Chem. any of two or more forms of a chemical element, having the same number of protons in the nucleus, or the same atomic number, but having different numbers of neutrons in… …   Universalium

• isotope dilution — ▪ chemistry       radiochemical method of analysis for measuring the mass and quantity of an element in a substance. The procedure involves adding to a substance a known quantity of a radioisotope of the element to be measured and mixing it with… …   Universalium

• Chemical shift — In nuclear magnetic resonance (NMR) spectroscopy, the chemical shift is the resonant frequency of a nucleus relative to a standard. Often the position and number of chemical shifts are diagnostic of the structure of a molecule.[1][2][3] Chemical… …   Wikipedia

• Earth Sciences — ▪ 2009 Introduction Geology and Geochemistry       The theme of the 33rd International Geological Congress, which was held in Norway in August 2008, was “Earth System Science: Foundation for Sustainable Development.” It was attended by nearly… …   Universalium

• Chemical element — The periodic table of the chemical elements A chemical element is a pure chemical substance consisting of one type of atom distinguished by its atomic number, which is the number of protons in its nucleus.[1] Familiar examples of …   Wikipedia

• radioactivity — /ray dee oh ak tiv i tee/, n. Physics, Chem. the phenomenon, exhibited by and being a property of certain elements, of spontaneously emitting radiation resulting from changes in the nuclei of atoms of the element. Also called activity. [1895… …   Universalium

• Caesium — xenon ← caesium → barium Rb ↑ Cs ↓ Fr …   Wikipedia

• 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

• Zinc — This article is about the metallic element. For other uses, see Zinc (disambiguation). copper ← zinc → gallium ↑ Zn ↓ Cd …   Wikipedia

• Radon — This article is about the chemical element. For other uses, see Radon (disambiguation). astatine ← radon → francium Xe ↑ Rn ↓ Uuo …   Wikipedia