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  2. Isotope dilution - Wikipedia

    en.wikipedia.org/wiki/Isotope_dilution

    All isotopes of a given element have the same number of protons in each atom. The term isotope is formed from the Greek roots isos (ἴσος "equal") and topos (τόπος "place"), meaning "the same place"; thus, the meaning behind the name is that different isotopes of a single element occupy the same position on the periodic table.

  3. Isotopic shift - Wikipedia

    en.wikipedia.org/wiki/Isotopic_shift

    H NMR spectrum of a solution of HD (labeled with red bars) and H 2 (blue bar). The 1:1:1 triplet arises from the coupling of the 1 H nucleus (I = 1/2) to the 2 H nucleus (I = 1). In NMR spectroscopy, isotopic effects on chemical shifts are typically small, far less than 1 ppm, the typical unit for measuring shifts. The 1 H NMR signals for 1 H 2 ...

  4. Beryllium-10 - Wikipedia

    en.wikipedia.org/wiki/Beryllium-10

    Beryllium-10 (10 Be) is a radioactive isotope of beryllium. It is formed in the Earth's atmosphere mainly by cosmic ray spallation of nitrogen and oxygen. [ 3 ] [ 4 ] [ 5 ] Beryllium-10 has a half-life of 1.39 × 10 6 years, [ 6 ] [ 7 ] and decays by beta decay to stable boron-10 with a maximum energy of 556.2 keV.

  5. Reference materials for stable isotope analysis - Wikipedia

    en.wikipedia.org/wiki/Reference_materials_for...

    The δ values and absolute isotope ratios of common reference materials are summarized in Table 1 and described in more detail below. Alternative values for the absolute isotopic ratios of reference materials, differing only modestly from those in Table 1, are presented in Table 2.5 of Sharp (2007) [1] (a text freely available online), as well as Table 1 of the 1993 IAEA report on isotopic ...

  6. Isotope analysis - Wikipedia

    en.wikipedia.org/wiki/Isotope_analysis

    Archaeological materials, such as bone, organic residues, hair, or sea shells, can serve as substrates for isotopic analysis. Carbon, nitrogen and zinc isotope ratios are used to investigate the diets of past people; these isotopic systems can be used with others, such as strontium or oxygen, to answer questions about population movements and cultural interactions, such as trade.

  7. Hydrogen isotope biogeochemistry - Wikipedia

    en.wikipedia.org/wiki/Hydrogen_isotope...

    The amount of liquid-vapor equilibrium fractionation for hydrogen isotopes is about 8x that of oxygen isotopes at Earth surface temperatures, which reflects the relative mass differences of the two isotope systems: 2 H is 100% heavier than 1 H, 18 O is 12.5% heavier than 16 O. Above the boundary layer, there is a transition zone with relative ...

  8. Isotopes of moscovium - Wikipedia

    en.wikipedia.org/wiki/Isotopes_of_moscovium

    Five SF activities were observed, all occurring in the niobium-like fractions and none in the tantalum-like fractions, proving that the product was indeed isotopes of dubnium. In a series of experiments between October 2010 – February 2011, scientists at the FLNR studied this reaction at a range of excitation energies.

  9. Isotopes of neon - Wikipedia

    en.wikipedia.org/wiki/Isotopes_of_neon

    with a half-life of 770(300) ys (7.7(3.0) × 10 −22 s). See isotopes of carbon for notes about the measurement. Light radioactive neon isotopes usually decay to fluorine or oxygen , while heavier ones decay to sodium .