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  2. Isotopes of oxygen - Wikipedia

    en.wikipedia.org/wiki/Isotopes_of_oxygen

    O, samples enriched with the other stable isotopes can be used for isotope labeling. For example, it was proven that the oxygen released in photosynthesis originates in H 2 O, rather than in the also consumed CO 2, by isotope tracing experiments. The oxygen contained in CO 2 in turn is used to make up the sugars formed by photosynthesis.

  3. δ18O - Wikipedia

    en.wikipedia.org/wiki/Δ18O

    In geochemistry, paleoclimatology and paleoceanography δ 18 O or delta-O-18 is a measure of the deviation in ratio of stable isotopes oxygen-18 (18 O) and oxygen-16 (16 O). It is commonly used as a measure of the temperature of precipitation, as a measure of groundwater/mineral interactions, and as an indicator of processes that show isotopic fractionation, like methanogenesis.

  4. Oxygen isotope ratio cycle - Wikipedia

    en.wikipedia.org/wiki/Oxygen_isotope_ratio_cycle

    Oxygen (chemical symbol O) has three naturally occurring isotopes: 16 O, 17 O, and 18 O, where the 16, 17 and 18 refer to the atomic mass.The most abundant is 16 O, with a small percentage of 18 O and an even smaller percentage of 17 O. Oxygen isotope analysis considers only the ratio of 18 O to 16 O present in a sample.

  5. Equilibrium fractionation - Wikipedia

    en.wikipedia.org/wiki/Equilibrium_fractionation

    Equilibrium isotope fractionation is the partial separation of isotopes between two or more substances in chemical equilibrium. Equilibrium fractionation is strongest at low temperatures, and (along with kinetic isotope effects) forms the basis of the most widely used isotopic paleothermometers (or climate proxies): D/H and 18 O/ 16 O records from ice cores, and 18 O/ 16 O records from calcium ...

  6. Isotope - Wikipedia

    en.wikipedia.org/wiki/Isotope

    Isotope analysis is the determination of isotopic signature, the relative abundances of isotopes of a given element in a particular sample. Isotope analysis is frequently done by isotope ratio mass spectrometry. For biogenic substances in particular, significant variations of isotopes of C, N, and O can occur.

  7. Doubly labeled water - Wikipedia

    en.wikipedia.org/wiki/Doubly_labeled_water

    When cellular respiration breaks down carbon-containing molecules to release energy, carbon dioxide is released as a byproduct. The oxygen atoms in CO 2 exist in equilibrium with the isotopes of oxygen in body water. [6] Therefore if the oxygen in water is labeled with 18 O, then CO 2 produced by

  8. 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.

  9. Category:Isotopes of oxygen - Wikipedia

    en.wikipedia.org/wiki/Category:Isotopes_of_oxygen

    Pages in category "Isotopes of oxygen" The following 22 pages are in this category, out of 22 total. This list may not reflect recent changes. ...