from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. A minor stable isotope of oxygen, 188O, having eight protons and ten neutrons; it amounts to about 0.2% of the element in nature


Sorry, no etymologies found.


  • Kamen used the isotope oxygen-18 to trace the chemical's role in the process, confirming that that the oxygen created during photosynthesis comes only from the water molecules.

    Kamen, Martin David

  • Naturally occurring oxygen-18 (18O) is stable and available commercially, as is water (H2O with 15% 18O).


  • DMS____________Dimethyl Sulfide, a precursor of various atmospheric sulfur compounds dO18, 'ˆ‚O18_____Change in oxygen-18 isotope level

    NOAA Gridded Data « Climate Audit

  • Other studies used the ratio of oxygen-18 to oxygen-16 δ 18O in the shells, so Mg/Ca provides a parallel measure.

    Ars Technica

  • In this case, they found a slight excess in the abundance of oxygen-17 and oxygen-18 compared with rocks from Earth, just as we would expect from a Martian rock. - Telegraph online, Daily Telegraph and Sunday Telegraph

  • Using an instrument called a mass spectrometer think of it as an atomic weighing machine, they studied the relative abundance in the meteorite's silicate minerals of three isotopes of oxygen - oxygen-16, oxygen-17 and oxygen-18. - Telegraph online, Daily Telegraph and Sunday Telegraph

  • As a result, as clouds rise they become depleted in oxygen-18.

    Scientific American

  • Because water containing oxygen-18 is heavier than that containing the more common isotope oxygen-16, it falls - and condenses - more easily from clouds.

    Scientific American

  • At issue is the ratio of two stable oxygen isotopes - oxygen-16 and oxygen-18 - in lumps of carbonate mineral found in sediments from dried-out mountain lakes.

    Scientific American

  • However, these rapid-rise findings were based on modern measurements of oxygen-18 levels in rainwater collected at various elevations, Poulsen says, and there's no guarantee that the ratio of the two isotopes was the same in rainwater millions of years ago.

    Scientific American


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