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Reconstructing bulk isotope ratios from compound‐specific isotope ratios
Rapid Communications in Mass Spectrometry, 2010Abstract Carbon isotope analysis by bulk elemental analysis coupled with isotope ratio mass spectrometry has been the mainstay of δ 13 C analyses both at natural abundance and in tracer studies. More recently, compound‐specific isotope analysis (CSIA) has
Douglas J, Morrison +2 more
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Isotope ratio mass spectrometry
The Analyst, 2009Isotope Ratio Mass Spectrometry (IRMS) is a specialized technique used to provide information about the geographic, chemical, and biological origins of substances. The ability to determine the source of an organic substance stems from the relative isotopic abundances of the elements which comprise the material.
Zeland, Muccio, Glen P, Jackson
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Isotope ratios in photosynthetic oxygen
Biochimica et Biophysica Acta (BBA) - Bioenergetics, 1979Axenic suspensions of the fresh water green alga Ankistrodesmus braunii were illuminated under aerobic conditions. The released gas mixture was introduced into the ion source of an isotope mass spectrometer, which recorded the 18O/16O ratio.
H, Metzner, K, Fischer, O, Bazlen
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Isotopic ratios in planetary atmospheres
Advances in Space Research, 1995Recent progress on measurements of isotopic ratios in planetary or satellite atmospheres include measurements of the D/H ratio in the methane of Uranus, Neptune and Titan and in the water of Mars and Venus. Implications of these measurements on our understanding of the formation and evolution of the planets and satellite are discussed.
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Interstellar CNO isotope Ratios
2008In an interpretation of interstellar, circumstellar, and solar system CNO isotope ratios, we find two scenarios which are free of internal inconsistencies. The first requires that the early solar system was enriched by material from massive stars, leading to enhanced 12C/13C and 18O/17O ratios and to a reduced 14N/15N ratio.
C. Henkel +4 more
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Quaternary Research, 2000
AbstractThe GISP2 oxygen isotope record, with its high-resolution detail, yields crucial information on past climate change. The glacial δ18O oscillations of the GISP2 core, with their very fast onsets, are templates of a prototype oscillation of variable duration with an amplitude of 3.9‰.
Minze Stuiver, Pieter M. Grootes
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AbstractThe GISP2 oxygen isotope record, with its high-resolution detail, yields crucial information on past climate change. The glacial δ18O oscillations of the GISP2 core, with their very fast onsets, are templates of a prototype oscillation of variable duration with an amplitude of 3.9‰.
Minze Stuiver, Pieter M. Grootes
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Plutonium isotope ratios in polychaete worms
Nature, 1976WE have noted with interest recent reports which suggest a preferential biological availability of 238Pu over 239+240Pu in terrestrial and aquatic organisms1–4. Although kinetic isotope effects do occur in biological systems for low mass number elements (H, C, N), such effects are generally discounted as the mass number of the element increases.
T M, Beasley, S W, Fowler
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Isotope ratio determination in boron analysis
Biological Trace Element Research, 1998Traditionally, boron (B) isotope ratios have been determined using thermal ionization mass spectrometry (TIMS) and, to some extent, secondary ion mass spectrometry (SIMS). Both TIMS and SIMS use a high-resolution mass analyzer, but differ in analyte ionization methods.
R N, Sah, P H, Brown
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Anomalous Nitrogen Isotope Ratio in Comets
Science, 2003High-resolution spectra of the CN B 2 ∑ + – X 2 ∑ + (0,0) band at 390 nanometers yield isotopic ratios for comets C/1995 O1 (Hale-Bopp) and C/2000 WM1 (LINEAR) as follows: 165 ± 40 and 115 ± 20 for 12
Arpigny, Claude +7 more
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Analytical Chemistry, 2014
Generally, compound-specific isotope analysis of steroids is carried out by gas chromatography combined with isotope ratio mass spectrometry. Thus, a derivatization of the steroids prior to the measurement is compulsory, and a correction of the isotopic data is often necessary.
Zhang, Lijun +8 more
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Generally, compound-specific isotope analysis of steroids is carried out by gas chromatography combined with isotope ratio mass spectrometry. Thus, a derivatization of the steroids prior to the measurement is compulsory, and a correction of the isotopic data is often necessary.
Zhang, Lijun +8 more
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