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Carbon Isotope Abundance in Meteoritic Carbonates
Science, 1963The C 13 /C 12 ratio in the carbonate minerals of Orgueil, a carbonaceous chondrite, is 6 percent greater than the ratio in any known terrestrial carbon. The effect may be produced by a chemical isotope fractionation involving processes not common on earth, or it may be the result of ...
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Carbon and oxygen isotope microanalysis of carbonate
Rapid Communications in Mass Spectrometry, 2009Abstract Technical modification of the conventional method for the δ 13 C and δ 18 O analysis of 10–30 µg carbonate samples is described.
Tatiana A, Velivetskaya +2 more
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CARBON ISOTOPE RATIOS IN BELOWGROUND CARBON CYCLE PROCESSES
Ecological Applications, 2000Analyses of carbon isotope ratios (δ13C) in soil organic matter (SOM) and soil respired CO2 provide insights into dynamics of the carbon cycle. δ13C analyses do not provide direct measures of soil CO2 efflux rates but are useful as a constraint in carbon cycle models.
Ehleringer, J. +2 more
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1993
The stable isotopes of carbon occur in relatively constant proportions throughout the global carbon pool, with 98.89% comprising 12C, and 13C making up 1.11%. However, small but significant variations occur in the proportion of the heavy isotope 13C incorporated into organic and inorganic matter. These depend on the extent of discrimination against (or
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The stable isotopes of carbon occur in relatively constant proportions throughout the global carbon pool, with 98.89% comprising 12C, and 13C making up 1.11%. However, small but significant variations occur in the proportion of the heavy isotope 13C incorporated into organic and inorganic matter. These depend on the extent of discrimination against (or
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1983
The 13C + 13C total fusion cross section has been determined in the range 3.26 ≤ Ec.m. ≤ 8.0 MeV using Ge(Li) detector measurements of low-lying transitions in the residual nuclei and a statistical model calculation of excited state populations. Six different residual nuclei have been observed and their production yields are given.
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The 13C + 13C total fusion cross section has been determined in the range 3.26 ≤ Ec.m. ≤ 8.0 MeV using Ge(Li) detector measurements of low-lying transitions in the residual nuclei and a statistical model calculation of excited state populations. Six different residual nuclei have been observed and their production yields are given.
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Deuterium Isotope Effect on Carbon Isotope Fractionation in Photosynthesis
Science, 1967Plants grown in D 2 O show a decreased tendency to fractionate carbon-13 during photosynthetic incorporation of carbon dioxide. The isotopic ratio C 13 /C 12 of the tissues of deuterated plants appears to be proportional to the deuterium content of the tissue.
R A, Uphaus, J J, Katz
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Carbon isotope effects in carbonate systems
Geochimica et Cosmochimica Acta, 2004Abstract Global carbon cycle models require a complete understanding of the δ13C variability of the Earth’s C reservoirs as well as the C isotope effects in the transfer of the element among them. An assessment of δ13C changes during CO2 loss from degassing magmas requires knowledge of the melt-CO2 carbon isotope fractionation.
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Carbon Isotopes and Microbial Sediments
2000Microbial sediments of the biolaminated type, generated by the matting behavior of preferentially prokaryotic microbenthos, commonly carry the isotopic signatures of both the primary microbial biomass and of the carbonate of the surrounding sediment matrix.
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