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Stable carbon isotopes in paleoceanography: atmosphere, oceans, and sediments
Earth-Science Reviews, 2019Carbon is one of the key elements in organisms and non-living compounds on Earth. Carbon dioxide and methane are important greenhouse gases in the atmosphere, dissolved inorganic (DIC) and organic carbon (DOC) determine water biogeochemistry, and ...
A. Mackensen, G. Schmiedl
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Stable carbon isotopic composition of biogenic carbonates
Geochimica et Cosmochimica Acta, 1965Abstract The geology and sulfur isotopic composition of epigenetic pyrite of the Gas Hills district, Wyoming, indicate a bacterial origin for these sandstone-type uranium deposits. The δC13 value of epigenetic calcite associated with organic materials, however, is heavier than the isotopic composition of calcite of biogenic native sulfur deposits ...
E.S Cheney, M.L Jensen
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The cycle of carbon and the stable carbon isotopes
Geochimica et Cosmochimica Acta, 1956The following estimates are used: carbonate carbon (A) 2420 ± 560 grammes, C12C13 = 88·55 ± 0·05; organic sedimentary carbon (B) between 0·1–0·5 per cent C in shales, C12C13 = 91·00 ± 0·1θ. The concept “crustal carbon” is defined, and based on the measurements of the isotope ratios of thirty-seven diamonds, nineteen carbonates from Ivigtut, some other ...
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Stable carbon isotopic characteristics of fossil fuels in China
Science of The Total Environment, 2022Good knowledge on the stable carbon isotopic composition (δ13C) of fossil fuels is critical for the estimation of atmospheric CO2 sources. Here, we complied a comprehensive δ13C database including 336 coal, 580 oil, and 1160 natural gas data based on the extensive literature search, and conducted field measurements in two megacities, to characterize ...
Peng, Wang +7 more
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, 2020
High precision deuterium and 13C measurement by continuous flow-IRMS: Organic and position-specific isotope analysis. Carbon isotope effects on key reactions in plant metabolism and 13C-patterns in natural compounds.
H. Griffiths
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High precision deuterium and 13C measurement by continuous flow-IRMS: Organic and position-specific isotope analysis. Carbon isotope effects on key reactions in plant metabolism and 13C-patterns in natural compounds.
H. Griffiths
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Stable carbon isotopes in marine porewaters
Earth and Planetary Science Letters, 1985Abstract We present centimeter-scale porewater δ 13 C profiles from four sites in the Central Equatorial Pacific Ocean, which reveal steep porewater δ 13 C gradients (up to −1.0‰ cm −1 ) at the deep-sea sediment—water interface. We describe the processes controlling porewater carbon isotopic composition and incorporate them into a model of the deep ...
Daniel C. McCorkle +2 more
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Journal of Forensic Sciences, 2008
Abstract: There remains significant uncertainty in illicit marijuana cultivation. We analyzed the δ13C and δ15N of 508 domestic samples from known U.S.A. counties, 31 seized from a single location, 5 samples grown in Mexico and Colombia, and 10 northwest border seizures. For a subset, inflorescences and leaves were analyzed separately.
Jason B, West +2 more
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Abstract: There remains significant uncertainty in illicit marijuana cultivation. We analyzed the δ13C and δ15N of 508 domestic samples from known U.S.A. counties, 31 seized from a single location, 5 samples grown in Mexico and Colombia, and 10 northwest border seizures. For a subset, inflorescences and leaves were analyzed separately.
Jason B, West +2 more
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Assessment of Carbon Allocation with Stable Carbon Isotope Labeling
Agronomy Journal, 1990AbstractLabeling plants with isotopic forms of C allows many processes important to agriculture and/or natural resource management to be studied. Most C‐labelling experiments have employed radioactive 14C, but in recent years regulatory constraints associated with use of radioactive materials appear to have curtailed studies which may have benefited ...
Tony J. Svejcar +2 more
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Behavior of Stable Carbon and Stable Nitrogen Isotopes during Hydrothermal Carbonization of biomass
Journal of Analytical and Applied Pyrolysis, 2018Abstract This work studied the changes of stable isotope compositions (C and N) of diverse biomass feedstocks (loblolly pine, cow manure, and sewage biosolids) as a result of hydrothermal carbonization (HTC), and provides insight into degradation pathways based on these changes.
M. Toufiq Reza +3 more
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The carbon stable isotope composition of pollen
Review of Palaeobotany and Palynology, 2004The d 13 C value of plant tissue is increasingly used to infer environmental and ecological conditions in modern and ancient environments. Isolation techniques and morphological descriptions have been established that characterize plant pollen for the greater part of the Phanerozoic eon.
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