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Mercury and Stable Isotopes of Carbon and Nitrogen in Mink
Environmental Toxicology and Chemistry, 2007Abstract Total Hg concentrations and values of stable isotopes (δ15N, δ13C) in tissues of mink (Mustela vison) captured in Rhode Island (USA) during winters of 1999 to 2004 were statistically distinct based on location. Mink captured in salt marsh environments (salt marsh group mink [SMGM]) had significantly lower mean Hg concentrations ...
James L, Lake +4 more
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Stable Isotope Geochemistry of Various Carbonates
John Heinrichs Scholarly & Creative Activities Day, 2021This submission is unavailable.
Jenna Howard +5 more
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The separation of stable isotopes of carbon
Russian Chemical Reviews, 1989The present state of work on the separation of carbon isotopes by diffusion, fractional distillation, chemical isotopic exchange, and the selective excitation and dissociation of molecules in electrical discharges or in the field of laser radiation has been examined.
E D Oziashvili, A S Egiazarov
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Stable Carbon and Nitrogen Isotopic
Aquatic Geochemistry, 2004The perennially ice-covered lakes in the McMurdo Dry Valleys, Antarctica, are part of the coldest and driest ecosystem on earth. To understand lacustrine carbon and nitrogen cycling in this end-member ecosystem, and to define paleolimnological proxies for ice-covered lakes, we measured the stable carbon and nitrogen isotopic composition of particulate ...
Jennifer Lawson +4 more
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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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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 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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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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Synthesis of carbon‐14 and stable isotope labeled Censavudine
Journal of Labelled Compounds and Radiopharmaceuticals, 2022Censavudine is a nucleoside reverse transcriptase inhibitor (NRTI) explored clinically by Bristol Myers Squibb for the treatment of human immunodeficiency virus‐1 (HIV‐1). As part of the development process, a carbon‐14 labeled analog was synthesized for use in a human absorption, distribution, metabolism, and excretion (ADME) study.
Richard C. Burrell +4 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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