Results 11 to 20 of about 104,171 (282)
Carbon Isotopic Chemistry [PDF]
Symposium - International Astronomical Union, 1992 Isotopic molecular abundances are used to interpret Galactic chemical evolution and the properties of interstellar clouds. The isotopic chemistry of carbon plays an important role in the interpretation of these measurements. This paper reviews the recent measurements of the carbon twelve to thirteen ratio across the Galaxy and the isotopic chemistry.
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Yankuang ceshi, 2020 BACKGROUND Organic carbon and nitrogen stable isotopes (δ13C, δ15N) in marine sediments are used as effective indicators to trace the changes of air, temperature, precipitation and other parameters in different geological time. Elemental analysis-isotope
CHANG Wen-bo +3 more
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Carbon isotopic fractionation in molecular clouds [PDF]
Astronomy & Astrophysics, 2020 Context. Carbon fractionation has been studied from a theoretical point of view with different models of time-dependent chemistry, including both isotope-selective photodissociation and low-temperature isotopic exchange reactions. Aims. Recent chemical models predict that isotopic exchange reactions may lead to a depletion of 13C in nitrile-bearing ...
Francesco Fontani +5 more
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Dry season limnological conditions and basin geology exhibit complex relationships with δ13C and δ15N of carbon sources in four Neotropical floodplains. [PDF]
PLoS ONE, 2017 Studies in freshwater ecosystems are seeking to improve understanding of carbon flow in food webs and stable isotopes have been influential in this work.
Gustavo H Zaia Alves +3 more
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Frontiers in Marine Science, 2019 Blue carbon is the organic carbon in oceanic and coastal ecosystems that is captured on centennial to millennial timescales. Maintaining and increasing blue carbon is an integral component of strategies to mitigate global warming.
Nathan R. Geraldi +12 more
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Isotopes in pyrogenic carbon: A review [PDF]
Organic Geochemistry, 2012 Pyrogenic carbon (PC; also known as biochar, charcoal, black carbon and soot) derived from natural and anthropogenic burning plays a major, but poorly quantified, role in the global carbon cycle. Isotopes provide a fundamental fingerprint of the source of PC and a powerful tracer of interactions between PC and the environment.
Bird, M.I., Ascough, P.L.
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Modern Strategies for Carbon Isotope Exchange
Angewandte Chemie, 2023 AbstractIn contrast to stable and natural abundant carbon‐12, the synthesis of organic molecules with carbon (radio)isotopes must be conceived and optimized in order to navigate through the hurdles of radiochemical requirements, such as high costs of the starting materials, harsh conditions and radioactive waste generation.
Labiche, Alexandre +4 more
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Features and origin of oil degraded gas of Santai field in Junggar Basin, NW China
Petroleum Exploration and Development, 2015 Based on comprehensive analysis of the natural gas composition, carbon isotopes and associated oil carbon isotopes, saturated hydrocarbon chromatography, and gas chromatography-mass spectrography, the features and formation mechanisms of natural gas in ...
Jungang LU +10 more
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A pilot study of stable isotope fractionation in Bombyx mori rearing
Scientific Reports, 2023 Hydrogen, oxygen, carbon, and nitrogen isotopes derived from three different strains of silkworms at different life stages involved in silkworm rearing, were measured to understand the fractionation characteristics of stable isotopes at different stages ...
Hao Li +11 more
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Diversity, 2020 The input of new nutrients by upwelling in shelf waters, and the associated carbon and nitrogen fluxes, can be traced by their stable isotope signatures in organic matter.
Antonio Bode +2 more
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