Results 11 to 20 of about 12,068,996 (359)
Kinetic nitrogen isotope effects of 18 amino acids degradation during burning processes [PDF]
Scientific ReportsUnderstanding the nitrogen isotopic variations of individual amino acids (AAs) is essential for utilizing the nitrogen isotope values of individual amino acids (δ15N-AA) as source indicators to identify proteinaceous matter originating from biomass ...
Ren-Guo Zhu +7 more
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Ideas and perspectives: the same carbon behaves like different elements – an insight into position-specific isotope distributions [PDF]
Biogeosciences, 2020 It is expected that information on the source, reaction pathway, and reaction kinetics of an organic compound can be obtained from its position-specific isotope compositions or intramolecular isotope distribution (Intra-ID).
Y. He +5 more
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Sulfate triple-oxygen-isotope evidence confirming oceanic oxygenation 570 million years ago
Nature Communications, 2023 The largest negative inorganic carbon isotope excursion in Earth’s history, namely the Ediacaran Shuram Excursion (SE), closely followed by early animal radiation, has been widely interpreted as a consequence of oceanic oxidation.
Haiyang Wang +5 more
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Microbiology Research, 2023 The use of stable isotope-labeled polymers in in situ biodegradation tests provides detailed information on the degradation process. As isotope-labeled raw chemicals are generally expensive, it is desirable to prepare polymer samples with high production
Ramamoorthi M. Sivashankari +2 more
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Isotope effects in liquid water via deep potential molecular dynamics [PDF]
Molecular Physics, 2019 A comprehensive microscopic understanding of ambient liquid water is a major challenge for ab initio simulations as it simultaneously requires an accurate quantum mechanical description of the underlying potential energy surface (PES) as well as ...
Hsin-Yu Ko +6 more
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Isotope Effects and the Atmosphere
Annual Review of Physical Chemistry, 2023 Chemical physics plays a large role in determining the isotopic compositions of gases in Earth's atmosphere, which in turn provide fundamental insights into the sources, sinks, and transformations of atmospheric gases and particulates and their influence on climate.
Julia M, Carlstad, Kristie A, Boering
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An Isotope Effect in Photosynthesis [PDF]
The Journal of Chemical Physics, 1949 In the course of some kinetic studies on photosynthesis of barley seedlings, it has been found that plants utilize C{sup 12}O{sub 2} faster than C{sup 14}O{sub 2}. The plants were placed in a closed system containing an infra-red absorption-cell for the analysis of total CO{sub 2} and an ionization chamber for the determination of C{sup 14}O{sub 2} in ...
Weigl, John W, Calvin, M
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Isotope and Spin Effects Induced by Compression of Paramagnetic Molecules
Physchem, 2022 The zero-point energies (ZPEs) of paramagnetic molecules, free and compressed in a C59N paramagnetic cage, were computed. The excess of energy acquired by molecules under compression depended on the deuterium and tritium isotopes which ranged from 6–8 ...
Irene Barashkova +3 more
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Kinetic Isotope Effects: Interpretation and Prediction Using Degrees of Rate Control
ACS Catalysis, 2020 Kinetic isotope effects (KIEs) have been used for decades in catalysis research as a tool for clarifying reaction mechanisms.
Zhongtian Mao, C. Campbell
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, 2020 . Nitrogen isotope fractionations between nitrogen oxides (NO and NO2 ) play a significant role in determining the nitrogen isotopic compositions ( δ15N ) of atmospheric reactive nitrogen.
Jianghanyang Li +4 more
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