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Variations in lead isotopic abundances in Sprague-Dawley rat tissues: possible reason of formation. [PDF]
PLoS ONE, 2014 It has been reported in previous research that the lead isotopic composition of blood, urine and feces samples statistically differed from the given lead sources in Sprague-Dawley (SD) rats. However, the reason for this phenomenon is still unclear.
Duojian Liu +3 more
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H2 clumped isotope measurements at natural isotopic abundances. [PDF]
Rapid Commun Mass Spectrom, 2019 RationaleMolecular hydrogen (H2) is an important gas for atmospheric chemistry, and an indirect greenhouse gas due to its reaction with OH. The isotopic composition of H2 (δD) has been used to investigate its atmospheric budget; here we add a new observable, the clumped isotopic signature ΔDD, to the tools that can be used to study the global cycle of ...
Popa ME, Paul D, Janssen C, Röckmann T.
europepmc +9 more sources
Lithium Isotopic Abundances in Metal‐poor Halo Stars [PDF]
, 2006 Very high quality spectra of 24 metal-poor halo dwarfs and subgiants have been acquired with ESO's VLT/UVES for the purpose of determining Li isotopic abundances.
M. Asplund +4 more
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Isotopic ratios and fractionation in the local Universe [PDF]
EPJ Web of Conferences, 2022 The knowledge of isotopic abundances is important in galaxy evolution studies because isotopes provide diagnostics for the chemical enrichment in galaxies over time.
Viti Serena
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A secondary tracer approach to the derivation of galactic cosmic-ray source isotopic abundances
, 1979 E. C. Stone, M. E. Wiedenbeck
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Direct D-atom Incorporation in Radicals: An Overlooked Pathway for Deuterium Fractionation
The Astrophysical Journal, 2023 Direct D-H exchange in radicals is investigated in a quasi-uniform flow employing chirped-pulse millimeter-wave spectroscopy. Inspired by the H-atom catalyzed isomerization of C _3 H _2 reported in our previous study, D-atom reactions with the propargyl (
Nureshan Dias +4 more
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Presolar grain isotopic ratios as constraints to nuclear physics inputs for s-process calculations [PDF]
EPJ Web of Conferences, 2023 The isotopic abundances in presolar SiC grains of AGB origin provide important and precise constraints to those star nucleosynthesis models. By comparing the values of the s-element abundances resulting from calculations with the ones measured in these ...
Palmerini Sara +6 more
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The Astrophysical Journal, 2023 Anomalies in isotopic abundances of Mo and Ru in solar system matter were found to document variable contributions of the nucleosynthetic s -process component. We report isotopic relations of ϵ ^92 Mo versus ϵ ^100 Ru in meteorites from chondritic parent
Kurt Marti +2 more
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Organic vs. conventional grassland management: do (15)N and (13)C isotopic signatures of hay and soil samples differ? [PDF]
PLoS ONE, 2013 Distinguishing organic and conventional products is a major issue of food security and authenticity. Previous studies successfully used stable isotopes to separate organic and conventional products, but up to now, this approach was not tested for organic
Valentin H Klaus +7 more
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The Astrophysical Journal Letters, 2023 GN-z11 is an unusually luminous high-redshift galaxy that was recently observed to have strong nitrogen lines while at the same time lacking traditional signatures of active galactic nucleus activity.
Chris Nagele, Hideyuki Umeda
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