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Absolute isotope abundances of tin
International Journal of Mass Spectrometry and Ion Physics, 1983Abstract The so-called double-spike technique has been combined with isotope ratio measurements by thermal-ionization mass spectrometry to determine the absolute isotope abundances of natural tin. The experimental conditions for the mass-spectrometric analysis are given, and the procedures for preparation of the double-spike solution and of mixtures ...
C. Devillers, T. Lecomte, R. Hagemann
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Journal of Radioanalytical Chemistry, 1980
The natural relative abundance of iron-58 has been determined by neutron activation analysis using Fe2O3 enriched in the isotope as comparator standard. The value obtained is 0.280∓0.003%. This result, while confirming a recent work, differs significantly from that listed by most commonly used reference tabulations.
W. D. James, J. J. Carni
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The natural relative abundance of iron-58 has been determined by neutron activation analysis using Fe2O3 enriched in the isotope as comparator standard. The value obtained is 0.280∓0.003%. This result, while confirming a recent work, differs significantly from that listed by most commonly used reference tabulations.
W. D. James, J. J. Carni
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The isotopic abundance of antimony
International Journal of Mass Spectrometry and Ion Processes, 1993Abstract With highly enriched isotopes of antimony in the form of 100% pure sesquioxide, a truly calibrated mass spectrometric measurement was carried out on a solid ion source thermal ionization mass spectrometer, yielding an absolute isotopic abundance of 57.213(32)at.% 121Sb and 42.787(32) at.% 123Sb, and the atomic weight of antimony as 121.7597 ...
Tsing-Lien Chang +3 more
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Cosmic Evolution of Isotopic Abundances: Basics
2018The description of the tempo-spatial evolution of the composition of cosmic gas on galactic scales is called ‘galactic chemical evolution’. It combines the knowledge about cosmic sources of nuclei (that is their internal workings and nucleosynthesis yields, and their properties such as frequency of occurrence and spatial distribution), with knowledge ...
Diehl, Roland, Prantzos, Nikos
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Isotopic abundance of meteoritic lithium
Journal of Geophysical Research, 1963Determination of the isotopic abundance of meteoritic lithium by mass spectrometric ...
Makoto Shima, Masatake Honda
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Stable isotope abundances in calcretes
Geological Society, London, Special Publications, 1983Summary About 300 published and unpublished measurements of carbon and oxygen stable isotope ratios of calcretes are compared in an attempt to define general trends. The δ 13 C values of the carbonates range from − 12 to + 4‰ PDB. On a global scale the main factor responsible for the average 13
A. S. Talma, F. Netterberg
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Isotopic magnesium abundances in stars
Monthly Notices of the Royal Astronomical Society, 1988Les spectres a haute resolution du systeme MgH A-X pres de 5130 A fournissent les rapports d'abondance isotopique de 25 Mg/ 24 Mg et 26 Mg/ 24 Mg, pour un echantillon d'etoiles incluant plusieurs etoiles naines et geantes du vieux disque, une etoile baryum classique et une mixte, et une geante faible de la bande ...
A. McWilliam, D. L. Lambert
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Carbon Isotope Abundance in Meteoritic Carbonates
Science, 1963The C 13 /C 12 ratio in the carbonate minerals of Orgueil, a carbonaceous chondrite, is 6 percent greater than the ratio in any known terrestrial carbon. The effect may be produced by a chemical isotope fractionation involving processes not common on earth, or it may be the result of ...
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Interpretation of Lead Isotope Abundances
Nature, 1962I SHOULD like to make further comment about two points which have arisen in the correspondence from Aswathanarayana1,2 and Russell and Slawson3. The first is to support the observations of the latter authors about the importance of proper allowance for mass-spectrometric tail effects.
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Lithium Isotopic Abundances in Stars
2008The Li isotope ratio, 6Li/7Li, in stars can be determined from the isotopic shift in the Li I 670.8 nm resonance line. Because of the small effect this however requires truly precision spectroscopy: spectral resolving power R ≥ 105 and S/N ≥ 500. In this review we discuss the method and what one can learn from Li isotopic abundances in terms of Big ...
Poul Erik Nissen, Martin Asplund
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