منابع مشابه
Presolar Grains from the Qingzhen (eh3) Meteorite
A 28 g sample of the Qingzhen enstatite (EH3) chondrite was subjected to chemical and physical separation procedures to yield several grain-size residues. Ion mapping of isotopes of Si, O, and C in the ion microprobe of two size fractions (QZR4: 0.4–0.8 lm; QZR5: 0.8–2 lm) identified 55 30Si-depleted candidates out of 37,917 Si-rich grains and six 18O-depleted grains out of 54,410 oxides. Subse...
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There are several meteoritic noble gas components whose isotopic abundances are distinctly different from the solar abundance. One of these components, Ne-E(L), is a 22Ne-rich component carried by presolar graphite. Neon-22 is dominantly from the radiogenic decay of 22Na (T1/2 = 2.6 a), but it also contains 22Ne produced by 14N(α, γ )18F(e+ν)18O(α, γ )22Ne. The proportions of 22Ne from the two ...
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ژورنال
عنوان ژورنال: Meteoritics & Planetary Science
سال: 2002
ISSN: 1086-9379,1945-5100
DOI: 10.1111/j.1945-5100.2002.tb00899.x