Si AND Mg-Al ISOTOPIC STUDIES OF PRESOLAR GRAPHITE FROM ORGUEIL
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چکیده
Introduction: Last year we reported the successful isolation of presolar graphite from Orgueil and presented C, N, O and Si isotopic ratios on individual graphite grains from seven density fractions, with grain sizes > 1μm (Table 1) [1, 2]. Except for fractions ORG1b and 1h, all fractions analyzed were found to contain presolar carbonaceous grains that are morphologically and isotopically similar to Murchison graphite [3, 4]. These grains exhibit a large range of C isotopic ratios (
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تاریخ انتشار 2006