概括
石中的细粒度钻石显示了与其宿主石类型相关的碳和同位素的变化. 这些内在的差异表明早期太阳星云中的异质分布.
科学领域:
- 宇宙化学 宇宙化学
- 行星科学 行星科学
- 材料科学 材料科学 材料科学
背景情况:
- 细粒度钻石是大量的环恒星尘埃,在原始的石中发现.
- 它们的元素和同位素组成受到宿主石的影响.
- 之前的研究发现了钻石性质的变化,但缺乏明确的解释.
研究的目的:
- 研究不同类型的石中细粒度钻石的元素和同位素特性.
- 为了确定含量和碳同位素成分变化的原因.
- 了解这些钻石在早期太阳星云中的形成和分布.
主要方法:
- 从普通和CM2型石中分离细颗粒钻石.
- 对碳和同位素组成的分析.
- 燃烧实验用于研究碳比率的演变.
主要成果:
- 碳同位素成分在每毫升中介于-32至-38之间.
- 在石类型之间,气丰度差异很大 (0.2~0.9%).
- 已排除了变态脱气作为差异的主要原因.
结论:
- 观察到的钻石组成的变化很可能是从它们的形成中继承的.
- 在凝结过程中,钻石在太阳星云中分布异质.
- 钻石中隐藏的载体不能被排除为一个有助于因素.
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