体积较小的小行星只不过是一些尘埃和陨石球粒的堆积物，其中这些圆状岩石形成于太阳早期高热量下融熔的尘埃。
Small asteroids are often little more than piles of dust and chondrules, the spherical pebbles of rock that formed from dust which melted in the heat of the young sun.
对所有锐边和焊缝进行倒圆，打磨除去焊接飞溅物。
Round off al rough welds and sharp edges, remove al weld patterns.
综述了烟草重要致香物圆柚酮的合成研究现状，主要讨论了圆柚酮合成的反应原理及一般合成方法。参考文献8篇。
The status of synthesis of nootkatone used as an important tobacco flavoring was reviewed with 8 references. Some reactions and general ways of synthesis were discussed.
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