ash element

例句：

1. 1. The ash from the volcanic eruption is a valuable resource for metallurgy.
   火山爆发产生的灰烬是冶金的重要资源。
2. 2.The ash residue left after combustion is often used as a soil amendment.
   燃烧后留下的灰烬残渣常被用作土壤改良剂。
3. 3. The study of ash elements in rocks and minerals is essential to understanding their chemical composition.
   岩石和矿物中灰烬元素的研究表明了它们的化学成分。