这个词是什么意思？
A trace element that constitutes about 27.6% of the earth's crust in the form of SILICON DIOXIDE. It does not occur free in nature. Silicon has the atomic symbol Si, atomic number 14, and atomic weight [28.084; 28.086].
中文名称索引；定义为 MeSH 英文原文，尚未逐条译审。MESH:D012825 · MeSH 2026。
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