经过了20年的光阴，旧填充物表面有95%的汞元素已经发生了化学反应，它变成了黑辰砂(beta - mercury sulfide)，一种黑色的固体。

After two decades, 95 percent of the elemental mercury on the surface of a filling had gone through a chemical reaction. It became beta-mercury sulfide, a black-colored solid.

youdao

经过了20年的光阴，旧填充物表面有95%的汞元素已经发生了化学反应，它变成了黑辰砂(beta - mercury sulfide)，一种黑色的固体。

After two decades, 95 percent of the elemental mercury on the surface of a filling had gone through a chemical reaction. It became beta-mercury sulfide, a black-colored solid.

youdao