The leaching process is controlled by mixed steps:the surface chemical reaction and the diffusion passing through the silicon and iron mineral phases.

浸出过程属于混合控制，即表面化学反应与通过不溶硅、铁矿物相的扩散为过程的控制步骤。

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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.

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。

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This initial reaction or oxidation resists further chemical reaction on the metal surface.

初始的反应或氧化可以抵制材料表面再进行化学反应。

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