There may be two possible reaction

在纳米二氧化硅存在下水泥水化过程中可能有两种可能的反应机制。添加纳米二氧化硅可以加速水泥的水化（图 6）。当纳米二氧化硅添加到水泥颗粒中时，H2SiO2-4 形成并与可用的 Ca2+ 离子反应，形成额外的硅酸钙水合物 (C-S-H)，这些 C-S-H 颗粒散布在水中水泥颗粒并作为形成更致密 C-S-H<br>相的种子。总反应如下。

There may be two possible reaction mechanisms during the hydration of cement in presence of nanosilica. Hydration of cement can be accelerated by addition of nanosilica (Fig.6). When nanosilica is added to cement grains, H2SiO2- 4 forms and reacts with the available Ca2+ ions which forms an additional calcium–silicate–hydrate (C–S–H) and these C–S–H particles are spread in the water between the cement particles and serve as seeds for the formation of more compact C– S–H phase. The overall reaction is given below.<br>

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