At the mouths of the rivers , fresh water joins the salt water of the sea .
2
中总会掺加那些悲哀的元素。
Happiness by adding those sad there the elements.
3
本文简要介绍了硅灰的特性,着重研究了掺加硅灰后混凝土的物理力学性能以及耐久性。
The paper introduced the characteristics of siliceous lime briefly, and mainly made a study of physical, mechanical and enduring performance of concrete blended with siliceous lime.