Carbon steel : Steels with a carbon as the principal hardening agent .

碳素钢：以碳作为主要强化剂的钢。

Research on using high-calcium fly ash as the hardening agent of soft soil;

研究了电厂排放的增钙粉煤灰对合成纤维混凝土强度的影响。

After days of failed efforts, technicians managed to stop the leak by injecting a hardening agent called liquid glass into the soil and gravel around the pit.

经过数天失败的尝试，技术人员们试图通过将一种叫做液态玻璃的固化剂注入贮存池周围的土壤和碎石中来阻断泄漏。

By the model, the relationship between dosage and varieties of hardening agent and the strength increasing law of stabilized soil can be interpreted reasonably.

该模型可以较好地反映固化剂掺量和种类与固化土强度增长规律间的关系。