硅酸盐水泥
凡由硅酸盐水泥熟料,0~5%石灰石或粒化高炉矿渣,适量石膏磨细制成的水硬性胶凝材料,称硅酸盐水泥。
A campus emergency ______ occur at any time of the day or night, weekend, or holiday, with little or no warning.
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