| 摘要 |
Additive compositions, made up essentially of a mixture of a salt of a very high molecular weight condensation product of naphthalenesulfonic acid with formaldehyde, containing not less than 35% by weight of the condensation products with a molecular weight greater than 5000, together with a glucopheptonic acid salt, are mixed with hydraulic cement to reduce the water which needs to be added, and to provide improved strength.
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