| 摘要 |
<p>A foamed, cement slurry comprises an aqueous hydraulic cement slurry containing gas as discrete entrained bubbles and a specific quaternary ammonium compound as a foaming agent which has the formula R R'3N <+>X<-> where X = Cl, Br, I or OH, R = C8-16 aliphatic hydrocarbyl, and R' (independently each occurrence) = C1-3 alkyl or hydroxyethyl and the sum of C atoms in (R+3R') is not greater than 20.</p> |
