Abstract: A method and composition for cementing a well by combining water, blast furnace slag and a phosphate ion-containing compound to form a cement slurry, displacing the cement slurry into the well, and allowing the cement slurry to set.

Abstract: Extrema in intensive physical properties in a multicomponent fluid system having at least four components, which system exhibits three phases in equilibrium are located by analyzing each of the three phases or an "averaged" representation of the three phases for the concentration of each of the components and thereafter subjecting the resulting analysis to a Gram-Schmidt Orthogonalization to determine the composition of at least one pseudocomponent which is orthogonal to the other components. By this means it is possible to go more quickly in a direction whereby a property in question changes most rapidly. such techniques have wide applicability in optimizing compositions for a desired intensive property such as interfacial tension. This can be useful in designing surfactant systems for oil recovery, for instance.