A treatment fluid may comprise: a water having hardness at about 300 ppm or greater, a plurality of particulates, a swellable clay, a chelating agent at about 0.01% to about 5% by weight of the water (BWOW); and an alkali metal base at about 0.01% to about 5% BWOW, wherein the chelating agent and alkali metal base reduce the negative effect of the water on hydrating swellable clays.

A treatment fluid may comprise: a water having hardness at about 300 ppm or greater, a plurality of particulates, a swellable clay, a chelating agent at about 0.01% to about 5% by weight of the water (BWOW); and an alkali metal base at about 0.01% to about 5% BWOW, wherein the chelating agent and alkali metal base reduce the negative effect of the water on hydrating swellable clays.

The invention relates to the use of a building composition marker comprising at least one alpha-amino acid, alpha-amino acid salt or a mixture thereof in a building composition. The invention also relates to a building composition comprising such a building composition marker, and to a process for producing the building composition. The invention further relates to a building composition marker comprising at least one alpha-amino acid, alpha-amino acid salt or mixture thereof, and one or more components selected from:vinyl ester homopolymers, vinyl ester copolymers comprising one or more vinyl ester units and one or more monomer units from the group selected from olefins, vinylaromatics, vinyl halides, acrylic esters, methacrylic esters, monoesters or diesters of fumaric and/or maleic acid, or silicon-functional monomers; (meth)acrylic ester homopolymers, (meth)acrylic ester copolymers comprising one or more (meth)acrylic ester units and one or more monomer units from the group of vinylaromatics, vinyl halides, monoesters or diesters of fumaric and/or maleic acid, or silicon-functional monomers; homopolymers or copolymers of dienes and also of olefins, diene copolymers comprising one or more diene units and one or more monomer units from the group selected from vinyl halides, (meth)acrylic esters, esters of fumaric or maleic acid, and vinylaromatics; homopolymers of vinylaromatics; homopolymers of vinyl halides; andpolysaccharides, polysaccharide ethers, and mixtures thereof.

The invention relates to the use of a building composition marker comprising at least one alpha-amino acid, alpha-amino acid salt or a mixture thereof in a building composition. The invention also relates to a building composition comprising such a building composition marker, and to a process for producing the building composition. The invention further relates to a building composition marker comprising at least one alpha-amino acid, alpha-amino acid salt or mixture thereof, and one or more components selected from:vinyl ester homopolymers, vinyl ester copolymers comprising one or more vinyl ester units and one or more monomer units from the group selected from olefins, vinylaromatics, vinyl halides, acrylic esters, methacrylic esters, monoesters or diesters of fumaric and/or maleic acid, or silicon-functional monomers; (meth)acrylic ester homopolymers, (meth)acrylic ester copolymers comprising one or more (meth)acrylic ester units and one or more monomer units from the group of vinylaromatics, vinyl halides, monoesters or diesters of fumaric and/or maleic acid, or silicon-functional monomers; homopolymers or copolymers of dienes and also of olefins, diene copolymers comprising one or more diene units and one or more monomer units from the group selected from vinyl halides, (meth)acrylic esters, esters of fumaric or maleic acid, and vinylaromatics; homopolymers of vinylaromatics; homopolymers of vinyl halides; andpolysaccharides, polysaccharide ethers, and mixtures thereof.

The present application provides a gas-generating aqueous fluid containing a gas-generating compound like an azo compound, and an organic amine like a primary, secondary or tertiary amine, a hydrazine, a hydrazide, or a semicarbazide. The aqueous fluid may also a viscosifler, and a foaming surfactant. The present application also provides a method of using the gas-generating composition to modulate density of a wellbore fluid for use in downhole applications. The method optionally includes adding an oxidizer to the wellbore fluid.

The present application provides a gas-generating aqueous fluid containing a gas-generating compound like an azo compound, and an organic amine like a primary, secondary or tertiary amine, a hydrazine, a hydrazide, or a semicarbazide. The aqueous fluid may also a viscosifler, and a foaming surfactant. The present application also provides a method of using the gas-generating composition to modulate density of a wellbore fluid for use in downhole applications. The method optionally includes adding an oxidizer to the wellbore fluid.

An example cement includes a naturally occurring silicate bound in an organic binder, a metal oxide, and a chemical activator. The chemical activator is in an effective amount, for dissolving the binder, at least in part, so that the silicate reacts with other components of the cement, the silicate participates in crystal growth; and the cement is a structural load bearing cement.

An example cement includes a naturally occurring silicate bound in an organic binder, a metal oxide, and a chemical activator. The chemical activator is in an effective amount, for dissolving the binder, at least in part, so that the silicate reacts with other components of the cement, the silicate participates in crystal growth; and the cement is a structural load bearing cement.

Disclosed is a composite gypsum board comprising a board core comprising set gypsum sandwiched between face and back cover sheets. The composite gypsum board also comprises an intermediate sheet between the board core and the face cover sheet, with a thin, dense gypsum layer disposed between the intermediate sheet and the face cover sheet. Optionally, a second dense gypsum layer can be disposed between a first major side of the board core and the back cover sheet. Also disclosed is a method of preparing a composite gypsum board in which an intermediate sheet is applied over a dense gypsum layer disposed on a face cover sheet. A back cover sheet is applied to the other major side of the board core, with a second dense gypsum layer optionally disposed therebetween.

Disclosed is a composite gypsum board comprising a board core comprising set gypsum sandwiched between face and back cover sheets. The composite gypsum board also comprises an intermediate sheet between the board core and the face cover sheet, with a thin, dense gypsum layer disposed between the intermediate sheet and the face cover sheet. Optionally, a second dense gypsum layer can be disposed between a first major side of the board core and the back cover sheet. Also disclosed is a method of preparing a composite gypsum board in which an intermediate sheet is applied over a dense gypsum layer disposed on a face cover sheet. A back cover sheet is applied to the other major side of the board core, with a second dense gypsum layer optionally disposed therebetween.