In accordance with one or more embodiments of the present disclosure, a drilling fluid may include a base fluid and one or more formaldehyde-based resins. The drilling fluid may further comprise one or more water-soluble acid catalyst precursors or the reaction products of such water-soluble acid catalyst precursors. The base fluid may include an aqueous or non-aqueous solution. The present disclosure also describes sealed subterranean petroleum formations that include such drilling fluids and methods for sealing subterranean wellbores by utilizing such drilling fluids.

A lost circulation material (LCM) is provided having an alkaline nanosilica dispersion and an ester activator. The alkaline nanosilica dispersion and the ester activator may form a gelled solid after interaction over a contact period. Methods of lost circulation control using the LCM are also provided.

A lost circulation material (LCM) is provided having an alkaline nanosilica dispersion and an ester activator. The alkaline nanosilica dispersion and the ester activator may form a gelled solid after interaction over a contact period. Methods of lost circulation control using the LCM are also provided.

The present invention relates to a mixture comprising at least one compound comprising an -hydroxy-carboxylic unit, -hydroxy-sulfonic acid unit or -carbonyl-carboxylic unit and at least one water-soluble organic carbonate. The mixture is useful as a hydration control agent in construction chemical compositions comprising an inorganic binder.

This rapid-hardening mortar composition includes: a rapid-hardening admixture; cement; and a fine aggregate, wherein the cement is contained in an amount of 100 parts by mass to 2,000 parts by mass with respect to 100 parts by mass of the rapid-hardening admixture, the rapid-hardening admixture is a composition that contains: calcium aluminate; inorganic sulfate in an amount of 50 parts by mass to 200 parts by mass with respect to 100 parts by mass of the calcium aluminate; and a setting modifier in an amount of 0.1 parts by mass to 10 parts by mass with respect to 100 parts by mass of the calcium aluminate, and an average particle diameter of the calcium aluminate is in a range of 8 m to 100 m, and an average particle diameter of the setting modifier is in a range of 5 m or less.

This rapid-hardening mortar composition includes: a rapid-hardening admixture; cement; and a fine aggregate, wherein the cement is contained in an amount of 100 parts by mass to 2,000 parts by mass with respect to 100 parts by mass of the rapid-hardening admixture, the rapid-hardening admixture is a composition that contains: calcium aluminate; inorganic sulfate in an amount of 50 parts by mass to 200 parts by mass with respect to 100 parts by mass of the calcium aluminate; and a setting modifier in an amount of 0.1 parts by mass to 10 parts by mass with respect to 100 parts by mass of the calcium aluminate, and an average particle diameter of the calcium aluminate is in a range of 8 m to 100 m, and an average particle diameter of the setting modifier is in a range of 5 m or less.

The present invention provides a composition, a gypsum board and their preparation method and the use of ascorbic acid as an anti-sagging additive in a gypsum board. Said gypsum board comprises set gypsum prepared from the composition; while said composition comprises hemi-hydrate gypsum, water and a compound comprising ##STR00001##
group and no carboxylate groups. The set gypsum prepared from the said composition shows better anti-sagging or deformation resisting property. The gypsum board of the present invention is hardly distorted and has stronger stability even in the condition of high humidity, thus improve the quality of the gypsum board to meet the demands of the customer.

The present invention provides a composition, a gypsum board and their preparation method and the use of ascorbic acid as an anti-sagging additive in a gypsum board. Said gypsum board comprises set gypsum prepared from the composition; while said composition comprises hemi-hydrate gypsum, water and a compound comprising ##STR00001##
group and no carboxylate groups. The set gypsum prepared from the said composition shows better anti-sagging or deformation resisting property. The gypsum board of the present invention is hardly distorted and has stronger stability even in the condition of high humidity, thus improve the quality of the gypsum board to meet the demands of the customer.

Various embodiments disclosed relate to compositions including acidic chelator or salt or ester thereof for treatment of subterranean formations including one or more fractures. In various embodiments, the present invention provides a method of treating a subterranean formation. The method includes placing in the subterranean formation a composition including an acidic chelator or a salt or ester thereof. The subterranean formation includes one or more fractures.

Various embodiments disclosed relate to compositions including acidic chelator or salt or ester thereof for treatment of subterranean formations including one or more fractures. In various embodiments, the present invention provides a method of treating a subterranean formation. The method includes placing in the subterranean formation a composition including an acidic chelator or a salt or ester thereof. The subterranean formation includes one or more fractures.