The invention provides novel aerated composite materials made from a carbonatable calcium silicate composition, and formulations and methods of manufacture and use thereof, in particular, the use of novel additive mineral compositions in the form of magnesium, magnesium salts or magnesium oxides, to improve physical chemical properties of low density concrete materials. The low density, aerated material is comprised of calcium carbonate (CaCO.sub.3) and silica (SiO.sub.2), as cured products of carbonatable calcium silicate compositions.

Expansive cements for use in cementing subterranean wells comprise water, an inorganic cement and one or more particulate materials that swell upon contact with a water immiscible fluid. The cements may further comprise a water immiscible fluid. Such cements are designed to seal microannuli arising from the presence of water immiscible fluids on casing surfaces, borehole wall surfaces or both.

Expansive cements for use in cementing subterranean wells comprise water, an inorganic cement and one or more particulate materials that swell upon contact with a water immiscible fluid. The cements may further comprise a water immiscible fluid. Such cements are designed to seal microannuli arising from the presence of water immiscible fluids on casing surfaces, borehole wall surfaces or both.

A composition based on a certain chromium-free silicate-based binder is described. The composition is an aqueous solution of lithium-doped potassium silicate in combination with an aluminum or aluminum alloy powder, zinc powder or a combination thereof. The coatings of the present invention are capable of achieving a full cure at temperatures as low as 350-450 degrees F. by the inclusion of a colloidal solution of a nano-sized ceria, thus making the coatings especially suitable for application on temperature sensitive base materials.

A composition based on a certain chromium-free silicate-based binder is described. The composition is an aqueous solution of lithium-doped potassium silicate in combination with an aluminum or aluminum alloy powder, zinc powder or a combination thereof. The coatings of the present invention are capable of achieving a full cure at temperatures as low as 350-450 degrees F. by the inclusion of a colloidal solution of a nano-sized ceria, thus making the coatings especially suitable for application on temperature sensitive base materials.

A method comprising (a) contacting a suspension composition, water, and optionally one or more additives to form a wellbore servicing fluid at a location proximate a wellsite; wherein the suspension composition comprises a particulate material, an organic carrier fluid, and a suspension viscosifier; and (b) placing the wellbore servicing fluid in a wellbore penetrating a subterranean formation. The wellsite comprises an offshore platform, a floating vessel, or combinations thereof; and wherein the wellbore is offshore. A suspension composition comprising a particulate material, an organic carrier fluid, and a suspension viscosifier; wherein the particulate material is substantially insoluble in the organic carrier fluid; wherein the particulate material comprises a water-interactive material and/or a water-insoluble material; and wherein the organic carrier fluid comprises a glycol and/or a glycol ether.

A method comprising (a) contacting a suspension composition, water, and optionally one or more additives to form a wellbore servicing fluid at a location proximate a wellsite; wherein the suspension composition comprises a particulate material, an organic carrier fluid, and a suspension viscosifier; and (b) placing the wellbore servicing fluid in a wellbore penetrating a subterranean formation. The wellsite comprises an offshore platform, a floating vessel, or combinations thereof; and wherein the wellbore is offshore. A suspension composition comprising a particulate material, an organic carrier fluid, and a suspension viscosifier; wherein the particulate material is substantially insoluble in the organic carrier fluid; wherein the particulate material comprises a water-interactive material and/or a water-insoluble material; and wherein the organic carrier fluid comprises a glycol and/or a glycol ether.

A nano-silver dispersion and a preparation method thereof is disclosed. The method, includes: mixing γ-aminopropyltriethoxysilane, polyvinylpyrrolidone, sodium lauryl sulfate, silver nitrate and water, and conducting a chelation, to obtain a chelating dispersion, wherein before the mixing, the γ-aminopropyltriethoxysilane is exposed to the air for less than 5 min; and dropwise adding a sodium borohydride solution into the chelating dispersion, to obtain a mixture, and subjecting the mixture to an oxidation-reduction reaction, to obtain the nano-silver dispersion.

To provide a prestressed concrete which can be used for non-primary structural members such as general building members by using a chemical stress induced by an expansive material and a mechanical stress induced by a rust-resistant wire together and achieving reduction in weight and suppression of cracking. A prestressed concrete for non-primary structural members is characterized in that a mechanical stress induced by a tensional material and a chemical stress induced by an expansive material for a concrete are introduced and that the tensional material is a rust-resistant continuous fiber reinforcing wire.

To provide a prestressed concrete which can be used for non-primary structural members such as general building members by using a chemical stress induced by an expansive material and a mechanical stress induced by a rust-resistant wire together and achieving reduction in weight and suppression of cracking. A prestressed concrete for non-primary structural members is characterized in that a mechanical stress induced by a tensional material and a chemical stress induced by an expansive material for a concrete are introduced and that the tensional material is a rust-resistant continuous fiber reinforcing wire.