Cementing compositions containing a hydraulic cement, halloysite nanoparticles, and silica flour. The cementing compositions may optionally include other additives such as a friction reducer, a defoamer, and a fluid loss additive. Cement samples made therefrom and methods of producing such cement samples are also specified. The addition of halloysite nanoparticles and silica flour provides enhanced mechanical strength (e.g. compressive strength, flexural strength) and improved durability (e.g. resistance to CO.sub.2 and salinity) to the cement, making them suitable cementing material for oil and gas wells.

The disclosure relates to a method of delaying viscosification of a well treatment fluid within a well or within a subterranean formation penetrated by a well by introducing into the well a hydratable viscosifying agent of particulates having a minimum of 40% retention on a 60 mesh screen and a minimum of 1% retention on a 20 mesh screen.

The disclosure relates to a method of delaying viscosification of a well treatment fluid within a well or within a subterranean formation penetrated by a well by introducing into the well a hydratable viscosifying agent of particulates having a minimum of 40% retention on a 60 mesh screen and a minimum of 1% retention on a 20 mesh screen.

A method for manufacturing an engineered stone, the method including: providing a mixture comprising at least a stone or stone like material and a binder; compacting the mixture; curing the binder; and further comprising printing a printed pattern on at least a top surface of the engineered stone.

A method for manufacturing an engineered stone, the method including: providing a mixture comprising at least a stone or stone like material and a binder; compacting the mixture; curing the binder; and further comprising printing a printed pattern on at least a top surface of the engineered stone.

A method for producing photocatalytic mortar includes providing a mortar-producing material including a fine aggregate and cement, a reactant mixture including a zinc source and urea, and a microorganism-containing mixture including water and a urease-producing microorganism, subjecting the microorganism-containing mixture and the reactant mixture to microbial induced precipitation in the mortar-producing material, subjecting zinc carbonate crystal-containing mortar produced to curing for the same to undergo hydration, and subjecting cured mortar to hydrothermal synthesis, so that zinc carbonate crystals therein are converted to nano zinc oxide crystals.

A method for producing photocatalytic mortar includes providing a mortar-producing material including a fine aggregate and cement, a reactant mixture including a zinc source and urea, and a microorganism-containing mixture including water and a urease-producing microorganism, subjecting the microorganism-containing mixture and the reactant mixture to microbial induced precipitation in the mortar-producing material, subjecting zinc carbonate crystal-containing mortar produced to curing for the same to undergo hydration, and subjecting cured mortar to hydrothermal synthesis, so that zinc carbonate crystals therein are converted to nano zinc oxide crystals.

A concrete and asphalt repair coating formulation includes a cement component and an aggregate component. The cement component includes a calcium sulfoaluminate cement and a Portland cement. The aggregate component includes coarse aggregates between 125-500 microns in diameter and fine aggregates between 5-62.5 microns in diameter.

A concrete and asphalt repair coating formulation includes a cement component and an aggregate component. The cement component includes a calcium sulfoaluminate cement and a Portland cement. The aggregate component includes coarse aggregates between 125-500 microns in diameter and fine aggregates between 5-62.5 microns in diameter.

The invention comprises a cementitious material comprising a natural pozzolan selected from hyaloclastite, sideromelane or tachylite, wherein the natural pozzolan has a volume-based mean particle size of less than or equal to 40 μm. The cementitious material also comprising an aqueous alkaline activating solution suitable for forming a geopolymer. A method making a cementitious material is also disclosed.