Abstract: Herein discloses a method of carbonating reactive magnesia cement, which includes: (i) providing an aqueous suspension including a carbon dioxide-producing bacteria; (ii) mixing the aqueous suspension with a precursor which the carbon dioxide-producing bacteria generates carbon dioxide from for a duration to form an aqueous mixture sufficient for substantially carbonating the reactive magnesia cement; (iii) mixing the aqueous mixture with the reactive magnesia cement to form a blend; wherein a nutrient is provided in the aqueous suspension of step (i) or in the reactive magnesia cement of step (iii) to sustain the carbon dioxide-producing bacteria in the reactive magnesia cement; and (iv) curing the blend to carbonate the reactive magnesia cement. A reactive magnesia cement composite formed by the method is also disclosed.

Abstract: There is provided a fiber-reinforced brittle matrix composite. The fiber-reinforced brittle matrix composite comprises a brittle matrix material (for example, a cementitious or ceramics material) and a coated fiber embedded in the brittle matrix material, wherein the coated fiber comprises a fiber (for example, polyethylene fiber, glass fiber, silicon carbide fiber, alumina fiber, mullite fiber) and a coating material (for example, carbon nanofibers, carbon nanotubes), which is non-covalently disposed on the fiber. A method for producing the fiber-reinforced brittle matrix composite is also provided. The method comprises providing a fiber, disposing a coating material on the fiber to form a coated fiber, wherein the coating material is non-covalently disposed on the fiber, and embedding the coated fiber in a brittle matrix material to obtain the fiber-reinforced brittle matrix composite.

Abstract: The present invention relates to a cementitous composite specifically engineered to possess self-cleaning abilities while maintaining their unique strain-hardening behaviour and the preparation of the said composite. The cementitious composite comprises a hydraulic cement, a plurality of fibers, in particular polyvinyl alcohol fibers wherein the ratio of the plurality of fibers to the hydraulic cement is in a range from 1 to 3% by volume; a self-cleaning agent, in particular nanoparticulate titanium dioxide (TiO2) wherein the weight ratio of the self-cleaning agent to the hydraulic cement is in a range from 0.01 to 1.

Abstract: Disclosed herein are phase change materials microencapsulated by a microcapsule having two shells, the first shell (directly encapsulating the phase change material) being an organic polymeric material and the second shell (an outer shell) being made from a doped TiO2 material. The microcapsules disclosed herein may be particularly useful for improving the energy efficiency of indoor environments, as well as providing compositions that they are applied to (e.g. paints) with self-cleaning properties.

Abstract: The present invention relates to a cementitous composite specifically engineered to possess self-cleaning abilities while maintaining their unique strain-hardening behaviour and the preparation of the said composite. The cementitious composite comprises a hydraulic cement, a plurality of fibers, in particular polyvinyl alcohol fibers wherein the ratio of the plurality of fibers to the hydraulic cement is in a range from 1 to 3% by volume; a self-cleaning agent, in particular nanoparticulate titanium dioxide (TiO2) wherein the weight ratio of the self-cleaning agent to the hydraulic cement is in a range from 0.01 to 1.

Abstract: Cementitious composites engineered for self-healing, combining self-controlled tight crack width and extreme tensile ductility. Self-healing takes place automatically at cracked locations without external intervention. In the exemplary embodiment, fiber-reinforced cementitious composites with self-controlled tight crack width less than 50 ?m and tensile ductility more than 2% are prepared. Self-healing in terms of mechanical and transport properties recovery of pre-damaged (by pre-cracking) composite is revealed in a variety of environmental exposures, include wetting and drying cycles, water permeation, and chloride submersion.

Abstract: An extremely ductile fiber reinforced brittle matrix composite is of great value to protective structures that may be subjected to dynamic and/or impact loading. Infrastructures such as homes, buildings, and bridges may experience such loads due to hurricane lifted objects, bombs, and other projectiles. Compared to normal concrete and fiber reinforced concrete, the invented composite has substantially improved tensile strain capacity with strain hardening behavior, several hundred times higher than that of conventional concrete and fiber reinforced concrete even when subjected to impact loading. The brittle matrix may be a hydraulic cement or an inorganic polymer. In an exemplary embodiment of the teachings, the composites are prepared by incorporating pozzolanic admixtures, lightweight filler, and fine aggregates in Engineered Cementitious Composite fresh mixture, to form the resulting mixtures, then placing the resulting mixtures into molds, and curing the resulting mixtures.

Abstract: Cementitious composites engineered for self-healing, combining self-controlled tight crack width and extreme tensile ductility. Self-healing takes place automatically at cracked locations without external intervention. In the exemplary embodiment, fiber-reinforced cementitious composites with self-controlled tight crack width less than 50 ?m and tensile ductility more than 2% are prepared. Self-healing in terms of mechanical and transport properties recovery of pre-damaged (by pre-cracking) composite is revealed in a variety of environmental exposures, include wetting and drying cycles, water permeation, and chloride submersion.