An aqueous dispersion of graphene oxide is prepared in an additive process by subjecting graphitic carbon, such as biochar, in water or an aqueous solution to a high-shear environment in the presence of a dispersing agent to exfoliate graphene oxide. An intercalating agent may be added to facilitate exfoliation, and optionally neutralized. The graphitic carbon may be pre-processed by wet milling prior to exfoliation. The aqueous dispersion of graphene oxide may be used as a concrete admixture in a concrete composition.

Provided herein are systems for carbonation curing and CO.sub.2 mineralization of concrete composites and methods of manufacturing a carbonated concrete composite. A method of manufacturing a carbonated concrete composites includes contacting concrete with CO.sub.2-containing gas streams in the carbonation reactor having a gas stream inlet and an outlet to provide optimal gas flow distribution and gas velocity. The concrete precursor includes a binder, one or more aggregates, and water. A gas stream is received at the carbonation reactor. The gas stream includes carbon dioxide. The concrete precursor is maintained at a suitable temperature in the carbonation reactor to thereby react the concrete precursor with the gas stream to produce carbonate minerals in the carbonated concrete composite.

This invention relates to a solidifying agent for solidifying radioactive waste, and more particularly to a solidifying-agent composition for solidifying radioactive waste, including alumina cement and a gypsum powder. The solidifying-agent composition including alumina cement and a gypsum powder is capable of effectively minimizing an increase in the volume of a solidified radioactive waste product to a level satisfying physical and chemical safety regulations upon the solidification of radioactive waste.

A method of designing a cement slurry may include: providing a cement slurry recipe comprising water and at least one cementitious component; creating a model of a compressive strength of the cement recipe for a given time; preparing a cement slurry based at least in part on the model; and introducing the cement slurry into a subterranean formation.

A concrete composition that includes (i) a treated palm oil fuel ash, wherein the treated palm oil fuel ash is the only binder present, (ii) a fine aggregate, (iii) a coarse aggregate, and (iv) an alkali activator containing an aqueous solution of sodium hydroxide and sodium silicate. A cured concrete made from the concrete composition is also disclosed with advantageous compressive strength properties.

The invention relates to processes for making improved ultra-high performance concrete with plasma-treated inclusions and articles made from the same. The invention includes a process for producing silicon carbide and multiwalled carbon nanotubes by heating agricultural waste husks in an inert atmosphere to a temperature higher than 1300 degrees C. to obtain a mixture containing silicon carbide and MWCNTs, and treating the mixture to extract the silicon carbide and MWCNTs for use as microinclusions in ultra high performance concrete.

A ceramic material includes zirconia toughened alumina (ZTA), which is doped with zinc ions and other metal ions, in which the other metal ions are chromium (Cr) ions, titanium (Ti) ions, gadolinium (Gd) ions, manganese (Mn) ions, cobalt (Co) ions, iron (Fe) ions, or a combination thereof. The ceramic material may have a hardness of 1600 Hv10 to 2200 Hv10 and a bending strength of 600 MPa to 645 MPa. The ceramic material can be used as wire bonding capillary.

Systems and methods of sequestering carbon dioxide in concrete are described herein. The methods include combining water and a foaming agent to form a foaming agent mixture, adding a gas comprising carbon dioxide to the foaming agent mixture in a first mixing chamber, mixing the water, the gas comprising carbon dioxide and the foaming agent to form a foam mixture in the first mixing chamber, the foam mixture comprising a plurality of foam bubbles containing the at least a portion of the carbon dioxide, combining the foam mixture with concrete materials in a second mixing chamber so that the foam mixture contacts the concrete materials, the concrete materials comprising cement, and mixing the foam mixture and the concrete materials in the second mixing chamber to form the concrete having the carbon dioxide sequestered therein.

The present invention provides a fiber-reinforced cement composition comprising; cement, fiber, silica, filler, expanded perlite, and polymer. The fiber-reinforced cement composition according to the present invention has low density, high toughness and flexural strength, and not contains volatile composition. When it is molded into workpiece, the workpiece is lightweight, easy to be cut and/or lathed into desired shapes, drilled and fixed with screws and/or repeatedly nailed at the same position, tolerant to humidity, termites and insects, inflammable and does not produce powder when cut, drilled and/or lathed that is hazardous to the workers. Therefore, it is suitably applicable for being utilized as a material for manufacturing furniture parts.

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.