The disclosure provides for methods of oxidizing carbide anions, or negative ions, from salt like carbides at temperatures from about 150 C. to about 750 C. In another aspect, the disclosure provides for reactions with intermediate transition metal carbides. In yet another aspect, the disclosure provides for a system of reactions where salt-like carbide anions and intermediate carbide anions are oxidized to produce pure carbon of various allotropes.

Modified activated carbon is disclosed for use in water treatment. In at least some embodiments, activated carbon may be treated with a positively-charged surfactant, i.e. a quaternary ammonium-based surfactant, to promote the removal of poly- and perfluoroalkyl substances from water.

Modified activated carbon is disclosed for use in water treatment. In at least some embodiments, activated carbon may be treated with a positively-charged surfactant, i.e. a quaternary ammonium-based surfactant, to promote the removal of poly- and perfluoroalkyl substances from water.

A process of producing a yarn, ribbon or sheet that includes nanofibers in which the process includes forming a yarn, ribbon or sheet comprising nanofibers, and applying an enhancing agent comprising a polymer to the yarn, ribbon or sheet.

Fabricating a nanofiber sheet, ribbon, or yarn by a continuous process that includes synthesizing a nanofiber forest in a forest growth region on a substrate, wherein the nanofiber forest comprises a parallel array of nanofibers, and further includes drawing said nanofibers from the nanofiber forest to form a primary assembly that is a sheet, ribbon or yarn. The substrate continuously moves from the furnace growth region into a region where the nanofibers in the forest are drawn.

The present invention is directed to nanofiber yarns, ribbons, and sheets; to methods of making said yarns, ribbons, and sheets; and to applications of said yarns, ribbons, and sheets. In some embodiments, the nanotube yarns, ribbons, and sheets comprise carbon nanotubes. Particularly, such carbon nanotube yarns of the present invention provide unique properties and property combinations such as extreme toughness, resistance to failure at knots, high electrical and thermal conductivities, high absorption of energy that occurs reversibly, up to 13% strain-to-failure compared with the few percent strain-to-failure of other fibers with similar toughness, very high resistance to creep, retention of strength even when heated in air at 450 C. for one hour, and very high radiation and UV resistance, even when irradiated in air. Furthermore these nanotube yarns can be spun as one micron diameter yarns and plied at will to make two-fold, four-fold, and higher fold yarns. Additional embodiments provide for the spinning of nanofiber sheets having arbitrarily large widths. In still additional embodiments, the present invention is directed to applications and devices that utilize and/or comprise the nanofiber yarns, ribbons, and sheets of the present invention.

A nanofiber forest on a substrate can be patterned to produce a patterned assembly of nanofibers that can be drawn to form nanofiber sheets, ribbons, or yarns.

A nanofiber forest on a substrate can be patterned to produce a patterned assembly of nanofibers that can be drawn to form nanofiber sheets, ribbons, or yarns.

A nanofiber forest on a substrate can be patterned to produce a patterned assembly of nanofibers that can be drawn to form nanofiber sheets, ribbons, or yarns.

The disclosure provides for methods of oxidizing carbide anions, or negative ions, from salt like carbides at low temperatures below about 600 C. In another aspect, the disclosure provides for reactions with intermediate transition metal carbides. In yet another aspect, the disclosure provides for a system of reactions where salt-like carbide anions and intermediate carbide anions are oxidized to produce pure carbon of various allotropes.