The present invention provides a graphite sheet having a ratio of thermal diffusivity in horizontal and vertical directions of 300 or more. Also, the present invention provides a graphite sheet having a ratio of thermal diffusivity in a vertical direction of 2.0 mm.sup.2/s or less. The graphite sheet has excellent thermal conductivity in horizontal and vertical directions and excellent flexibility at the same time and can be produced at low manufacturing cost, thereby holding an economic advantage.

The present invention provides a graphite sheet having a ratio of thermal diffusivity in horizontal and vertical directions of 300 or more. Also, the present invention provides a graphite sheet having a ratio of thermal diffusivity in a vertical direction of 2.0 mm.sup.2/s or less. The graphite sheet has excellent thermal conductivity in horizontal and vertical directions and excellent flexibility at the same time and can be produced at low manufacturing cost, thereby holding an economic advantage.

The present invention relates to a non-platinum catalyst for an oxygen reduction electrode, in which iron nanoparticles are dispersed in nitrogen-doped mesoporous carbon nanofibers, and the surfaces of the iron nanoparticles are at least partially exposed to the outside. In addition, the present invention relates to a method for producing a non-platinum catalyst for an oxygen reduction electrode using electrospinning and hydrogen activation reactions.

The present invention relates to a non-platinum catalyst for an oxygen reduction electrode, in which iron nanoparticles are dispersed in nitrogen-doped mesoporous carbon nanofibers, and the surfaces of the iron nanoparticles are at least partially exposed to the outside. In addition, the present invention relates to a method for producing a non-platinum catalyst for an oxygen reduction electrode using electrospinning and hydrogen activation reactions.

In order to provide a method for preparing a chalcogenide-carbon nanofiber, capable of implementing oxidation resistance characteristics and process simplification, the present invention provides a method for preparing a chalcogenide-carbon nanofiber and a chalcogenide-carbon nanofiber implemented by using the same, the method comprising the steps of: forming a chalcogenide precursor-organic nanofiber comprising a chalcogenide precursor and an organic material; and forming a chalcogenide-carbon nanofiber by selectively and oxidatively heat treating the chalcogenide precursor-organic nanofiber such that the carbon of the organic material is oxidized and the chalcogenide is reduced at the same time, wherein the oxidation reactivity of the chalcogenide is lower than that of carbon, the selective and oxidative heat treatment is carried out through one heat treatment step instead of a plurality of heat treatment steps, and the chalcogenide can form a chalcogenide-carbon nanofiber having a structure formed with at least one layer according to an oxygen partial pressure at which the selective and oxidative heat treatment is carried out.

In order to provide a method for preparing a chalcogenide-carbon nanofiber, capable of implementing oxidation resistance characteristics and process simplification, the present invention provides a method for preparing a chalcogenide-carbon nanofiber and a chalcogenide-carbon nanofiber implemented by using the same, the method comprising the steps of: forming a chalcogenide precursor-organic nanofiber comprising a chalcogenide precursor and an organic material; and forming a chalcogenide-carbon nanofiber by selectively and oxidatively heat treating the chalcogenide precursor-organic nanofiber such that the carbon of the organic material is oxidized and the chalcogenide is reduced at the same time, wherein the oxidation reactivity of the chalcogenide is lower than that of carbon, the selective and oxidative heat treatment is carried out through one heat treatment step instead of a plurality of heat treatment steps, and the chalcogenide can form a chalcogenide-carbon nanofiber having a structure formed with at least one layer according to an oxygen partial pressure at which the selective and oxidative heat treatment is carried out.

A composite comprising electrospun inorganic fibers and nanoparticles. The composite may carry a reagent, for example an oxidant. The composite may be formed by electro spinning a composition of a precursor material and nanoparticles to form a precursor composite followed by conversion of precursor fibers of the precursor composite to the inorganic fibers. The composite carrying a reagent may be used to absorb ethylene gas.

A composite comprising electrospun inorganic fibers and nanoparticles. The composite may carry a reagent, for example an oxidant. The composite may be formed by electro spinning a composition of a precursor material and nanoparticles to form a precursor composite followed by conversion of precursor fibers of the precursor composite to the inorganic fibers. The composite carrying a reagent may be used to absorb ethylene gas.

A method of separating carbon fiber tows. The method includes separating two or more first carbon fiber tows from a first tow band onto a second elevation to form two or more second carbon fiber tows from a second tow band. The two or more second carbon fiber tows from the second tow band leave gaps next to first adjacent tows of the two or more first carbon fiber tows remaining from the first tow band after the separating step. The first adjacent tows from the first tow band leave gaps next to second adjacent tows of the two or more second carbon fiber tows from the second tow band.

A method of separating carbon fiber tows. The method includes separating two or more first carbon fiber tows from a first tow band onto a second elevation to form two or more second carbon fiber tows from a second tow band. The two or more second carbon fiber tows from the second tow band leave gaps next to first adjacent tows of the two or more first carbon fiber tows remaining from the first tow band after the separating step. The first adjacent tows from the first tow band leave gaps next to second adjacent tows of the two or more second carbon fiber tows from the second tow band.