Abstract: A method for producing vapor grown carbon, including mixing a raw material gas containing an organic compound and an organo-transition metallic compound preliminarily heated preferably to a temperature of 100 to 450° C. with a carrier gas heated preferably to a temperature of 700 to 1,600° C., and introducing the resultant gas mixture into a carbon fiber production zone, wherein preferably a mixture of an aromatic compound and acetylene, ethylene, or butadiene is used as an organic compound. The method can include dissolving the transition metallic compound in a solvent, atomizing the resultant solution into fine droplets, evaporating the solvent in the droplets to thereby obtain fine particles of the transition metal compound, and introducing the drifting particles with an organic compound gas into the carbon fiber production zone. Vapor grown carbon fiber is thereby produced.

Abstract: A porous material comprising vapor grown carbon fiber in an amount of 10 to 90 mass %, fiber filaments of the carbon fiber forming a three-dimensional network and having a diameter of 1 to 1,000 nm, an aspect ratio of 5 to 15,000, a specific surface area (by BET method) of 2 to 2,000 m2/g, and the ratio of the intensity of the peak at 1,360 cm?1 in a Raman scattering spectrum of the carbon fiber to that of the peak at 1,580 cm?1 in the spectrum(I1360/I1580) is 0.1 to 2.0, wherein the porosity of the porous material (V/V0) is 0.50 to 0.99 and a specific surface area is 5 to 1,000 m2/g; and a production method and use thereof. The vapor grow carbon fiber impregnated in the porous material of the present invention does not contain aggregates and a three-dimensional network is formed between the fiber filaments, wherein length of each of the fiber filaments is maintained.

Abstract: The present invention relates to a method for producing a resin composition having a crystallized and orderly arranged structure. The method comprises kneading an amorphous thermoplastic resin with a resin crystallization promoter to form a mixture, wherein the resin crystallization promoter comprises vapor grown carbon fibers, each fiber filament of the carbon fibers having a diameter of 0.001 ?m to 5 ?m and an aspect ratio of 5 to 15,000, the fibers having undergone a graphitization at 1,500° C. or higher, and subsequently subjecting the mixture to annealing at a temperature of from 55° C. higher than the glass transition point of the resin to a temperature 75° C. higher than the glass transition point of the resin. The crystallization promoter and annealing provide a thermoplastic resin composition, which, when molded, exhibits improved strength and tribological characteristics.

Abstract: A fine carbon fiber having an outer diameter of about 1 to about 80 nm and an aspect ratio of 10 to 30,000, comprising a hollow center portion and a multi-layer sheath structure of a plurality of carbon layers, the layers forming annual rings, wherein the sheath-forming carbon layers form an incomplete sheath, i.e., the carbon layers are partially broken or disrupted in a longitudinal direction, and the outer diameter of the carbon fiber and/or the diameter of the hollow center portion are not uniform in a longitudinal direction. The carbon fiber is obtained by instantaneously reacting a carrier gas at a high temperature and an organic compound gas kept at a temperature below the decomposition temperature of the transition metal compound and has a conductivity equivalent to that of a conventional vapor phase method and is useful as a filler material in resins, rubbers, paints and the like.

Abstract: A vapor grown fine carbon fiber, each fiber filament of the carbon fiber comprising, in its interior, a hollow space extending along the fiber filament, and having a multi-layer structure, an outer diameter of 2 to 500 nm, and an aspect ratio of 1 to 100, wherein the fiber filament comprises a cut portion on its surface along the hollow space, a production method therefor, and electrically conductive material, a secondary battery and a gas occlusion material using the carbon fiber. The fine carbon fiber of the present invention is excellent in properties such as occlusion of gases such as hydrogen and methane, smoothness, electrical conductivity and thermal conductivity, and also excellent in dispersability, wettability and adhesion with a matrix such as resin.

Abstract: The invention relates to a vapor grown carbon fiber having a mean fiber diameter of 80 to 500 nm, an aspect ratio of 100 to 200 and preferably a bulk density of 0.02 g/cm3 or less, wherein filaments having a diameter within ±20% the mean fiber diameter occupies 65% (on a number basis) or more of the total. The production method involves thermal decomposition of a carbon source at 800 to 1,300° C. in the presence of, as a catalyst, a transition metal compound having a vapor pressure of 0.13 kPa (1 mmHg) or more at 150° C. and spraying of the carbon source and the transition metal compound in gas form toward the reactor inner wall to allow reaction to proceed. The vapor grown carbon fiber having a larger aspect ratio has excellent dispersibility, and when added in a resin, a smaller amount contributes to enhancement in electroconductivity and thermal conductivity, as compared with a case using conventional one.

Abstract: A method is provided for evaluating pellet-cladding interaction (PCI) in a nuclear core having a reactor protection system and a plurality of elongated fuel rods each having fuel surrounded by cladding with a gap therebetween. The method includes: selecting a number of core parameters to be analyzed; evaluating the selected parameters at a plurality of statepoints; generating a model of an operating space of the core based, at least in part, upon the statepoints; selecting a subset or loci of statepoints from the model wherein each of the statepoints of the loci of statepoints, when subjected to a predetermined transient, falls within the operational limits of the reactor protection system; and evaluating the loci of statepoints for PCI in response to the transient. In this manner, the potential for PCI can be accurately determined without requiring every statepoint for every fuel rod in the core to be individually analyzed.

Abstract: The invention provides a method of producing vapor grown carbon fiber by vapor-phase reaction conducted by supplying carbon source compounds and a catalyst or a catalyst precursor into a heating zone, wherein at least one of the carbon source compound and the catalyst or the catalyst precursor is solid at room temperature and the solid compound is supplied in gas form into the heating zone from a material supplier filled with the solid material alone at a constant amount. The production method according to the invention enables efficient and stable production of vapor phase carbon fiber even by using a high-volume production equipment.

Abstract: A porous material comprising vapor grown carbon fiber in an amount of 10 to 90 mass %, fiber filaments of the carbon fiber forming a three-dimensional network and having a diameter of 1 to 1,000 nm, an aspect ratio of 5 to 15,000, a specific surface area (by BET method) of 2 to 2,000 m2/g, and the ratio of the intensity of the peak at 1,360 cm?1 in a Raman scattering spectrum of the carbon fiber to that of the peak at 1,580 cm?1 in the spectrum(I1360/I1580) is 0.1 to 2.0, wherein the porosity of the porous material (V/V0) is 0.50 to 0.99 and a specific surface area is 5 to 1,000 m2/g; and a production method and use thereof. The vapor grow carbon fiber impregnated in the porous material of the present invention does not contain aggregates and a three-dimensional network is formed between the fiber filaments, wherein length of each of the fiber filaments is maintained.

Abstract: The present invention relates to a composite of vapor grown carbon fiber and inorganic fine particles comprising vapor grown carbon fiber, each fiber filament of the carbon fiber having a structure with hollow space extending along its axis, a diameter of 0.001 to 1 ?m and an aspect ratio of 5 to 15,000; and inorganic fine particles having a particle size of 0.0001 to 5 ?m, the particles being deposited onto the surface of the carbon fiber, wherein the ratio of the average diameter of the vapor grown carbon fiber to the average particle size of the inorganic fine particles is 1 0.01 to 1:5; the ratio by mass of the vapor grown carbon fiber to the inorganic fine particles is 1:0.005 to 1:50; and the carbon crystal structure of the carbon fiber is maintained and the surface characteristics are modified.

Abstract: The invention provides a production method of a conductive polymer, comprising a step of blending a polymer in a state of a melt viscosity of 600 Pa·s or less at a shear rate of 100 s?1 with a vapor grown carbon fiber in 1 to 15 mass at a mixing energy of 1,000 mJ/m3 or less, and a conductive polymer obtained thereby. Preferably, a vapor grown carbon fiber used has an outer fiber diameter of 80 to 500 nm, an aspect ratio of 40 to 1,000, a BET specific surface area of 4: to 30 m2/g, a do02 of 0.345 nm or less according to an X-ray diffraction method, and a ratio (Id/Ig) of 0.1 to 2 wherein Id and Ig each represent peak heights of a band ranging from 1,341 to 1,349 cm?1 and a band ranging from 1,570 to 1,578 cm?1 respectively, according to a Raman scattering spectrum. According to the invention, an excellent conductivity can be attained by compounding vapor grown carbon fiber in a smaller amount than in a conventional method.

Abstract: A composite cable 21 with a plug 22 attached thereto includes optical fibers, metal wires, a tensile strength fiber 21a, and an envelope 21b for enveloping them and the plug 22 includes a ferrule 210 of the plug for connecting the optical fiber, a cable clamp 221 and a Kevler holder 222 (first fixing mechanism) for fixing the tensile strength fiber 21a, and a gasket 223 (second fixing mechanism) for blocking a twist of the envelope 21b and further includes a joint mechanism (227) of a detachable traction cap for pulling the composite cable 21 and inserting the composite cable 21 into piping.

Abstract: A high-sensitivity measuring instrument comprising at least two sensors for detecting the same characteristics by touching a substance being measured with a specified time difference, wherein the between detection signals taken out simultaneously from respective sensors is determined, the difference between characteristic values upon elapsing the specified time difference is determined from the difference between detection signals, a reference time of measurement and a reference characteristic value at that time are preset, a time axis having a time pitch of a specified time difference is set, and a measurement value is obtained at a point in time elapsing an arbitrary time pitch from the reference time. Objective measurement characteristics can be detected by the measuring instrument not in the form of difference or variation but as an absolute value with high accuracy and sensitivity.

Abstract: An electrical insulating vapor grown carbon fiber containing a vapor grown carbon fiber having a fiber diameter of 0.01 to 0.5 ?m, wherein the surface thereof is partially or entirely coated with an electrical insulating material and a method of producing thereof is disclosed.

Abstract: An object of the present invention is to provide a method and apparatus for heat-treating carbon fiber, in which impairment of a furnace caused by solidification of a transition metal impurity serving as a catalyst raw material is prevented, and the amount of the metal, such as Fe, Co, or Ni, contained in the carbon fiber is reduced. In the present invention, a vaporized metal impurity is contained in an inert gas that is passed through a furnace, and the gas is discharged from a high-temperature section of the furnace. The impurity contained in the gas discharged from the furnace is cooled to solidify, and then recovered. The resultant gas is recycled as an inert gas in the furnace.

Abstract: The present invention relates to a thermoplastic resin crystallization promoter comprising fine carbon fiber consisting of fiber filaments having a diameter of 0.001 ?m to 5 ?m and an aspect ratio of 5 to 15,000, a thermoplastic resin composition consisting of the fine carbon fiber and thermoplastic resin and comprising crystallized resin, and a production method thereof. The crystallization promoter comprising the fine carbon fiber of the present invention enables to crystallize even an amorphous resin, which has an irregular molecular structure and therefore is not crystallized, or which exhibits low crystallization degree and therefore is difficult to crystallize by means of a conventional crystallization promoter. The crystallization promoter provides a thermoplastic resin composition, which, when molded, exhibits improved strength and tribological characteristics and is further reinforced when mixed with a filler.

Abstract: A branched vapor-grown carbon fiber having an outer diameter of 0.5 ?m or less and an aspect ratio of at least 10, the carbon fiber having a compressed specific resistance of 0.02 ?·cm or less, each fiber filament having a hollow cylindrical structure, preferably the carbon fiber containing boron and having a compressed specific resistance of 0.018 ?·cm or less. An electrically conductive transparent composition comprising a resin binder and carbon fiber incorporated into the binder, having transparency and comprising vapor grown carbon fiber having an outer diameter of 0.01–0.1 ?m, an aspect ratio of 10–15,000, and a compressed specific resistance of 0.02 ?·cm or less, and surface resistivity of 10,000 ?/? or less. An electrically conductive transparent material formed from the aforementioned electrically conductive transparent composition.

Abstract: A vapor-grown-carbon-fiber-containing dispersion containing vapor grown carbon fiber having a fiber diameter of and an aspect ration of 5 to 15,000, a resin soluble in an organic solvent, and an organic solvent having an ET value of 45 or less, which value is a solvent parameter calculated from the absorption spectrum of pyridinium-N-phenol betaine, wherein (1) lumps of the carbon fiber are partially disintegrated to thereby allow individual filaments of the carbon fiber to be present as dispersed or (2) the carbon fiber is present such that carbon fiber lumps having a diameter of 40 ?m or less and separated individual carbon fiber filaments are intermingled; a production method of the dispersion; vapor-grown-carbon-fiber-containing resin composite material obtained by the method; and electroconductive material and thermal conductive material using the resin composite material.

Abstract: A fine carbon fiber having an outer diameter of about 1 to about 80 nm and an aspect ratio of 10 to 30,000, comprising a hollow center portion and a multi-layer sheath structure of a plurality of carbon layers, the layers forming annual rings, wherein the sheath-forming carbon layers form an incomplete sheath, i.e., the carbon layers are partially broken or disrupted in a longitudinal direction, and the outer diameter of the carbon fiber and/or the diameter of the hollow center portion are not uniform in a longitudinal direction. The carbon fiber is obtained by instantaneously reacting a carrier gas at a high temperature and an organic compound gas kept at a temperature below the decomposition temperature of the transition metal compound and has a conductivity equivalent to that of a conventional vapor phase method and is useful as a filler material in resins, rubbers, paints and the like.

Abstract: (1) A carbonaceous material for forming an electrically conductive composition, comprising a vapor grown carbon fiber, each fiber filament of the carbon fiber having an outer diameter of 2 to 500 nm and an aspect ratio of 10 to 15,000, or the carbon fiber containing boron in an amount of 0.01 to 5 mass %, and graphitic particles and/or amorphous carbon particles, wherein the amount of the vapor grown carbon fiber is 10 to 90 mass %, the amount of the graphitic particles is 0 to 65 mass %, and the amount of the amorphous carbon particles is 0 to 35 mass %; (2) an electrically conductive composition comprising the carbonaceous material for forming an electrically conductive composition, and a producing method thereof; (3) an electrically conductive coating material comprising, as an electrically conductive material, the electrically conductive composition, and an electrically conductive coating film and electric device using the electrically conductive coating material.