Abstract: Methods and processes for synthesizing high quality carbon single-walled nanotubes (SWNTs) are provided. A carbon precursor gas is contacted with a catalyst deposited on a support. The temperature and the duration of the reaction are varied to produce SWNTs with the ratio of G-band to D-band in Raman spectra (IG:ID) of about 5 to about 70.

Abstract: Carbon nanotubes are formed by chemical vapor deposition using metal nanoparticles as a growth substrate. Control over the size and properties of the carbon nanotubes is achieved by controlling the size of the metal nanoparticles in the growth substrate. The metal nanoparticles of a controlled size may be formed by a thermal decomposition reaction of a metal salt in a passivating solvent.

Abstract: A method for treating carbon nanotubes with microwave energy to selective remove metallic-type carbon nanotubes is provided. A sample containing carbon nanotubes is positioned in a microwave cavity at a location corresponding to a maximum in the electric field component of a stationary wave having a microwave frequency. The sample is exposed to the microwave energy for a sufficient period of time to increase the proportion of semiconducting-type carbon nanotubes within the sample. Alternatively, a sample consisting essentially of metallic-type and semiconducting-type carbon nanotubes is exposed to microwave energy for a sufficient period of time to increase the proportion of semiconducting-type carbon nanotubes within the sample.

Abstract: The present teachings are directed toward composite materials containing nanotubes and an electrically conductive polymer, poly(3,4-ethylenedioxythiopene), and devices, such as capacitors, containing the composite materials.

Abstract: A method for treating carbon nanotubes with microwave energy to selective remove metallic-type carbon nanotubes is provided. A sample containing carbon nanotubes is positioned in a microwave cavity at a location corresponding to a maximum in the electric field component of a stationary wave having a microwave frequency. The sample is exposed to the microwave energy for a sufficient period of time to increase the proportion of semiconducting-type carbon nanotubes within the sample. Alternatively, a sample consisting essentially of metallic-type and semiconducting-type carbon nanotubes is exposed to microwave energy for a sufficient period of time to increase the proportion of semiconducting-type carbon nanotubes within the sample.

Abstract: Methods and processes for synthesizing single-wall carbon nanotubes are provided. A carbon precursor gas is contacted with metal catalysts deposited on a support material. The metal catalysts are preferably nanoparticles having diameters less than about 3 nm. The reaction temperature is selected such that it is near the eutectic point of the mixture of metal catalyst particles and carbon. Further, the rate at which hydrocarbons are fed into the reactor is equivalent to the rate of formation of carbon SWNTs for given synthesis temperature. The methods produce carbon single-walled nanotubes having longer lengths.

Abstract: Methods and processes for quantitating the carbon single-walled nanotubes (SWNTs) content in a sample are disclosed. The SWNTs soot can be produced by any of the known methods. The magic angle spinning (MAS) 13C NMR of a sample suspected of containing SWNTs and a standard at a known concentration are obtained, and the areas under the curve for the sample and the standard are calculated. Thereby, the concentration of 13C atoms involved in the formation of carbon SWNTs are calculated. Finally, by taking into account the natural distribution of 13C isotopes (about 1.1%), the total concentration of all carbon atoms responsible for the formation of SWNTs are calculated.

Abstract: The present teachings are directed toward methods for preparing activated capacitor materials by exposing capacitor material to an electrical potential of sufficient voltage and for a sufficient time to activate the capacitor materials. Compositions of capacitor materials containing carbon nanotubes and other carbon-containing materials are also disclosed.

Abstract: Methods and processes for determining the particle size distribution of metal catalysts are provides. Superconducting Quantum Interference Device (SQUID) magnetometer is used to evaluate the magnetic catalyst particle sizes dispersed in the support material. Dependence on variation of the metal/support material ratio, which defines the metal particle sizes, the catalyst can show paramagnetic, superparamagnetic, and ferromagnetic behaviors.

Abstract: Methods and processes for preparing supported metal catalysts are provided, where the supported metal catalysts can be used for the bulk synthesis of carbon nanotubes. The salts of the metal and the support are selected such that they are soluble in the same solvent. The catalyst can be prepared from the liquid phase through joint precipitation of the metal and the support material. The methods can be used to increase the metal load on the support. Use of the catalysts increases the yield of the carbon nanotubes.

Abstract: Method and processes for synthesizing single-wall carbon nanotubes is provided. A carbon precursor gas is contacted with metal deposited on a support material. The metal catalysts are preferably nanoparticles having diameters less than about 50 nm. The reaction temperature is selected such that it is near the eutectic point of the mixture of metal catalyst particles and carbon.

Abstract: Metal nanoparticles are formed by heating or refluxing a mixture of a metal salt, such as a metal acetate, and a passivating solvent, such as a glycol ether, at a temperature above the melting point of the metal salt for an effective amount of time.

Abstract: Metal nanoparticles containing two or more metals are formed by heating or refluxing a mixture of two or more metal salts, such as a metal acetates, and a passivating solvent, such as a glycol ether, at a temperature above the melting point of the metal salts for an effective amount of time.

Abstract: A method for treating carbon nanotubes with microwave energy to selective remove metallic-type carbon nanotubes is provided. A sample containing carbon nanotubes is positioned in a microwave cavity at a location corresponding to a maximum in the electric field component of a stationary wave having a microwave frequency. The sample is exposed to the microwave energy for a sufficient period of time to increase the proportion of semiconducting-type carbon nanotubes within the sample. Alternatively, a sample consisting essentially of metallic-type and semiconducting-type carbon nanotubes is exposed to microwave energy for a sufficient period of time to increase the proportion of semiconducting-type carbon nanotubes within the sample.

Abstract: Metal nanoparticles are formed by heating or refluxing a mixture of a metal salt, such as a metal acetate, and a passivating solvent, such as a glycol ether, at a temperature above the melting point of the metal salt for an effective amount of time.

Abstract: Metal nanoparticles containing two or more metals are formed by heating or refluxing a mixture of two or more metal salts, such as a metal acetates, and a passivating solvent, such as a glycol ether, at a temperature above the melting point of the metal salts for an effective amount of time.

Abstract: Carbon nanotubes are formed by chemical vapor deposition using metal nanoparticles as a growth substrate. Control over the size and properties of the carbon nanotubes is achieved by controlling the size of the metal nanoparticles in the growth substrate. The metal nanoparticles of a controlled size may be formed by a thermal decomposition reaction of a metal salt in a passivating solvent.

Abstract: A hydrogen-storage material includes a plurality of carbon carriers made of a carbon material having an electric conductivity, and a plurality of fine particles carried on each of the carbon carriers and having a hydrogen-adsorbing ability. The amount A of fine particles carried is in a range of 0.1% by weight≦A≦20% by weight. The fine particles are at least one selected from fine particles of a metal, fine particles of an alloy and fine particles of an oxide semiconductor. For example, the alloy corresponds to an alloy made of at least one selected from the group consisting of Mg, Ti, a rare earth element, Zr, V, Ca and Al, and at least one selected from the group consisting of Fe, Co, Ni, Cu, Mn, Mo and W. Thus, the hydrogen-storage material is relatively light; has a high hydrogen-storing ability at ambient temperature and under a lower hydrogen pressure; and moreover, exhibits hydrogen-absorbing/releasing rates.

Abstract: There is provided a method of manufacturing a carbon nanotube so as to be able to increase the yield of a web and to increase the amount of a carbon nanotube contained in the web. A high-energy heat source is caused to act on carbon in the presence of catalysts. The catalysts include a main catalyst made of at least one metal which is selected from the group consisting of an iron group element, a platinum group element, and a rare earth element, and an auxiliary catalyst made of a material which causes an exothermic reaction in a process of generating the web including the carbon nanotube. The auxiliary catalyst is made of a material for generating a carbide more stable in terms of thermal energy than a carbide generated by the main catalyst. The free formation energy of the carbide generated from the material is smaller than the free formation energy of the carbide generated by the main catalyst.

Abstract: A clutch disk made of a C/C composite for a wet multi-plate clutch is comprised of a disk body, and a pair of friction layers integral with and on opposite sides of the disk body for sliding contact with clutch plates. A relationship of V.sub.2 >V.sub.1 is established between the porosity V.sub.1 of the disk body and the porosity V.sub.2 of the friction layer, and the porosity V.sub.2 of the friction layer 4 is set in a range of 20%.ltoreq.V.sub.2 .ltoreq.60%, which provides a clutch disk with sufficient strength and excellent sliding characteristics.