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The use of carbon nanotubes, fullerenes and fullerene-like cages in electronic applications is limited because of the practical difficulties in creating electrode contacts to them. This is because such carbon nanoparticles are produced in powder form or as aligned carbon nanotubes (individual or in bundles). The latter might soon be grown at pre-defined positions and across metal electrodes in electronic...
The magneto-optical Kerr effect of single-walled carbon nanotubes (SWNTs) film in the Terahertz region is theoretically studied by means of the Drude model. The calculation shows a new oscillation occurring near the plasma frequency as the origin of the magneto-optical Kerr effect for the single-walled nanotubes film. We propose that the amplitude of this near plasma frequency oscillation is directly...
The effect of porous carbon preform and the infiltration process on the properties of reaction-formed SiC have been investigated in this paper. Five different porous carbon preforms with porosity in a range 35-67% and pore size from 0.03 to 2.58 μm have been infiltrated with liquid or vapor Si. The porous carbon preform and infiltration process affect the reaction rate and infiltration rate, which...
The effect of argon ion irradiation on the field emission (FE) and luminescent properties of screen-printed carbon nanotubes (SP-CNTs) with square pixels was examined, to further improve field emission displays (FEDs) applications. Persistent problems associated with SP-CNTs such as bent or/and buried CNTs and the degradation of binder-residue-induced emission were improved as a result of the permanent...
The fatigue of C/C composites was investigated in bending and shear modes. In bending, a large stress ratio resulted in a decrease in strength; the decrease became small without water present. However, a large ratio led to a decrease in Young's modulus, regardless of the presence of water. In shear, degradation in strength or fatigue life decreased with increasing the ratio. For specimens fatigue...
A kinetic study is presented for the synthesis of multi-walled carbon nanotubes in a semi-continuous chemical vapor deposition reactor. The study is based on the use of a mass spectrometer that allows the reaction rate to be inferred from the exhaust gas composition measurements. The tested reactor operating variables are the length and thickness of the catalytic bed, the total feed flow and the molar...
The utilization of carbon nanotubes (CNTs) as building blocks for nanodevices can only be realized when their electronic properties are preserved in the device configuration. It has been shown that bending and overlapping of CNTs result in a decrease in their conductance. Heterojunctions of quantum dots (QDs) and multiwalled carbon nanotubes (MWCNTs) could become better alternatives for the synthesis...
Recently developed two lattice density functional theory (DFT) models are verified experimentally. For this purpose the experimental nitrogen isotherms on carbon blacks at 77 K (M4040 and M32B) were carefully measured by the volumetric apparatus. Moreover, the additional nitrogen data on Sterling FT and SAO carbon blacks were taken from the literature and analyzed. The main goal of this study is the...
The solubility of C 60 Fullerene has been correlated with Hansen solubility parameters (HSP) in a database of 89 organic solvents. The parameters δ D , δ P , and δ H for C 60 were determined as 19.7, 2.9, and 2.7, respectively, with units MPa 1/2 . These parameters are indicative of an essentially nonpolar solid, and have been used...
A simple technique has been realized for characterizing the degree of carbon nanotube dispersion in polymer matrices based on the AC impedance spectra, which reveals the nature of circuit elements in the composites, i.e. film resistance and capacitance. A model is proposed to account for nanotube migration in the polymer matrix.
To elucidate the mechanism of the stabilization of pitches by iodine vapor below the melting temperatures of the pitches, the sorption or effect of introducing iodine into pitches and model-compounds was investigated using iodine sorption, Raman spectroscopy, 127 I Mossbauer spectroscopy and gel permeation chromatography. Introduced/sorbed iodine was, at least, in two forms in the...
A nonaqueous electrolyte solution is employed to form double layers on a poly(vinylidene chloride) (PVDC)-based carbon material, thereby extending the application of PVDC-based carbon to nonaqueous systems. Thermal behavior of the Npv-series, which was obtained by simple heat treatment under an inert atmosphere, and the Apv-series, which is obtained by potassium hydroxide (KOH) addition, is confirmed...
Composites of ultra-high molecular weight polyethylene (UHMWPE), low molecular weight polyethylene (LMWPE) and carbon fibers (CF) were prepared by gelation/crystallization from solution. The maximum intensity of PTC (positive temperature coefficient), the magnitude being ca. 9 orders, was found for a LMWPE/UHMWPE composition of 9/1 containing 23.5 vol% CF, i.e. a much higher amount of the filler than...
Reaction-induced phase separation occurred in the curing process of miscible blends of phenolic resin and poly(methyl methacrylate) (PMMA), and, a co-continuous nanostructure composed of phenolic resin rich phase and PMMA rich phase was obtained. The cured phenolic resin having continuous nanopores was obtained by extraction of PMMA. The sample was thermally treated to obtain a carbonaceous material...
UV-visible spectroscopy provides an extremely powerful methodology to investigate molecular structures of high molecular weight aromatic materials, not amenable to be characterized by analytical techniques as gas-chromatography, mass spectrometry, etc. However, the interpretation of UV-visible spectroscopic data relative to complex mixtures is extremely difficult and, when the technique is applied...
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