Unusual physical properties of single-wall carbon nanotubes have started a search for similar tubular structures of other elements. In this paper, we present a theoretical analysis of single-wall nanotubes of silicon and group-III-V compounds. Starting from precursor graphenelike structures we investigated the stability, energetics, and electronic structure of zigzag and armchair tubes using th...

Single walled carbon nanotubes represent the future of structural aerospace vehicle systems due to their unparalleled strength characteristics and demonstrated multifunctionality. This multifunctionality rises from the CNT’s unique capabilities for both metallic and semiconducting electron transport, electron spin polarizability, and band gap modulation under strain. By incorporating the use of...

Internal functionalization of single-walled nanotubes is an attractive, yet difficult challenge in nanotube materials chemistry. Here we report single-walled metal oxide nanotubes with covalently bonded primary amine moieties on their inner wall, synthesized through a one-step approach. Conclusive molecular-level structural information on the amine-functionalized nanotubes is obtained through m...

Today’s business environment is causing utilities to examine methods to cut costs and to maximize revenues. Development of a comprehensive program for marketing and utilization* of coal combustion by-products (CCBPs) by a utility can generate additional revenue streams; reduce operating costs at plants; and defer capital costs of developing new waste disposal capacity. These factors can be opti...

carbon nanotube, a new structure of carbon element, is composed of graphene sheets rolled into closed concentric cylinders with diameter of the order of nanometers and length of micrometers. liquid arc discharge was used for fabrication of carbon nanotubes, and subsequently a modified acid treatment method applied for purification stage. a statistical design of experimental (doe) (taguchi metho...

Density-functional theory is used to investigate hydrogen physisorption on a graphene layer and on single wall carbon nanotubes. Both external and internal adsorption sites of 9, 0 and 10, 0 carbon nanotubes have been studied with the hydrogen molecular axis oriented parallel or perpendicular to the nanotube wall. A range of hydrogen molecule binding sites has been examined and it is found that...

Thin films of SWCNTs were prepared from toluene suspension of single wall carbon nanotubes. The material was dropped on silicon and platinum surfaces with a controlled thickness. Filling with C60 and DWCNT – transformation of the films was performed. Multifrequency Raman spectroscopy was used to follow the peapod formation process and double wall transformation of the tubes. An efficient fillin...

The effects of carbon nanotubes on the mechanical behavior of elastomeric materials is investigated. The large deformation uniaxial tension and uniaxial compression stress-strain behaviors of a representative elastomer are first presented. This elastomer is then reinforced with multi-wall carbon nanotubes (MWNTs) and the influence of weight fraction of MWNTs on the large deformation behavior of...

in order to evaluate the adsorption potential of multi-walled carbon nanotubes (mwcnts) for benzene, toluene and xylenes (btx), the adsorption capacities of benzene and toluene on two different mwcnts were measured using a gas-chromatography (gc) and then compared with each other. fourier transform infrared (ftir) was employed to investigate the presence of functional groups on the carbon nanot...

Magnetic susceptibility χ of pristine and brominated arc-produced sample of multi-wall carbon nanotubes was measured from 4.2 to 400 K. An additional contribution ∆χ(T) to diamagnetic susceptibility χ(T) of carbon nanotubes was found at T < 50 K for both samples. It is shown that ∆χ(T) are dominated by quantum correction to χ for interaction electrons (interaction effects-IE). The IE shows a cr...