Carbon nanotube length

Bettinger, H. F. (2004). Effects of finite carbon nanotube length on sidewall addition of fluorine atom and methylene. Organic Letters, 6,731-734. 

Fig. 26. High-resolution TEM images of bent and twisted carbon nanotubes. The length scales for these images are indicated [199].

In discussing the symmetry of the carbon nanotubes, it is assumed that the tubule length is much larger than its diameter, so that the tubule caps can be neglected when discussing the physical properties of the nanotubes. 

Song et al. [16] reported results relative to a four-point resistivity measurement on a large bundle of carbon nanotubes (60 um diameter and 350 tm in length between the two potential contacts). They explained their resistivity, magnetoresistance, and Hall effect results in terms of a conductor that could be modeled as a semimetal. Figures 4 (a) and (b) show the magnetic field dependence they observed on the high- and low-temperature MR, respectively. 

A cylindrical carbon nanotube, specified by can be considered a one-dimensional crystal with a fundamental lattice vector T, along the direction of the tube axis, of length given by[l,3]... 

The newest addition to the forms of elemental carbon is the nanotube. A carbon nanotube is a long cylinder of carbon atoms, connected together in much the same way as in a fullerene. Both the diameter and the length of carbon nano-tubes can vary. Properties of nanotubes, such as their ability to conduct electrical charge, change dramatically with the dimensions of the tube. Carbon nanotubes are under intensive study. For example, a carbon nanotube laid down on a silicon chip forms a molecular transistor. Such devices may eventually lead to further miniaturization of the chips that are at the heart of modem computers. 

Sato, Y. et al. (2005) Influence of length oncytotoxicity of multi-walled carbon nanotubes against human acute monocytic leukemia cell line THP-I in vitro and subcutaneous tissue of rats in vivo. Molecular BioSystems, 1 (2), 176-182. 

Becker, M.L. et al. (2007) Length-dependent uptake of DNA-wrapped single-walled carbon nanotubes. Advanced Materials, 19 (7), 939-945. 

Dissolution of full-length single-walled carbon nanotubes, J. Phys. Chem. B, 105 (2001) 2525-2528. 

Unlike the smaller, spheroidal fullerenes discussed previously, carbon nanotubes are not easily solubilized, even in organic solution. The reality is that all SWNTs and MWNTs are insoluble in all solvent systems. They also have a strong tendency to bind together and aggregate due to van der Waals attractive forces along the length of the nanotube. Since the length-to-diameter... 

An important route to solubilization of carbon nanotubes is to functionalize their surface to form groups that are more soluble in the desired solvent environment. It has been shown that acid treatment of nanotube bundles, particularly with HC1 or HNO3 at elevated temperatures, opens up the aggregate structure, reduces nanotube length, and facilitates dispersion (An et al., 2004 Kordas et al., 2006). Nitric acid treatment oxidizes the nanotubes at the defect sites of the outer graphene sheet, especially at the open ends (Hirsch, 2002 Alvaro et al., 2004), and creates carbonyl, carboxyl, and hydroxyl groups, which aid in their solubility in polar solvents. 

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