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[...]... to the structure of arc-formed carbonnanotubes (ACNTs) Both types of nanotubes, the ACNTs and the present PCNTs, appear to be essentially Russian Doll-like sets of elongated giant ful,lerenes[ll,12] Possible growth processes have 2 VAPOR-GROWN CARBON FIBERS AND PYROLYTIC CARBONNANOTUBES Vapor-grown carbon fibers have been prepared by catalyzed carbonization of aromatic carbon species using ultra-fine... unusual features of carbon- based materials that are relevant to the interpretation of experiments on carbonnanotubes that are now being so actively pursued A second goal of this book is thus to stimulate further progress in research on carbonnanotubes and related materials 'The birth of the field of carbonnanotubes is marked by the publication by Iijima of the observation of multi-walled nanotubes with... tube walls and well-organized graphite layers On the other hand, Pyrolytic carbonnanotubes from vapor-grown carbon fibers a 3 t b Fig 5 Heat-treated pyrolytic carbon nanotube and enlarged one (inserted), without deposited carbon Fig 4 Coexisting vapour-grown carbon fiber, with thicker diameter and hollow core, and carbon nanotubes, with thinner hollow core, (as-grown samples) PCNTs tend to have very... direction of the nanotubes The article by Kiang et al reviews the present status of the synthesis of single-wall nanotubes and the theoretical implications of these single-wall nanotubes The geometrical considerations governing the closure, helicity and interlayer distance of successive layers in multilayer carbonnanotubes are discussed in the paper by Setton Study of the structure of carbonnanotubes and... Thus, most of the experimental data available thus far relate to multi-wall carbonnanotubes and to bundles of nanotubes Thus, limited experimental information is available regarding quantum effects for carbonnanotubes in the one-dimensional limit A review of structural, transport, and susceptibility measurements on carbonnanotubes and related materials is given by Wang et al., where the interrelation... for the flexibility of graphene layers in carbonnanotubes The final section of the volume contains three complementary review articles on carbon nanoparticles The first by Y Saito reviews the state of knowledge about carbon cages encapsulating metal and carbide phases The structure of onion-like graphite particles, the spherical analog of the cylindrical carbon nanotubes, is reviewed by D Ugarte, the... 1994; accepted 10 February 1995) Abstract-The structure of as-grown and heat-treated pyrolytic carbon nanotubes (PCNTs) produced by hydrocarbon pyrolysis are discussed on the basis of a possible growth process The structures are compared with those of nanotubes obtained by the arc method (ACNT, arc-formed carbon nanotubes) PCNTs, with and without secondary pyrolytic deposition (which results in diameter... forms of carbon with larger micron diameters and carbon nanotubes with nanometer diameters from the viewpoint of "one-dimensional)) carbon structures as shown in Fig 1 The first class consists of graphite whiskers and ACNTs produced by arc methods, whereas the second encompasses vapor-grown carbon fibers and PCNTs produced by pyrolytic processes A third possibIe class would be polymer-based nanotubes. .. between carbon fullerenes, which are quantum dots, with carbon nanotubes, which are quantum wires Furthermore this seminal paper [2] has stimulated extensive theoretical and experimental research for the past five years and has led to the creation of a rapidly developing research field The direct linking of carbonnanotubes to graphite and the continuity in synthesis, structure and properties between carbon. .. Issi et al to quantum effects in carbon nanotubes, as observed in scanning tunneling spectroscopy, transport studies and magnetic susceptibility measurements The vibrational modes of carbonnanotubes is reviewed in the article by Eklund et al from both a theoretical standpoint and a summary of spectroscopy studies, while the mechanical that thermal properties of carbonnanotubes are reviewed in the article . of carbon nanotubes J. W. MINTMIRE and C. T. WHITE: Electronic and structural properties of carbon nanotubes C H. KIANG, W. A. GODDARD 111, R. BEYERS and D. S. BETHUNE: Carbon nanotubes. on carbon nanotubes. Carbon nanotubes have the same range of diameters as fullerenes, and are expected to show various kinds of size effects in their structures and properties. Carbon nanotubes. hand, Pyrolytic carbon nanotubes from vapor-grown carbon fibers 3 a t b Fig. 4. Coexisting vapour-grown carbon fiber, with thicker diameter and hollow core, and carbon nanotubes, with