623 research outputs found

    Chains of Carbon Nanotetrahedra/Nanoribbons

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    Flattening of a carbon nanotube results in the formation of a carbon nanoribbon with well-defined edges. In addition, a switching of the flattening direction by about a right angle yields a carbon nanotetrahedron at the switching point in a nanoribbon. Here, we report that chains of carbon nanotetrahedra/nanoribbons are formed via sequential switching of the flattening direction of multiwalled carbon nanotubes, in which neighboring two nanotetrahedra are connected by a short nanoribbon, namely a flattened nanotube. We suggest that the formation of nanotetrahedra chains is caused by a quasi-periodic instability of catalyst iron nanoparticles during the chemical vapor deposition growth. In addition, two adjoining carbon nanotetrahedra were found

    Optimizing Growth Conditions for Coaxial Multi-Walled Carbon Nanotubes

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    Coaxial multi-walled carbon nanotubes have a multi-layered structure in which a core multi-walled carbon nanotube is grown inside a sheath multi-walled nanotube from a metal-catalyst nanoparticle. In this paper, we report the optimum conditions to grow coaxial multi-walled carbon nanotubes by chemical vapor deposition. The coaxial nanotubes are studied by means of transmission electron microscopy to reveal their crystallinity and morphology. Our results show that chemical vapor deposition growth at around 1000°C with a 0.04–0.07 mg/cm^3 dose of palmitic acid yields the best result

    Estimating dynamics of fern species richness and assemblages for 30 years in Japan capital and along planning belt of linear motor car from Tokyo to Nagoya

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    We surveyed species density of ferns in Musashi (Tokyo and Saitama Prefs.), around capital of Japan, and planning belt of Linea express of 250km from Tokyo to Nagoya during 1997-2017, considering with records 30 years (mainly 1960-1980). The species richness (species richness per 10km X 10km) and similarity of species assemblages represented by species overlap were recorded and calculated between them of the past and present. Recent species richness is about half or less and the similarity ranged 0-48% in Musashi and 20-50% in the similarity along the Linea express planning belt.ArticleForestry Research and Engineering: International Journal. 2(2):68-73 (2018)journal articl
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