Rapid motion of liquid mercury column in carbon nanotubes driven by temperature gradient

The thermal conductivity of various carbon nanotubes with defects or intramolecular junctions was studied using nonequilibrium molecular dynamics approach. The results show that the thermal conductivity of both armchair and zigzag carbon nanotubes increased with the decrease of the radius of the tube. The thermal conductivity of armchair tube is higher than that of zigzag tube when the radii of the two tubes are kept almost same. Discontinuities appear on the temperature profile along the tube axial at the region of IMJ, resulting in the large temperature gradient and thus lower thermal conductivity of(n,n)/(m,0)tube with one IMJ and(m,0)/(n,n)/(m,0)tube with two IMJs. For the(m,0)/(n,n)/(m,0)tube with two IMJs, phonon mean free path of the middle(n,n)tube is much smaller than that of the isolate(n,n)tube.

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Pressure control model for transport of liquid mercury in carbon nanotubes

Applied Physics Letters ◽

10.1063/1.2720744 ◽

2007 ◽

Vol 90 (14) ◽

pp. 144105 ◽

Cited By ~ 10

Author(s):

H. W. Zhang ◽

Z. Q. Zhang ◽

L. Wang ◽

Y. G. Zheng ◽

J. B. Wang ◽

...

Keyword(s):

Carbon Nanotubes ◽

Pressure Control ◽

Control Model ◽

Liquid Mercury

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Effect of Temperature Gradient near the Target and Gas Flow Rate on the Diameter Distribution of Single-Walled Carbon Nanotubes Grown by the Laser Ablation Technique

MRS Proceedings ◽

10.1557/proc-633-a13.30 ◽

2000 ◽

Vol 633 ◽

Author(s):

Rahul Sen ◽

Hiromichi Kataura ◽

Yohsuke Ohtsuka ◽

Toshinobu Ishigaki ◽

Shinzo Suzuki ◽

...

Keyword(s):

Carbon Nanotubes ◽

Laser Ablation ◽

Temperature Gradient ◽

Flow Rate ◽

Gas Flow ◽

Single Walled Carbon Nanotubes ◽

Diameter Distribution ◽

Gas Flow Rate ◽

Single Walled Carbon ◽

Walled Carbon Nanotubes

AbstractGas dynamic and time resolved imaging studies have been performed on the growth of single-walled carbon nanotubes (SWNTs) in the laser ablation process. SWNTs were synthesized by laser ablation of Ni-Co catalyzed graphite targets at 1200°C under argon flow. The effects of the temperature gradient near the target and the gas flow rate were studied in order to understand the effect of gas dynamics over the diameter distribution of SWNTs. The gas flow rate affects the diameter distribution of SWNTs especially when the growth species flow through a large temperature gradient. Scattering images from the growth species at different flow rates was recorded by high-speed video imaging. The results indicate that the velocities of these species are dependent on the gas flow rate but this dependence is evident 30 ms after the laser ablation. These findings are used to estimate the time period for the nucleation and the growth of SWNTs.

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Mass Transport Induced by Heat Current in Carbon Nanotubes

Journal of Nanomaterials ◽

10.1155/2013/386068 ◽

2013 ◽

Vol 2013 ◽

pp. 1-4 ◽

Cited By ~ 1

Author(s):

Wei-Rong Zhong ◽

Zhi-Cheng Xu ◽

Ming-Ming Yang ◽

Bao-Quan Ai

Keyword(s):

Carbon Nanotubes ◽

Temperature Gradient ◽

Mass Transport ◽

Mechanical Energy ◽

Physical Factor ◽

Temperature Gradients ◽

Heat Current ◽

Alternative Route ◽

Helium Atoms ◽

Fundamental Physical

Transport of helium atoms in the carbon nanotubes is investigated in the presence of temperature gradients. The heat current flowing along the carbon nanotubes can induce a stable directed transport of helium; it is demonstrated that the heat current density rather than the temperature gradient performs as a fundamental physical factor to the mass transport. We provide an alternative route to control the mass transport by using heat. Our results reported here are also relevant for understanding the transition from thermal energy to mechanical energy.

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Temperature gradient chemical vapor deposition of vertically aligned carbon nanotubes

Carbon ◽

10.1016/j.carbon.2012.11.046 ◽

2013 ◽

Vol 54 ◽

pp. 343-352 ◽

Cited By ~ 19

Author(s):

Seul Ki Youn ◽

Christos E. Frouzakis ◽

Baskar Pagadala Gopi ◽

John Robertson ◽

Kenneth B.K. Teo ◽

...

Keyword(s):

Carbon Nanotubes ◽

Chemical Vapor Deposition ◽

Temperature Gradient ◽

Vapor Deposition ◽

Chemical Vapor ◽

Vertically Aligned Carbon Nanotubes ◽

Aligned Carbon Nanotubes ◽

Vertically Aligned

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Pressure control model for transport of liquid mercury in carbon nanotubes

Acta Physica Sinica ◽

10.7498/aps.57.1019 ◽

2008 ◽

Vol 57 (2) ◽

pp. 1019

Author(s):

Zhang Zhong-Qiang ◽

Zhang Hong-Wu ◽

Wang Lei ◽

Zheng Yong-Gang ◽

Wang Jin-Bao

Keyword(s):

Carbon Nanotubes ◽

Pressure Control ◽

Control Model ◽

Liquid Mercury

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Structural phenomena in the growth of carbon nanotubes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100149581 ◽

1993 ◽

Vol 51 ◽

pp. 750-751

Author(s):

Jun Jiao

Keyword(s):

Carbon Nanotubes ◽

Growth Mechanism ◽

Carbonaceous Material ◽

Cluster Growth ◽

Structural Elements ◽

Rich Variety ◽

Different Shapes ◽

Point To Point

HREM studies of the carbonaceous material deposited on the cathode of a Huffman-Krätschmer arc reactor have shown a rich variety of multiple-walled nano-clusters of different shapes and forms. The preparation of the samples, as well as the variety of cluster shapes, including triangular, rhombohedral and pentagonal projections, are described elsewhere.The close registry imposed on the nanotubes, focuses attention on the cluster growth mechanism. The strict parallelism in the graphitic separation of the tube walls is maintained through changes of form and size, often leading to 180° turns, and accommodating neighboring clusters and defects. Iijima et. al. have proposed a growth scheme in terms of pentagonal and heptagonal defects and their combinations in a hexagonal graphitic matrix, the first bending the surface inward, and the second outward. We report here HREM observations that support Iijima’s suggestions, and add some new features that refine the interpretation of the growth mechanism. The structural elements of our observations are briefly summarized in the following four micrographs, taken in a Hitachi H-8100 TEM operating at an accelerating voltage of 200 kV and with a point-to-point resolution of 0.20 nm.

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