Dynamic measurement of electrical conductivity of carbon nanotubes during mechanical deformation by nanoprobe manipulation in transmission electron microscopy

We report a new route to fabricating carbon nanotubes and nanotube interconnects. Insulating Si nanochains covered with hydrocarbon, which are a kind of Si nanowire, can be transformed into distorted nanotubes of carbon by Joule heating. Transmission electron microscopy observations of the transformation reveal that first a surface carbon shell is formed, and then oxide evaporates by Joule heating forming a nanotube.

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Mechanical Properties and Microstructure Evolution of Typical Over-Aging State Al-Zn-Mg-Cu Alloy during Thermal Exposure

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1026.84 ◽

2021 ◽

Vol 1026 ◽

pp. 84-92

Author(s):

Tao Qian Cheng ◽

Zhi Hui Li

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Mechanical Property ◽

Electrical Conductivity ◽

Transmission Electron Microscopy ◽

Tensile Strength ◽

Thermal Exposure ◽

Cu Alloy ◽

Transmission Electron ◽

Thermal Stability Of

Al-Zn-Mg-Cu alloy have been widely used in aerospace industry. However, there is still a lack of research on thermal stability of Al-Zn-Mg-Cu alloy products. In the present work, an Al-Zn-Mg-Cu alloy with T79 and T74 states was placed in the corresponding environment for thermal exposure experiments. Performance was measured by tensile strength, hardness and electrical conductivity. In this paper, precipitation observation was analyzed by transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HREM). The precipitations of T79 state alloy were GPⅡ zone, η' phase and η phase while the ultimate tensile strength, hardness and electrical conductivity were 571MPa, 188.2HV and 22.2MS×m-1, respectively. The mechanical property of T79 state alloy decreased to 530MPa and 168.5HV after thermal exposure. The diameter of precipitate increased and the precipitations become η' and η phase at the same time. During the entire thermal exposure, T74 state alloy had the same mechanical property trend as T79 state alloy. The precipitate diameter also increased while the types of precipitate did not change under thermal exposure. The size of precipitates affected the choice of dislocation passing through the particles to affect the mechanical properties.

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Visualization of thermal conduction in carbon nanotubes by in-situ transmission electron microscopy

10.22443/rms.emc2020.947 ◽

2021 ◽

Author(s):

Kaori Hirahara ◽

Keyword(s):

Electron Microscopy ◽

Carbon Nanotubes ◽

Transmission Electron Microscopy ◽

Thermal Conduction ◽

Transmission Electron

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Novel Nanohybrids Based on Supramolecular Assemblies of Meso-tetrakis-(4-sulfonatophenyl) Porphyrin J-aggregates and Amine-Functionalized Carbon Nanotubes

Nanomaterials ◽

10.3390/nano10040669 ◽

2020 ◽

Vol 10 (4) ◽

pp. 669 ◽

Cited By ~ 3

Author(s):

Mariachiara Trapani ◽

Antonino Mazzaglia ◽

Anna Piperno ◽

Annalaura Cordaro ◽

Roberto Zagami ◽

...

Keyword(s):

Electron Microscopy ◽

Carbon Nanotubes ◽

Transmission Electron Microscopy ◽

Fluorescence Emission ◽

Resonance Light Scattering ◽

Therapeutic Window ◽

Multiwalled Carbon ◽

Experimental Conditions ◽

Transmission Electron ◽

J Aggregates

The ability of multiwalled carbon nanotubes (MWCNTs) covalently functionalized with polyamine chains of different length (ethylenediamine, EDA and tetraethylenepentamine, EPA) to induce the J-aggregation of meso-tetrakis(4-sulfonatophenyl)porphyrin (TPPS) was investigated in different experimental conditions. Under mild acidic conditions, protonated amino groups allow for the assembly by electrostatic interaction with the diacid form of TPPS, leading to hybrid nanomaterials. The presence of only one pendant amino group for a chain in EDA does not lead to any aggregation, whereas EPA (with four amine groups for chain) is effective in inducing J-aggregation using different mixing protocols. These nanohybrids have been characterized through UV/Vis extinction, fluorescence emission, resonance light scattering and circular dichroism spectroscopy. Their morphology and chemical composition have been elucidated through transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM). TEM and STEM analysis evidence single or bundles of MWCNTs in contact with TPPS J-aggregates nanotubes. The nanohybrids are quite stable for days, even in aqueous solutions mimicking physiological medium (NaCl 0.15 M). This property, together with their peculiar optical features in the therapeutic window of visible spectrum, make them potentially useful for biomedical applications.

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In Situ Filling of Fe/Ni Oxide Nanowire into Carbon Nanotubes Doped with Nitrogen in CH4/H2/Air Plasma

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.15.51 ◽

2011 ◽

Vol 15 ◽

pp. 51-56 ◽

Cited By ~ 1

Author(s):

Xin Wang ◽

Ya Yu Wang ◽

Wei Tao Zheng ◽

Zan Wang

Keyword(s):

Electron Microscopy ◽

Carbon Nanotubes ◽

Transmission Electron Microscopy ◽

Chemical Vapor ◽

Air Plasma ◽

Catalyst Film ◽

Metal Oxide Nanoparticle ◽

Transmission Electron ◽

Nitrogen Doped Carbon ◽

Ni Oxide

Nitrogen-doped carbon nanotubes (N-CNTs) were synthesized using air as the nitrogen carrier gas and CH4 as the carbon source by plasma-enhanced chemical vapor deposition over a thin catalyst film of Fe50Ni50. Transmission electron microscopy and high resolution transmission electron microscopy measurements have indicated that the N-CNTs grew with a tip-type growth mode. When H2 was added to the CH4/air plasmas during the N-CNTs growth stage, it was found that Fe/Ni oxide nanowire was filled into the nanotube. However, without adding H2 in the CH4/air mixture plasma, only metal oxide nanoparticle was found on the tip of the N-CNT.

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