carbon nanotubes

Dear Colleagues,

I invite you to read our recent paper on hierarchically architected foams published in Extreme Mechanics Letters: Read full article here.

Abstract

https://doi.org/10.1016/j.memsci.2019.03.062 This work presents the multilayer transverse flow carbon nanotube (CNT) membrane (TFCM), which resembles vertically aligned CNT arrays, as an alternative candidate for efficient desalination. Using molecular dynamics, this work shows that multilayer TFCM can provide permeability and salt rejection on par with its single layer counterpart.

https://doi.org/10.1039/C8CP01191E We investigate the effect of varying carbon nanotube (CNT) size on the desalination performance through slit confinements formed by horizontally aligned CNTs stacked on top of one another. By increasing the CNT size, the results obtained from this study indicate a corresponding increase in the water flow rate, accompanied by a slight reduction in salt rejection performance.

In this work, a theoretical study is performed to quantitatively understand the van der Waals interactions between single-walled carbon nanotubes (SWNTs) and sapphire substrates. The energetically preferred alignment directions of SWNTs on A-, R- and M-planes and the random alignment on the C-plane predicted by this study are all in good agreement with experiments. It is also shown that smaller SWNTs have better alignment than larger SWNTs due to their stronger interaction with sapphire substrate.

In the attached paper, recently appeared on Computer Physics Communications, we have proposed an analytical benchmark and a simple consistent Mathematica program for graphene and carbon nanotubes, that may serve to test any molecular dynamics code implemented with REBO potentials. By exploiting the benchmark, we checked results produced by LAMMPS (Large-scale Atomic/Molecular Massively Parallel Simulator) when adopting the second generation Brenner potential, we made evident that this code in its current implementation produces results which are offset from those of the benchmark by a significant amount, and provided evidence of the reason.

I'm posting a few experimental studies we have conducted on the dynamic behavior of hierarchical fibrous materials, using vertically aligned carbon nanotubes as a model material. I hope these will be useful to those who are interested in buckle-instabilities, multiscale behavior, and energy absorption mechanisms.

An overview:

In the attached paper we have shown that graphene and carbon nanotubes are in a self-stress state in their natural equilibrium state, that is, the state prior to the application of external loads. We have identified different sources of self-stresses and accurately evaluated them; we have shown that they are by no means negligible with respect to load-related nanostresses.

http://dx.doi.org/10.1016/j.jmps.2015.07.016

Composites reinforced by thinner fibers are intensively studied in recent years and expected to have better
mechanical properties. With development of nanotechnology, the diameter of fiber can be as thin as
several nanometers, such as nanofibers and nanotubes. Then, do these thinner fibers definitely result in
composites with better mechanical properties? In this paper, the toughening effect of reinforcing fibers in
composites is investigated based on the three-level failure analysis model. It is found that thinner

Complex structures consisting of intertwined, nominally vertical carbon nanotubes (CNTs) are called turfs. Under uniform compression experiments, CNT turfs exhibit irreversible collective buckling of a layer preceded by reorientation of CNT segments. Experimentally observed independence of the buckling stress and the buckling wavelength on the turf width suggests the existence of an intrinsic material length.

Applications are invited for the position of "Post‐doctoral Research Fellow" as part of a multi-disciplinary collaborative project funded by Lockheed Martin. The project's Principal Investigators are:

Dr. Kumar Shanmugam, Mechanical Engineering
Dr. Matteo Chiesa, Materials Science & Engineering
Dr. Amal Al Ghaferi, Materials Science & Engineering

We systematically investigated the interesting electric response of the aligned CNT ribbons under mechanical strain. We found that CNTs slide on a PDMS substrate under tension, but buckle under compression (releasing). Such an irreversible mechanical deformation is responsible for the observed irreversibility in the electric resistance upon the first stretching/releasing.

Hi,

The Irish Research Council (http://www.ircset.ie/tabid/64/default.aspx) has a funding scheme for postdoctoral researchers. I am seeking someone to submit an application to IRCSET to obtain funding to work within my group, in Modelling of CNT-based nanocomposites. The chances of success are high for candidates with a good research record. The deadline for applications is December 8th.

What a methodology and a software designed for large-scale engineering problems have to do with carbon nanotubes? See J. Nanotechnol. Eng. Med. 1, 041009 (2010).