in this paper, we have used density functional perturbation theory (dfpt) and pseudo-potential method to calculate the phonon spectrum, phonon density of states (dos), specific heat capacity and mechanical properties of (5,5) armchair and (9,0) zigzag single wall carbon nanotubes (swcnts). our calculations show that young’s modulusfor (5,5) and (9,0) nanotubesare higher than 1tpa. we have also ...

excellent mechanical properties of carbon nanotubes (cnts) make them outstanding candidate reinforcements to enhance mechanical properties of conventional composites. the glass/polyester composites are widely used in many industries and applications. improving the mechanical properties of such composites with addition of cnts can increase their applications. in this research, multi-walled carbo...

in this paper functionalized multiwall carbon nanotubes (fmwcnt) were modified using doxycycline, containing reactable nitrogen, which can attach chemically to functionalized mwcnt. the synthesized nano compounds were characterized by fourier transform infrared spectroscopy (ft-ir) and raman spectroscopy. these spectrums proved the existence of nitrogen atoms of amide functional groups. the mor...

We present transport measurements of ferromagnetically contacted carbon nanotubes. In both singleand multi-walled nanotube devices, a spin valve effect is observed due to spin-polarized transport. In one single-walled nanotube device, the spin-valve effect is suppressed as the influence of Coulomb charging is observed at around 10 K. To help understand the interplay between the Coulomb charging...

An extremely compact and versatile near-infrared two-color femtosecond pump-probe spectroscopy apparatus based on an amplified Erfiber laser system is presented and applied to the characterization of the relaxation dynamics of single-wall carbon nanotubes with fundamental absorption in the 2 μm spectral region. By implementing a fast-scan technique, dynamics as long as 3 ps are acquired in 5 s ...

Micro-sorbent traps referred to as microtraps serve as integrated concentration-injection devices for continuous monitoring in gas phase streams. The application of carbon nanotubes as unique sorbents for the fabrication of microtraps for the nano-scale adsorption/desorption of volatile organic molecules is presented in this paper. The microtrap application requires high adsorption capacity as ...

We have continued our efforts in the J. R. Macdonald Laboratory directed toward the study of electronic excitations and dynamics in carbon nanotubes excited by femtosecond pump-probe laser pulses generated by the ultra-fast Ti:Sapphire Kansas Light Source, KLS. We use time-of-flight of electrons emitted from carbon nanotubes to deduce the energy and temporal behavior of the electronic states of...

Control over chemical functionalization is a crucial point in the field of nanotechnology. Herein, we present the covalent functionalization of several carbon nanoforms (single-walled carbon nanotubes, double-walled carbon nanotubes, multi-walled carbon nanotubes and carbon nanohorns) by means of diphenyl dichalcogenides. These ones show different reactivity to the nanomaterials and are able to...

X-ray Compton scattering measurements of the electron momentum distribution in water confined in both single-walled and double-walled carbon nanotubes (SWNT and DWNT), as a function of temperature and confinement size are presented here together with earlier measurements of the proton momentum distribution in the same systems using neutron Compton scattering. These studies provide a coherent pi...

In the present work, effect of von Karman geometric nonlinearity on the vibration characteristics of a Y-shaped single walled carbon nanotube (Y-SWCNT) conveying viscose fluid is investigated based on Euler Bernoulli beam (EBB) model. The Y-SWCNT is also subjected to a longitudinal magnetic field which produces Lorentz force in transverse direction. In order to consider the small scale effects,...