by employing the theoretical method based on tight-binding, we study electronic band structure of single-wall carbon nanotube (cnt) superlattices, which the system is the made of the junction between the zigzag and armchair carbon nanotubes. exactly at the place of connection, it is appeared the pentagon–heptagon pairs as topological defect in carbon hexagonal network. the calculations are base...

In this paper, an atomistic based finite element model is developed to investigate the influence of topological defects on mechanical properties of graphene. The general in-plane stiffness matrix of the hexagonal network structure of graphene is found. Effective elastic modulus of a carbon ring is determined from the equivalence of molecular potential energy related to stretch and angular defor...

Gradient-corrected density functional theory (DFT) computations were performed to investigate the geometry, electronic property, formation energy, and reactivity of Stone-Wales (SW) defects in zigzag-edge and armchair-edge boron nitride nanoribbons (BNNRs). The formation energies of SW defects increase with an increase in the widths of BNNRs and are orientation-dependent. SW defects considerabl...

To explore the possibility of using graphene based biosensor, adsorption of hydrogen peroxide on graphene has been investigated using density functional theory. The electronic properties of defect free and defective graphene in the presence of different number of hydrogen peroxide have been studied. The graphene with the most stable configuration defect named as SW defect is considered. The hig...

Plane-wave density functional theory has been used to study oxygen adsorption on graphene, graphite, and (12,0) zigzag single-walled carbon nanotubes with without Stone–Wales (SW) single-vacancy (SV) defects understand the role of carbonaceous material reactivity. Atomic leads formation an epoxide defect-free graphene graphite ether exterior wall SW-defected materials. O2 chemisorption is endot...

to explore the possibility of using graphene based biosensor, adsorption of hydrogen peroxide on graphene has been investigated using density functional theory. the electronic properties of defect free and defective graphene in the presence of different number of hydrogen peroxide have been studied. the graphene with the most stable configuration defect named as sw defect is considered. the hig...

Molecular dynamic simulation method has been employed to consider the critical buckling force, pressure, and strain of pristine and defected single-walled carbon nanotube (SWCNT) under axial compression. Effects of length, radius, chirality, Stone-Wales (SW) defect, and single vacancy (SV) defect on buckling behavior of SWCNTs have been studied. Obtained results indicate that axial stability of...

It has been shown that the two different orientations of Stone-Wales (SW) defects, i.e. longitudinal and circumferential SW defects, on carbon nanotubes (CNTs) result in two different electronic structures. Based on density functional theory we have shown that the longitudinal SW defects do not open a bandgap near the Fermi energy, while a relatively small bandgap emerges in tubes with circumfe...

The noncontact and wide-band characteristics of the ultrasonic signal excited by laser make it widely used in nondestructive detection. In this paper, finite element method is to simulate multiple modes responses them metal defects. simulation shows that changes Rayleigh-wave (RW) shear-wave (SW) can be research surface crack internal defect sample respectively. By analyzing reflected wave RW S...