We present an extensive first-principles study of the phonons in boron nitride nanotubes using density functional perturbation theory in the local density approximation. Based on the nonsymmorphic rod-group symmetry of the tubes, the Ramanand infrared-active modes at the G point of the one-dimensional Brillouin zone are evaluated. For zigzag and chiral nanotubes, the set of infrared-active mode...

We propose a simple realization of topological edge states in zigzag chains of plasmonic nanoparticles, mimicking the Kitaev model of Majorana fermions. We demonstrate the one-to-one correspondence between the coupled dipole equations in the zigzag plasmonic chain and the Bogoliubov-de-Gennes equations for the quantum wire on top of superconductor and support the analytical theory by the full-w...

A family of small graphene patches, i.e., rectangular polyaromatic hydrocarbons (PAHs), that have both zigzag and armchair edges is investigated to establish their ground state electronic structure. Broken symmetry density functional theory (DFT) and plane wave DFT were used to characterize the onset of diradical character via relative energies of open-shell and closed-shell singlet states. The...

stabilities and quantum molecular descriptors of cyclophoshphamide (an anticancer drug)-functionalized (8,0) zigzag and (4,4) armchair carbon nanotubes (cnts) complexes in water were studied using density functional theory (dft) calculations. two attachments namely the sidewall- and tip-attachments are considered for the model constructions. calculations of the total electronic energy (et) and ...

afinite element model of a bias truck tire under static vertical load using a global/local technique is designed in two parts. in the first part a previously created model for radial tires is developed to take the constructional variables of bias tires into account. it is shown that the technique can successfully be used for bias tires. the main challenge here is the selection of the initial la...

this study investigated the impact of using the technique of self-monitoring on non-academic efl learners’ composition writing. fifty female students studying english at navid english institute in shiraz, iran were chosen based on the results of a proficiency test. they were all 16-20 years old and were intermediate learners of english who were divided into two control and experimental groups a...

We present first principles calculations of the electronic structure of small carbon nanotubes with different chiral angles theta and different diameters (d<1 nm). Results are obtained with a full potential method based on the density functional theory (DFT), with the local density approximation (LDA). We compare the band structure and density of states (DOS) of chiral nanotubes with those of z...

In the mean-variance-skewness-kurtosis framework, this paper discusses an uncertain higher-order moment portfolio selection problem when security returns are given by experts’ evaluations. Based on uncertainty theory and the assumption that the security returns are zigzag uncertain variables, an uncertain multi-objective portfolio optimization model is proposed by considering the maximization o...