Effects of strain on shot noise properties in graphene superlattices

In this paper the transmission and the shot noise properties through the strain-inducedgraphene superlattices are studied. It is found that for the zigzag direction strain theFano factor shows a peak at new Dirac-like point and the position of the new Dirac pointvaries against the strain. Also, Fano factor has an oscillatory behavior with respect tostrain strength and the oscillation period decreases by increasing the number of barriers.However, for the armchair direction strain the transmission can be blocked by the electricbarrier and the Fano factor approaches 1, this is different from the zigzag directionstrain.     

Nanocrystalline TiO2-HClO4:A novel,efficient and recyclable catalyst for the chemoselective N-Boc protection of amines under solvent-free conditions

Nanocrystalline TiO₂-HClO₄,as newly reported catalyst,has been used as an efficient and reusable catalyst for the chemoselective N-Boc protection of amines.The clean,mild acidity condition, quantitative yields of products,short reaction time and low reaction temperature are attractive features of this reaction.In practice,this method is a combination of a satisfactory synthesis and more significantly easy product isolation and purification.     

Functionalization of BN nanosheet with N2H4 may be feasible in the presence of Stone–Wales defect

Following recent experimental works, herein we investigated chemical functionalization of a BN graphene-like sheet with hydrazine (N₂H₄) molecule based on the density functional theory. We found that the functionalization of the pristine sheet is not possible; while the presence of some structural defects such as Stone–Wales is essential to make it feasible. Functionalization energy of the defected sheet is calculated to be in the range of ?6.1 to ?7.4 kcal/mol at B3LYP/6-31G (d) level. Based on the obtained results, the functionalized BN sheet is found to be more soluble in water in comparison with the pristine sheet which is in good agreement with previous experimental reports. Also, it was found that the electronic properties of the defected sheet are slightly changed upon the chemical functionalization.     

A Theoretical Study of OH and OCH3 Free Radical Adsorption on a Nanosized Tube of BC2N

By using density functional theory calculations, we have investigated the adsorption of OH and OCH₃ free radicals on a BC₂N nanotube based on the energetic, electronic and geometric properties. The adsorption of radicals on the top of a B atom is more favorable than that on the other sites and reaction energies have been calculated to be in the range of ?0.57 to ?1.48 eV for OH and ?0.27 to ?1.19 eV for OCH₃. It was found that the adsorption of radicals may facilitate the electron emission from the BC₂N nanotube surface by decreasing the work function due to the charge transfer which occurs between the tube and radicals. Also, HOMO/LUMO gap of the tube is significantly decreased, which may result in the increase of the electrical conductivity of the tube.