the density functional theory (dft) and the natural bond orbital (nbo) calculations basedmethod b3lyp/6-31g were carried out to study the interaction of dopamine with carbon nanotube.the nanotube used in this study, includes 60 c atoms (6, 6) type. relative and formation energies ofcompounds, muliken charges, occupancy, the highest occupied molecular orbital (homo) and thelowest unoccupied mole...

the n-(2-benzoyl-phenyl) oxalyl derivatives are important models for studying of three-centered intramolecular hydrogen bonding in organic molecules. the quantum theoretical calculations for two crystal structures of n-(2-benzoyl-phenyl) oxalyl (compounds i and ii) were performed by density functional theory (b3lyp method and 6-311+g* basis set). from the optimized structures, geometric paramet...

The electronic structures and the electrostatic potential of some amino derivatives of adamantane have been studied using the density functional theory. The partial atomic charges and nuclear quadrupole coupling constants (NQCC) of 14N nucleus of the considered molecules have been reported. The partial atomic charges are calculated with two methods for 14N nucleus: Mulliken charges and natural ...

Using natural bond orbital theory, aromatic stabilisation energies (NBO-ASEs) were calculated for neutral and cationic monoheterocyclic three-membered rings C2H2X(R)n (X = group 14-17 elements of rows 3-5; R F, H or SiH3; n 0-2). Generally, there was a decrease in the (anti)aromatic nature molecule moving down as either stabilizing overlap (aromaticity) destabilising interactions (antiaromatici...

Ultra-low sulfur steel has excellent resistance to pitting and hydrogen-induced cracking, is mainly used for gas pipeline steel, drilling structural parts of offshore platforms. This study reveals the limiting aspects desulfurization at slag–metal interface from perspective experimental theoretical calculations. Based on XPS results, quantitative analysis shows that relative contents Si O are d...

Imaging the three-dimensional atomic-scale structure of complex interfaces has been the goal of many recent studies, due to its importance to technologically relevant areas. Combining atom-probe tomography and aberration-corrected scanning transmission electron microscopy (STEM), we present an atomic-scale study of ultrathin (~5 nm) native oxide layers on niobium (Nb) and the formation of order...

Polarizable interaction potentials, parametrized using ab initio electronic structure calculations, have been used in molecular dynamics simulations to study the effect of cation composition on the ionic conductivity in the Zr(2)Y(2)O(7)-Y(3)NbO(7) system and to link the dynamical properties to the degree of lattice disorder. Across the composition range, this system retains a disordered fluori...

1. A highly purified sporopollenin fraction from Corylus avellana pollen was obtained using a gentle method employing hydrolyzing enzymes (pronase, lipase, cellulase, amylase, cellulysin) and an exhaustive extraction using different solvents. 2. The sporopollenin fractions were degraded by potash-fusion and nitrobenzene oxidation and the low molecular decomposition products were analyzed by TLC...