the storage capacity of hydrogen on na-decorated born nitride nanotubes (bnnts) is investigated by using density functional theory within quantum espresso and gaussian 09. the results obtained predict that a single na atom tends to occupy above the central region of the hexagonal rings in (5,0) and (3,3) bnnt structures with a binding energy of -2.67 and -4.28 ev/na-atom respectively. when a si...

background: the aim of the present study was to evaluate the relationship between the bone density of various regions of jaws and skeletal bones. materials and methods: a total of 110 patients with a mean age of 55.01 ± 10.77 years were selected for the purpose of the present descriptive study. dual x-ray energy absorptiometry (dxa) was carried out to determine bone mineral density (bmd) of the...

In this paper we consider the hermitian extension of the cross-ΨB-energy operator that we will denote by ΨH . In addition, cross energy terms are formalized through multivariate signals representation. We investigate the connection between the interaction energy function of ΨH and the cross-power spectral density (CPSD) of two complex valued signals. In particular, this link permits to use this...

The mass density and energy of visible photon is calculated as 10-8 Kgm-3 109jm3 respectively. Moreover it also observed that depend upon photons mass, wavelength, volume energy. This clear from figure 1, 2 literatures. Therefore the varies with masses photon, volume, etc.

A microscopic framework of nuclear energy density functionals is reviewed, which establishes a direct relation between low-energy QCD and nuclear structure, synthesizing effective field theory methods and principles of density functional theory. Guided by two closely related features of QCD in the lowenergy limit: a) in-medium changes of vacuum condensates, and b) spontaneous breaking of chiral...

We analyze the difference between the correlation energy as defined within the conventional quantum chemistry framework and its namesake in density-functional theory. Both quantities are rigorously defined concepts; one finds that E QC c ≥ E DF T c. We give numerical and analytical arguments suggesting that the numerical difference between the two rigorous quantities is small. Finally, approxim...

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...