We illustrate the main features of a recently proposed method based on ensemble density functional theory to divide rigorously a complex molecular system into its parts [M.H. Cohen and A. Wasserman, J. Phys. Chem. A 111, 2229 (2007)]. The illustrative system is an analog of the hydrogen molecule for which analytic expressions for the densities of the parts (hydrogen “atoms”) are found along wit...

In this study, some mechanical properties of borided and unborided four steels were investigated. Boronizing of steels was performed by powder pack method at 1210 K for 4 h. The hardness of borides, boride layer thickness and room temperature tensile properties were measured and it was observed that hardness and tensile properties strongly depend on chemical composition of steels. In addition, ...

We illustrate the main features of a recently proposed method based on ensemble density functional theory to divide rigorously a complex molecular system into its parts (J. Phys. Chem. A 2007, 111, 2229). The illustrative system is an analog of the hydrogen molecule for which analytic expressions for the densities of the parts (hydrogen "atoms") are found along with the "partition potential" th...

Seasonal variation on physico-chemical quality of well water at Eloor industrial area, Kerala was studied. A total of 100 samples, 25 each during four different seasons, viz. summer, premonsoon, monsoon and post monsoon were collected during the year 2009 and analyzed for temperature, pH, total hardness, Chemical Oxygen Demand, concentration of nitrate, fluoride, iron, heavy metals like lead, m...

Formulas governing fixed orbital hardnesses and their relation to the hardness kernel are derived. It is shown how the orbital hardness matrix and its inverse matrix, the orbital softness matrix, may thus be directly calculated, and then the total chemical hardness, softness, and electronegativity of a molecular species. These quantities are calculated for the molecule HCN, using Dirac exchange...

influence of aluminum, gallium, indium- doping on the boron-nitride nanotubes (bnnts) investigated with density functional theory (dft) and hartreefock (hf) methods. for this purpose, the chemical shift of difference atomic nucleus was studied using the gauge included atomic orbital (giao) approch. in the following, structural parameter values, electrostatic potential, thermodynamic parameters,...

titanium nitride-copper (tin-cu) nanocomposite films were deposited onto stainless steel substrate using hollow cathode discharge ion plating technique. the influence of cu content in the range of 2-7 at.% on the microstructure, morphology and mechanical properties of deposited films were investigated. structural properties of the films were studied by x-ray diffraction pattern. topography of t...

Despite having some useful properties, stainless steels suffer from lack of suitable surface hardness. In this research electroless Ni-B-Tl coating was used with the aim to increase their surface hardness. The effects of Nickel chloride, Sodium borohydride, Thallium nitrate and Ethylendiamin on the chemical composition of coating were studied. To achieve an increase in hardness, the effects of ...