Dispersive correction for the second- and the third-order nonlinear terms of the electrical energy density for a light-dielectric system

Optical and Quantum Electronics - Classification of hyperspectral image (HSI) is widely used for the study of remotely sensed images. Convolutional Neural Networks (CNNs) are one of the most...     

A Novel Method for Permeability Estimation from Micro-tomographic Images

Transport in Porous Media - A methodology has been developed to create a pore network model (PNM) from the geometrical/topological information extracted from the micro-tomographic images of a...     

Molecular Design of Carbazole-based Dyes and the Influence of Alkyl Substituent on the Performance of Dye-Sensitized Solar Cells

Carbazole is an alternant polycyclic aromatic hydrocarbon consisting of three fused rings with a large, aromatic system, containing nitrogen atom showing extensive electron delocalization. In this work, carbazole applied as π-conjugated bridge to construct electron donor–π–electron acceptor (D–π–A) organic dyes, where barbutiric acid and thiazolidine-2,4-dione as electron acceptor. The effects of these three acceptors and length of alkyl on the performance of the DSSCs were investigated systematically along with their photophysical and photo electrochemical properties. These series of organic dyes include (B-CH, B-C B, DT-CB, DB-CB). Our investigation indicate among dyes containing butyl as same donor, DT-CB exhibited the maximum overall conversion efficiency of 1.44% and from dyes by deferent electron donor B-CH shows conversion efficiency of 1.47%.     

A study of the optical properties and adhesion of zinc sulfide anti-reflection thin film coated on a germanium substrate

To conduct this study, zinc sulfide (ZnS) thin films deposited on germanium (Ge) substrates were prepared by an evaporation method. The effects of deposition rate and annealing on the optical properties and adhesion of the ZnS thin films were investigated. The transmission intensity and the X-ray diffraction (XRD) pattern of the samples showed that the transmittance of the samples decreases by increasing the evaporation rates. However, with the increase of the annealing temperature, crystallinity of the thin films improves which, in turn, results in the enhancement of the transmission intensity in a far infrared region. The maximum grain size was obtained at the annealing temperature of 225 °C. Our experimental results also show that evaporation rate and annealing influences the adhesion of ZnS thin films to Ge substrates.     

ZnS nanoparticles incorporated in polyaniline composite: Preparation and optical characterization

Hybrid polyaniline based composites incorporating zinc sulfide nanoparticles have been synthesized by using chemical oxidation technique. Morphological and optical properties of the nanocomposite were characterized by scanning electron microscopy, Fourier transform infrared and UV–Vis spectroscopy measurement. The results were compared with pure polyaniline. The characteristic FTIR peaks of polyaniline were found to shift to lower wave-number in nanocomposite. The band gap of nanocomposites increases and the refractive index of the nanocomposites decreases with increasing content of ZnS nanoparticles. These results showed the interaction between ZnS nanoparticles and polyaniline.     

DFT and MP2 Calculations on Tautomers and Water-Assisted Proton Transfer on 1,2,5-Oxadiazol-4,3-diamine

In this work a detailed quantum-chemical comparison of the relative stability of six tautomers of 1,2,5-oxadiazol-4,3-diamine studied in the gas phase and solution. Theoretical calculations are carried out by the density functional theory (DFT/B3LYP) and MP2 methods using the standard 311++G(d,p) basis set. The results indicate that A is the most stable form in the gas phase and also is the predominant tautomer in solution at the DFT and MP2 methods. The transition states of proton transfer reaction are calculated. The variation of dipole moments and charges on atoms are studied in various solvent. Specific solvent effects with addition of one water molecule near the electrophilic centers of tautomer investigated. Also the transition state of proton transfer assisted by a water molecule was investigated.     

Density functional theory of tautomerism and water-assisted proton transfer of glycoluril

Density functional theory and MP2 methods have been employed to study of proton transfer reaction in annular tautomerization of tetrahydroimidazo[4,5-d]imidazole-2,5(1H,3H)-dione (glycoluril). Ten different tautomers are possible for the tetrahydroimidazo[4,5-d]imidazole-2,5(1H,3H)-dione. For all molecules, the Gibbs free energy at 0 and 298 K was estimated. In addition variation of dipole moments and charges on atoms are studied in the gas phase and solution, the specific solvent effects with addition of one molecule of water near the electrophilic centers of tautomer and the NBO charges of atoms were investigated. NBO analysis shows that there is a strong interaction between nitrogen lone pairs and double bonds.     

Application of DFT and MP2 calculations on structural and water-assisted proton transfer in 3-amino-4-nitrofurazan

Density functional theory (DFT) and MP2 calculations have been employed to study of 3-amino-4-nitrofurazan molecule using the standard 6-311++G(d,p) basis set. The chemical properties of the 3-amino-4-nitrofurazan have been extensively studied. The geometries of molecules in the gas phase were optimized and compared with the crystallography of this substance. The results suggest that A form is the most stable form in the gas phase and it is the predominant tautomer in solution according to the DFT and MP2 calculations, respectively. In addition, variation of dipole moments in the gas phase, the specific solvent effects with addition of one molecule of water near the electrophilic centers of tautomers, the transition state of proton transfer assisted by a water molecule, the NBO charges of atoms and the potential energy surface were investigated. The calculated highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) are presented.     

Redefined fuzzy B-algebras

By two relations belonging to and quasi-coincidence (q) between fuzzy points and fuzzy sets, we define the concept of (α, β)-fuzzy subalgebras where α, β are any two of with . We state and prove some theorems in (α, β)-fuzzy B-algebras.