An analytical treatment of the electron screening effect within an active-electron model is given for positronium formation from helium atoms. A first-order distorted wave approximation with correct boundary conditions is applied to evaluate the transition amplitude. In the range of impact energy for which the introduced perturbative approach is valid, both the total and differential cross sect...

the hot charging of continuously cast slabs steel is usually considered an effective method to reduce theenergy consumption in the hot rolling mills. in this work the application and optimizing of hot charging ofcontinuously cast slab in mobareke steel company has been investigated. mathematical relationship betweenthe cooling time of the stack of slabs and its mass average temperature is descr...

The Coulomb force applied by an electric field on any charge present in a dielectric liquid may cause fluid motion. At high applied electric fields in an insulating liquid, electric charge carriers are created at metallic/liquid interfaces, a process referred to as ion injection, and result from electrochemical reactions. In this article we deals with the problem of electro thermal convection i...

based on the {s+, i-} pathway, the concentration of surfactant and surface charge density of silanolate groups control the phase transition from lamellar, to hexagonal through cubic form. the high surface charge density of silanolate groups was observed for the lamellar phase. with decrease of molar concentration of surfactant on the gel, the yield of reaction decreases and the stability of mes...

molecular modeling analysis of charge density and heat of fornation by pm3 method as well as c, h nmr and 2d-nmr measurements of histidine (substrate) and some of its derivatives as histidine decarboxylase inhibitors were performed. it was established that the atom, usually nitrogen, which forms internal aldimine with pyridoxal5 -phosphate (plp), (coenzyme), has negative and almost equal charge...

background: antimicrobial peptides with relative length (2-100 amino acids) and positive charge (pure charge (+9)-(+2)) are amphiphilic that isolated from a wide range of animals. recently, these peptides have been known as a part of innate immune response. nowadays, more than 500 antimicrobial peptides from animals have been reported. objectives: the aim of this study was to evaluate the anti-...

in the present work, the structural and electronic properties, and conductivity of (5,5) and (6,6) single walled carbon nanotubes in the ground state have done by using the hartree-fock and density functional theory dft-b3lyp/6-31g* level. delocalization of charge density between the bonding or lone pair and antibonding orbitals calculated by nbo (natural bond orbital) analysis. these methods a...

M06-2X functional was employed to study halogen-π interactions in X-C2-Y…C8H8 complexes (X, Y=H, F, Cl, and Br). In fact, interactions of mono- or di-halogenated acetylenes and planar cyclooctatetraene as an anti-aromatic π system were considered. Relationship between binding energies of the complexes and charge transfer effects was investigated. Also, electronic charge density values were calc...

In this theoretical study, we focus on a kind of danunarane sapogenins. This molecule optimized in venoussolvent media such as heptao, carbontetrachloride, toluene. tetrahydrofurane, dichloroethane, ethanol, methanol,dimethylsulfoxide and water using the self-consistent reaction field model. This process depends on either thereaction potential function of the solvent or charge transfer operator...