Zero-Pressure Model and the Corresponding Temporal Evolution of a Time Dependent Cosmological Parameter

In this paper, we show that how the cosmological constant would behave if the universe was in a pressure-less epoch. The results are depicted for the three famous curvature based values of k, according to the standard model cosmology.     

Energy Conservation for a Scalar Field in Linear Gravity

In this paper we derive a Gaussian flux integral for a metric in the weak field limit. We shall prove that the energy integral for an approximately linear metric due to a scalar field, will possess a same form for the Newtonian mass.     

Single versus poly-crystalline layered oxide cathode materials for solid-state battery applications - a short review article

The recent developments in the application of single-crystalline (SC) cathode materials in solid-state batteries are discussed in this mini-review. The characteristics of SC and poly-crystalline (PC) cathode materials are explored, with emphasis on the kinetic and mechanical properties. The critical factors influencing their performance in liquid electrolyte and solid-state battery cells are investigated. Finally, the advantages and disadvantages of both morphologies are discussed and considerations to ensure a fair comparison between SC and PC cathodes in different systems are raised.     

Vacuum Domination in a Positively Curved Isotropic Universe

In this article we assume a universe in a vacuum domination era, possessing a constant equation of state and a constant positive curvature, elaborated by an isotropic FLRW metric. We investigate the correlations between the scale factor of this expanding universe, and the coordinate time.     

Theory of interfacial phase transitions in surfactant systems

The spin-1 Ising model, which is equivalent to the three-component lattice gas model, is used to study wetting transitions in three-component surfactant systems consisting of an oil, water, and a nonionic surfactant. Phase equilibria, interfacial profiles, and interfacial tensions for three-phase equilibrium are determined in mean field approximation, for a wide range of temperature and interaction parameters. Surfactant interaction parameters are found to strongly influence interfacial tensions, reducing them in some cases to ultralow values. Interfacial tensions are used to determine whether the middle phase, rich in surfactant, wets or does not wet the interface between the oil-rich and water-rich phases. By varying temperature and interaction parameters, a wetting transition is located and found to be of the first order. Comparison is made with recent experimental results on wetting transitions in ternary surfactant systems.This paper is dedicated to J. K. Percus in honor of his 65th birthday.     

The calculation of the magnetic exponent in real space differential renormalization

A calculational scheme is developed for the magnetic critical exponent of an Ising system in the context of a differential real space renormalization transformation. Successive approximations are worked out which require only information of the fixed point solution at a symmetry point. The convergence is reasonable.     

Factors contributing to academic achievement: a Bayesian structure equation modelling study

In Iran, high school graduates enter university after taking a very difficult entrance exam called the Konkoor. Therefore, only the top-performing students are admitted by universities to continue their bachelor's education in statistics. Surprisingly, statistically, most of such students fall into the following categories: (1) do not succeed in their education despite their excellent performance on the Konkoor and in high school; (2) graduate with a grade point average (GPA) that is considerably lower than their high school GPA; (3) continue their master's education in majors other than statistics and (4) try to find jobs unrelated to statistics. This article employs the well-known and powerful statistical technique, the Bayesian structural equation modelling (SEM), to study the academic success of recent graduates who have studied statistics at Shahid Beheshti University in Iran. This research: (i) considered academic success as a latent variable, which was measured by GPA and other academic success (see below) of students in the target population; (ii) employed the Bayesian SEM, which works properly for small sample sizes and ordinal variables; (iii), which is taken from the literature, developed five main factors that affected academic success and (iv) considered several standard psychological tests and measured characteristics such as ‘self-esteem’ and ‘anxiety’. We then study the impact of such factors on the academic success of the target population. Six factors that positively impact student academic success were identified in the following order of relative impact (from greatest to least): ‘Teaching–Evaluation’, ‘Learner’, ‘Environment’, ‘Family’, ‘Curriculum’ and ‘Teaching Knowledge’. Particularly, influential variables within each factor have also been noted.     

The Hidden Symmetries of Spin-1 Ising Lattice Gas for Usual Quantum Hamiltonians

In this letter, the most common quantum Hamiltonian is exploited in order to compare the definite equivalences, corresponding to possible spin values in a lattice gas model, to those in a spin-1 Ising model. Our approach also requires interpolating both results in a p-state clock model, in order to find the hidden symmetries of both under consideration models.