In this article, the crystallization of polyethylene is investigated by the modified weighted density approximation. Also, a direct correlation function of polyethylene based on the RISM theory is used. The free energy of a polyethylene is calculated using the density functional theory. The crystallization and also the solid and liquid densities of polyethylene are calculated and compared...

In this work an analytical equation of state has been employed to calculate the PVT properties ofternary refrigerant mixtures. The theoretical EoS is that of Ihm, Song and Mason, which is based onstatistical-mechanical perturbation theory, and the two constants are enthalpy of vaporization ΔHvapand molar density ρnb, both at the normal boiling temperature. The following three temperaturedepende...

Possible transition between two phases of supercooled liquid water, namely the low- and high-density liquid water, has been only predicted to occur below 230 K from molecular dynamics (MD) simulation. However, such a phase transition cannot be detected in the laboratory because of the so-called "no-man's land" under deeply supercooled condition, where only crystalline ices have been observed. H...

Gelled propellants are improved propellants that can be considered as the final extension of liquid propellants. High specific impulse, good density and safety better than that of both solid and liquid propellants are advantages of the gel propellants. They are made by addition a suitable gellant to liquid propellants. In this research, nano Al particles have been used in UDMH gel fuel. The gel...

Molecular dynamics and Langevin dynamics simulations are used to elucidate the behavior of liquid atoms near a solid boundary. Correlations between the surface wettability and spatial variations in liquid density and structure are identified. The self-diffusion coefficient tensor is predicted, revealing highly anisotropic and spatially varying mass transfer phenomena near the solid boundary. Th...

We find that both continuous and discontinuous hexatic-liquid transitions can happen in the melting of two-dimensional solids of soft-core disks. For three typical model systems, Hertzian, harmonic, and Gaussian-core models, we observe the same scenarios. These systems exhibit reentrant crystallization (melting) with a maximum melting temperature T_{m} happening at a crossover density ρ_{m}. Th...

Twenty years ago Poole et al. suggested that the anomalous properties of supercooled water may be caused by a critical point that terminates a line of liquid-liquid separation of lower-density and higher-density water. Here we present a thermodynamic model based on this hypothesis, which describes all available experimental data for supercooled water with better quality and fewer adjustable par...

We have used a variational approach to calculate some thermodynamic properties of the quasi-one dimensional liquid 3He such as the energy, entropy, free energy, equation of state and heat capacity at finite temperature. We have employed the Lennard-Jones potential as the inter-atomic interaction. We have seen that the total energy increases by increasing both temperature and density....