Finite temperature calculations for the bulk properties of strange star using a many-body approach

We have considered a hot strange star matter, just after the collapse of a supernova, as a composition of strange, up and down quarks to calculate the bulk properties of this system at finite temperature with the density dependent bag constant. To parameterize the density dependent bag constant, we use our results for the lowest order constrained variational (LOCV) calculations of asymmetric nuclear matter. Our calculations for the structure properties of the strange star at different temperatures indicate that its maximum mass decreases by increasing the temperature. We have also compared our results with those of a fixed value of the bag constant. It can be seen that the density dependent bag constant leads to higher values of the maximum mass and radius for the strange star.Comment: 21 pages, 2 tables, 12 figures Astrophys. (2011) accepte

Isotherm and kinetics of As(III) uptake from aqueous solution by Cinnamomum zeylanicum

Cinnamon-bark (Cinnamomum zeylanicum) powder (CP) was investigated to evaluate the As(III) biosorption capability from aqueous solution. Biosorption behavior of As(III) was studied by batch column experiments. The adsorption phenomenon were analyzed with various experimental variables such as solution pH, sorbent amount, agitation speed, initial As(III) concentration and temperature. Maximum sorption was occurred at pH 5.0 while the equilibrium was established in 8 h. Langmuir and Freundlich isotherm models were employed for fitting the experimental data. The maximum sorption capacity of CP was observed to be 36.311 μg g-1. The biosorption kinetics was speculated to follow pseudo-first-order kinetic model (R2 =0.998) with the sorption rate of 15.340×10-3 min-1 for the initial As(III) concentration of 500 μg L-1. The biosorbent material was characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The activation energy (Ea) and heat of biosorption (H) were calculated to be 17.780 and 30.724 kJ mol-1 respectively. Thermodynamic parameters were evaluated which revealed the spontaneous nature of biosorption on CP accompanied with the physical activated process. The break through characteristics of C. zeylanicum packed column was also investigated by small scale column tests (SSCT)

Spin-spin correlation effect on the thermodynamic properties of the polarized liquid 3 He at finite temperature

We have used the lowest order constrained variational (LOCV) method to calculate some thermodynamic properties of the polarized liquid 3He at finite temperature with the spin-dependent correlation function. For each value of the temperature and density we have shown that the main contribution to the potential energy comes from the spin-triplet state. For the polarized liquid 3He, we have seen that the differences between the thermodynamic properties of the spin-dependent and the spin-independent cases decrease by increasing both polarization and temperature. For all relevant temperatures and densities, our results do not show any ferromagnetic phase transition