The phase equilibria for the extraction of aromatics from petroleum naphtha reformats (with a boiling range of 338-403K) using a mixed solvent of 1-cyclohexyl-2-pyrrolidone (CHP) and triethylene glycol (TEG) have been correlated using the universal function-group activity coefficients model (UNIFAC) group contribution model. The interaction parameters of CHP and TEG with different hydrocarbon g...

The interaction between the solute and the solsent molecules play a crucial role in understanding the various molecular processes involved in chemistry and biochemistry, so in this work the potential energy of active site of azurin have been calculated in solvent by the Monte Carlo simulation. In this paper we present quantitative results of Monte Carlo calculations of potential energies of ...

The time scales and pathways of heme cooling in both reduced cytochrome c and oxidized cytochrome c following heme photoexcitation were studied using molecular dynamics simulation. Five different solvent models, including normal water, heavy water, normal glycerol, deuterated glycerol, and a nonpolar solvent, were used in the simulation. Single exponential decay of the excess kinetic energy of ...

Recent studies on the solvation of atomistic and nanoscale solutes indicate that a strong coupling exists between the hydrophobic, dispersion, and electrostatic contributions to the solvation free energy, a facet not considered in current implicit solvent models. We suggest a theoretical formalism which accounts for coupling by minimizing the Gibbs free energy of the solvent with respect to a s...

By an initial solvent screening of 18 solvents, 14 pure good solvents were selected for the crystallization of tolbutamide. Solid generation by the solvent-change method was carried out using the pure good solvents. Crystals were generated in only 10 of the 14 solvents. Different crystal forms of tolbutamide were obtained. Crystals were subjected to evaluation tests such as differential scannin...

Zataria multiflora Boiss is used in traditional folk remedies as antiseptic, analgesic, carminative, anthelmintic medication. The main components of Z. multiflora are phenolic compounds such as thymol and carvacrol. The aim of this study was developed a simple and rapid method for determination of the thymol in different extracts of Z. multiflora by HPLC method. The dried aerial parts of Z. mul...