We present the results of extensive computer simulations performed on solutions of monodisperse charged rod-like polyelectrolytes in the presence of trivalent counterions. To overcome energy barriers we used a combination of parallel tempering and hybrid Monte Carlo techniques. Our results show that for small values of the electrostatic interaction the solution mostly consists of dispersed sing...

Consider an equilibrium reaction aA+ bB ⇀↽ cC+ dD We do not specify any phases, as we will treat the reaction generally using activities. An equilibrium reaction is one that can proceed in both directions, as indicated by the ⇀↽ symbol replacing the usual −→ in the chemical equation. Recall that the molar free energy ∆Ḡj for compound j in the reaction in terms of its activity aj as ∆Ḡ = ∆Ḡ◦ +RT...

Two phenomenological approaches are currently used in the study of the vitreous state. One is based on the concept of fictive temperature introduced by Tool [J. Res. Natl. Bur. Stand. 34, 199 (1945)] and recently revisited by Nieuwenhuizen [Phys. Rev. Lett. 80, 5580 (1998)]. The other is based on the thermodynamics of irreversible processes initiated by De Donder at the beginning of the last ce...

The need for polymers for high-end applications, coupled with the desire to mimic nature's macromolecular machinery fuels the development of innovative synthetic strategies every year. The recently acquired macromolecular-synthetic tools increase the precision and enable the synthesis of polymers with high control and low dispersity. However, regardless of the specificity, the polymerization be...

Thermodynamic analysis of the cracking of hexane has been conducted by the Gibbs free energy minimization method and second law analysis of overall reactions. By-products have been divided into three groups of methane, alkynes and aromatics and their possible production paths have been discussed. Effect of operating conditions such as temperature and steam-to-hexane ratio on the cracking perfor...

Thermodynamics has established in chemistry principally as a science determining possibility and direction of chemical transformations and giving conditions for their final, equilibrium state. Thermodynamics is usually thought to tell nothing about rates of these processes, their velocity of approaching equilibrium. Rates of chemical reactions belong to the domain of chemical kinetics. However,...

The knowledge of sorption processes of nonelectrolytes in solution by solid adsorbents implies the study of kinetics, equilibrium, and thermodynamic functions. However, quite frequently the equilibrium isotherms are studied by comparing them with those corresponding to the Giles et al. classification (1); these isotherms are also analyzed by fitting them to equations based on thermodynamic or k...

an ion imprinted polymer (iip) based on aniline-formaldehyde was synthesized and then modified with extra aniline as cross-linker in the presence and absence of sr (ii) as the template to produce ion imprinted poly(aniline-formaldehyde) (iipaf) and non imprinted poly(aniline-formaldehyde) (nipaf). the sorbent was characterized by fourier transform infrared spectroscopy and was used for solid ph...

in this study, the potential of biosorbent obtained from silk maze, was investigated for the batch biosorption of direct red 81 (dr 81) in aqueous solution. the effects of temperature, biosorbent amount, contact time, initial dye concentration and ultrasonic irradiation were also evaluated. furthermore, experimental equilibrium and kinetics data were fitted by langmuir and freundlich isotherms ...