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Articles you may be interested inBrownian cluster dynamics with short range patchy interactions: Its application to polymers and step-growth polymerization J. Chem. Phys. 141, 024904 (2014); 10.1063/1.4886585 Brownian dynamics simulations of ionic current through an open channel AIP Conf.The method of molecular dynamics is applied to a solvent-averaged model of electrolyte solutions, described by a generalized Langevin equation. For Brownian motion without solute-solute interactions, we recover the characteristic features of an infinitely dilute solution. For interacting brownons, the results exhibit a noticeable dependence of the calculated self-diffusion coefficients on the influence of the Coulomb forces. The model system exhibits ion association when the Coulomb forces are made strong enough.

The thermodynamic properties of solutions of lanthanum or gadolinium chlorides in mixed molten LiCl-KCl were determined by electromagnetic force (emf) measurements of LaCl 3 or GdCl 3 formation cells. The temperature dependence of the emf between 380 and 590ЊC was used to calculate the Gibbs energy and the enthalpy of formation of dissolved LaCl 3 or GdCl 3 . The electrode processes of La(III) and Gd(III) reduced on a tungsten electrode were investigated by cyclic voltammetry and chronopotentiometry.

A new method was proposed for the preparation of carbon powders based on the electrochemical reduction of a fused eutectic mixture of lithium-sodium-potassium carbonates at 450°C. Transmission electron microscopy observations have revealed the presence of three forms of carbon in the powder samples depending on the deposition potential values: amorphous carbon, graphite, and fibers. The presence of graphite and amorphous carbon was confirmed by X-ray diffraction measurements. The d002 values were rather constant whatever the sample and close to 0.34 nm. Moreover, surface analyses by X-ray photoelectron spectroscopy revealed the presence of nearly metallic and ionic lithium belonging to lithium oxides. The specific areas were measured by the Brunauer-Emmett-Teller (BET) method. Whatever the deposit potential values, the total BET specific surface area is much higher than that corresponding to external one because of the pore walls contribution. It has been shown that, for carbon powder dried at 400°C under vacuum, the specific surface area decreased as the deposition potential became more cathodic: from about 850 m2 g−1 at −2.4 V vs. CO2­O2 to about 500 m2 g−1 at −6.0 V vs. CO2­O2. With increasing negative values of the potential, the nucleation and the growth of carbon competes with the formation of nearly metallic lithium and/or lithium oxides. The presence of the latter induces the closure of some nanopores. © 2002 The Electrochemical Society. All rights reserved.