Viscosity Of Binary Solutions Research Articles

Volumetric and viscometric properties of aqueous solutions of sodium amino acids at T = (293.15 to 333.15) K

The densities and viscosities of aqueous solutions of sodium glycinate, sodium l-alaninate, sodium l-valinate, sodium l-threoninate and sodium l-argininate were measured at T = (293.15 to 333.15) K under the atmospheric pressure. The effects of temperature and concentration on the densities and viscosities of binary solutions were investigated. The volumetric and viscometric properties such as the apparent molar volume (Vφ), the limiting partial molar volume (Vφ0), the viscosity B-coefficient (B) and the activation energy for viscous flow (Ea) were calculated by the experimental density and viscosity data and analyzed based on the molecular structure and intermolecular interaction. Moreover, the group contribution method was utilized to study the limiting partial molar volume (Vφ0), and the contributions of the end group (-NH2,-COONa), CH- group, CH2- group, CH3- group, OH- group and CNHNHNH2- group to the limiting partial molar volume (Vφ0) were obtained. The results show that all these groups have positive contributions to the limiting partial molar volume (Vφ0).

Development of a locally anesthetizing wound dressing based on eudragit RS ultrathin fibers

It was demonstrated that a locally anesthesizing dressing material based on the amine-containing copolymer Eudragit RS could be prepared by electrospinning. The dependences of the electrical conductivity and dynamic viscosity of binary solutions of Eudragit RS and lidocaine in EtOH on concentration were established. The kinetics of lidocaine release from Eudragit RS fibers into an aqueous medium were determined. The influence of copolymer fiber diameter and content of local anesthetic lidocaine in it on the duration of the release was found. It was shown that the obtained locally anesthesizing dressing material based on Eudragit RS provided timed-release of the drug.

Prediction of viscosity of mixed electrolyte solutions based on the Eyring's absolute rate theory and the equations of Patwardhan and Kumar

The mixing behavior of viscosities of electrolyte solutions at constant ionic strength has been studied for the first time using the Eyring's absolute rate theory and the equations of Patwardhan and Kumar. Coupling of the Eyring's theory with the equations of Patwardhan and Kumar yields simple mixing behavior of viscosities of electrolyte solutions at constant ionic strength, and thus permits the establishment of new simple equations for viscosity, which can provide predictions for mixed solutions using only information on the single solute solutions. The new equations have been compared with the experimental results for fifteen systems and the existing equations reported in literature. The present equations generally give the best predictions and the agreement with experimental results is in general quite good. The effect of different contributions accompanying the mixing process on the predicted results has been studied. The viscosities of the mixed electrolyte solutions can be well predicted only by using the additive contribution from the viscosities of binary solutions at constant ionic strength. The addition of the mixing term in this simple additive equation yields better predictions. The inclusion of the density term has little effect on the predicted results.

Prediction of viscosity of mixed electrolyte solutions based on the Eyring's absolute rate theory and the semi-ideal hydration model

The mixing behavior of viscosities of electrolyte solutions under isopiestic equilibrium has been studied for the first time using the Eyring's absolute rate theory and the semi-ideal hydration model. The concentration dependence of the change in molar free energy of activation for flow has been formulated and discussed based on the concept of average hydration number and the structure-making or structure-breaking nature of the ion species. Coupling of the Erying's theory and the semi-ideal hydration model yields very simple mixing behavior of viscosities of electrolyte solutions under isopiestic conditions and thus yields new simple equations for viscosity, which can provide predictions for mixed solutions using only information on the single solute solutions. The new equations have been tested by comparisons with the experimental results for 15 systems and the existing equations reported in literature. The present equations improve the predictions considerably and the agreement with experimental results is in general quite good. The effect of different contributions accompanying the mixing process on the predicted results has been studied. The viscosities of the mixed electrolyte solutions can be well predicted only by using the additive contribution from the viscosities of binary solutions under isopiestic condition. The addition of the mixing term in this simple additive equation yields better predictions for mixed solutions mainly consisting of the structure-making ions. The inclusion of the density term has little effect on the predicted results.

Viscosity of the Systems Methanol- n -Octane and Ethanol- n -Octane

The kinematic viscosity of binary solutions methanol-n-octane at 293.15-313.15 K and ethanol-n-octane at 263.15-298.15 K in the miscibility range (low concentrations of n-octane) was measured. In the methanol-octane system, the viscosity shows an abnormal behavior. As shown by molecular-dynamic calculations, this effect is due to formation of a specific type of associates, which results in a decrease in the molecular mobility as the n-octane concentration is increased (up to the phase separation point).

Densities and viscosities of binary solutions containing butylamine, benzylamine, and water

Densities and viscosities of the binary mixtures compared of butylamine, benzylamine, and water are measured at 303.15, 313.15, and 323.15 K over the entire molar fraction range. The excess volume and viscosity deviation are calculated from the experimental data and correlated by a Redlich-Kister-type equation in terms of molar fraction. McAllister's models are also used to correlate the kinematic viscosities

Viscosity of binary solutions of polar liquids

The viscosity of mixtures of water with a number of organic liquids and of some mixtures of two organics has been analysed in terms of its deviation from "ideality", expressed as ln H = ln η − (x1 ln η1 + x2 ln η2). For most of the systems the quantity ln H is a single-valued and linear, or nearly linear, function of the product y1y2, where[Formula: see text]representing mole fractions (with κ = 0), or volume fractions (κ = 1), or various compromises (0 < κ < 1). Neither extreme, nor any single compromise, expresses the behaviour of all the systems. A linear relation between 1/H and the relative excess volume, suggested on the basis of the free-volume theory of fluidity, is shown to represent approximately the behaviour of the mixtures of two organic liquids. It fails with the water–organic mixtures.

Viscosities of binary solutions of non-electrolytes

Viscosities and molar volumes of binary solutions,viz., Toluene-Nitrobenzene, Toluene-Bromobenzene, Toluene-Cyclohexanone, Cyclohexane-Cyclohexanone, Cyclohexane-Nitrobenzene, Cyclohexane-Acetic acid, Cyclohexane-Propionic acid and Cyclohexane-Butyric acid have been measured. The experimental results have been discussed in terms of viscosity-composition relations developed for binary solutions by Grunberg and Nissan and Katti and Chaudhri.