the complexation reactions between methylthymol blue (mtb) and co2+, ni2+, cu2+, zn2+ and pb2+ ions have been studied in different water-methanol mixtures at ph 4.45 and 25 °c by a spectrophotometric technique. the stepwise stability constants of the resulting 1:1 and 2:1 (metal ion to ligand) complexes were determined from the absorbance-mole ratio data. it was found that the overall stability...

OBJECTIVE This study aims to compare liver function indices (aspartate aminotransferase [AST], alanine aminotransferase [ALT], and gamma glutamyl transferase [GGT]) among males who work with lead, organic solvents, or both lead and organic solvents, under the permissible exposure limit (PEL). METHODS A total of 593 (out of 2,218) male workers who agreed to share their personal health informat...

the solubility of kno3 in the mixed solvent (water 85%+methanol 15%) were determined by using solvent evaporating method at different temperatures (25, 30, 40, 50, 60 ;c). in addition the equilibrium constant of ion pair formation, kip, for k+no3 – ion-pair on the basis of fuoss contact ion pair model was calculated. upon choosing the extended debye-hückel model for estimating the mean activity...

in this study, the ion association phenomenon in the saturated solution of kcl in the mixed solvent(methanol+water) was studied. the solubility of this compound in the mixed solvent (methanol+water by value percent of methanol = 60%), and in the presence of various molarities of nano3 wasdetermined by the solvent evaporation method at 25.0°c. the results enable us to estimate the valueof thermo...

A general model has been developed for calculating the static dielectric constant of mixed-solvent electrolyte solutions. For mixtures of solvents without electrolyte components, the model is based on an empirical modification of the Kirkwood theory for multicomponent systems. For systems containing electrolytes, the model takes into account the effects of ions and ion pairs and, therefore, it ...

Soret coefficients of the ternary system of poly(ethylene oxide) in mixed water/ethanol solvent were measured over a wide solvent composition range by means of thermal diffusion forced Rayleigh scattering. The Soret coefficient S(T) of the polymer was found to change sign as the water content of the solvent increases with the sign change taking place at a water mass fraction of 0.83 at a temper...

A comprehensive model has been developed for calculating the surface tension of aqueous, nonaqueous, and mixedsolvent electrolyte systems ranging from dilute solutions to fused salts. Themodel consists of a correlation for computing the surface tension of solvent mixtures and an expression for the effect of electrolyte concentration. The dependence of surface tension on electrolyte concentratio...

the equilibrium constant of adduct formation between some triorganotin chloride of the type r3sncl (r=c6h5, p-ch3c6h4, n-ch3)ch2)3, c6h5-ch2 and lewis bases cl¯, br¯, and i¯, were measured in 50% v/v ethanol-water solvent spectrophotometrically. the average equilibrium constant values for the systems studied shows the following acceptor trend of tin(iv) in the triorganotin chlorides: p-tolyl > ...

The mutual entropic depletion force felt by two solute "big" hard spheres immersed in a binary mixture solvent of nonadditive "small" hard spheres is calculated as a function of the surface-to-surface distance by means of canonical Monte Carlo simulations and through a recently proposed rational-function approximation [R. Fantoni and A. Santos, Phys. Rev. E 84, 041201 (2011)]. Four representati...