The acidity constants of 4-(2-pyridylazo)resorcinol (PAR, Scheme 1) in binary mixtures of methanol–water at 25 ◦C and an ionic strength of 0.1 M have been determined spectrophotometrically. DATa ANalysis (DATAN) program applied for determination of acidity constants. As percent of methanol increases in solvent mixtures the pKa constants also increased. There is linear relationship between acidi...

In this work, the solubilities of pharmaceutical cocrystals in solvent/anti-solvent systems were predicted using PC-SAFT in order to increase the efficiency of cocrystal formation processes. Modeling results and experimental data were compared for the cocrystal system nicotinamide/succinic acid (2:1) in the solvent/anti-solvent mixtures ethanol/water, ethanol/acetonitrile and ethanol/ethyl acet...

Crystallization of the drug entacapone from binary solvent mixtures was monitored in situ using a Raman optical probe. The recorded Raman spectra and statistical analysis, which included the principal components method and indirect hard modeling made it possible to estimate the starting point of crystallization, to assess crystallization temperatures and to provide information on the polymorphi...

Solvent effects on 2,6-dichloro-4-(2,4,6-triphenyl-pyridinium-1-yl)phenolate [ET (33) dye] and 7diethylamino-3,4-benzophenoxazine-2-one (Nile Red) in binary mixtures of organic solvents (acetone, acetonitrile, propylene carbonate, methanol and ethane-1,2-diol) with 1,3-dialkyl imidazoliumbased ionic liquids were studied by UV-visible spectroscopy. Highly nonlinear behaviour of mixtures of alcoh...

Anion recognition of two flexible diols in different solvents and binary mixtures were examined. Binding constants (K) in CD3CN and CDCl3 are surprisingly similar, and CD3CN-solvent mixtures led to reduced values of K that are smaller than in either pure solvent. A surprising U-shaped dependence is observed.

Low volatility solvent/non-solvent mixtures were utilized to engineer the structure of poly(3-alkylthiophene) (P3AT) organogels. The ratio of solvent to poor-solvent was manipulated to systematically control the kinetics of self-assembly. Specific solvent mixtures were utilized to produce similar gelation kinetics with polymers of differing alkyl chain length. Simultaneous small angle neutron s...

The paper presents results of the shear viscosity measurements performed on diluted binary mixtures of mesogenic solvent n-hexylcyanobiphenyl (C6H13PhPhC≡N, 6CB) and two non-mesogenic admixtures: (i) n-heptylcyanophenyl (C7H15PhC≡N, 7CP), composed of the molecules of the same polarity as the solvent molecules but of a slightly shorter length, and (ii) 4-n-propylcyclohexyl-4’-n-pentylphenyl (C3H...

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 ...

Temperature and pressure were shown to vary significantly with solvent mixing, showing maxima at different solvent ratios. Acetonitrile/water mixing resulted in temperature reduction of solutions whereas methanol/water mixing caused temperature increases. On the other hand, maximum recorded chromatographic pressure of acetonitrile:water mixtures occurred at a solvent ratio of 1:6 compared with ...