the molecular associations in the binary mixtures of (methanol/solvent), (ethanol/solvent) and (propanol/solvent) were studied using nmr, ftir and vle data at different temperatures. the activity coefficients as the most important quantities representing the mixture deviation form ideal behavior were evaluated by using various association models to express the physical and chemical contribution...

Spectral scanning was used to provide estimates of the leakage of the cyanogenic glucoside, dhurrin (p-hydroxy-[S]-mandelonitrile-beta-d-glucoside), and its metabolite, p-hydroxybenzaldehyde (p-HB), from young light-grown shoots of Atlas sorghum (Sorghum bicolor [L.] Moench) when these shoots were immersed in water, toluene, chloroform or mixtures of water and toluene or water and chloroform. M...

The solubility of satranidazole in several water-N,N-dimethylformamide mixtures was analysed in terms of solute-solvent interactions and data were treated on the basis of extended Hildebrand solubility approach. The solubility profile of satranidazole in water-N,N-dimethylformamide mixtures shows a curve with a solubility maxima well above the ideal solubility of drug. This is attributed to sol...

The unambiguous identification and quantification of hazardous materials is of increasing importance in many sectors such as waste disposal, pharmaceutical manufacturing, and environmental protection. One particular problem in waste disposal and chemical manufacturing is the identification of solvents into chlorinated or non-chlorinated. In this work we have used Raman spectroscopy as the basis...

Experimental solubilities of acetaminophen and ibuprofen in polyethylene glycol 600-water, ethanol-polyethylene glycol 600, and polyethylene glycol 600-water-ethanol mixtures at 25 degrees Celsius are reported. The solubilities of drugs in the presence of ethanol and polyethylene glycol 600 were increased. The Jouyban-Acree model was used to fit the solubility data of each drug in the binary mi...

Physico-chemical properties of liquid mixtures in general display large deviations from linear behaviour, arising out of complex specific and non-specific intermolecular interactions. The polarity of liquid mixtures displaying large positive and negative deviations can be minimized and linear mixing can be achieved in liquids using a pseudo-solvent methodology. The work described herein is desi...

We applied H and C NMR spectroscopy to investigate a phase transition and a cononsolvency effect of uncharged poly(N-isopropylmethacrylamide) (PIPMAm) and negatively charged PIPMAm copolymers in water/ethanol (D2O/EtOH) mixtures. For this purpose several PIPMAm solutions with various volume mixture compositions of D2O/EtOH (100/0 5/95 vol.-%) were prepared; sodium methacrylate was used as an io...

1. Conductivity and u.v. and visible spectroscopic techniques were used to investigate the solution structure of the prosthetic group of the ferric haemoproteins (ferrihaem) in dimethyl sulphoxide, NN-dimethylacetamide, NN-dimethylformamide and sulpholane, and certain of their aqueous mixtures. 2. In neutral or acid dimethyl sulphoxide, chlorohaemin is monomeric and completely dissociated into ...

ABSTRACT The kinetics and mechanism of the aromatic nucleophilic substitution reactions of 2,6-bis(trifluoromethanesulfonyl)-4-nitroanisole with para-X-substituted anilines (X = OH, OMe, Me, H, F, I, Cl) were studied in MeOH-Me2SO mixtures and pure Me2SO at 25.0 °C. The second-order rate coefficients depend on the substitutent in aniline and give good Hammett and Brønsted correlations; a polar ...

Calixresorcinarenes have proved to be unique molecules for molecular recognition via hydrogen bonding, hydrophobic and ionic interactions with suitable substrates such as cations. The study of the interactions involved in the complexation of different cations with calixresorcinarenes in solvent mixtures is important for a better understanding of the mechanism of biological transport, molecular ...