Herein we demonstrate the formation of new stimuli-responsive aqueous biphasic systems (ABS), able to respond simultaneously to temperature and pH, or just to one stimulus, therefore allowing the design of more sustainable separation processes. This dual behavior is achieved with ABS formed by mono- or dicationic protic ionic liquids as phase-forming components, being defined by the ionic liquid cation chemical structure or its basicity. While ABS comprising monocationic ionic liquids only respond to the effect of temperature, systems comprising dicationic ionic liquids are simultaneously affected by both temperature and pH variations.
View Article and Find Full Text PDFThe densities and viscosities of synephrine hydrochloride and octopamine hydrochloride aqueous solutions were determined. Apparent molar volumes, apparent molar volume at infinite dilution, viscosity B-coefficients and hydration number were calculated, and it was found that synephrine hydrochloride acts as a better structure maker than octopamine hydrochloride in aqueous solutions. The densities of the investigated salts were measured in aqueous d-fructose solutions, and the corresponding apparent molar volumes of transfer at infinite dilution were determined.
View Article and Find Full Text PDFThe purpose of this work is to promote and facilitate forensic profiling and chemical analysis of illicit drug samples in order to determine their origin, methods of production and transfer through the country. The article is based on the gas chromatography analysis of heroin samples seized from three different locations in Serbia. Chemometric approach with appropriate statistical tools (multiple-linear regression (MLR), hierarchical cluster analysis (HCA) and Wald-Wolfowitz run (WWR) test) were applied on chromatographic data of heroin samples in order to correlate and examine the geographic origin of seized heroin samples.
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