this study has been done to survey of solvent system effect on extraction of grape seed extract and its antimicrobial properties. for this purpose, grape seed extracts were extracted with six different solvent systems. minimum bactericidal concentration (mbc) of extract on six spoilage and food-born pathogens was determined. the results indicated that mbc of different extracts have no significa...

two dimensional thin layer chromatography on polyamide sheets is a useful method for identification of pth-amino acids which have very close rf-values. the solvent systems described here are particularly effective and have an edge over other solvent systems used for the separation of pth-amino acids. the solvent systems provide a clear separation of all pth-amono acids except lle / leu in a rel...

a multiple-unit oral floating system was prepared using the emulsification-solvent diffusion method to prolong the gastric emptying time of theophylline. for this purpose, theophylline, ethyl cellulose and dibutyl phthalate were dissolved in an ethanol/dichloromethane mixture, added to 0.1 m hcl containing nacl (20%) or saturated theophylline and/or different concentrations of polysorbate 80 an...

This review incorporates a large number of chromatographic systems modified by the surfactants. A large number of solvent systems and stationary phases are summarized in this paper. Three different kinds of surfactants (anionic, cationic, and nonionic) are used as modifiers for stationary phases as well as solvent systems. Surfactants are used at all the three different concentration levels (be...

The concentrations of all components in the phases of aqueous two-phase polyethylene glycol-sodium sulfate system of a fixed composition with different concentrations of NaCl additive were determined. Solvatochromic solvent features of aqueous media in the phases of all the systems were characterized in terms of solvent dipolarity/polarizability, solvent hydrogen bond donor acidity and hydrogen...

Two dimensional thin layer chromatography on polyamide sheets is a useful method for identification of PTH-amino acids which have very close Rf-values. The solvent systems described here are particularly effective and have an edge over other solvent systems used for the separation of PTH-amino acids. The solvent systems provide a clear separation of all PTH-amono acids except lle / Leu in a...

isotactic poly (1-butene), ipbu-1, was synthesized by using a metallocene catalyst. the thermodynamic phase behavior of polymer–organic solvents systems is very important in every polymer application.  in this paper, the solid–liquid equilibrium of ipbu-1 with different organic solvents (1-heptyne, cyclo octane) was studied by a mathematical model. by considering the experiments temperature-mol...