Three different brands of Rose hip (Rosa canina L.) tea were extracted with water, ethanol (EtOH), methanol (MeOH), and aqueous mixtures (50%, v/v) by ultrasound-assisted extraction (UAE) and Soxhlet methods. Total phenolic content was determined according to the Folin-Ciocalteu method. The results were presented by means of the extract yields and total phenolic contents, expressed in gallic ac...

densities and excess molar volume of the binary and ternary mixtures formed by nbutylacetate+ 1-butanol + 1,2-butanediol were measured at (298.15, 303.15, and 308.15) k forthe liquid region and at ambient pressure (81.5) k pa , for the whole composition range. theexcess molar volumes,vme and excess partial molar volume vie ,were calculated fromexperimental densities.the excess molar volumes are...

a spectrophotometric method is used to determine the acidity constants of some derivatives of 9,10-anthraquinone in binary methanol-water mixtures at 25 °c. there is a linear inverse relationship between pka of all acids and the mole fraction of methanol in the mixed solvent. the influence of substituents in the molecular structure on the ionization constants is discussed.

Densities and excess molar volume of the binary and ternary mixtures formed by nbutylacetate+ 1-butanol + 1,2-butanediol were measured at (298.15, 303.15, and 308.15) K forthe liquid region and at ambient pressure (81.5) k Pa , for the whole composition range. Theexcess molar volumes,VmE and excess partial molar volume ViE ,were calculated fromexperimental densities.The excess molar volumes are...

A spectrophotometric method is used to determine the acidity constants of some derivatives of 9,10-anthraquinone in binary methanol-water mixtures at 25 °C. There is a linear inverse relationship between pKa of all acids and the mole fraction of methanol in the mixed solvent. The influence of substituents in the molecular structure on the ionization constants is discussed.