Properties of Mixed Aqueous Solutions of Polyethylene Oxide and Carboxymethyl Cellulose with Different Degrees of Ionization and of Composite Films Prepared from Them

Russian Journal of Applied Chemistry - Rheological properties of mixtures of dilute and moderately concentrated aqueous solutions of carboxymethyl cellulose with various degrees of ionization and...     

Synthesis and Antioxidant Activity Evaluation of Novel 5,7-dimethyl-3H-Thiazolo[4,5-B]Pyridines

Abstract

5,7-Dimethyl-3H-thiazolo[4,5-b]pyridine-2-one was obtained under the reaction of 4-iminothiazolidin-2-one with acetylacetone. Further structural modifications include the introduction of diversity at the N³ and C⁶ positions. The antioxidant activity of the synthesized compounds was evaluated in vitro by the method of scavenging effect on 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals.

[Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the following free supplemental files: Additional figures]     

Endotypes of partial equivalence relations

We classify all partial equivalence relations according to their endotype with respect to endotopisms and compute the cardinalities of endotopism semigroups (strong endotopism monoids, autotopism groups) of partial equivalence relations on a finite set.

     

The study of quenching efficiency of three-phase foams formed in flotation of phosphate rock

The effect of inorganic electrolytes on the foaming and stabilizing activity of three-phase foams formed in flotation of phosphate rock was determined. It was shown that the effect of inorganic salts on the above properties of the foams depends on both the concentration of the salts and their nature.     

Method for analysis of the porous structure of potassium chloride grains

Method for determining the total porosity of potassium chloride grains is suggested. The method includes pycnometric measurements of the true and apparent densities of the grains, with kerosene used as a pycnometric liquid.     

Study of the interfacial tension in model and technical emulsions in the presence of surfactants and inorganic electrolytes

Interfacial tension in the oil/water system in the presence of various ionic surfactants and inorganic electrolytes was studied. Special features of the effect of the surfactant and oil phase natures, of the structure of their molecules, and also of the electrolytes containing ions with various radii, valences, and hydratabilities on the value of the interfacial tension were studied. The criteria and conditions of obtaining model emulsions based on paraffin hydrocarbons and technical emulsions based on vegetable oils were determined.