Methode zur Bestimmung des Verzweigungrades in Polyäthylenimin

Colloid and Polymer Science -     

Physicochemical Aspects of Test Methods Based on the Formation of Poorly Soluble Compounds in a Planar System

Test methods with the determination of concentration by the length (area) of colored zones of rectangular indicator supports sealed with a polymer film and in contact with the test solution by a narrow end or through a hole in the film were considered from the standpoint of planar precipitation chromatography. Based on the equation of material balance, the functional relationship is obtained between the length (area) of the colored zone of the test strip and the concentration of the analyte. On the basis of this relationship, a binary test strip was proposed for improving the sensitivity of determination; the binary test strip consists of the analytical (indicator element) and pumping (multilayer filter paper) systems and makes it possible to decrease the detection limit by a factor of ten in comparison with conventional test strips.     

Charge transfer in carbon composites based on fullerenes and exfoliated graphite

Physics of the Solid State - Kinetic processes have been studied in composites based on fullerenes and exfoliated graphite at the initial proportions of components from 1: 16 to 16: 1 in mass. The...     

Migration of the mobile phase and zones of separated substances in flat-bed chromatography

It is proposed to extend the area of application of circular separation of substances in flat-bed chromatography by a wider use of its intermedial modifications. Equations for calculating the basic parameters of migration of the mobile phase and zones of separated substances are given. The known equations are shown to be particular cases of the ones proposed.     

Over-pressure TLC variant on a plate with an enclosed sorbent layer

An over-pressure TLC variant with an enclosed sorbent layer and forced flow of the mobile phase was suggested. A simple new type device for its realization was developed.Translated from Izvestiya Akademioi Nauk. Seriya Khimicheskaya, No. 3, pp.771–773, March, 1996.