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1. The ultraviolet spectroscopy method was used to study the weak intermolecular reactions in solutions of low-molecular organic compounds. 2. A comparison was made of the selectivity of the reaction of organic ions with polyelectrolytes and of the spectroscopic characteristics of the corresponding low-molecular analogs. 3. A high selectivity in organic ion-polyelectrolyte systems was compared with the greatest shift in the maximum of the UV absorption band of the corresponding model compound.

1. The thermodynamic functions characterizing the intermolecular interaction were determined according to the temperature dependence of the selectivity of the binding in the system of organic ion of hydroxytetracycline (HTC) and polyelectrolyte. 2. The HTC-polyelectrolyte interaction is intensified by the transition from soluble to cross-linked polyelectrolytes. 3. The entropy and enthalpy components of the free energy change for the HTC-polyelectrolyte system are correlated with the increase in the amount of the cross-linking agent and pass through a maximum at 0.5% DVB. 4. An interpretation is given for the thermodynamic data on the basis of the assumption of supplementary (in addition to coulombic) interaction of HTC with polyelectrolytes.

1. In the case of ion exchange on polyelectrolytes, an increase and a decrease in the selectivity of sorption are observed, independent of the solvent and explained by cooperative interaction of the chains of the polymer through “ties” the role of which is played by molecules of the sorbed substance. 2. A mechanism of sorption with isotherms possessing a maximum is proposed for ion exchange sorption on linear and cross-linked synthetic polyelectrolytes and for molecular adsorption. The isotherms of sorption with a maximum are observed when the state of the solution changes with increasing concentration of the substance to be sorbed and a consequent drop in the selectivity of the interaction and sorption capacity.

1. A study was made of the infrared absorption spectra of some amino acids, both in the dry form and as solutions in heavy water at various pH. 2. The absorption band in the 1728–1740 cm−1 region and the band in the 1593–1612 cm−1 region are determined respectively by the non-ionized -COOH and the ionized -COO− of the carboxyl group of the amino acids. 3. In the sorbed state the amino acids are found as the cation+NH3-R-COOH, independent of the pH of the solution from which the sorption was made

1. On the example of the partially sulfonated polystyrene cationites it was shown that nonionic reaction of the hydrocarbon chains of the polymer among themselves, i.e., reaction of the sorbent-sorbent type, can arise. 2. The interrelation between the sorption selectivity of the organic HTC, C, and TEBA ions and the value of the total exchange capacity of some sulfo cationites was ascertained, which indicates that interchain reaction in the cationites plays an important role in the total energy of the process for the selective sorption of organic ions.

1. The organic ions of antibiotics (tetracycline, hydroxytetracycline, and chlorotetracycline) in aqueous acidic solution form associates (at concentrations above 10−4 M), the size of which, like surfactants, reaches tens of molecules. The associates, like the surfactant micelles, are probably formed as a consequence of the hydrophobic interaction between molecules. 2. The viscosity of the solutions decreases during the formation of an organic ion-polyelectrolyte complex in the case of associated hydroxytetracycline and cetylpyridinium bromide ions and changes little for unassociated triethylbenzylammonium ions. This is explained by the interaction of ions among themselves (associations) in the polymer-bonded state.

Sixty five patients with pulmonary tuberculosis subjected to extensive and traumatic surgical interventions were investigated. Metabolic alkalosis to the end of the 1st--2d postoperative day would develop in patients, who showed acid-base balance disorders toward acid aspect during the operation. In the mechanism of development of a grave decompensated postoperative metabolic alkalosis the role of a trigger factor is played by a massive intraoperative blood loss with marked hemodynamic disturbances in the immediate postoperative period.

1. The kinetic curves and the sorption isotherms of insulin on a macroporous polyelectrolyte were obtained. 2. In the sorption of insulin the first monolayer is filled rapidly at the start, and then slower sorption occurs in the subsequent layers.

1. The diffusion coefficient of insulin in macroporous polyelectrolytes is two orders of magnitude higher than in gel polyelectrolytes, which indicates that the insulin is sorbed only on the surface of the pores (or channels), in contrast to the low-molecular organic ions of the ATS, which are sorbed throughout the entire volume of the macroporous ionite granule. 2. The complex of insulin with the gel ionite is more stable than the complex of insulin with the macroporous polyelectrolyte, probably due to additional intermolecular reaction.