Complexation of magnesium and calcium ions with heparin

The acid-base properties of unfractionated heparin (H₄L) and the complexation of biometal ions (Mg²⁺ and Ca²⁺) with heparin in aqueous solutions have been studied by pH titration, using mathematical modeling methods in data processing. The heparin concentration is taken to be equal to the concentration of heparin disaccharide units. The formation constants of the protonated heparin species H_iL (i = 1, 2) have been estimated. The most abundant Mg²⁺-heparin and Ca²⁺-heparin complex species have been identified, and their formation constants have been estimated.     

Physicochemical investigation of the ternary system KF-H2O2-H2O

Conclusions An investigation of the fusibility in the system KF-H₂O₂-H₂O confirmed the existence of KF · H₂O₂ and demonstrated the formation of a new compound, KF · 2H₂O₂, which exists in the system in the interval from –70 to 20° in the region of high hydrogen peroxide concentrations.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 491–494, March, 1973.     

Intensification of water purification by reagent method

On the example of real dispersal system (effluent) are tested coagulants and flocculants of different nature. A decrease in the content of harmful impurities after working up of the system by the reagents is established by the methods of physicochemical analysis.     

On the unsolvability of the conjugacy problem for subgroups of the groupR 5 of pure braids

The main objective of the paper is the proof of the unsolvability of the conjugacy problem for subgroups of the pure braid groupR ₅. Translated fromMatematicheskie Zametki, Vol. 65, No. 1, pp. 15–22, January, 1999.     

Dehydrogenation of hydrocarbons over alumina-chromia catalysts containing additions of certain metal oxides

Russian Chemical Bulletin -