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Information × Registration Number 0223U001689, 0122U000762 , R & D reports Title Compounds of d- and f-metals with polyoxometalate anions and prediction of interaction in complex oxide systems popup.stage_title Head Rozantsev Heorhii M., Доктор хімічних наук Registration Date 01-02-2023 Organization Vasyl' Stus Donetsk National University popup.description2 The conditions for the synthesis of tungsten(IV) compounds with copper(II) cations from acidified aqueous sodium orthotungstate solutions at different acidity values (Z=1.08-1.42) have been established. According to the developed procedures for synthesis, sodium-copper(II) double paratungstates B Na2Cu4[W12O40(ОН)2]·22Н2О, Na4Cu3[W12O40(ОН)2]·28Н2О, Na6Cu2[W12O40(ОН)2]·31Н2О were obtained. The composition of compounds was established by chemical elemental analysis, FTIR and SEM. The belonging of the salts to paratungstates B was proved on the basis of the results of IR spectroscopy in the area of oscillations of the tungsten-oxygen framework. Na6Cu2[W12O40(ОН)2]·31Н2О showed high antimicrobial activity against Escherichia coli ATCC 25922. As part of antibacterial studies, the minimum inhibitory concentration of MIC = 500 µg∙ml–1 and the minimum bactericidal concentration of MBK = 700 µg∙ml–1 were determined. The results of the study of interactions in an aqueous solution of Cd2+ – WO42– – H+(Z = 1.00) – H2O by the method of pН-potentiometric titration and mathematical modeling by the CLINP2.1 program are given. Among the applied models, the one that best described the experiment, which consisted of ionic pairs [CdOH+, W12O40(OH)2]9-, [Cd2+, W12O40(OH)2]8- [Cd2+, HW12O40(OH)2]7-, [ Cd2+, H2W12O40(OH)2]6-, [Cd2+, W12O38(OH)2]4-, [Cd2+, HW12O38(OH)2]3-. The logarithms of the concentration constants of the formation of ion pairs, which were stored during the simulation, were used to calculate the logarithms of the thermodynamic constants according to the Pitzep method. Double sodium-cadmium(II) paratungstate B Na6Cd2[W12O40(OH)2]·25H2O was obtained, which was investigated by the methods of chemical elemental analysis, sSEM, and FTIR spectroscopy. The conditions for the formation of La(III)-containing polyoxotungstates in solutions of the system Na2WO4 – HNO3 – La(NO3)3 – H2O/organic solvent (acetone, acetonitrile, ethanol) acidified to Z=0.80 were established. Product Description popup.authors Baumer Vyacheslav M Velichko Maryna P. Get'man Evgen I. Duvanova Ella S. Zubov Eduard Ye. Knyzhnyk Ivan A. Kordysh Oleksii M. Mariichak Oleksandra Yu. Radio Serhii V. popup.nrat_date 2023-02-01 Close