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Registration Number

0215U004411, 0113U001530 , R & D reports

Title

Polyoxometalates of elements of V and VI groups in solutions, solid phase and medical compositions with hydroxyapatite

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Head

Rozantsev Georgy Mihailovich, Доктор хімічних наук

Registration Date

01-04-2015

Organization

Donetsk National University

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The formation and transformation processes of isopolytungstates in the system Na2WO4 - HCl - NaCl - DMF - H2O with different dimethylformamide (DMF) concentration have been studied by means of single-point pH-potentiometric titration and the subsequent modeling of the equilibria processes. The modeling of equilibria processes resulted in data necessary to synthesize a novel barium decatungstate, [Ba(H2O)2(C3H7NO)3]2[W10O32]?(C3H7NO)2. Synthesized salt was characterized by elemental and EDX spectral analysis, SEM, FTIR spectroscopy, thermal analysis, single-crystal X-ray diffraction analysis in solid state, and by UV-Vis. spectroscopy in solution. Conditions necessary for the formation of potassium-nickel paratungstate B K6Ni2[W12O40(OH)2]?22H2O (1) and potassium-nickel heteropoly hexatungstonickelate (II) with Anderson type anion K3Ni0,5[Ni(OH)6W6O18]?12H2O (2) in Ni(NO3)2 ? K2WO4 ? HNO3 ? H2O solution, acidified up to Z = ?(H+)/?(WO42-) = 1,00, were established. The synthesized salts 1 and 2 were examined using chemical analysis, X-ray single crystal analysis and FTIR spectroscopy. The compound 1 crystallizes in the triclinic system, space group , Mr = 3628.59, a = 10.617(3) ?, b = 11.818(2) ?, c = 13.454(3) ?, ? = 68.034(18)°, = 76.96(2)°, = 63.53(2)°, V = 1398.0(5); the compound 2 crystallizes in the monoclinic system, space group P21/n, Mr = 1914.71, a = 11.2586(3) ?, b = 11.4933(6) ?, c = 26.1158(15) ?, ? = 100.938(4)°, V = 3318.0(3) ?3. In the structure 1 paratungstate B anion [W12O40(OH)2]10- is centrosymmetric and occupies the center [[1/2,0,1/2]], while 2D layers consist of isopolyanion and potassium polyhedra KOn (n = 8, 10), forming the 3D structure through NiO6 octahedra. The structure 2 comprises Anderson type anions [Ni(OH)6W6O18]4-, cationic polyhedra NiO6, KO8 and uncoordinated H2O molecules. The surface morphology of sodium heteropoly hexatungstonickelate (ІІ) Na4[Ni(OH)6W6O18]?16H2O was investigated by scanning electron microscopy and the single-phase nature of the obtained sample was proven. Thermal transformations of Na4[Ni(OH)6W6O18]?16H2O was investigated by thermal analysis, XRD, and FTIR spectroscopy. It was found that destroying of the heteropoly anion with Anderson structure takes place after calcination of heteropoly salt above 250°C. The thermolysis products of Na4[Ni(OH)6W6O18]?16H2O are NiWO4, Na2W4O13, Na2W2O7. The conditions for the synthesis of novel Ce(III), Dy(III), and Ho(III)-containing salts with paratungstate B anion were determined. By the methods of chemical analysis and FTIR spectroscopy it was shown that Ce10[W12O40(OH)2]3?94H2O, Dy10[W12O40(OH)2]3·100H2O, Ho10[W12O40(OH)2]3·54H2O were precipitated from Na10[W12O40(OH)2]?27H2O solution after adding the stoichiometric amounts of lanthanide (III) salts. By FTIR spectroscopy, the isopoly anion is shown to belong to the paratungstate B structural type. It was found that single-phase product can not be obtained from acidified up to Z = ?(H+)/?(WO42-) = 1.17 aqueous solutions of Na2WO4. By the method of scanning electron microscopy it was shown that the grain size of synthesized salts is within the range of 300-750 nm. Homogeneity of the obtained paratungstate B salts was confirmed by the uniform contrast of the surface mode of backscattered electrons.

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Білоусова Катерина Євгенівна
Гумерова Надія Ісмагілівна
Заславська Людмила Володимирівна
Кузьміних Оксана Олександрівна
Мельник Наталя Олександрівна
Пилипенко Анастасія Олегівна
Пойманова Олена Юріївна
Радіо Сергій Вікторович
Хаустов Данило Володимирович

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2020-04-02