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1.
The crystal structure of a complex of pyrazinecarbohydroxamic acid (PHA) with Mo(VI) has been studied by X-ray diffraction analysis. The PHA molecule enters the complex composition as the enole tautomeric form. The branched intermolecular bonds form a strong three-dimensional framework with cavities filled with water molecules.  相似文献   
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An effect of modifiers on extraction of cobalt from chloride solutions was studied in an extraction mixture with trioctylamine. An optimal range of concentration of the most active modifier, actanone-2, was up to 50%. Excess concentrations of octanone-2 led to structural changes and reduced ketone extraction of cobalt.  相似文献   
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Perovskite-related oxide Tm x Cu3V4O12 (space group Im \(\bar 3\), Z = 2, a = 7.262?7.273 Å) with vacancies in the cationic sublattice has been prepared for the first time under barothermal conditions (p = 7.0?9.0 GPa, T = 900?1100°C). Electric resistivity (10–300 K) and magnetic susceptibility (0–300 K) were studied as a function of temperature. Tm x Cu3V4O12 is shown to have a metallic conductivity and paramagnetism.  相似文献   
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AMn3V4O12 (A = Ca, Ce, and Sm) compounds with a perovskite structure are synthesized at high pressures and temperatures. The crystalline structure of these compounds (space group \(Im\bar 3\)Z = 2) is determined via X-ray analysis. If ions in the A sublattice are changed in the order Ca2+–Sm3+–Ce3+, the valence is redistributed from Ca2+Mn32+V44+O12 to Sm3+Mn32+V43.75+O12, and to Ce3+Mn32+V43.75+O12. The temperature dependences of the electrical resistivity are studied.  相似文献   
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Binary complex salts, [Co(En)3][Fe(CN)6] · 2H2O and [Co(En)3]4[Fe(CN)6]3 · 15H2O, are synthesized. The properties of the salts and their thermolysis in air, dihydrogen, and argon are studied. Oxides of the central ions of the binary complex salts are found to be the thermolysis products in an oxidative atmosphere. Solid solutions (intermetallic compounds) CoFe are the thermolysis products in the reductive atmosphere, whereas intermetallides containing considerable amounts of C and N and an impurity of Co and Fe oxides are the thermolysis products in an inert atmosphere. Gaseous thermolysis products in dihydrogen and argon are NH3, hydrocarbons, and ethylenediamine.  相似文献   
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Methods of crystal-optic, X-ray phase, chemical, and IR spectroscopic analyses were used to study the interaction of sphene and fluorapatite concentrates with dilute mineral acid solutions. The conditions under which the sphene concentrate can be purified to remove admixtures of phosphorus-containing compounds were found.  相似文献   
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