Helium defectoscopy of cerium gadolinium ceramics Ce0.8Gd0.2O1.9with a submicrocrystalline structure in the impurity disorder region

The concentration of impurity anion vacancies formed upon the dissociation of gadolinium-vacancy complexes has been determined using helium defectoscopy of the cerium gadolinium ceramics Ce0.8Gd0.2O1.9with a submicrocrystalline structure in the temperature range T = 740-1123 K and at saturation pressures ranging from 0.05 to 15 MPa. It has been found that the energy of dissociation of gadoliniumvacancy complexes is Eeff D= 0.26 ± 0.06 eV, and the energy of dissolution of helium in anion vacancies in the impurity disorder region is EP= -0.31 ± 0.09 eV. The proposed mechanism of dissolution has been confirmed by the investigation of the electrical conductivity of the cerium gadolinium ceramics, as well as by the high-speed molecular dynamics simulation of the dissociation of gadolinium-vacancy complexes. It has been assumed that a decrease in the effective dissolution energy in comparison with the results of the previously performed low-temperature investigations is caused by the mutual repulsion of vacancies formed upon the dissociation of gadolinium-vacancy complexes in highly concentrated solutions of gadolinium in CeO2with increasing temperature. © 2013 Pleiades Publishing, Ltd

Fluoride technology of obtaining REM magnetic alloys and master alloys

Rare earth permanent magnets (REPM) based on neodymium-Fe-boron system are the most promising, since they have the highest magnetic and satisfactory mechanical characteristics. The paper covers physical-chemical principles and shows the results of experimental studies of the process of obtaining REM alloys and master alloys using fundamentally new fluoride technology based on ladle calciothermal REM fluorides and Fe reduction

Grain quality indicators and size-dependent fractional composition in winter rye cultivars under the conditions of the Lower Volga region

Background. Grain quality indicators of winter rye cultivars were analyzed in connection with the size-dependent fractional composition of their grain in the Lower Volga environments.Materials and methods. The research material included 22 cultivars developed at various Russian scientific institutions, 3 Belarusian ones, and 3 cultivars bred at the Federal Center of Agriculture Research of the South-East Region. Comparative trials were conducted in 2021–2022 on 13.2 m2 plots in two field replications. The following grain quality indicators were studied: grain test weight, 1000 grain weight, size-dependent fractional composition, Hagberg falling number, amylogram peak height, starch gelatinization temperature, protein content, and rheological properties of the meal/water slurry.Results. Protein content was recorded at a level of 9.98–10.85%, while the starch gelatinization temperature was high due to the June air temperatures higher than the norm. Significant differences among the cultivars were found in the fractional composition of grain: 12 forms were identified with medium viscosity of the meal/water slurry and the fine-grain fraction content up to 30% of the total weight.Conclusions. There is a positive significant correlation between the five studied indicators characterizing the rheological properties of the meal/water slurry made from the grain of winter rye cultivars and the grain fraction composition (0.82*–0.91*)

Fluoride technology of obtaining REM magnetic alloys and master alloys

Rare earth permanent magnets (REPM) based on neodymium-Fe-boron system are the most promising, since they have the highest magnetic and satisfactory mechanical characteristics. The paper covers physical-chemical principles and shows the results of experimental studies of the process of obtaining REM alloys and master alloys using fundamentally new fluoride technology based on ladle calciothermal REM fluorides and Fe reduction

Perspectives of Siberian chemical plant in increasing volumes of uranium concentrates recycling

The purification technology of uranium concentrate of natural isotopic composition developed at Siberian chemical enterprise is basically universal, allows recycling uranium concentrates with different content of impurities and obtaining uranium nitrate solutions corresponding by quality to the international standards requirements to uranium hexafluoride preparation for isotopes ASTM C 787-03 separation and to ceramic fuel ASTM C 788-02 preparation. Uranium reserves in Russia and abroad were appraise