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Using the method of computer thermodynamic modeling, the stability of higher fullerene C90 heated in a nitrogen atmosphere at a pressure of 0.1 MPa is studied. The simulation is performed using the TERRA software package in the temperature range from 273 K to 3373 K. The equilibrium composition of compounds in the C90–N2 system is obtained and the physico-chemical processes causing the formation of these compounds are described. The equilibrium constants of the processes forming the equilibrium composition of compounds are calculated for different temperature ranges using the least squares method. [ABSTRACT FROM AUTHOR]

The method of thermodynamic modeling—complete thermodynamic analysis of the system with application of the program complex TERRA—is used for studies on the behavior of fullerene C90 during heating in nitrogen atmosphere. Investigations were performed under conditions of nitrogen excess and deficiency. The experimental temperature range is from 273 to 3373 K, at pressure of 0.1 MPa. [ABSTRACT FROM AUTHOR]

More than 100 power reactors, reactors for plutonium production, and research reactors are presently available in the world. In these reactors, graphite is used as a reflector, moderator, and cladding of fuel elements. Flameless combustion is a promising method for reducing the amount of solid radioactive waste. The method is based on the oxidation of solid radioactive waste in oxide–carbonate melts and makes it possible to reduce the radioactive graphite volume considerably. Thermodynamic simulation and analysis of the oxidation of radioactive graphite in molten Na2CO3–K2CO3–Sb2O3 in a carbon dioxide atmosphere are performed using the TERRA software package. The thermodynamic simulation is conducted at a pressure of 1 atm and initial and final temperatures of 273 and 3273 K, respectively. The step of temperature changing is 100 K. Based on these data, the distributions of elements between condensed and gas phases are examined. The simulation results show that carbon disappears at a temperature of 873 K. Heating of the system up to 1073 K leads to the evaporation of condensed antimony compounds. Heating of the system up to 1673 K leads to the evaporation of condensed potassium, sodium, chlorine, uranium, and cesium compounds. Heating of the system up to 2273 K leads to the evaporation of condensed nickel compounds. Heating of the system up to 2573 K leads to the evaporation of condensed calcium, plutonium, beryllium, strontium, americium, and europium compounds. Only a vapor–gas phase is observed at temperatures above 2573 K. [ABSTRACT FROM AUTHOR]

Abstract—Graphite is used as a neutron moderator and reflector. Moreover, graphite can be used as sealants and bearings in reactors. The graphite mass in a reactor is 1-2 ths t. A large amount of radioactive graphite wastes forms when graphite reactors are taken out of service. The existing methods of processing radioactive graphite are based on its isolation from the environment. These methods cannot substantially decrease the volume of radioactive graphite wastes. As a result, the processing of irradiated reactor graphite by oxidation in molten salts can be considered as an alternative reclamation method, which can decrease the volume of radioactive graphite wastes. The oxidation of radioactive graphite in the Na2CO3-K2CO3-Sb2O3 melt in an argon atmosphere is thermodynamically simulated using the TERRA software package. The data obtained are used to analyze the distribution of elements over condensed and gas phases. Heating of the system to 1073 K is found to cause the evaporation of the condensed compounds of antimony and cesium. Upon heating to 1273 K, the condensed compounds of potassium, sodium, and chlorine evaporate. Heating to 1373 K leads to the evaporation of the condensed compounds of nickel. Heating to 1673 K brings about the evaporation of the condensed compounds of uranium, calcium, and strontium. Heating to 1773 K causes the evaporation of the condensed compounds of plutonium, beryllium, americium, and europium. At temperatures above 1773 K, only a vapor-gas phase exists in the system. [ABSTRACT FROM AUTHOR]

Total endoprosthetic hip replacement was performed in 39 patients with femoral head protrusion. The necessity of acetabulum defect infilling is proved. For the purpose of it the ground allobone transplant was impacted using the originally constructed impactor. The maximal volume of bone transplant was 170sm3. Reconstruction of the rotation center was achieved in 82% cases. 18% failed to reconstruct the anatomic rotation center, though without the significant limb contraction. The functional result was evaluated according to Harrison's scale after 6-48 months after the operation.87,2% of patients demonstrated good and 12,8% - satisfactory results in a 6 months period. There were no negative results in the group.