Effect of Burnup and Holding Time of Irradiated Nuclear Fuel on the Mass Ratio of Am, Cm, Np, and Fissioning Plutonium

Computed estimates of the mass ratio of Am, Cm, Np, and plutonium for different burnup of VVÉR and RBMK fuel and the post-reactor holding time are presented. The holding time for which this ratio reaches the admissable value 0.32 is determined.     

Coercive-force and eddy-current testing of the abrasive wear resistance of quenched and tempered hypereutectoid carbon steels: II. Steels subjected to different quenching regimes,subzero treatment,and tempering after high-temperature quenching

The effects of the carbon concentration in martensite from 0.70 to 1.35 wt %, the presence of up to 70 vol % residual austenite, the degree of coagulation, and the volume fraction of tempering carbides on the specific features of the application of eddy-current and magnetic methods for testing abrasive wear resistance are studied. The case of high-carbon (0.83–1.53 wt % C) steels quenched from 790–1200° C, treated with cold at ?196°C, and tempered in the temperature range 75–700°C is considered.     

Influence of Calcium Phosphates on the Morphology and Properties of Polylactide Composites

Materials Science - We developed polylactide composite materials with calcium-containing fillers; in particular, calcium orthophosphate and calcium hydroorthophosphate. It is shown that the degree...     

Modelling of the thermodynamic properties of the water–ammonia mixture by three different approaches

This paper deals with the modelling of the thermodynamic properties of the water–ammonia refrigerant mixture. Three different approaches are formulated and compared. The first is an empirical approach based on a free enthalpy model of the mixture considered as the resultant of the properties of its pure components and of an excess term corresponding to the deviation to the ideal solution concept. Secondly, a semi-empirical approach based on the PATEL and TEJA cubic equation of state is considered. Finally, a theoretical approach formulated as PC-SAFT (perturbed chain statistical associating fluid theory) equation of state is treated. A comparison of these three methods proves the superiority of PC-SAFT in predicting and extrapolating the thermodynamic properties of the water–ammonia system up to very high temperatures and pressures.     

Computational method for investigation of solid fuel combustion in combustion chambers of a heat power plant

Solid fuel combustion in an actual combustion chamber using coal with an ash content of more than 40% for minimization of the deleterious effects (environmental pollution) of heat power plants on environment. The FLOREAN application package was used for simulation and determination of various parameters of combustion.     

Point Dynamic Loads on a Sandwich Structure

Russian Engineering Research - The action of dynamic point loads on a three-layer structure with fiberglass filler is studied experimentally. The experimental data are compared with theoretical...     

Ensuring Lateral Clearance in Gears by Displacing the Initial Tool Contour

Russian Engineering Research - Multicriterial optimization of gear engagement by means of Kompas-3D software permits calculation of the tool displacement required to ensure lateral clearance in...     

Chromium combustion in a nitrogen coflow

The combustion of chromium powder in a coflow of nitrogen-containing gas in a range of specific flow rate of up to 20 cm³/(s · cm²) is studied. The use of forced filtration intensifies the combustion wave propagation in the Cr–N₂ system. In this case, the combustion rate increases simultaneously with the decreasing degree of nitridation. The superadiabatic heating modes in the case of purging with pure nitrogen and a hydrogen-argon mixture are revealed. It is shown that the use of the gaseous mixture promotes the formation of the inverse combustion wave. The hardening mode implemented during forced filtration allows fixing the high-temperature single-phase nonstoichiometric nitride Cr₂N.