The effect of the alloying elements of a CoNiCrAlY system on the corrosion resistance of alloys for protective coatings of gas turbine blades

Results from testing for resistance to sulfide-oxide corrosion of model alloys used to make possible CoNiCrAlY system-based protective coatings are presented. The effect exerted by Ni, Cr, Al, and Y on the corrosion resistance of these coatings at different temperatures is determined, and equations for calculating the chromium equivalents of these coatings are obtained.     

The dislocation anharmonicity in silicon

The effect of the dislocation anharmonicity on the Young modulus in bending silicon single crystals was studied. It is shown that changes in the Young modulus are caused by the contribution of dislocations to the fourth-order elasticity moduli. It is revealed experimentally that the bending deformation in both donor and acceptor silicon crystals favors the appearance mainly of the edge dislocations with the axes forming an angle θ∼90° with the Burgers vector.     

Boiling of Thermally Unstable Liquids in Processes with Rapid Heating

A spontaneous boiling of liquids, the heating of which is accompanied by reactions of thermal decomposition, is treated. Results are given of measurements of the boiling temperature of liquids on the surface of a filament heater whose temperature rises at a rate of 10⁵–10⁸ K/s. Based on the experimental data, a model is suggested for the calculation of the boiling temperature of thermally unstable liquids under conditions of rapid heating.     

Handling toxic wastes during salvaging and rehabilitation of nuclear objects in north-west Russia

Systematized information on toxic wastes produced during salvaging and rehabilitation of decommissioned nuclear and radiation-hazardous objects in the nuclear-powered naval fleet in north-west Russia is presented. The dynamics of their accumulation up to 2025 is estimated. Substantiation is given for the need to re-examine the existing system of handling wastes and searching for new solutions for decreasing the ecological risk by systematically reprocessing or eliminating them together with gaining an ecological advantage. Such an approach requires upgrading and developing infrastructure at the salvaging enterprises and objects undergoing rehabilitation. Several strategies are examined. The advantages and disadvantages of each strategy are evaluated according to safety and cost factors and the most acceptable strategy is chosen. A functional model is created. A list of projects and technical means is presented, and the time periods and costs required for implementation are estimated. The priority directions of work are identified. Translated from Atomnaya énergiya, Vol. 105, No. 6, pp. 345–352, December, 2008.     

Mathematical modelling of perorally induced immunological tolerance

A mathematical model of the mechanism of development of orally induced immunologic tolerance has been suggested. The model presents a system of differential non-linear equations, and it is realized as a program in FORTRAN. The model describes primary and secondary immune responses, reflects the main features of the immune system response to antigen intake with food. The immune system model response to varying doses and frequency of the antigen intake with food has been studied. It has been established that repeated administration of small doses of the food antigen leads to a deeper tolerance due to lower stimulation of the immune system. The existence of optimal tolerogenic doses of the food antigen has been proved. Qualitative changes in the immune system response to the food antigen have been recorded in case of increased permeability of the intestinal wall.     

Stress and plastic deformation of MEA in running fuel cell

Numerical modelling of mechanical stresses in running fuel cell is provided. The evolution of stresses and plastic deformations in the membrane has been obtained during the turn-on phase. The operating conditions have been taken into account by imposing the heating sources and the humidity field. The results have been presented on two scales: the global scale reflects the stress evolution in the entire fuel cell and the local one corresponds to the tooth/channel structure. It has been shown that the stresses are strongly heterogeneous on the both scales and time dependent. From the mechanical point of view, the most sensible zone is under the GDL/seal joint interface. In the running fuel cell the heterogeneity decreases while it rises in the fuel cell just after the assembly. The stresses reach the maximum values during the humidification step, the magnitude of these stresses is sufficient for initiation of the plastic deformations in the Nafion membrane.