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We study the influence of temperature of a working medium and loading frequency on the contact fatigue of 20KhN3A and ShKh15 steels in oil and in a 3% NaCl aqueous solution. It is shown that, as the loading frequency increases, the contact fatigue of steels increases in a 3% NaCl aqueous solution but does not change in oil. At the same time, as temperature increases, the contact fatigue decreases in a 3% NaCl aqueous solution but remains almost constant in oil. It is shown that the outlined behaviors of the analyzed steels is explained by the action of the components of working media and their concentrations in the surface layers in the course of the tests. [ABSTRACT FROM AUTHOR]

The adsorption of oligo(sebacoyl peroxide) on Aerosil and MgO and benzoyl peroxide on Fe 2O 3, Cr 2O 3, and V 2O 5 has been studied. It has been established that peroxide adsorption on the considered adsorbents is described by the Langmuir equation. Benzoyl-peroxide adsorption increases in the series Fe 2O 3 < Cr 2O 3 < V 2O 5. The process of thermal decomposition of peroxides in the presence of the listed adsorbents has been studied. The overall reaction of peroxide decomposition comprises two components, i.e., the decomposition processes occurring in a solution and on an adsorbent surface. Kinetic and activation parameters of the thermal-decomposition reactions in the solutions and on the surfaces have been determined. [ABSTRACT FROM AUTHOR]

It is established that the use of a previously proposed variant of the finite-element method for solving nonlinear nonstationary heat-conduction problems is efficient (in the sense of computer time expenditures) when the half-width of the band β of the resulting matrix in the system of linear algebraic equations does not exceed a certain value of βcr. As a result of a numerical experiment for an axially symmetric case we obtain βcr ≈ 47, which demonstrates the effectiveness of this variant of the finite-element method for solving a wide range of practical problems of heat-conduction theory. [ABSTRACT FROM AUTHOR]