Textural states of a hot-worked MA2-1 magnesium alloy

Quantitative texture analysis is used to study texture formation in an MA2-1 magnesium alloy subjected to axisymmetric upsetting at temperatures of 250–450°C and strain rates of 10^?4–10^{0 ?1}. The deformed structure is examined by optical microscopy, and the results obtained are used to plot the structural-state diagram of the alloy after 50% upsetting. The experimental textures are compared with the textures calculated in terms of a thermoactivation model.     

Characteristics of tunneling and impact ionization in ZnS:Mn-based thin-film electroluminescent structures

A method for measuring the characteristics of tunneling and impact ionization in thin-film electroluminescent emitters is suggested. This method makes it possible to find time dependences of the space-charge layer thickness near the anode and the length of the impact ionization region, to determine more exactly the time dependence of the field in the potential barrier at the cathode interface, the maximum depth of the surface states from which electron tunneling occurs, the minimum thickness of the barrier, and the electron tunneling probability, as well as the impact ionization rate for the deep centers related to structural defects of the phosphor layer.     

Electric-discharge cleaning of surfaces of manufacturing equipment from foreign nonmetallic deposits

Processing characteristics of the electric-discharge cleaning of surfaces of manufacturing equipment from foreign nonmetallic deposits of different durability are researched. To expand the capabilities of the cleaning of manufacturing equipment, a complex cleaning method is proposed.     

Catalytic properties of composite amorphous carbon-platinum layers in fuel cells

Catalytic properties of composite amorphous carbon-platinum layers produced by magnetron cosputtering have been studied. The layers were characterized by electron microscopy, IR spectroscopy, ellipsometry, gravimetry, and spectrophotometric chemical analysis. The catalytic activity of the layers was studied in an air-hydrogen fuel cell by measuring its load and power characteristics.     

A controllable chaotic system based on inductively coupled bistable oscillators

A mathematical model of a new controllable autooscilatory chaotic system based on inductively coupled Chua’s oscillators is described. Numerical simulations show that, using a chaotizing feedback algorithm, chaotic oscillations in this system can be excited in regimes where only regular oscillations are generated otherwise.     

Methane conversion in a plasma created by a periodic-pulsed electron beam and non-self-sustained discharge

The process of methane conversion in a mixture modeling the natural gas under the action of a periodic nanosecond pulsed electron beam and an electron-beam-induced non-self-sustained discharge has been numerically simulated and studied in experiment. The possibility of methane conversion under the action of electric pulses without significant heating of the processed gas mixture is demonstrated for the first time. The main conversion products in experiment were hydrogen, ethylene, and acetylene.     

Unsteady heat transfer in a system of three coaxial finite cylinders

An integral transformation with the aid of which a solution of the problem of unsteady-state heat transfer in a system of three coaxial finite cylinders with different boundary conditions on their surfaces depending on space and time is presented. Each of the cylinders evolves heat of a certain intensity, depending on time and coordinates. A numerical solution of one variant of the boundary conditions is given and illustrated by figures. The method of transforming the solution of the problem with other boundary conditions is shown. __________ Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 80, No. 1, pp. 140–148, January–February, 2007.     

Problem on estimation of the content of <Superscript>131</Superscript>I in milk in the “iodine” period of the Chernobyl accident

Measurements of the beta-activity of milk, serving as the main source of information on the radioactive contamination of the environment by the iodine isotope ¹³¹I, carried out on a DP-100 radiometer in the early post-Chernobyl period (1986) in Belarus, have been mathematically simulated. The results obtained allow the conclusion that the indicated measurements should be analyzed again with consideration for all of the nuclides present in milk. __________ Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 80, No. 6, pp. 102–108, November–December, 2007.     

Internal nonlinear four-mode interactions of capillary oscillations of a charged drop

Analytical expressions for the shape of a charged drop of an incompressible liquid nonlinearly oscillating upon multimode initial deformation have been obtained for the first time to within the third order of smallness. The second-order corrections to oscillation frequencies are calculated depending on the spectrum of modes determining the initial deformation. The third-order calculations show that the fundamental mode amplitude may increase due to the energy exchange with higher modes in a large number of possible four-mode resonance interactions.