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The results of experimental investigations of the heat transfer by lead coolant in the ring-shaped gaps of a circulation loop during monitored and controlled mass transfer and mass exchange of oxygen and impurity are presented. The investigations were performed in a loop with circulation of lead coolant at temperature of 450–550°C, average velocity 0.1–1.5 m/sec, Peclet number 500–6000, and heat flux 50–160 kW/m2. The oxygen content in the loop was varied from the value for thermodynamic activity 10−5–100 to saturation and above with formation of lead oxide deposits on the heat transfer surface. The processes in a non-isothermal liquid metal loop with heating (core) and cooling (steam generator) experimental sections simulate the dependence of the heat transfer characteristics in the loop on the impurity mass transfer.

The spectra and decay time of pulsed cathodoluminescence (PCL) of a scintillating crystals excited by the electron beam is compared to the spectra and decay time of the luminescence of the same crystals initiated by γ-rays (GL). It is shown that spectra and decay time of PCL and GL are identical within the experimental errors. The explanation of these results is based on taking into account the physical processes within the crystal media under the irradiation by high-energy particles. The results of this study confirm that the PCL method may be used for the rapid analysis of the luminescent properties of scintillators.

The ring mode of the Trichel pulse negative corona discharge was studied in atmospheric air. The localization of the discharge flame track in the stable self-organized regular pattern of 3, 4, 5 and 6 – pointed star was found at the cathode surface. This phenomenon was observed at mean currents in the range 100-115 μA at the conditions of the experiment, when the modes with one or two rings are not stable. The conclusion was made that the ring mode of the discharge, which is caused by the symmetrical distribution of the volumetric charges in the conditions of the symmetrical electric field, may be unstable. This instability results in the spatial self-organization of these parameters and causes the organization of the discharge flame track at the cathode surface in the regular patterns.