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The paper considers problems to define the primary source of raw material for metallurgical production in the Bronze Age in the IV-II centuries BC on the steppe Sic-Urals area. The data of field, experimental, and geochemical analytical researches for 2016-2020 are used. The summary indicating the relation between the initial ore protolith and sulfide and silicious-carbonate oxidized ores dated by the end of the Permian period is formulated. Radiocarbon dates of bearing monuments of mining archaeology are given.

To measure high-frequency and low-frequency impedance of betavoltaic power sources (it can be represented as two-terminal device), measurement stand was created. To measure high-frequency part need to inject external test signal through the current transformer with waveform generator and need to use external high-frequency current sensor, because of SMU PXIe-4139 current channel limitations.

The model of electron-hole pairs generation rate distribution in semiconductor is needed to optimize the parameters of microporous silicon betaelectric converter, which uses 63Ni isotope radiation. By using Monte-Carlo methods of GEANT4 software with ultra-low energy electron physics models this distribution in silicon was calculated and approximated with exponential function. Optimal pore configuration was estimated.

Some results on planar diode structure creation by the method of a plasma-immersion ion implantation is presented in this paper. Obtained leakage current ~ 1 uA/cm2 at reverse voltage -1 V.

The cryogenic plasma chemical silicon etching process is developed, able to form the structured silicon layer with system of deep holes with high aspect ratio.

The transfer matrix mathod is used in a theoretical analysis of the transformation of a Gaussian beam passing through various optical elements of a laser anemometer such as lenses, inclined plane-parallel plates, and media with different refractive indices. The transfer matrices are found for an inclined plate and for the investigated medium bounded by two plates. Analytic expressions are derived for the beam parameters in the medium under study, including the position, dimensions, and radii of curvature of the beams in the meridional and sagittal planes. The misalignment of the laser anemometer optical system is calculated by scanning the element under study along the bisectrix of the intersection of two beams allowing for astigmatism. The main theoretical conclusions are compared with the experimental results.

An analysis was made of the power requirements of an acoustooptic deflector and it was found that for a given minimum diffraction efficiency there is an optimal value of the maximum efficiency at which the power consumed by a defletor is lowest (provided acoustic scanning is not used in the deflector).