This paper presents a study of the gas sensitivity of a nanostructured zinc oxide coating to isopropyl alcohol vapor during heating, ultraviolet irradiation, as well as simultaneous heating and irradiation. Simultaneous heating to 150oC and ultraviolet irradiation ensures an increase in the sensor layer response. A 10-fold decrease in the power consumption of an ultraviolet light-emitting diode results in a 1.2-fold decrease in the response of the sensor coating. Reducing the operating temperature of a gas sensor with low power consumption and achieving the required sensitivity can provide adsorption sensors integration into portable devices for monitoring ambient air quality. Keywords: zinc oxide, nanorods, gas sensor, UV irradiation, combined activation.

A model of an autonomous receiving station of free space optical communication system based on a multi-section energy heterostructure (HJT) Si photoconverter and an information photodetector based on AlGaAs/GaAs p-i-n photodiodes has been developed. The energy part, when excited by laser radiation with a power of ~ 264 W at a wavelength of 0.974 μm in the photovoltaic mode, provided ≥ 60 W of electric power. The photodetector of the information channel, when excited by pulsed radiation at a wavelength of 0.78 μm, provides response time in the photovoltaic mode in the sub-nanosecond range. Keywords: free space opical communication, receiving station, HJT Si photoconverter, AlGaAs/GaAs p-i-n photodetector, laser radiation, pulsed radiation

Using Messbauer spectroscopy on 119Sn impurity atoms, it was demonstrated that in amorphous (GeTe)x(Sb2Te3) films (where x=0.5, 1, 2, 3) tin atoms replace atoms of tetravalent germanium, which forms a tetrahedral system of chemical bonds with atoms in its local environment. In crystalline films, tin replaces divalent six-coordinated germanium in positions 4b of the NaCl-type crystal lattice. Keywords: amorphous films, phase memory, Messbauer spectroscopy.

By the method of Messbauer spectroscopy on the isotope 119Sn, it was shown that tetravalent germanium atoms in amorphous films (GeTe)x(Sb2Te3) (where x=0.5, 1, 2, 3) form a tetrahedral system of chemical bonds, and in their local environment there are mainly tellurium atoms. In crystalline films (GeTe)x(Sb2Te3) is divalent hexoordinated germanium at positions 4 b of the NaCl type crystal lattice. By the meth-od of Messbauer spectroscopy on 121Sb and 125Te atoms, it was shown that the amorphization of (GeTe)x(Sb2Te3) films does not change the lo-cal environment of antimony and tellurium atoms Keywords: amorphous films, phase memory, Messbauer spectroscopy.