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We report the spark discharge synthesis of aerosol germanium nanoparticles followed by sintering in a tube furnace at different temperatures varying from 25 to 800 &deg, C. The size, structure, chemical composition and optical properties were studied. We have demonstrated a melting mechanism of nanoparticles agglomerates, the growth of the mean primary particle size from 7 to 51 nm and the reduction of the size of agglomerates with a temperature increase. According to transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) data, primary nanoparticles sintered at temperatures from 25 to 475 &deg, C basically have a structure of Ge crystals embedded in a GeOx amorphous matrix, as well as visible photoluminescence (PL) with the maximum at 550 nm. Pure germanium nanoparticles are prepared at temperatures above 625 &deg, C and distinguished by their absence of visible PL. The shape of the experimental UV-vis-NIR extinction spectra significantly depends on the size distribution of the germanium crystals. This fact was confirmed by simulations according to Mie theory for obtained ensembles of germanium nanoparticles.

A series of previously undescribed N-aryl-N′-pyridin-2-ylureas were prepared via the reaction of 2-aminopyridines with benzoyl azides and tested in vitro as activators of glucokinase. Statistically significant reductions of glucose levels as compared with controls were demonstrated for several compounds.

The process of scattering of radiation by indium‒tin oxide (ITO) nanoparticles is theoretically studied at various degrees of doping and for different radii of nanoparticles. Qualitative conclusions are made about the character of the dependence of the scattering cross section on the frequency with variation of the particle size and the percentage content of tin. The prospects of using ITO nanoparticles as an active substance in optical sensors are estimated.

The paper presents the general scheme of operation and the physico-mathematical model of an optical plasmon sensor based on indium-tin oxide (ITO) nanoparticles. The principle of operation of the "ITONPsensor" program intended for simulation of a response of the optical plasmon sensor to a change in parameters of a medium being measured is also described. The program was developed on the basis of the physico-mathematical model of absorption of radiation by semiconductor ITO nanoparticles.

In this work, the in-situ upgrading of heavy oil from Tatarstan oilfield using steam and copper stearate as a catalyst at 250 °C and 35 bar for 24 hours was studied in stainless-steel reactor. Changes in the density/API gravity, viscosity, chemical composition (SARA-analysis), elemental composition and structure (FTIR-spectroscopy) of heavy oil before and after conversion were determined. Generally, we can summarize, that the content of resins and asphaltenes as well as the average molecular weight of heavy oil were reduced after conversion process. Whereas, amount of saturated and aromatic hydrocarbons was increased due to the destruction of its high molecular weight components. Also, irreversible decrease of viscosity was fixed.

The thickness of aluminum oxide thin films fabricated by technology of atomic layer deposition with different number of cycles measured by small angle X-ray scattering. The dependence of the film thickness in the range of 20–120 nm from the number of ALD process cycles is linear.

The interaction of synthetic analogs of active centers of iron-sulfur proteins with phosphates of different structures was studied. It was shown that the process involves ligand exchange and obeys the first-order reaction kinetic equation. The most rapid exchange occurred with the most acidic compound diphenyl phosphate.

The Mossbauer parameters (the isomer shift δ, the quadrupole splitting ΔE, and the probability of recoilless absorption f') have been analysed for a large number (more than 200) of complexes of mono- and bi-dentate organophosphorus complexes with tetra-alkyltin and alkyltin halides. It is shown that the Mossbauer method can be used to determine the localisation centres of the donor–acceptor bond in complexes of organophosphorus compounds with tin tetrahalides and to determine the geometrical structures of the complexes. It has been observed that the quantities δ, ΔE, and f' for the compounds [R'R''R'''P(Y)]2(1)SnRnX4–n are definitely influenced by the nature of the substituents in the ligand and in the acceptor. This influence can be described with the aid of the reaction constants of the substituents σph and σ*. The bibliography includes 110 references.