The paper studies ferrite pastes based on lithium-containing ferrite (Li0.4Fe2.4Zn0.2O4). A selection of the binder composition is described herein. Pastes based on the binding terpineol with polyethylene glycol demonstrate the best porosity and application quality. The frequency response of the microstrip transmission line with a ferrite sublayer is studied. As a result, the determined parameters of the ferrite layer are determined to be the dielectric permittivity (ε = 16), loss-angle tangent (tanδ = 0.3) and magnetic permeability (μ = 40).

This study investigates the excited states within oligomeric fluorene compounds containing up to 20 monomer units in various conformations. Furthermore, it explores the impact of donor and acceptor substituents in the side chain. Time-dependent density functional theory (TD-DFT) simulations were conducted at the B3LYP/def2-svp level of theory. Results indicate localized excitation, primarily spanning 8-13 monomer units, irrespective of donor and acceptor substituents. These findings offer insights into charge carrier mobility, electroluminescent properties of polyfluorenes, and facilitate the design of novel materials within this class.

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A theoretical study of extrusion of a paste consisting of a silver powder in a terpineol binder is performed, aimed at getting an insight into the system’s behavior and determining the optimal conditions of the dosing mechanism operation. The paste is treated as a non-Newtonian fluid, and its characteristic properties are taken from the experiment. The spatial distributions of its viscosity, motion velocity, and excessive pressure are plotted for the characteristic cross-section of the paste during its extrusion. The viscosity distribution map is obtained as a function of the paste velocity and the distance from the nozzle during extrusion. It is shown that a pseudo-plastic behavior of the paste plays a decisive role in selecting the nozzle-to-substrate distance and determines the quality of the resulting film. The curves of dependence presented in the study would serve optimizing the extrusion process using a piston dosing mechanism.

The feasibility of application of a ferromagnetic conductive cylinder nozzle to focus the fluid flow extruded by a piston dispenser is assessed in the present work. Based on the limiting cases of stationary and laminar fluid flows, it is shown that an electric field can be created between the fluid and the cylindrical nozzle due to the anomalous Hall effect in the cylindrical nozzle with a current flowing along the cylinder. This field is created by the electric current caused by the mechanical movement of the fluid. This electric current of the fluid creates around itself the cylindrical magnetic field that penetrates into the ferromagnetic nozzle. On the example of carbonyl iron, it is shown with allowance for the corresponding approximations that an increase in the current flowing through the ferromagnetic nozzle should lead to a decrease of the fluid flow radius.

— The optical properties of Al–Si–N nanocomposite coatings deposited by reactive magnetron sputtering on substrates of stainless steel 12H18N10T and zirconium alloy E110 are studied. The absorption and luminescence characteristics are determined by growth defects and also depend on the type of substrate and its treatment with a powerful ion beam. Absorption and luminescence centers are identified with intrinsic defects in c -Al and a -SiN x and their simplest complexes. The effect of hydrogen absorption and 420-keV proton irradiation on the optical properties of the coatings is established. The dose dependences of the optical characteristics indicate the radiation resistance of the coatings. The radiation resistance of the coatings on zirconium alloy is slightly higher due to the stabilizing effect of silicon-containing defects.

The effect of short-pulsed irradiation with 220 keV carbon ions for fluences of 2.2 x 10(13) - 2.1 x 10(15) cm(-2 )on the optical and electrical properties of titanium nitride films deposited by reactive magnetron sputtering on silicon and steel substrates has been studied. Relationships are obtained between the irradiation conditions and the parameters of interband absorption. A relationship has been established between the concentration of defects before and after irradiation, the degree of overlap of their levels and changes in the optical and electrical properties of the films. Reasons of high radiation resistance of the films are discussed. The optical and electrical properties of the films change during irradiation in two stages. The first stage is related to the annihilation of defects, the second stage is associated with their accumulation. Irradiation of films significantly slows down the rate of oxidation of their surface layers and stabilizes the electrical properties.

The effect of short-pulse irradiation with 200-keV carbon ions on the optical and electrical properties of aluminum-nitride films and Al–Si–N coatings with variable atomic composition deposited by reactive magnetron sputtering on a silicon substrate is investigated. Absorption and luminescence centers are associated with growth and radiation-induced defects in nitrides and their simplest complexes. A change in the properties during irradiation occurs due to the accumulation of radiation defects and their association into complexes. Ion irradiation is accompanied by intense radiation and the thermal annealing of unstable defects. The dose dependences of the coating characteristics indicate their high radiation resistance, which are slightly inferior to coatings on steel substrates. The radiation resistance of the coatings is due to the limiting effect of growth defects on defect formation, the wide band gap of nitrides and the interaction of defects.

This paper presents the results of a study of the effect of energy conditions (additional heating of the walls of the reaction chamber and subsequent action of an electron beam on the synthesized powder) of pulsed plasma-chemical synthesis on the morphology, average geometric size, phase and chemical composition of copper-containing silica-based nanocomposites. The nanocomposites were synthesized using a TEA-500 pulsed electron accelerator. It was the first time that copper-containing silica-based nanocomposites had been prepared using the pulsed plasma-chemical synthesis. The values of the band gap for the as-prepared nanocomposites were calculated. The nanocomposites were characterized by means of transmission electron microscopy and X-ray diffraction. The analysis revealed the changes in the morphology and phase composition of the nanocomposites upon energy conditions.

A series of novel D–A–A push-pull systems based on a 2-cyanopyrazine acceptor core bearing various electron-donating fragments are synthesized and investigated. The effect of the cyano group on the spectral-luminescent properties of molecules in solvents of different polarities and films obtained by thermal vacuum deposition has been investigated. Fast and delayed luminescence was studied at room temperature and 77K. The energy gap between the S1 and T1 states is estimated. The reasons for the weak thermally activated delayed fluorescence are discussed. It has been found that increasing the efficiency of light-emitting organic diodes up to 20 times took place when a cyano group introduces into fluorophores.

Using the method of the density functional theory (DFT/B3LYP/6-31G(d,p)), the vibrational absorption and emission spectra of bifluorene and terfluorene molecules are calculated. A good agreement is obtained between the model and experimental spectra. The vibrational promoting modes forming a vibronic progression in the emission bands are determined.

In this work, the TiO2@TixCyOz nanocomposite was obtained by adding a buffer gas to the initial mixture of reagents by the pulsed plasma-chemical method. Argon was used as a buffer gas. Pulsed plasma-chemical synthesis was realized using a TEA-500 electron accelerator. The physicochemical properties of the obtained TiO2@TixCyOz nanocomposites (morphology, average particle size, elemental, and phase composition) were studied. It was shown that by changing the buffer gas concentration, it was possible to control the phase composition, particle size, and shell thickness of TiO2@TixCyOz nanocomposites. The values of the band gap were calculated for the synthesized TiO2@TixCyOz nanocomposites. The photocatalytic and adsorption properties of TiO2@TixCyOz nanocomposites were studied.

This work presents the results of pulsed plasma-chemical modification of silicon dioxide nanopowder with zinc oxide nanoparticles (ZnO@SiO2). The obtained ZnO@SiO2 powders were characterized by transmission electron microscopy (TEM) and X-ray phase analysis. The size of the synthesized particles was in the range of 20–100[Formula: see text]nm. The photocatalytic characteristics of ZnO@SiO2 were studied. When exposed to ultraviolet radiation, the methylene blue (MB) decomposes efficiently. Two samples characterized by the content of silicon tetrachloride in the initial mixture were synthesized. The band gap estimated from the absorption spectra calculated from the diffuse reflectance spectra for these samples was 2.4[Formula: see text]eV and 2.95[Formula: see text]eV for indirect transitions and 3.03[Formula: see text]eV and 3.24[Formula: see text]eV for direct allowed transitions.

In this paper, we study the optical properties of aluminum- and silicon-nitride films and Al–Si–N coatings with variable atomic composition deposited by reactive magnetron sputtering on glass, silicon, and steel substrates. The absorption and luminescence characteristics are determined by the composition of the coatings and microstructure and depend on the physical properties of the substrate. The absorption and luminescence centers are associated with intrinsic defects in the nitrides and their simplest complexes. The relationships between the accumulation of growth defects, their interaction, the type of distribution of localized states, the band gap, and the stability of the optical properties are established. At an increase in the silicon content in the coatings, the degree of static induced disorder increases, and the contribution of the continuous distribution of the defect levels and interband absorption increases. Silicon-containing defects stabilize the optical properties of the coatings.

A series of novel D-A and D-pi-A push-pull systems based on a pyrazine and quinoxaline acceptor, bearing various electron-donating triphenylamine and carbazole moieties, are compared. A significant difference in electrochemical and photophysical properties was found depending on molecular structure. The compounds have strong solvatochmmic properties. Quinoxaline-containing systems exhibit delayed fluorescence (DF) in thermal vacuum deposition films. Despite the low quantum yield of fluorescence in the solid state (less than 10%), organic light-emitting diodes with sufficiently high efficiency (4.2 cd/A) have been fabricated on the basis of this push-pull systems. The best results were obtained for compounds exhibiting DF. The possible channel for increasing the efficiency of OLED can be associated with the "hot excitons" mechanism.

The article reports on radiation defect formation parameters and radiation resistance of multilayer coatings from thin layers of aluminum and silicon nitrides deposited on sodium-calcium-silicate glass and monocrystalline silicon substrates by reactive magnetron sputtering. The samples were irradiated with helium ions of 28 MeV on a cyclotron and carbon ions 200 keV on an accelerator in the mode of short-pulse implantation. The characteristics of local absorption and luminescence centers before and after irradiation and their probable nature were determined. The optical centers had been identified as point intrinsic defects of a growth and radiation nature. The accumulation of radiation defects in layers of amorphous silicon nitride a-Si3N4 prevailed over the accumulation in crystalline c-AlN layers due to the diffusion of defects in amorphous layers and the formation of secondary defects in them. Changes in optical properties led to the conclusion about the high radiation resistance of the coatings. The main reasons for the resistance of coatings to ion irradiation were the high concentration of growth defects, their strong interaction and the wide band gap of the nitrides. Coatings deposited on silicon substrates had a higher radiation resistance compared to the same coatings deposited on glass substrates.

In this study, particles of titanium dioxide (TiO2) were modified with particles of zinc oxide (ZnO) using a pulsed plasma chemical method, with ZnO initially being obtained by an electrospark method. The particle size of the synthesized TiO2 powder modified with ZnO nanoparticles ranged from 30 to 100 nm. The morphology of the nanoparticles was found to be diverse, mainly represented by spheres, ovals, and parallelograms. The phase composition was a mixture of crystalline phases characteristic of TiO2 (rutile and anatase) and ZnO, with the predominant phase being anatase. The presence of Zn-O-Ti bond is typical for all samples of TiO2 powder modified with ZnO nanoparticles prepared using a pulsed plasma chemical synthesis, which indicates the formation of a solid solution. The optical and photocatalytic properties of the modified nanoparticles were also studied, as well as the band gap was determined. For some samples, a narrowing of the band gap was recorded. The samples showed high photocatalytic activity in the decomposition of methylene blue under the influence of ultraviolet and visible light in the wavelength range of 400-630 nm. Methylene blue degradation efficiency was 66% in visible light spectrum.

The effect of high-intensity short-pulsed ion irradiation on the optical properties of multilayer coatings, consisting from thin layers of aluminum and silicon nitrides, deposited by reactive magnetron sputtering on glass, steel and silicon substrates, has been investigated. The larger the thickness of AlN layers, the stronger the effect of growth and radiation defects on multilayer coating properties. When the concentration of growth defects increases and its interaction intensifies, the radiation resistance of coatings grows. In general, the radiation resistance of coatings was due to the wide band gap of their constituent nitrides and the high concentration of strongly interacting growth defects distributed along the inter-crystallite and interlayer boundaries.