The present study considers a linear control system with a periodic matrix of coefficients and program control. The matrix under control is constant, rectangular, and its rank is not maximum. It is assumed that the control is periodic, and that the modulus of its frequencies, i. e. the smallest additive group of real numbers, including all the Fourier exponents of this coefficient, is contained in the frequency modulus of the coefficient matrix. The following problem is posed: to select such a control from an admissible set that the system would have periodic solutions, the frequency spectrum (the set of Fourier exponents) of which contains a predetermined subset, and the intersection of the modules of the frequencies of the solution and the matrix of coefficients is trivial. The posed problem can thus be termed the ‘problem of control of the asynchronous spectrum with the target set of frequencies’. The solution to the posed problem essentially depends on the structure of the average value of the matrix of coefficients. To date, this problem has been solved for systems with zero mean. In addition, the case is studied when the matrix under control has zero rows, the averaging of the matrix of coefficients has a degenerate left upper diagonal block, and the rest of its blocks are zero. The question for a system with a nontrivial right lower averaging block remained open. In the present work, we study the problem of control of the asynchronous spectrum for the indicated class of systems. It has been established, in particular, that for the solvability of this problem it is necessary that the block formed by the rows of the matrix of coefficients has an incomplete column rank.

The present study investigates the impact of high-pressure synthesis on the magnetic properties of 314-related Sr0.8Eu0.2Co1–xZnxO3–d (x = 0; 0.05) cobaltites. The observed magnetic behavior is driven by an increase in oxygen content, leading to the formation of a significant number of Co4+ ions. This results in enhanced ferromagnetic interactions through Co4+–O–Co3+ exchange and/or the emergence of superparamagnetic clusters below TC, attributed to electron transfer between IS Co3+ and LS Co4+. These findings highlight the role of oxygen stoichiometry in tuning the magnetic properties of perovskite-related cobaltites.

The structure and physicochemical properties of scaffolds obtained from acetate extracts of fibrillar collagen from the tendon membranes of Wistar rats have been the subject of study. The synthesis of a film-like scaffold at 37 °C and a volume scaffold at 6 °C was conducted. Scaffolds of both types are structured into glomerular and extraglomerular fractions. The volume ratios of fractions are determined by the influence of temperature on the kinking of collagen fibers. At 37 °С, kinking is suppressed, and a fraction with initially straightened fibers – the extracellular framework of a filmy scaffold – is formed. At 6 °С, kinking increases, and the growth of a fraction with initially twisted fibers – tangles of a volumetric scaffold – is accelerated. The typogenesis of hydroxyapatite is determined by the microstructure of the scaffolds and the direction of development of transpiring structures. Stoichiometric hydroxyapatite is synthesized in dominant water-evaporating fractions, while carbonate hydroxyapatite is synthesized in subdominant water-retaining fractions. The relationship between kinking and the strength of the peptide chains of fibrillar collagen is characterized by an inverse interdependence. Specifically, when kinking is weakened, the peptide chains are strengthened, and when kinking is strengthened, they are softened. Carbonate substitutions are sensitive to the temperature of scaffold synthesis. At 37 °C, CO₃^2– anions replace OH^–, and at 6 °C, PO₄³⁻ groups replace them. The comprehension of the mechanisms underlying the structuring of calcium phosphates on matrices of fibrillary collagen is essential for the design of collagen-apatite-based scaffolds with predefined functional properties.

Chicken breeding facilities generate substantial quantities of chicken manure during their operation. Consequently, the processing of organic waste from these facilities is a pressing concern. In this work, a study was conducted on the selection of the composition of chemical reagents for processing chicken manure for the purpose of its subsequent use in the production of complex fertilizers. Research has demonstrated that a composition comprising ammonium persulfate, formaldehyde, and peracetic acid, as well as a composition containing sulfuric acid, sodium hypochlorite, sodium hydroxide, and lime milk, have a deodorizing effect on chicken manure in both laboratory and industrial conditions. From the standpoint of the rapidity with which the deodorizing effect is initiated, a formulation comprising ammonium persulfate, formalin, and peracetic acid is preferable. The deodorization effect was observed in 100-liter litter samples after a treatment period of 40 minutes. Both compositions demonstrated effective retention of their deodorizing and disinfection properties over a duration of up to 30 days. The utilization of chicken manure in this manner does not constitute a threat to the environment and can be used as an organic component of complex organomineral fertilizers.

The article presents the results of a study of the genetic diversity of Liparis loeselii (L.) Rich. populations using molecular iPBS markers. Samples for analysis were selected from six populations located at the southern border of the species’ range in the Grodno, Minsk, and Vitebsk regions of Belarus. The findings indicate that higher levels of genetic diversity are associated with populations that exhibit larger areas, greater numbers of plants, and potentially older ages of the population itself. The predominance of intrapopulation genetic diversity (74 %), as well as a low level of gene flow, indicate that genetic drift significantly affects the formation of the genetic structure of L. loeselii. The obtained data generally indicate a low adaptive potential of L. loeselii. Сonsequently, an unfavorable forecast for its conservation in the wild is provided, taking into account the current climate dynamics, as well as successional changes occurring within the bog biotopes.

Physiological studies were conducted to confirm the functional properties of new types of meat products intended for the nutrition of primary school children with an elevated body mass index. The recently developed high-quality meat products used in this study had reduced caloric content, with energy values 30 % lower than traditional products for primary school children, and no specific additives were present while maintaining product quality and appeal. The experiment revealed distinctive changes in parameters such as exploratory and locomotor reflexes, coordination, and endurance. A complete blood count and biochemical analysis were performed, and the metabolic activity of bifido- and lactobacteria in the large intestine was analyzed and evaluated both in physiological normalcy and after diet modification. The findings indicate that dietary correction is sufficient to initiate positive dynamics in counteracting adverse changes in the body caused by excessive consumption of high-calorie food.

Mesh filter materials are widely used in the filtration of gases and liquids solid inclusions, exhibiting numerous advantages, including high strength, permeability, and heat resistance, as well as the capacity for multiple regeneration. However, a notable disadvantage is their limited dirt capacity, which consequently results in a reduced service life prior to regeneration. Simultaneously, the regeneration process is challenging. It is not feasible to entirely eliminate all the dirt particles that have become embedded within the cells. Additionally, the cells themselves are susceptible to deformation. The filtering material with orthotropic structure on the basis of woven meshes (FMWM), consisting of woven meshes package, is devoid of these disadvantages. The FMWM demonstrates superior dirt capacity due to its operation in depth filter mode. Furthermore, the channels where the pollutant particles are retained can be completely cleaned during the regeneration process with the filter disassembly. In summary, FMWM possesses a practically infinite operational lifespan. The most preferred method for recycling FMWM is by reusing material resources, a practice that eliminates environmental problems during processing. The rational design of FMWM products is based on establishing a relationship between structural parameters and material properties. In the presented work, the problem of forecasting and FMWM performance properties optimization on the basis of mathematical models of the structural parameters’ relationship with technological characteristics and properties at limited variation possibilities by controlling factors is solved.

The paper presents the results of modeling the process of homogeneous nucleation of silicon dioxide vapors. The purpose of the modeling is to improve the understanding of the operating features of a high-temperature stand. The nucleation process is described as a result of a triple collision between two molecules of silicon dioxide and any third molecule in the gas mixture. It has been demonstrated that at high vapor supersaturations, nucleation exhibits a significantly non-isothermal character. The formation of more than 1021 clusters per cubic meter is observed. The release of latent heat of the phase transition significantly increases the temperature of the gas mixture (by hundreds of degrees Kelvin). It is found that the higher the vapor supersaturation, the smaller the quasi-steady radius of nanometer clusters. This effect influences the Brownian deposition of clusters on the substrate.

Based on the results of a republican sociological study conducted by the Institute of Sociology of the National Academy of Sciences of Belarus in 2024, in which the author participated, the main social determinants of the distribution of digital technologies in the everyday practices of residents of Belarus were identified: 1) new opportunities that facilitate and speed up routine operations, as well as simplifying inclusion in educational processes; 2) high-tech and flexible forms of employment with significantly more comfortable working conditions; 3) effective means to help implement self-preservation behavior; 4) diverse and accessible forms of free communication; 5) convenient and fast ways to receive numerous services, including financial ones. The aforementioned supra-professional skills of social subjects, including retraining skills, adaptability, determination, independence, and the ability to assess risks, constitute a competency factor that provides the basic enabling conditions for the development of digital technologies

Rhizosphere bacteria Bacillus, preserved in the of the Institute for Soil Science and Agrochemistry, were characterized as promising plant inoculants under intensive application of herbicide glyphosate. Bacteria strains Bacillus K-32, K-54, K-62, K-65, K-81, and Kт were found to metabolize glyphosate without the formation of aminomethylphosphonic acid. Bacteria strains Bacillus K-32, K-54, K-62, K-65, K-81 and Kт are capable of glyphosate decomposition with the formation of safe chemical products. These chemical products include sarcosin (methylglycine) and inorganic phosphate (Pi). The destruction activities of Bacillus strains were calculated on the basis of the accumulation of inorganic phosphate in culture liquids. Under glyphosate concentration of 300 mg/l, the destruction activities of Bacillus K-32, K-54, K-62, K-65, K-81, and Kт strains were equal to: 50.6, 43.9, 48.4, 46.3, 65.4 and 64.4 %, respectively. Under glyphosate content 500 mg/l, the destruction activities were equal to: 40.6, 38.6, 40.1, 42.2, 58.4 and 48.1 % respectively. The application of potassium-mobilizing rhizobacteria Bacillus as inoculants resulted in a significant stimulation effect on plants at high diapason of glyphosate content in the soil (0–50 l/ha). This stimulation effect is manifested in plant growth (stems and roots) and the improvement of plant potassium nutrition.