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The paper presents a methodology for experimental research and a test bench for determining the flow coefficient during the flow of a two-phase working fluid through cracks. The dependences of the influence of the degree of dryness of the wet refrigerant vapor and the gap resistance on the flow coefficient during the outflow of the working fluid through the gap were established. A method for determining the coefficient of flow of wet vapor through cracks is proposed, implemented on the basis of the method of S.E. Zakharenko for dry saturated vapor and a correction function for the degree of dryness of the vapor. Artificial refrigerants used in air conditioning systems, such as R32 and R410a, which belong to the HFC class, and R22, which belongs to the HCFC class, are considered as the working fluid.

The problem of redistributing quotas for training among structural divisions of a higher education institution is considered. The problem of redistributing quotas has a wide range of applications, in particular, in preventing environmental pollution. The article assumes that a higher education institution has several structural divisions. The management of the higher education institution allocates some quotas for training to structural divisions (SD). The head of each SD can give part of the quota of his SD to another division, receiving some compensation in return. In this case, if the quota is not given, it must be fully used in the joint venture to which it was allocated. The head of each joint venture strives to maximize his gain, expressed by his objective function. For simplicity, it can be considered that the goal of the head of each joint venture is to maximize the amount of funds accumulated in the centralized fund of this joint venture. In this case, the head of the joint venture can manage the share of the quota allocated to him, which he wants to give or receive from another joint venture. It is shown in which cases all structural divisions manage to receive optimal quotas for them as a result of redistribution. Three cases are considered: when the total value of the quota that the divisions want to give is greater than, less than or equal to the total value of the quota that other structural divisions want to acquire. Algorithms for redistributing quotas in each of these cases are proposed. The study is conducted analytically for a particular type of input functions, which are taken as power functions. Numerical examples are given and an analysis of the results obtained is given. A number of meaningful conclusions are made.

Crystalline magnesium silicates with talc and saponite structures have been synthesized under hydrothermal conditions. Amorphous magnesium silicate has been obtained using the precipitation and sol−gel methods. The influence of the crystalline structure of magnesium silicates on their sorption capacity and surface properties has been studied. The samples have been examined using X-ray diffraction analysis, scanning electron microscopy with EDX analysis, and low-temperature nitrogen adsorption. The moisture absorption capacity of the samples and the functional composition of their surfaces have been investigated. The ability of the samples to remove an antibiotic, ciprofloxacin, from aqueous media has been studied, and adsorption isotherms have been constructed. The Langmuir, Freundlich, and hybrid Langmuir−Freundlich models have been used to approximate the obtained data. The contributions of different mechanisms to the adsorption of ciprofloxacin by the synthesized magnesium silicates have been evaluated. An analysis of the quantitative distribution of acidic and basic sites, as well as the sorption capacity of the samples, has revealed that, for the studied materials, the distribution of the active sites and the sorption capacity depend essentially on the degree of crystallinity of the samples, the structural ordering of their surfaces, and the method of their preparation. It has been found that a decrease in the crystallinity and the transition to amorphous forms, as well as the specific features of the synthesis method leading to the formation of a more developed and porous surface, contribute to an increase in the sorption capacity of the samples.

The reaction involving the production and decay of the ⁸Be* nucleus is examined in the interaction of fast neutrons with an energy above 3 MeV with a ¹⁰B nucleus. The study is conducted using a multidetector setup comprising a position-sensitive neutron detector and a pair spectrometer for electrons and positrons operated at the RADEX neutron channel at the Institute for Nuclear Research of the Russian Academy of Sciences (INR RAS). To this end, events with the emission of a secondary ³H nucleus and a photon are identified along with rare events involving the emission of an e⁺e^– pair. An estimate is obtained for the contributions of transitions of various multipolarities from the excited state of the ⁸Be nucleus to the ground state in the internal conversion of an electron–positron pair.

The use of AX-Offset D90 parabolic mesh offset antennas for studying astrophysical sources, including the Sun, employing the MIFIst radio interferometer, is discussed. The latter is a detector system based on antenna complexes with an unfilled aperture with a total size of ~ 450 m, which will provide an angular resolution of ~5.70 × 10⁻³°, ~2.60 × 10⁻²°, and ~0.12° at frequencies of 6.5000, 1.4204 (HI line), and 0.3000 GHz (z ~ 3.7 for the HI line).

Six previously undescribed compounds, together with twelve known compounds, were isolated from Sinomenium acutum. The structures of the unreported compounds were determined by comprehensive spectroscopic data analysis, ¹³C NMR calculations followed by DP4 + analysis, ECD calculations, and single-crystal X-ray diffraction analysis. Nine compounds exhibited more potent anti-inflammatory activities than the positive control indomethacin. The structure-activity relationship of the isolates with anti-inflammatory effects was elucidated, providing some useful clues for designing and developing structurally novel anti-inflammatory drugs. Furthermore, five compounds reversed the paclitaxel resistance in paclitaxel-resistant cervical cancer cells HeLa/PTX. The combination of compound 4 and paclitaxel promoted cancer cell apoptosis.

We investigate the spatiotemporal dynamics of aerosol pollution in the Indo-Gangetic Plain (IGP) and the North China Plain (NCP), two of the world's most populated regions, against their anthropogenic emissions. Utilizing CAMS EAC4 reanalysis, CAMS-GLOB-ANT emission inventories, and ERA5 meteorological data for the year 2019, we analyze the seasonally changing relationship between PM-forming emissions and ambient PM_2.5 concentrations. We find a significant disparity: despite the NCP emitting 65% more total anthropogenic particulates and precursors annually (28,860 KT vs. 17,464 KT), the IGP suffers higher annual average PM_2.5 concentrations (123.6 vs. 113.2 µg/m3). Temporal and episode analyses reveal that large swathes of both regions are engulfed in polluted air during much of the year, with some respite during the summer and monsoon seasons. The NCP, with lower annual average PM_2.5, records more total "bad air quality" days (251 vs. 238), while the IGP is characterized by fewer but more prolonged episodes, with extreme stagnation events in the Delhi region lasting up to 170 consecutive days. To quantify the regional contrast in atmospheric response, we introduce the "Pollution Forming Efficiency" (PFE) metric. Our results show that during winter, the IGP's PFE is nearly double that of the NCP, meaning that the IGP atmosphere converts unit emissions into ambient concentrations far more effectively. We identify regional meteorology as the primary driver; the IGP is characterized by stagnant winds (< 6 km/h) and a shallow planetary boundary layer (< 300 m) leading to a consistently lower ventilation coefficient that inhibits vertical mixing and dispersion of pollution. Ultimately, our findings reveal that there is an inherent meteorological vulnerability to the IGP, and therefore, any economic growth strategy in this region must account for its limited carrying capacity. Recognizing that the IGP atmosphere uniquely amplifies the health impact of every kilogram emitted is the first step toward securing a breathable future for the more than one billion people who call these plains home.

The creation process and key characteristics of the prototype of the main antenna module within the MIFIst radio interferometer were discussed. The AX-Offset D90 parabolic mesh offset antenna was selected as the module element. The setup is characterized by its mobility, compactness, reduced shadowing of the useful reflector area, and the use of available components, simplifying system assembly and scalability.

The current status of the Baksan Large Neutrino Telescope project is presented in this work. The results of the first stage—a prototype with a target mass of 0.5 t—were described. The main improvements in the second prototype were also outlined: the magnetic field compensation system and the liquid scintillator purification system.