Home – Home – Jornals – Scientific journal “Vestnik NSUEM” 2025 number 2

Quantitative analysis of the gas mixture absorption spectra is complicated by noise. The parameters of standard filters are related to the entire analyzed spectral range. This means that the filter parameters being optimal for strong absorption lines are not optimal for weak absorption lines and vice versa. An approach to create adaptive filter for denoising experimental spectra based on the combination of a windowed version of a standard filter with the independent component analysis is suggested and implemented with the Savitzky-Golay filter as an example. The numerical simulation was carried out at normal conditions for the absorption spectra of the model of mid-latitude summer atmosphere in the 100-1000 GHz spectral range. The efficiency of the suggested adaptive and the standard versions of Savitzky-Golay filter was compared using a quantitative criterion of the proximity between two spectral curves. Experimental validation of efficiency of the suggested adaptive Savitzky-Golay filter was conducted on the example of 200 ppm SO₂ and 10000 ppm H₂O gas mixture. The SO₂ concentration was evaluated using multivariate curve resolution method. The relative error in the concentration retrieved after noise reduction by this filter was 3.7 times less compared to the standard Savitzky-Golay filter. Thus, the suggested adaptive Savitsky-Goley filter makes it possible to increase the efficiency of noise suppression in experimental spectral data.

The paper presents the results of calculating 10 the lowest vibrational energy levels of all 24 stable sulfur dioxide isotopologues. The calculations were performed using the ab initio potential energy function of the main isotopologue ³²S¹⁶O₂, the Rayleigh-Schrödinger perturbation theory of high orders and the Padé-Hermite series summation method. A numerical analysis of the series was performed, which showed that the perturbation series monotonically converge, but to obtain the energy levels of some vibrational states with an error of less than 1.0 cm^-1, it is necessary to take into account the corrections of the 3rd-6th orders. The quadratic Padé-Hermite approximants give energy levels that coincide with high accuracy with the results of numerical diagonalization of the Hamiltonian matrix. A correction is proposed for calculating isotopic shifts, which gives a root-mean-square coincidence of 1.1 cm^-1 with the experimental and calculated data by other authors. The calculation results can be used to solve various problems of atmospheric spectroscopy, astrophysics, geochemistry, and other fields of science related to the analysis of spectra of isotope-substituted molecules.

Atmospheric turbulence is one of the most significant factors affecting the propagation of waves of various nature and the operation of devices based on their application. The paper presents the results of experimental studies of the impact of short-term heavy rainfall on subsequent changes in the meteorological and turbulent state of the ground atmosphere based on processed synchronous acoustic and optical measurements of atmospheric parameters. An assessment is made of the impact of intense precipitation on the main turbulent characteristics of the surface atmosphere, such as the energy of temperature and wind fluctuations and vertical heat and momentum fluxes. It is shown that heavy rainfall significantly changes these characteristics. The results can be used to interpret optical and acoustic measurements used to study the atmosphere.

Observations of the state of the mesosphere of Venus from spacecraft have not yet revealed transient luminous events similar to those observed in the Earth's atmosphere. In this work, a possibility of such phenomena is proved in laboratory conditions. For this purpose, an experiment was conducted on the formation of apokamps in carbon dioxide at various pressure values. The results confirm the hypothesis that conditions at altitudes corresponding to the upper edge of clouds in the atmosphere of Venus are favorable for the generation of analogues of transients of the Earth's mesosphere. Based on this, recommendations have been developed for the design of detection systems for such phenomena from orbiting satellites or balloons.

Based on a developed and adapted method for identifying Rossby wave breaking (RWB), which accounts for the specifics of stratospheric circulation, an analysis of the conditions for the occurrence of major sudden stratospheric warmings (SSWs) in the Northern Hemisphere was conducted. The method relies on examining the geometry of potential vorticity contours in the stratosphere at the 850 K level using ERA5 reanalysis data. It is shown that anomalous RWB processes in November and December play a key role in preparing for the onset of SSWs. Most of the analyzed SSW events are associated with an increase in the number of RWB events in the Asia-Pacific (AP) region in November and December, and occasionally in January. In cases where SSW initiation is linked to RWB over the Atlantic and Europe, it is also preceded by RWB anomalies in the AP region. For the identified types of wave breaking in the stratosphere, atmospheric blocking is characteristic in the troposphere, accompanied by negative near-surface temperature anomalies over Eurasia and/or North America. The increased frequency of early and middle major SSW events aligns with the previously identified trend of enhanced negative temperature responses to atmospheric blocking in the Northern Hemisphere.

The development of the deep underwater neutrino telescope BAIKAL-GVD involves the creation of equipment for regular long-term monitoring of inherent optical properties (IOP) of the aquatic environment within the effective volume of the telescope. Regular monitoring of IOP not only allows increasing the accuracy of retrieving neutrino energy and direction, but also provides unique data for limnological studies. The article describes the design of the BAIKAL-5D devices developed to solve this problem and considers the methods and algorithms for in situ monitoring of IOP used in these devices. The sources of instrumental error in measuring the absorption and scattering of light in water are investigated and the necessary corrections are determined. Some results of measuring IOP of the deep waters of Lake Baikal using BAIKAL-5D devices are presented.

This paper demonstrates for the first time the possibility of exciting anti-Stokes fluorescence of PO-fragments of organophosphates. Using the example of drop-liquid traces of triethyl phosphate on a paper surface, it was determined that the relative population of vibrational levels v '' = 1 and v '' = 2 corresponds to a vibrational temperature of fragments of about 780 K. Indicators of significant violation of the equilibrium distribution of fragments over rotational energy levels were revealed. It has been determined that the method of exciting anti-Stokes fluorescence of PO-fragments of triethyl phosphate from the first vibrational level of the ground state X ²Π ( v '' = 1) to the zero vibrational level of the electronically excited state A ²Σ⁺ ( v ' = 0) provides the highest noise immunity of the LF/LIF method. The results can be used to select the optimal technique for exciting fluorescence of PO-fragments when implementing the LF/LIF method for remote detection of organophosphate traces.

The paper is devoted to research of the output signal composition of metal-vapor laser active optical systems under various operating conditions. The effect of the temporal characteristics of laser active optical systems on the output signal composition is experimentally estimated. The method for determining the contribution of amplified spontaneous emission (ASE) to the output signal of self-adjoint scheme and scheme with independent illumination source is suggested. The optimal time when input signal enters to active medium of amplifier for providing maximal signal/noise ratio is determined. ASE is completely suppressed at a time delay of (-4.3; +25.8) ns in the scheme with independent illumination source. It is impossible to achieve complete suppression for the self-adjoint scheme. The minimal ASE value in the self-adjoint scheme was 80 mW, i.e., approximately 2% of the output signal power. The results can be useful in researching the amplification characteristics of active optical systems based on metal vapors, as well as in visual-optical diagnostics in laser monitor circuits on their basis.

This paper considers the problem of classifying cloud images, which are complex texture structures with heterogeneous characteristics. Traditional image analysis methods do not always adequately classify such images, and modern deep learning methods require large amount of data and computational resources. The research focuses on evaluating the feasibility of developing a hybrid method combining traditional statistical approaches to texture description and state-of-the-art deep learning techniques. It was hypothesised that the high-level features extracted by a neural network during training can be insufficiently sensitive to subtle local differences in cloud formations. The hybrid approach was implemented and analysed; low-level texture features were extracted from the images before being analysed by the neural network. However, the test results showed that this technique did not improve the classification quality and turned out to be less effective in terms of accuracy compared to the use of unprocessed images. The results of this work can be of interest to specialists in of Earth remote sensing data analysis, meteorology, and development of new texture image analysis methods.

Experimental data obtained in the surface air layer at two observation sites with the underlying surface different in structure are used to estimate the Monin-Obukhov (MO) scale for different types of temperature stratification. The MO scale (its sign, first of all) is compared with the current temperature profile in the surface air layer. It is shown that the sign of the MO scale not always corresponds to the actual temperature stratification.

Carbon dioxide (CO₂) is one of the main greenhouse gases; the study of its effect on the atmosphere on global and regional scales is of current importance. The development of technical means for remote gas analysis of the atmosphere is associated with the development of new and modernization of existing lidar sensing technologies. The paper presents the results of the development of a 2-μm pulsed differential absorption lidar system for sensing CO₂ along horizontal paths in the atmosphere. The configuration and design of the lidar components are shown. Technical characteristics of the lidar system are provided. The results of lidar measurements of the time variation in CO₂ concentration within the city of Tomsk in winter along a selected sensing path using a topographic target (forest belt) are presented. CO₂ concentrations in the range of 435.2-445.1 ppm, corresponding to the background state of the atmosphere, were retrieved from recorded lidar signals. To confirm the correctness of the lidar data, the CO₂ concentration was synchronously measured using a mobile gas analyzer. Analysis of the results shows that the error of lidar measurements of the CO₂ concentration is 1.3%. The results of the work can be useful in the design, manufacture, and modernization of pulsed IR lidar systems for remote sensing of CO₂ and other atmospheric gases.

Corporate strategic communication is important to sustainable development of contemporary business and its effective interaction with society. The aim of this research is a study of priorities and traditional values in strategic statements on official web-pages of large companies from a particular region. The Vologda Region is chosen as a test site for present pilot research. The material for this analysis consists of 20 strategic statements of the large companies from the Vologda Region. Their content is analyzed, first, with the Pearson-David palette permitting to check presence/absence of key priorities (customers, image, employees, etc.) and, second, via finding specially grouped traditional values of the Russian society (Motherland, labor, society, etc.). According to the results, the large companies considered state several priorities, among which the most common is products/services, and the least common is employees. Also, we find in the studied strategic statements all groups of traditional values (commonly, one-three per statement), among which the higher frequency is typical for society, labor, and traditions, and the very low frequency characterizes family. These results indicate a significant maturity of strategic communication between large companies from the Vologda Region. We suppose an influence of the regional specifics on the peculiarities of the interaction between business and society. The carried-out study contributes to the conceptual argumentation of a phenomenon of regional social partnership and the detection of peculiarities of its formation and development.

Modern problems in the field of formation of conscious safety behavior of future graduates of higher school are considered. The process of building a system of formation of conscious attitude to occupational safety and health regarding age specifics is visualized. As one of its stages it is suggested to introduce a practice-oriented discipline ‘’Occupational Health and Safety‘’ in higher e ducation institutions. Occupational safetyand health competences that a young worker should possess are formulated. A new formulation of the universal competence UK-8 is proposed, and a new competence UK-12 is formulated, which makes it possible to form informed safe behavior in a future worker.

This article examines the impact of green projects on the Gross Domestic Product (GDP) of the Kyrgyz Republic using correlation-regression analysis. Based on GDP data for 2010-2024, the volume of green loans, investments in fixed capital aimed at environmental protection, state budget expenditures on environmental protection, corporate expenditures on environmental measures, and the share of fixed capital investments dedicated to environmental protection, a mathematical model has been developed. A forecast of GDP dynamics up to 2035 was constructed, demonstrating stable economic growth under conditions of continued development of green initiatives. The findings underscore the importance of sustainable financing for Kyrgyzstan’s long-term economic development, as well as the necessity for governmental support and the attraction of private investments.

The article proposes the use of intellectual information support for decision making in the process of forming a securities portfolio based on knowledge engineering, the feedback principle and adaptation of risk assessment models. The structural diagram of the system for managing the process of forming a securities portfolio is considered, which includes three circuits - regulation, adaptation and training. It has been established that the systematic approach allows us to consider the process of forming an investment portfolio in the context of the current actual situation, real financial results, and cognitive characteristics of the investor. The results of a computational experiment conducted using historical data on securities quotes are presented, which, in comparison with a benchmark, showed that the use of intellectual information support can improve the efficiency of decisions made.

A method of predicting revenue based on a sustainable growth model, taking into account the change in the cost of borrowed funds, prices for products and means of production, has been proposed. The stochastic modification of the model is used, taking into account economic uncertainty. The forecasting horizon is limited to the period specified in the annual accounting reporting. The described method of forecasting does not have a long memory, so the resulting result is not tied to the previously prevailing trend. To take advantage of the new approach, time-intensive calculations and special training will not be required.

The object of research in the article is large manufacturing and technological companies of discrete production; the subject of study is internal prices and approaches to their determination, which significantly affect the economic performance of the system. For an adequate description of the functioning of the system, matrix modeling based on the methodology of the MOB is proposed. Economic and mathematical models, including the conditions of supply and demand, are used as tools for the interaction of the system’s firms with other firms in the market. The scenarios of the system functioning are considered, approaches to the formation of internal prices and their impact on the economic indicators of the system are proposed. Based on such dependencies, it has been established that the choice of an option for domestic prices can be made only when taking into account the values of a number of economic characteristics of the system, ordered by importance. A variety of internal price options for management decision-making is provided by the developed toolkit (a generator of internal price options). The final decision on the choice of an option for domestic prices in the context of several criteria is made by the LPR for reasons of economic expediency.

Maintaining auditor independence from the client is fundamental to enhancing the reliability of financial reporting, preventing conflicts of interest, and strengthening investor confidence in the capital markets. Various international frameworks, including the International Code of Ethics (IESBA) and International Standards on Auditing (ISA), have attempted to strengthen auditor independence and professional skepticism, but their application varies widely across jurisdictions. This study provides a comparative analysis of international standards governing the auditor - client relationship and assesses how different jurisdictions interpret, apply, and adapt the global audit framework. The study examines the contrast between the PCAOB’s enforcement mechanisms, pre-established EU regulatory constraints, and the IESBA’s flexible threat and protection approach, demonstrating how these mechanisms interact with national legal traditions, institutional oversight, and economic incentives. In addition, the study considers the significant impact of technological change on audit processes. The study concludes by offering policy recommendations for harmonizing global auditing rules, balancing the need for standardization with the flexibility of jurisdictions to accommodate economic and legal realities. This study contributes to the ongoing debate on global audit standardization by highlighting the need for a dynamic regulatory framework that can evolve with financial markets and technological innovation, ensuring that the audit profession remains a reliable guardian of financial integrity.

In recent decades, an information boom has arisen around the concept of “biodiversity” in the “whirlpool” of environmental aspects and problems. A negative consequence of its wide popularity has been the vagueness of the semantic content and the shapelessness of the construction of the beloved concept. This has complicated the mutual understanding of specialists in scientific and everyday ecology. Clarifications of the definition of the concept of “biodiversity” and the scope of its use, structuring and connection of its object of interest with evolutionary theory are urgently needed. For this purpose, an ordered system of four structural categories of biodiversity is proposed, embodying the evolutionary potential of the population-species, biocenotic, biogeocenotic and biosphere levels of life organization. The categories of biodiversity are designated by symbols: alpha, beta, gamma, sigma biodiversity. Their emergence and long-term existence are due not only to the complex configuration of ranges that arose due to the capabilities of the biota, but, to a greater extent, to the structural features of the abiotic matrix of the external environment. First of all, modern runoff-water-collecting continental-oceanic and relict basins that have lost their former connection with the World Ocean are important. Such megahabitats, clearly delimited from each other by orographic, hydrological, climatic barriers, contribute to isolation and provide biota with the opportunity to freely choose a set of environmental conditions. However, not all biological species can use them, but only those with a suitable set of preadaptations, capable of getting along with each other and stereotypically reproducing a standard set of biota over a long period of time. Attention is focused on biogeocenoses and their catenary compositions - grandbiomes, confined to heliozones of latitudinal extension and their derivatives - climatic, soil, landscape zones. Biogeocenoses and grandbiomes, as elements of gamma-biodiversity, unlike the previous categories, have the ability to involve in their contact not only living but also inert matter, guaranteeing the transformation of an uncomfortable weathering crust into a comfortable living environment, regulated by the biota at its own discretion. Each evolutionarily subsequent category of biodiversity did not destroy or suppress the previous ones, but mutually incorporated them into its structure. Such a construction resembles a series of nesting dolls, which multiplies the stability of the biodiversity system and its potential, guaranteeing a long-term prolongation of life in time and ubiquity in space of the earth’s surface.

The specifics of Norilsk industrial district (NID) soils are abnormally high natural concentrations of heavy metals (HM), in particular Ni and Cu. In such conditions, the additional intake of pollutants into soils with high acidity reduces the stability of soil microflora, and increases the risks of vegetation death. In previous decades, the negative impact of dust and aerosol emissions from industrial enterprises of the NID containing SO2, Ni and Cu on the state of soils and the accumulation of HM in vegetation was revealed. The purpose of this study is to assess the current state of soils and vegetation within the impact zones of enterprises of the NID of various types and to identify the degree of their influence. Using the example of three environmental transects, the impact of prolonged aerosol dust and single contact chemical pollution, as well as mechanical transformation in the construction area of industrial facilities, is estimated. The effect of dust and aerosol pollution was recorded on all transects, two of which showed the highest values of the degree of anthropogenic transformation of vegetation (0.5-1). The most negative impact is observed in areas where contact chemical contamination is superimposed on dust and aerosol pollution. The factor of contact chemical impact, in addition to changing the substantial composition and properties, leads to a change in soil profiles. The factor of mechanical transformation has a noticeable effect on both the composition of phytocenoses and the soil profile. At the same time, the content of HM in this transect does not exceed the values corresponding to the geochemical background. The restoration of vegetation and soils in such areas begins immediately after the ending of mechanical action.

The possibility and prospects of using spiders (Arachnida: Aranei) as a bioindicator of the degree of anthropogenic impact in the Norilsk industrial region was investigated. Soil-dwelling spiders were collected using pitfall traps at the sites of three transects: Kayerkan, Norilsk and Talnakh, located in the vicinity of the city of Norilsk at different distances from large industrial facilities. A total of 119 spider species were found. The richest in species were the sites of the Norilsk transect, where 71 species were collected. A significant Spearman rank correlation between the distance from the industrial facility and the diversity parameters of taxocenes was noted mainly for the sites of the Kayerkan transect in 2022 and 2023. The direction of this transect largely corresponded to the prevailing wind direction in the Norilsk region. The taxonomic diversity of spiders on this transect is also the lowest. The total number of species, diversity indices, as well as the number of species and individuals of Linyphiidae spiders and the ratio between the number of Linyphiidae and wolf spiders (Lycosidae) individuals were positively correlated with the distance from the plant. In 2023, only the last parameter significantly depended on the distance. For the Norilsk transect, the correlation of the dynamic density of spiders with the distance from the plant was statistically significant only in 2022. Ordination by the method of non-metric multidimensional scaling for the sites of the three studied transects in different years showed that the differentiation of the sites, firstly, corresponded well to the habitat differences of the study sites on all transects; secondly, the study sites were better differentiated before the onset of phenological summer and the associated increase in temperatures and the complete formation of different vegetation layers. It has been established that soil-dwelling spiders can be used as indicators of negative impact, while it is extremely important to conduct research in similar habitat conditions, minimizing their differences as much as possible. When analyzing, it is imperative to take into account the features of seasonal dynamics and the impact of interannual fluctuations in climatic factors.

The study addresses species diversity of phytoplankton, zooplankton, and zoobenthos in twenty-eight Arctic lakes located in the Taimyr Peninsula within a radius of about 100 km from the city of Norilsk. The aim was to compare biodiversity between four zones defined based on a lake distance from Nornickel facilities: the zones of intense, moderate, and low impact (ZII, ZMI, and ZLI, respectively), and the reference zone (RZ). Beta diversity analysis based on the Bray-Curtis dissimilarity index did not reveal any significant differences between lakes in ZII and the other zones. Planktonic and benthic community structures alter substantially only in six lakes located in close proximity to the industrial area. In other lakes, the changes are less pronounced and their community compositions are likely determined by natural factors rather than the level of anthropogenic impact. Significant differences between zones were revealed for the average number of species and Shannon index: both indicators were significantly higher for zooplankton in lakes of RZ and ZLI compared to ZII and ZMI and for zoobenthos in lakes of ZMI compared to ZII lakes. Significant differences in biomass were observed only for phytoplankton: in ZII, it was higher than in ZMI. Therefore, the number of species, Shannon index, and biomass should be considered in addition to changes in species composition when determining the extent of industrial impact on planktonic and benthic communities. Alterations of plankton and benthos community structures noted here are similar to those observed under eutrophication of a water body.

Quantitative studies and observations of seabirds and mammals were carried out in the NSR section (Dudinka-Murmansk). The entire route was divided into three segments - the Yenisei River and the Yenisei Bay, the Kara Sea and the Barents Sea. 34 species of birds belonging to 5 orders and 5 species of marine mammals were noted. The density of seabird distribution in summer on the NSR transects was highest in the mouth of the Yenisei, the Yenisei Bay (9.96), and the Barents Sea (8.02). In the autumn period, it was much higher in the Kara Sea (43.5) than in the Barents Sea (13.3) and in the mouth of the Yenisei and the Yenisei Bay (6.28 ind./10 km). The vessel attracted such species of gulls as Kittiwake, Glaucous Gull, Great Black-backed Gull and Herring Gull, which followed on it up to 1000 km. The main distance is the response of Ringed Seal to the movements of the vessel is 100-300 m. It is recommended to avoid passing vehicles in places where seals congregate than 500 meters. Monitoring of seabirds and mammals should be carried out in the form of periodic (seasonal) estimates of animal abundance.

The article presents the results of the study of soil properties and composition, as well as species diversity of plant coenoses in areas located at different distances from the enterprises of the Kola Metallurgical Company (KMC) in the Monchegorsk city and Nickel municipal settlement. The impacted areas were found to have maximal concentrations of Ni, Cu, Co. The ratios of soil mobile Cu and Ni to Ca and Mg in the organogenic topsoil horizons indicated their phytotoxicity. The plants in such areas showed morphological signs of acidic damage, their species diversity being minimal. High soil content of Ni, Cu, Co, Cr was suggested to be resultant not only from the technogenic contamination, but also by the natural geochemical anomalies above the ore deposits, as the GMC enterprises are located in the vicinity of such deposits. Technogenic geochemical anomalies had developed near the GMC enterprises; soil Ni, Cu, Co, Cr content and mobility were shown to decrease with increasing distance from the enterprises, whereas plant species diversity increased. Some weak and confounding correlations were revealed between plant biodiversity and soil properties, the correlation being statistically significant for soil Cu and Ni.

Biologically active compounds in ethanol extracts of the leaves of Betula pubescens ssp. czerepanovii were studied in the zone of influence of Nornickel enterprises (Kola Division). The total content of phenolic compounds, flavonoids, tannins, phenolic acids, and photosynthetic pigments (chlorophyll and carotenoid) was determined by spectrophotometry and anti-radical activity was evaluated. The phenolic compound content has increased under anthropogenic stress, indicating that these compounds can be used for monitoring and diagnosing environmental conditions. The plant response to stress was more pronounced for catechins and the total content of phenolic compounds, whose concentration in the zone of maximum exposure increased by 1.4-1.7 times compared with the background. The content of photosynthetic pigments (chlorophyll, carotenoid) in birch leaves decreased by 1.5-1.9 times as they approached the source of contamination. Water-ethanol extracts of birch leaves from polygons in proximity to the industrial facilities of the enterprise had a higher anti-radical activity (IC₅₀ = 0.07 mg/ml), which may be related to increased catechins content. It was found that the variability of BAS content in the leaves of B. pubescens ssp. czerepanovii decreased in a gradient of anthropogenic pollution.

Due to their high sensitivity to changes in habitat conditions, oribatid mites are a promising bioindicator for assessing the state of ecosystem. The article presents the results of the analysis of all available data (2015-2023) on the diversity and biotope distribution of the oribatid mites in the Lapland Nature Reserve, including material from the Great Scientific Expedition organized with the support of PJSC MMC Norilsk Nickel. The generalized taxonomic list of Oribatida of the Lapland Nature Reserve includes 94 species/subspecies from 55 genera and 31 families, of which 17 species were recorded for the first time in this area, and Protoribotritia oligotricha Märkel, 1963 - in the Kola Peninsula. The greatest diversity was recorded for the families Brachychthoniidae (21 species), Suctobelbidae (13), Oppiidae (9), Carabodidae (6), Crotoniidae and Ceratozetidae (5 species each). The oribatid communities studied formed three clusters: ‘forest’ (pine forests and dwarf shrub tundra); ‘tundra’ (lichen tundras); ‘bog’ (cotton-grass sphagnum bog). The oribatid communities of the ‘forest’ group had the highest similarity of faunas among themselves (35-42 %). The lowest similarity of species composition with other oribatid communities was found for sphagnum bog (8-12 %). In monitoring, in addition to the abundance and alpha-diversity parameters of oribatid mites, attention should be paid to the dominance structure and abundance of eurytopic species (Oppiella nova (Oudemans, 1902) and Tectocepheus velatus (Michael, 1880)), which may serve as additional indicators of habitat change. The results obtained are an important step in establishing the basis and in the future forming long-term data series that will allow monitoring the condition of the areas of the Lapland Nature Reserve, identifying and tracking trends.

Helminth fauna of three shrew species of the genus Sorex (Sorex araneus, S. caecutiens, S. minutus) of the Kola Peninsula was studied. Based on our own and analyzed literature data, a complete taxonomic list was compiled, which consists of 21 helminth species: 14 cestodes species of the families Dilepididae, Hymenolepididae and Mesocestoididae, four nematodes species of the families Strongyloididae and Heligmosomidae, three trematodes species of the families Omphalometridae and Brachylaemidae. The greatest diversity of worms in S. araneus was found: ten cestodes species, four nematodes species and three trematodes species. In S. caecutiens seven cestodes species, three nematodes species and three trematodes species were recorded. Eight cestodes species, three nematodes species and three trematodes species were found in the S. minutus. About 80 % of the studied shrews were infected with helminths. A comparative analysis of the helminth fauna of shrews in Eastern Fennoscandia (the Kola Peninsula, Finland and Karelia) was carried out in the direction from the south to the north of the region, in the latitudinal range (59-61°N, 62-65°N, 66-69°N). A high similarity between the quantitative and qualitative composition of the helminth fauna of shrews in the territory of Eastern Fennoscandia (Finland, Karelia, the Kola Peninsula) in the latitude range of 62-69°N (Cj=0.85) was found, which may be due to climatic conditions favorable for the completion of the life cycle of helminths.

The article presents the results of a study of the biological diversity of hydrobionts in the watercourses of the Upper Amur basin, located in the zone of influence of the mining facility of the mining company “Bystrinsky LLC” (BGRK). The Upper Amur Basin is a historical mining region. In addition to the functioning of the BGRK, other mining companies also produce ore and placer gold in this basin. The main studies of the impact of mining on the aquatic ecosystems of the Upper Amur basin are related to the study of the transboundary Argun River. The purpose of the work is to study the biological diversity of hydrobionts of watercourses of the Upper Amur basin, on the example of the Gazimur River, within the zone of possible negative impact of BGRK facilities. Currently, the hydrogeochemical anomaly of the mining area is a factor enriching the hydrochemical state of the aquatic environment. The high migration capacity of Al, As, Sr, Cu, Mn, Zn, Fe, V in the river waters under consideration allows them to accumulate to concentrations exceeding MPC, regardless of the degree of exposure to BGRK. Hydrobiological studies of the Gazimur River and its tributaries have shown that hydrobionts are represented by widespread species of Siberia and the Far East. Seasonal and interannual variations of biota are associated with changes in climatic, hydrochemical and hydrological indicators. One of the possible reasons for the low species richness and extremely low number of aquatic organisms near the BGRK (the Taina and Bystraya Rivers) may be the high turbidity of river water. Based on the results of the conducted research, indicator species of hydrobionts were identified for subsequent monitoring of the effects of mining on aquatic ecosystems.

The properties of the In₂O₃-ZrO₂, In₂O₃-Ga₂O₃-ZrO₂ and In₂O₃-Co₃O₄-ZrO₂ catalysts for the reaction of CO₂ hydrogenation to methanol were studied. It has been determined that with an increase in indium oxide content, the catalytic activity passes through its maximum at In₂O₃ content 10 wt%. It is shown that the introduction of cobalt oxide into the catalyst increases the selectivity for methanol and increases CO₂ conversion. This is due to an increase in the number of oxygen vacancies on the surface of the catalyst. Promotion with gallium oxide, on the contrary, leads to a decrease in activity in the methanol synthesis reaction. Among the series of catalysts studied, In₂O₃-Co₃O₄-ZrO₂ exhibits the greatest activity, which achieves 11.1 % CO₂ conversion with 71 % selectivity to methanol at a pressure of 40 atm and 300 °C. It is also shown that this catalyst operates without a loss of activity for 30 h under these conditions.

The effectiveness of protection and rational use of water resources is reduced due to the difficulties of assessing their quality under the conditions of continuously changing controlled indicators and the uniqueness of such variability. The possibility of solving the arising problems by applying multivariate statistical methods of control, which are common in solving chemometric problems, is considered. By the example of the analysis of the Isakovskoye Reservoir waters (Lugansk People’s Republic), the influence of annual peaks of some pollutants on the increased volatility of the investigated time series was found. The double Schuchart control charts and cointegration tests allowed us to identify the periods of statistical stability of the process and to make an assumption about the active involvement of water pollutants in physical-chemical-biological processes. In particular, the existence of stationary linear combinations of a number of non-stationary (integrated) time series of controlled indicators has been found. The results obtained in the case study of a particular water body show that the methods of chemometrics offer opportunities to obtain the information for deeper understanding of the unique processes occurring in water bodies. This will make it possible to solve one of the main tasks of water-environmental management - to achieve a balance between the needs of water users and the possibility of water resources reproduction by taking optimal water management decisions depending on the current situation.

The content of phenolic compounds (flavonols, flavans (catechins), tannins), polysaccharides (pectins, protopectins), tetraterpenes (carotenoids), as well as the antioxidant and antiviral activity of Solidago canadensis L., Solidago virgaurea L., Bellis perennis L., cultivated in West Siberia has been investigated. The leaves and inflorescences of S. canadensis and S. virgaurea contain about 2 % of flavonols. The total tannin content varies in the inflorescences from 10.59 % (S. virgaurea) to 19.7 % (S. canadensis). The above-ground organs of S. canadensis are characterised by the higher content of catechins (up to 0.19 % in leaves) than S. virgaurea (up to 0.07 % in leaves). Leaves and inflorescences of the studied species of Solidago genus contain no more than 1 % pectins and 10 % protopectins. The concentrations of carotenoids in the leaves and inflorescences of S. canadensis are the same (about 0.1 %), S. virgaurea is characterised by a higher content of this group of compounds in the leaves (up to 0.2 %). The total content of catechins (up to 0.05 %), pectins (up to 2 %), protopectins (up to 7.0 %) and carotenoids (up to 0.01 %) in the leaves and inflorescences of B. perennis exhibit no significant differences. Flavonols are present in smaller amounts in the leaves (no more than 0.6 %), tannins in the inflorescences (no more than 6 %). The total content of phenolic antioxidants in the leaves and inflorescences of S. canadensis, S. virgaurea and B. perennis is within the range of 0.11–0.19 mg/g. The radical binding activity (determined by the DPPH method) of S. virgaurea (1.32–1.61 mg/mL) is two times higher than that of S. canadensis (3.05–3.58 mg/mL) on average. An aqueous-alcoholic extract from the leaves of S. virgaurea inhibits the reproduction of the avian influenza virus A/chicken/Kurgan/05/2005 (H5N1) (neutralization index (NI) is 4.75 lg) and the human influenza virus A/Aichi/2/68 (NI is 4.50 lg).

The problem of neutralising liquid solutions containing hexavalent chromium compounds is considered. The advantages, disadvantages and features of the application of basic methods for neutralising chromium-containing waste, non-traditional approaches and combined technologies are analysed. A readily feasible reagent method is presented for purifying concentrated and dilute solutions from chromium by treatment in two stages: reduction of hexavalent to trivalent chromium using ferrous sulphate or sodium sulphite as reducing reagents, and precipitation of chromium hydroxide. An installation is described in which electrolytes, rinsing and waste water from galvanic production were neutralised. A practical approach to the problem of neutralising the inhibitor solution is proposed, which is similar to the methods used for processing chromium-containing waste from galvanic production. A technological process has been developed for the reagent treatment of an inhibitor with a high concentration of chromates in solution (up to 40 g/L) in one stage by the direct precipitation of poorly soluble chromates. Barium chloride was used as the precipitant. To implement the technology, a schematic diagram of the installation was developed, and appropriate equipment was selected. As a result of processing the inhibitor, waste water, heavy precipitate of barium chromates are formed, which can be used in the future as a raw material, and sludge, which is a non-recyclable waste. Experimental processing of the inhibitor solution shows that the proposed method is effective, economically feasible, readily implementable under industrial conditions, it allows for high purification degree with low consumption of reagents, and reduces the amount of precipitates formed, which confirms the practical significance of the results obtained.

The high-strength nanocomposite cryogels based on polyvinyl alcohol (PVA) and carbon nanotubes (CNTs) have been synthesised and studied. To overcome the problems related to CNTs agglomeration in polar solvents, which limits their uniform distribution over the polymer matrix, cryogel composition was optimised to achieve high strength characteristics. To obtain uniform CNT dispersions, homogenisation in solvents (water, dimethyl sulphoxide (DMSO) and a mixture of DMSO/water = 80 : 20 by volume) in combination with ultrasonic treatment was used. During the experiment, cryogel samples were stretched uniaxially, which allowed us to obtain the ultimate strength values for each sample. Data processing was performed using STATISTICA 10 software. Using regression modelling, the Dependences between the ultimate strength of nanocomposites and synthesis parameters (the concentration of initial PVA solution, its molecular weight, water content in the solvent, and the concentration of CNTs) were established using regression modelling. The obtained regression equation was adequate with respect to Fisher’s criterion, and determination coefficient was R² = 0.81, which confirms the accuracy of the model and its applicability for predicting the strength characteristics of cryogels. In addition to regression analysis, the dependences of the Harrington desirability function on synthesis parameters were analysed. This approach allowed us to identify optimal components ratio for obtaining PVA/CNT nanocomposite cryogels, which significantly increased the efficiency of developing materials with high strength properties. The results of the study emphasise the importance of taking into account various factors when optimising synthesis conditions and also offer new prospects for further research in the area of polymer composites.

The article presents the results of a theoretical analysis and laboratory studies of the zonality of the multidirectional deformation process of heaving of freezing soils using the example of light sandy loam widespread in the seasonal freezing-thawing layer in Russia. Ideas about the characteristic zones of freezing soil are developed, namely, a cryogenic contraction zone is added, the mechanism of its formation is substantiated, and the role in cryogenic heaving of soils is shown. The results are important for the physical formulation of a mathematical model of freezing and heaving of clay soils, taking into account heat and mass transfer and multidirectional deformations, in relation to the fundamentals of geocryological forecasting of the stability of buildings and structures in the area of distribution of frost-susceptible soils in the cold regions of Russia.

Data from detailed and long-term coastal studies in the Arctic have been utilized to estimate the rates of coastal erosion along the Laptev and East Siberian seas, as well as to reveal the specific features of geomorphological and cryogenic coastal processes. Eroding coastlines are dominant in the study region with erosion rates as high as 25 m per year along the coasts composed of very ice-rich permafrost sediments. The Laptev and East Siberian coastline was subdivided into 123 coastal segments each characterized by specific lithology, coastal morphology, and dynamic regime. It was found that the average long-term rates of retreat of the shores of the Laptev and East Siberian Seas are characterized by the highest rates of destruction in comparison with the shores of all other Arctic seas.

The study examines the chemical composition of spring waters in the central part of the Chara basin and its evolution over the past four decades. The current chemical composition of the spring waters is characterized as magnesium-calcium bicarbonate with total dissolved solids (TDS) ranging from 36 to 162 mg/L and fluorine content varying between 0.01 and 4.0 mg/L. This research presents, for the first time, data on the stable oxygen and hydrogen isotopes in the springs of the “Sands” massif. The isotopic composition of these springs is as follows: δ¹⁸O = (-16.95 ± 0.69) ‰, δD = (-130.20 ± 4.42) ‰, d_exc = (5.40 ± 1.38) ‰. The combined results of chemical and isotopic analyses suggest the involvement of glacial waters from the Kodar mountains in the formation of the springs within the massif. These springs are formed through the mixing of waters from aeolian and lacustrine-alluvial deposits with more mineralized intrapermafrost waters of fluvioglacial deposits. The degree of participation of waters from different aquifers is reflected in the fluorine content and isotopic composition of springs. The first aquifer system waters have a heavy isotopic composition and contain less fluorine (0.4-2.0 mg/L). The waters from the second aquifer system have a light isotopic composition and a fluorine content of 2-4 mg/L or more. Over the past 40 years, a decrease in mineralization, the content of Na⁺ + K⁺, Cl^- and F^- in spring waters indirectly indicates an increase in the share of glacial runoff in their nutrition.

The paper presents actual data of methane content measurements in frozen sediments and ground ice in the western sector of the Russian Arctic, at the sites located from the western coast of Yamal to Western Taymyr. The cryolithological structure of sampling sites is presented, and stratigraphic and genetic complexes of sediments and ground ice are identified. It is shown that the methane content in sediments formed during colder climates is generally lower than in warmer periods. Minor differences are noted in the methane content in sediments of different lithological composition. The methane content in wedge ice of different ages remains almost the same. The methane content in massive ice depends on the origin, composition, and freezing conditions of the enclosing sediments and varies greatly from sample to sample, reaching a maximum of 24 mL/kg.

This paper considers a new design of a super-deep pressure seasonally-acting cooling device, the principle of operation of which consists in the pressure mode of refrigerant flow due to the difference in the density of liquid columns in the gas-liquid mixture. A mathematical model of the system functioning has been developed, which allows estimating many parameters of operation, the key ones being temperatures in the evaporator, mass flow rates and velocities of the refrigerant flow in different phases, as well as the depth of the refrigerant boiling in the evaporator. Numerical experiments have been carried out, which have shown that the model adequately reflects the real operating conditions of the system under significant variation of key external conditions, such as ambient temperature and values of specific heat loads on the seasonally-acting cooling device evaporator. The parameters are determined for different depths of the evaporator part. One of the key performance indicators of the super-deep pressure seasonally-acting cooling device was the maximum refrigerant temperature in the evaporator, which turned out to be the most sensitive to changes in the specific heat load and atmospheric temperature. The dynamics of the refrigerant temperature and its distribution along the length of the evaporator determine the ability to maintain the required frozen ground regime.

In the Middle and Late Pleistocene, in the areas of the source and sink of radiative heat in the Northern hemisphere, the effect of dividing the intensity of seasonal irradiation by phases of changes in the intensity of annual irradiation is manifested. The average values of the intensity of summer radiation in the phase of increasing annual exposure exceed those in the phases of decreasing annual exposure. The average values of the intensity of winter radiation in the phases of increasing annual exposure are inferior to those in the phases of decreasing annual exposure. The effect of phase separation manifests itself in different ways in the areas of the source and sink of radiation heat. In the areas of the heat source, the phase separation of the intensity of summer and winter irradiation, on average, in the stages of high-amplitude oscillations of a  400-millennial cycle exceeds the phase separation in the stages of low-amplitude oscillations. In the areas of radiative heat runoff, on average, the phase separation of the intensity of summer and winter irradiation in the stage of low-amplitude oscillations exceeds the phase separation in the stages of high-amplitude oscillations. The values of the phase separation of the intensity of summer irradiation in the stages of high-amplitude and low-amplitude fluctuations in 5-degree latitude zones vary in different directions, and the intensity of winter irradiation is unidirectional. The phase separation is most noticeable in the area of radiative heat runoff of the Northern Hemisphere (the area of the cryolithozone) in the summer half of the year at the stage of low-amplitude oscillations of a  400-millennial cycle. This is typical for the beginning of the Middle Pleistocene (solar epoch 16), the Likhvin interglacial (solar epochs 8 and 9) and the present (solar epoch 1).

Academician of the Russian Academy of Sciences Vladimir Pavlovich Melnikov celebrates his 85th birthday on July 5, 2025. The main milestones of V.P. Melnikov’s scientific biography are considered. His contribution to the creation of a holistic image of the Earth’s cryosphere and the formation of new directions of cryology is analyzed.