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The results of the application of a new methodology for testing the hypothesis of the independence of random variables in the analysis of remote sensing data of anthropogenic territories are presented. The basis of the technique is a nonparametric pattern recognition algorithm corresponding to the maximum likelihood criterion. Linear and nonlinear dependences between the spectral features that characterize anthropogenic territories are determined. The results of the assessment of anthropogenic territories based on spectral remote sensing data are considered.

An algorithm for single pulse chirp signal detection at low signal/noise ratios is proposed. The proposed detection algorithm is based on the cross-correlation of the input chirp pulse and its copy subjected to a frequency shift. As a result of the proposed transformation, a gain in the signal/noise ratio is achieved, which allows the effective use of threshold detection.

The use of thermal imaging for reconstructing historical heritage sites is limited by the influence of modern plowing and the absence of archaeological sites with contrasting thermal properties. A distinctive feature of the proposed statistical analysis algorithm is the use of Haralick texture features at the stage of feature extraction. Subsequent segmentation of the image makes it possible to identify sections of the occupation layer of various capacities as areal landscape objects. The interpretation of their properties is based on the reference data of interdisciplinary research - excavations, geophysics, and soil drilling. An assessment of the trends in the relative locations of segments of different classes and the ratio of their areas allows us to put forward a hypothesis about the boundaries of an archaeological site. At the site of the medieval Kushmanskoe III settlement (Udmurtia), the analysis of the structure of the segmented thermal image reveals fundamental differences in the distribution of the humus layer in the settlement and the adjacent territory, which was not subjected to anthropogenic influence. The proposed algorithm can be considered as an effective tool for studying historical heritage sites.

The results of testing the effectiveness of using two measurement procedures: self-calibration and auto-compensation are presented. These procedures are used in laser image generators with circular scanning simultaneously to reduce the error in the synthesis structures. It is revealed that, in using such a strategy, it becomes advisable to limit the complexity of the hardware implementation of the self-calibration procedure due to the action of disregarded sources of distortion. To reduce this objectively occurring limit, it is proposed to use an optical-mechanical system configuration in these image generators, similar to what actually occurs when calibrating their angular sensors, as well as continuously monitor and take into account the manifestations of distorting factors whose contributions are unstable over time.

Developing the approach to the synthesis of polyfluorinated boron derivatives formulated as one precursor, a series of target products, tested previously using O-, N-, and C-nucleophiles, a series of potassium 4-arylthiotetrafluorophenyltrifluoroborates was obtained through the action of organylthiols in the presence of bases on potassium pentafluorophenyltrifluoroborate.

In the studies of the human habitat, similar organic substances are commonly determined summarily (group analysis). In the present work, a review of publications related to the years 2015-2023, dealing with the group analysis of hydrochemical objects and foodstuffs is presented. In both cases, a traditional and most widespread method of group analysis is the total index calculation, in spite of the metrological incorrectness of this method. The corresponding assays include measuring of generalized signals, construction of univariate calibration and rough estimation of the total content (c_Σ) of the analytes, calculated for a certain standard substance. The new group analysis instruments for hydrochemical objects are the inverted multivariate calibrations, and for antioxidant determination in foodstuffs - the interval estimates of c_Σ. These new group analysis variants lead to more correct results, however, they have not been studied in sufficient detail and are rarely used in actual practice. The application of multivariate calibrations is hindered by the labour-intensive construction of training sets, while the use of interval estimates is hindered by the intergroup signal selectivity, leading to excessively wide intervals. The trends in the development of group analysis and promising directions of future investigations are discussed.

The influence of polyisobutylene of grades P-30 and P-200 on the rheometric, physico-mechanical and dynamic properties of rubber used for manufacturing the products exposed to sea water has been investigated. The rubber compound included: butadiene-styrene DSSK-628V and chlorobutyl KhBK-139 rubbers, vulcanising agent (sulphur), vulcanisation accelerators (2,2'-dibenzthiazole disulphide, guanide F), vulcanisation activators (zinc white, stearic acid), antioxidant (N-phenyl-2-naphthylamine), softeners (rosin, petroleum bitumen, factis), fillers (trans-polynorbornene, carbons black (P 514, P 803), and natural chalk). As a result of the studies, it is established that with an increase in the content of polyisobutylenes from 5 to 20 phr a change in the physico-mechanical properties of rubber is observed (a decrease in tensile strength, hardness, and tear resistance), while the relative elongation at break and the dynamic properties of rubber increase. Moreover, with polyisobutylene content up to 15 phr, the physico-mechanical properties of rubber change within acceptable limits, but at 20 phr these properties deteriorate sharply. Vulcanisates containing polyisobutylenes P-30 and P-200 up to 15 phr exhibit smaller changes in physico-mechanical properties and mass after exposure to sea water. It has been determined that rubber containing 15 phr polyisobutylene P-200, due to its physico-mechanical, performance and dynamic properties, can be recommended for the manufacturing the products operating under exposure to sea water.

The influence of the structure of low molecular weight nitrogenous bases in heavy oil on the composition and aggregative stability of asphaltenes has been studied. The objects of investigation were asphaltenes of heavy oil from the Usinsk field, as well as asphaltenes of model petroleum systems with nitrogen content 1.0-3.0 wt%, obtained by mixing the original oil with quinoline and pyridine. IR spectroscopy and elemental analysis were used to determine the composition and structure of asphaltenes. The colloidal stability of asphaltenes was analysed by spectrophotometry. It is shown that the introduction of nitrogenous bases into heavy oil leads to a decrease in hydrogen content with an increase in the proportion of nitrogen, which points to the incorporation of pyridine and quinoline molecules into the supramolecular structure of asphaltenes. The main reason for the incorporation of nitrogenous bases into asphaltene aggregates is the p-stacking interactions of aromatic rings. The colloidal stability of asphaltenes, assessed as the time of sedimentation onset, is determined to increase by a factor of 1.5, with an increase in pyridine content, and the degree of sedimentation inhibition can reach 90 % with respect to asphaltenes in the original oil. On the contrary, the presence of quinoline in asphaltenes causes a several-fold decrease in the time of their aggregation onset, but it also promotes detention of a part of aggregates in the colloid state, which results in a decrease in the amount of precipitate in comparison with original oil.

The features of the behaviour of rare earth elements (REE) and strontium in hemihydrate and dihydrate processes of sulphuric acid processing of Khibiny apatite concentrate have been studied on the basis of investigation of the residues of aqueous leaching of phosphogypsum obtained under production conditions. It has been shown that the increased degree of REE ingress into phosphogypsum of the hemihydrate process, compared to phosphogypsum of the dihydrate process, is determined by the technological features of these processes: higher temperature and REE concentration in the liquid phase of the pulp of the hemihydrate process, compared to the liquid phase of the pulp of the dihydrate process. In contrast to existing ideas, it is theoretically justified and experimentally confirmed that a significant part of REE in phosphogypsum of the hemihydrate process is present in the form of rhabdophane. Rhabdophane was not found in phosphogypsum from the dihydrate process, and it is most likely that REE in phosphogypsum from the dihydrate process are isomorphically cocrystallised with gypsum. It has been established that strontium occurs partially in the form of celestine in phosphogypsum of both processes. It is shown for the first time that celestine, present in phosphogypsum of the dihydrate process, contains isomorphically cocrystallised REE. It has been suggested that isomorphically cocrystallised REE may be also present in celestine from phosphogypsum of the hemihydrate process. The influence of REE forms present in phosphogypsum on the possibility of its sulphuric acid leaching is discussed. The results obtained in the work are of high practical importance because sulphuric acid leaching is widely recommended for organising the industrial extraction of REE from phosphogypsum obtained during sulphuric acid processing of the Khibiny apatite concentrate.

The results of studies conducted at the Institute of Combustion Problems (Almaty, Kazakhstan) on the synthesis of nanocarbon materials and their application for environmental purposes are presented. The procedures have been developed for obtaining nanocarbon materials from rice husk and walnut shells (graphenes and activated carbon, respectively), the physicochemical properties of the synthesised materials and the possibility of their practical use are studied. Graphene investigation by infrared and Raman spectroscopy allowed us to analyse the surface functional groups and the structural features of the material composed of a mixture of amorphous carbon and graphene, the ratio between these components depending on synthesis method. With an increase in the amount of the alkaline agent, the content of graphene component in the structure of carbon material increases. The porous structure and morphology of carbonised materials from rice husk and walnut shells were characterised according to the data of scanning electron microscopy. Nanocarbon graphene structures and activated carbon synthesised from the waste plant materials have demonstrated good adsorption properties for sea water desalination and sorption of toxic gases.