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This article addresses the problem of line identification in high-resolution vibrational-rotational spectra. We suggest an approach based on heuristic search applied in artificial intelligence systems for automatically identifying a set of molecular energy levels observed in a spectrum. Such systems solve the problem of finding a sequence of operations for transforming input data (formulas, knowledge) that brings the data to a certain target or desired state. The proposed approach simultaneously analyzes several rotational sublevels in a spectrum, thus enabling more reliable identification of the corresponding spectral lines using more information. The results can be used in optical atmospheric measurements and molecular physics.

Asphaltenes as self-organizing supramolecular structures are of great scientific and practical interest. An urgent problem is to reveal the regularities of the directed formation of planar associates of asphaltenes and condensed graphite-like structures. For the purpose of investigating the self-organization of the molecular aggregates of coal-tar pitch asphaltenes, the morphology and structure of the particles of asphaltene powder obtained from coal-tar pitch asphaltenes by method of selectively soluble groups was studied by complex of physicochemical methods. It was shown that the crystal structure of asphaltene powder particles is represented mainly by turbostratic carbon structures. According to XRD data, the coke residue after the thermolysis of asphaltenes is characterized by the presence of crystallites consisting of naphthenoaromatic layers.

The biological activity of humic acids produced from the coals of the Kansk-Achinsk and South Ural basins was evaluated by means of phyto-testing in a series of laboratory and field tests. A connection between the structural group parameters of the organic acids of humic preparations (humic acids) and their biological activity was revealed in the series of field experiments at the sites characteristic of the most widespread technogenic landscapes of Siberia. It was established that in the case when humates are applied at the burrows of open-pit coal mines with the lack of moisture, it is necessary to take into account the hydrophobic-hydrophilic parameters of the preparations. Preparations with the high degree of aromaticity of humic acids are more efficient for the-reclamation of the burrows of brown coal deposits.

Bitumen extraction is a promising project of brown coal processing. It raises the task of identifying and quantifying the components of recoverable bitumen. In this paper, the method of gas chromatography-mass spectrometry is used to solve this problem. The composition of high-molecular fatty acids of brown coal bitumen from the Tyulgan deposit was studied taking into account the patterns of molecular ion fragmentation for the butyl esters of fatty carboxylic acids under ionization by electron impact. The ethanol extract fraction was investigated. The NIST-11 Database and ChemStation D.01.02. software was used to identify the butyl esters of fatty carboxylic acids.

Thermogravimetric investigation of five brown coal samples from various deposits in Russia and Mongolia was carried out in the inert and oxidizing media. A comparative analysis of the data obtained allowed us to reveal that brown coal of the Kangalasskoe deposit has higher thermal stability. This is confirmed by a higher yield of solid residue from pyrolysis in the inert atmosphere, lower yield of volatile substances, and the shift of the maximum of thermochemical decomposition of coal substance to higher temperatures. Temperature limits (ignition temperature for particles and the final temperature at which the coke residue burns out) of thermal degradation of the organic mass of the studied brown coals in the oxidizing medium were determined. It was demonstrated that brown coal samples were characterized by increased reactivity with respect to oxygen. It was established that the ignition temperature increases with an increase in the carbon content (С^daf) in the samples and a decrease in the yield of volatiles (V^daf), while the final temperature of the oxidation process significantly correlates with the aromaticity index f _a of the organic mass of coal.

Thermal decomposition of brown coal from the Baganuur deposit in Mongolia and gas coal from the Ulug-Khem deposit in Tuva was studied using thermogravimetry (TG) and differential thermogravimetry (DTG). The stage-by-stage thermal decomposition was revealed under the conditions of programmed heating to 900 °C with different rates in the argon atmosphere. Using the model-free and isoconversion methods of Ozawa-Flynn-Wall (OFW) and Kissinger-Akahira-Sunos (KAS), the dependence of the activation energy on the degree of coal decomposition was established, and the kinetic parameters of pyrolysis were determined. Within the range of coal conversion degrees from 0.1 to 0.9, the average values of pyrolysis activation energies for brown coal and gas coal were 186 and 239 kJ/mol (OFW method), 182 and 238 kJ/mol (KAS method), respectively. The kinetic compensation effect during coal pyrolysis was observed. This may be due to the multicomponent and multifunctional composition of coals.

The group and component composition of n-heptane and alcohol-benzene extracts of bitumen obtained from the brown coal of the Tyulgan deposit were investigated. Application of ¹³С NMR spectroscopy (CPMAS) and IR Fourier spectroscopy, gas chromatography-mass spectrometry, liquid chromatography allowed us to determine that n-heptane and alcohol-benzene extracts are represented by similar groups of substances: alcohols, phenols, alkanes, small amounts of carboxylic acids and aromatic compounds, esters, unsaturated hydrocarbons. The substances of these groups are distributed in these extracts to different extents, with the prevalence of compounds of aliphatic nature. A number of biologically active susbtances were identified in the extracts: tetra-, hexa-, octadecanouc acids, butylparabene, ferruginol, eicosane.

The dissolution of trinitrotoluene (TNT) in a low-melting nitramine, diethanolnitramine dinitrate (DINA), was studied, and a phase diagram for the TNT/DINA system was built. The enthalpy of TNT dissolution in DINA within the temperature range 55-75 °С was measured. The yields of condensed carbon (CC), detonation nanodiamonds (DNDs) and DND content in CC versus the composition of TNT/DINA cast melts upon detonation in a blasting chamber were experimentally studied. The yield of CC was found to linearly decline with decreasing TNT content in the composition, with the content of the diamond phase in CC going through the maximum. The highest yield of DNDs was achieved when the TNT content in the mixture was close to the eutectic (~40 %).

Fluorination of lanthanum oxide with ammonium fluoride is studied. Among all the known rare earth elements, lanthanum oxide is most commonly used as a stabilizing catalyst component, in particular in the hydrogenation of heteroatomic compounds of biofuel. Previous thermodynamic and thermogravimetric studies point to the multistage fluorination of La₂O₃ with ammonium fluoride. The reaction kinetics is correctly described by the kinetic equation of a contracting sphere with the activation energy equal to 33.65 kJ/mol. The X-ray phase analysis of the formed crystal phase showed that complex fluorides like (NH₄)₃La₂F₉∙H₂O and (NH₄)₃LaF₆∙0.5H₂O are formed as impurities during the interaction of La₂O₃ with NH₄F in addition to the major product (LaF₃).

The effect of various methods of physical action on the processes of extraction and organic synthesis is considered. The results of the authors’ works are summarized, and it is demonstrated that the methods of mechanochemical, ultrasonic and microwave activation provide an increase in the yield of target products, a decrease in the volume of solvents used, in time and energy consumption, compared to traditional processes.