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Review and analysis of the modern data on the content of phenol compounds in the plants of the Salix L. genus were carried out. The works aimed at the search for chemotaxonomic markers and their application in systematics are presented. It is demonstrated that the qualitative composition of phenol compounds is an invariable, stable sign for the taxons of the Salix genus. Phenol glycosides may be used to identify morphologically similar species and hybrid forms. Special attention is paid to the species that have been the subjects of investigations in different countries: S . babylonica L., S . alba L., S . raddeana Laksch. еx Nasarow, S . caprea L. and S . acutifolia Willd.

Influence of ionizing radiation on the physicochemical characteristics of poly-N-methylallyl-5-vinyltetrazole (MPVT-A) and the rheological kinetic properties of energy-rich compositions prepared from irradiated MPVT-A samples was studied. It is established that ionizing radiation can significantly reduce the induction time of solidification of the compositions based on MPVT-A.

The literature data on the research in the field of homo- and copolymerization of norbornene and its derivatives are discussed in the review. Due to specific structure, norbornene and its derivatives provide the basis to synthesize the polymers and copolymers with various functionalities, differing from each other in the structure and physical-mechanical characteristics of final products. Depending on polymerization conditions, the polymers synthesized on the basis of norbornene are characterized by high optical purity, high thermal and chemical stability, mechanical strength. Copolymers of norbornene with olefins and acrylic monomers combine the properties typical for norbornenes with such characteristics of polyolefins or polyacrylates as high adhesion, elasticity, flexibility of macromolecules, which promotes broadening of their application range. Thus, the availability of the raw material basis of norbornene and its derivatives, together with the unique performance characteristics of the polymers and copolymers based on them, attracts the attention of researches to the studies into the synthesis of new norbornene monomers and the synthesis of polymers and copolymers on their basis for use in various branches of industry. The data presented in the review provide evidence of the promising character of studies in the area of the synthesis of high-molecular compounds with valuable performance characteristics on the basis of norbornene hydrocarbons.

Regulation of the transport characteristics of oil is often implemented with the help of depressor and inhibiting additives. A characteristic feature of new developments in the area of oil additives is the composite nature (two or more components of the active substance), which provides their multifunctional action. Results obtained in the investigation of the effect of complex additives based on polyalkylacrylate (PAA) and petroleum-polymer resins modified through nitration (N-PPR) on the chilling temperature and viscosity of paraffin and high-paraffin oils of West Siberia, as well as on the amount and composition of asphaltic resinous paraffin sediments (ARPS) are presented. It is established that, in comparison with the additive based on PAA, the complex additive causes a decrease in the amount of ARPS (by 10 % as average), a two-fold increase in the depression of oil chilling temperature and a decrease in its dynamic viscosity. The efficiency of the complex additive was revealed to depend on the method of N-PPR preparation. The best results with respect to all parameters are demonstrated by the additives for which the N-PPR were synthesized by means of ion and initiated polymerization. It was shown in the evaluation of the surface activity of resinous asphaltene oil components and the components of the developed compositions that among the studied samples N-PPR are characterized by the lowest surface tension. The resins of oil kinds under investigation differ from each other in surface tension only insignificantly. Among all components, asphaltenes are characterized by the highest surface tension. A new complex additive based on PAA and modified PPR is proposed, which may be used to reduce the chilling temperature and viscosity of paraffin and high-paraffin oil, as well as the amount of ARPS formed in them.

The quantitative content of 22 chemical elements (As, Br, Co, Cr, Cu, Mn, Mo, Nb, Ni, Pb, Rb, Sc, Se, Sr, Ti, Zn, Zr, V, Y, Ca, Fe, K) in the vegetative organs of Hemerocallis hybrida was determined for the first time with the help of X-ray fluorescence analysis with synchrotron radiation (XRD). Comparative data on the elemental composition of leaves and rhizomes in the plants of varieties Speak to me and Regal Air in the forest-steppe zone of West Siberia are presented. The specific features of the content of 19 microelements and 3 macroelements in above-ground and underground organs were revealed. The concentrations of all elements in the leaves and rhizomes of Speak to me and Regal Air plants were at the maximum permissible level. The leaves of Regal Air were distinguished by the higher (by a factor of 1.5-7) content of molybdenum, bromine, chromium, rubidium, selenium. The concentrations of lead, strontium, yttrium, zirconium, niobium were 1.5-6 times higher in the leaves of Speak to me. Underground organs were found to be the richest in trace elements. It was shown that the total content of trace elements is 1.5-3 times higher in the organs of the Regal Air variety. The variety specificity of the quantitative content of chemical elements in vegetative organs is detected.

The necessity to introduce the principles of green economics into subsoil management as one of the most important branches of Russian economy affecting the quality of the environment to the highest extent is considered. The main kinds of the effect of mining and primary processing of mineral resources on the state of geological environment, surface relief and soil cover are presented, as well as the forms of the influence on human health for different stages of the industrial process. The long-term negative effect of the consequences of mineral resource mining is stressed, together with the high cost of recultivation and rehabilitation works. The major goals in the introduction of green approaches in subsoil resource management include improvement of the normative-legal basis of subsoil usage with respect to the ecological aspects of raw material mining and processing, the formation of the state authorities for geological management and innovative development of the economics of the country, broadening of the range of application of financial mechanisms for the technological renewal, public disclosure of the entire ecologically significant information on the companies involved in subsoil resource management.

Laser ignition (λ = 1064 nm, τ_i = 120 ms) of the coal samples of different marks from the Kuznetsk coal basin was studied. Three consecutive stages of ignition were detected for all marks of coal. These stages are characterized by the threshold radiation energy densities H_cr⁽¹⁾, H_cr⁽²⁾, H_cr⁽³⁾ which are characteristic for each coal marks. It was established that the first stage involves surface heating and ignition of micro protrusions on coal particles. The duration of this stage does not exceed the time of the laser pulse. At the second stage, volatile matter are observed to evolve and ignite. The duration of combustion depends on the density of radiation energy. Ignition of the nonvolatile residue occurs at the third stage, upon reaching H_cr⁽³⁾; burning time is 40-150 ms. It was demonstrated that the threshold value at the first stage varies only slightly for all coal marks. For bituminous coal, the second threshold decreases with an increase in coalification degree, while the third threshold increases. The second and the third thresholds for lignite are comparable with the values of H_cr⁽²⁾ and H_cr⁽³⁾ for low metamorphic bituminous coals. Experimental results allow us to conclude that ignition occurs at the first and the third stages according to the heterogeneous mechanism, while at the second stage it occurs according to a homogeneous mechanism.

Thermal reactions proceeding through hydrogen transfer from the polyaromatic compounds of coal tar pitch to model organic compounds (nitrobenzene, chlorophenols, and chloraniline) are investigated. Within the temperature range 270-360 ^оC, there is a complete conversion of nitrobenzene into aniline (with a yield of 75-82 %) and condensation products remaining in the pitch. It was found that 4-chlorophenol enters hydrodechlorination starting at a temperature of 300 ^оC and leading to the formation of phenol and condensation products. The reactivity of 2,4-dichlorophenol and 2,4,6-trichlorophenol is higher than that of 4-chlorophenol. The features of the reactions are compared using coal tar pitch and hydroaromatic compounds as hydrogen donors.

The oxidation of biofuel samples with different lignin content (10, 20 and 70 %) was studied. The kinetic parameters of combustion reactions were obtained which allowed us to consider the process as a two-stage one. The sample with 20 % lignin content was shown to have a high reactivity in oxidation reactions.

The properties of the pitch samples obtained through the thermal dissolution of coal were studied using a unit with a flow tubular reactor. Their main differences were analyzed in comparison with coal-tar pitch. It was shown that in terms of elemental composition, extractive pitches are characterized by lower carbon content and a high percentage of oxygen, compared to the traditional binder. Their technological parameters are characterized by increased softening point and low coke residue. These features are a consequence of molecular composition. According to IR and NMR spectroscopy, the aromaticity factor of the alternative binder is relatively low, the organic matter contains a large number of aliphatic groups (-CH₂- and -CH₃), as well as polar oxygen-containing groups such as carbonyl, ether, etc. The latter groups have a negative effect on the rheological properties of extractive pitch. The influence of coal type and coal-oil paste composition on the yield and quality indicators of the pitch-like products of thermal dissolution was analyzed. The use of a coal-solvent mixture with the high percentage of coal is not reasonable because of the high viscosity of final extractive pitches, which hinders the preparation of a homogeneous mixture for the formation of carbon-graphite products.