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Results of the field studies of mercury emission from the cyanation waste dump in the oxidation zone of the Novo-Ursk pyrite polymetallic deposit (Ursk settlement, the Kemerovo Region) are presented. Mercury content in the surface atmospheric layer above the dump surface is determined to vary within the range of 20-3600 ng/m³, while the diurnal average maximum permissible concentration (MPC_d) is 300 ng/m³, thus this value is exceeded in some sites by a factor of 12. The regional background above the dump surface is exceeded by a factor of 570 on average. Comparison between the morning and evening measurement results shows that mercury concentration increases in the evening. This is due to the active emission of mercury under the action of solar radiation and heating of the dump surface. Numerical models of mercury propagation are constructed using the methods of mathematical modelling. According to the model built up on the basis of the maximal measured concentrations, the whole territory of Ursk settlement is within the zone of very high mercury vapour concentrations. Calculation over the averaged concentrations shows that the safe level is achieved at a distance of 600 m from the dump, but within the boundaries of the settlement. The obtained results provide evidence of the danger of mercury action on the population of the settlement and pose the goal of more detailed investigation of air composition over old gold mining waste storage facilities.

Currently there is no agreement among the researchers worldwide about the mechanism of MFI-type zeolites deactivation due to coke accumulation in the areas of coke localization. This problem does not allow answering the question about the stability of these zeolites and their resistance to the reversible deactivation by coke. Our research provides the solution to this problem using physical and chemical methods: the electron paramagnetic resonance, X-ray photoelectron spectroscopy, thermal analysis and catalytic method of methanol conversion into hydrocarbons. We show that the key mechanism of coke formation is carbenium mechanism. Deactivation of zeolites occurs mainly due to the coke accumulation on the external surface of crystals of MFI-type zeolites. The contribution of “hydrocarbon pool” mechanism is negligibly small compared to the contribution of the carbenium mechanism of olefin formation by the dehydration reaction. This understanding allows increasing the stability of MFI type zeolites to coke formation by removing the acidic centres from the external surface of the crystals.

The effect of high-temperature treatment (900 ^oC) of N339 carbon black in the presence of carbon dioxide, followed by low-temperature treatment (-5 ^oC) in a mixture of oxygen with ozone, on its properties was studied. As a result of complex oxidative action, a carbon material is formed with textural properties that are several times higher than the levels of values characteristic of the original carbon black. The oxygen content in the final material can vary from 19 to 35 wt. %, which suggests that it is promising for use as a high-performance pigment.

The conditions for the formation of Pickering emulsions in the crude oil-water system were studied using cellulose nanocrystals with partially acylated surface as a stabilizer. Biodegradation of the obtained emulsions by natural microorganisms was investigated depending on the ratio of components in the emulsion. The formation of stable emulsions was evaluated depending on the nanocellulose concentration. At a low content of cellulose nanocrystals, the stability of the emulsion is achieved only with an increase in the concentration of the background electrolyte. Oil dispersing in water allows conserving the contact between the air and water phases, which promotes efficient biodegradation of oil due to an increase in the area of contact between oil microdrops and water. According to chromatographic analysis, the residual content of hydrocarbons in the emulsion is 20-25 % after incubation with an inoculant of microorganisms for 30 days. This method enhances the stability of oil dispersion, which promotes an increase in the rate of its biodegradation on various water surfaces.

The bioecological features of Myosotis pseudovariabilis Popov from the section Sylvaticae (Popov ex Riedl) Tzvelev, an endemic of the lover reaches of the Yenisei river (Krasnoyarsk Territory) are considered. Taxonomy, geographical distribution, species protection, and morphological characters of vegetative and generative organs are discussed. Original researches on element composition of green mass of leaves of M. pseudovariabilis in connection with soil composition and ecological conditions of species existence are carried out. Phenological characteristics of the species as well as plant response to abnormal weather conditions were studied for the first time. It has been noted that small populations of M. pseudovariabilis, Heracleum dissectum Ledeb. are confined to shrub thickets in river and stream valleys, while large populations are characteristic of meadows of natural and anthropogenic origin. The conjugate development of cenoses with participation of M. pseudovariabilis and Cirsium helenioides (L.) Hill was revealed. Plant communities M. pseudovariabilis is an explerant; its life strategy is aimed at the formation of long creeping epigeogenic rhizomes that radially take up space due to vegetative rosellate shoots, which have buds of regeneration on the ground surface and are covered by dry leaf debris. At present, due to the reduction of human activity, former hayfields, arable lands and vegetable gardens are overgrown with shrubs and tall grasses, which contributes to creation of favorable conditions for growth of M. pseudovariabilis and increase of its populations, since the main ecological niche of the species is meadow shrub communities of the eutrophic successional vegetation series.

The article presents the results of morphological studies of anthers, as well as live and dehydrated pollen grains of 9 species of the genus Tulipa L. from 4 sections. In the living state, the grains are spherical or elongated-ellipsoidal in shape, ranging in size from 40 to 78 mm. For a spherical shape, the type of aperture is characteristic - a pore, and for an ellipsoid - a colpi. Based on the determination of the place of germination of the pollen tube, which is located only on the distal side and is pore in the species of the sections Leiostemones, Spiranthera, Orithia and a furrow in the species of the section Eriostemnes, it was found that the pollen in the studied species is distal-1-aperture. Aperture without operculum (Leiostemones) or with it (Spiranthera, Eriostemnes, Orithia). The palynomorphological features correspond to the sections of the genus according to the classification of A.I. Vvedensky with additions by Z.P. Bochantseva. The data obtained do not confirm the expediency of including the section Spiranthera.

The species Cetraria crispiformis is very poorly studied in Russia. Only 6 points are indicated on the map of the range of the species for the territory of Russia. The purpose of this study was to revise herbarium materials in order to detect new localities of the lichen, as well as to map the range of the species in Russia. The purpose of this study was to revise herbarium materials in order to detect new localities of the lichen, as well as to map the range of the species on the territory of Russia. The material for the study was herbarium collections, including type materials kept in the Lichenological Herbarium of the Komarov Botanical Institute of the Russian Academy of Sciences (LE), as well as single specimens kept in the Herbarium of the Karelian Scientific Center of the Russian Academy of Sciences (PTZ) and the M.G. Popov Herbarium of the Central Siberian Botanical Garden of the Siberian Branch of the Russian Academy of Sciences (NSK). The study was carried out by a comparative morphological method. The distribution map of the species on the territory of Russia was compiled using the point mapping method. As a result of the revision of the herbarium materials of C. islandica s.l. about 40 (30 new) localities of the species C. crispiformis have been identified. A distribution map of this arctic-northamphiatlantic lichen on the territory of Russia has been compiled, showing that the species is found here almost exclusively along the coasts of the northern seas (Barents, White, Kara) and on the Arctic islands. Outside the coasts (in more continental regions), the species is practically not found, and if it occurs, then in special conditions - in sphagnum bogs. The most remote localities of the species from the coasts are in the Komi Republic on the Timan Ridge and in the Pskov Region on the “Eastern Bog Massif”. As a result of the study of type specimens of intraspecific taxa of C. islandica described by K.A. Rassadina, it was found that the type C. islandica var. polaris f. grumulosa Rass. (LE L127), the name of which was considered by Kärnefelt (1979) as a synonym of C. islandica subsp. crispiformis does not belong to the species C. crispiformis, but represents one of the forms of C. islandica s.l. Synonyms and their type specimens are given.

According to the results of the expedition routes in 2021-2022, data on the findings of new and rare adventive plant species in the Southern Urals (Republic of Bashkortostan and Orenburg Region) are presented. For the first time for the Southern Urals are given: Carthamus tinctorius, Glycine max and Heliopsis helianthoides. For the Republic of Bashkortostan, the following species are given for the first time: Cotoneaster lucidus, Grindelia squarrosa; for the Orenburg Region: Dracocephalum nutans, Gaillardia aristata, Portulaca grandiflora, Solidago gigantea, Sorghum sudanense, Thladiantha dubia. New localities of 3 rarely occurring adventive plant species (Amaranthus hypochondriacus, Senecio dubitabilis, Setaria italica) in Orenburg Region are given.

Galium zaisanicum Pinzhenina et Kupr. is described as a new species from East Kazakhstan from section Galium. G. zaisanicum grows in Zaisan depression on Kiin-Kerish clays. The material was collected in the East Kazakhstan region of the Republic of Kazakhstan in the intermountain depression, on the clays of Kiin-Kerish. G. zaisanicum shows an external morphological similarity with species G. ruthenicum Willd., G. saurense Litv., but differs by tomentose of stem, length of internodes, shape and pubescence of leaves, shape of corolla lobes, pubescence of corolla, shape of anthers, and sculpture of fruit surface. Data on the surface sculpture of the mericarpies confirm the close relationship of the species G. zaisanicum, G. ruthenicum and G. saurense Litv. G. zaisanicum grows in fine-grained areas with an admixture of quartz sand and kaolin clay scour products in semi-desert communities involving members of the families Poaceae, Amaranthaceae, Asteraceae. For the new species, the holotype, isotypes and paratypes are given. Detailed description, discribution, ecologi, illustrationsas as well as a comparison with morphologically similar species are provided.