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The annual cycles of the Northwestern Siberian warblers are analyzed in order to identify the features that determine the possibilities of further development of the Subarctic in the conditions of current climate change. The penetration of Philloscopus inornatus, Ph. trochiloides and Silvia curruca into the Subarctic is limited by woody vegetation, Ph. borealis - by high willows of the river valleys of the Middle Yamal. Ph. trochilus, Ph. collybita and Acrocephalus schoenobaenus inhabit the strip of subarctic tundra of Yamal. The last three species are moving in a northerly direction. The probable advance of forest-tundra-tundra landscapes to the north under conditions of further warming will entail the northward movement of forest and shrub birds, not only warblers, since there are no factors preventing this.

In this work reconstruction of past vegetation and fire dynamics in north Altai was performed by pollen and charcoal investigation of peat deposits of Maly Labysh Mire located in the upper reaches of the Kondoma River in Gornaya Shoriya National Park (52.6306° N, 88.0829°^{E, 490 м a. s. l.). Lithology and radiocarbon dating has shown that the swamp is of lacustrine origin. The lake originated about 3000 years ago, and about 2200 years ago it turned into a swamp. Spore-pollen analysis of lacustrine and peat deposits revealed repeated changes in the vegetation cover, probably caused by climate instability during the last 3000 years. In general, 2 humid millennial periods (3000-1800 cal. yr. BP and 550-200 cal. yr. BP) were identified when the role of fir ( Abies sibirica ) increased in the forests, alternating with 2 drier periods (1600-900 cal. yr. BP and 200 cal. yr. BP - contemporary) when the fir gave way to birch ( Betula pendula and Betula alba ) forests. The article represents also data on the dynamics of paleo fires in the area of the Maly Labysh Mire based on micro- and macrocharcoal analyzes. It was found, that in peat deposits of Maly Labysh Mire the maxima of micro-charcoals record wetter periods, but macro-charcoals - drier periods, while periodical flooding of the bog with river waters took place. With transition of mire from the flooding regime to unflooding regime, the microcoals and macrocoals began to synchronously reflect drier periods. The results of the study showed that the frequency and intensity of fires in Gornaya Shoriya in the last two thousand years correlate well with previously identified periods of lowering of the groundwater level in the mire [Kuryina, Blyakharchuk, 2020] and with a decrease in the amount of atmospheric precipitation in the Holocene [Arkhipov, Volkova, 1994]. A conclusion is drawn about connection of paleo fires with dynamics of humidity of climate, which in complex influenced on vegetation change in Gornaya Shoriya.}

In this work, a dendroecological study of the parameters of annual rings of Scots pine ( Pinus sylvestris L.) trees in the forest-steppe and steppe zones of Eastern Transbaikalia was carried out. For the first time, two new tree-ring chronologies (Nov and Tz) were built for the study area. They were constructed using digital growth ring anatomy methods and include four parameters: tree ring width, early wood width, late wood width, and late wood optical density. The analysis of the obtained chronologies made it possible to estimate the parameters of tree growth in the conditions of the forest-steppe (Nov) and steppe (Tz) zones and to reveal the presence of a reliable connection between them. Calculation of sliding correlation coefficients revealed periods of falling correlation coefficients below reliable values. This indicates the impossibility of constructing a generalized regional chronology for the forest-steppe and steppe zones of Eastern Transbaikalia. Comparison of the obtained chronologies with meteorological parameters (surface air temperature and atmospheric precipitation), with the calculated indices of aridity and moisture (Selyaninov’s hydrothermal coefficient, Pedya’s aridity index, Palmer drought severity index) showed the most sensitive characteristics of the annual ring in the study area. In the forest-steppe zone, the highest values of the correlation coefficients were obtained between the average annual precipitation and the annual ring width ( r = 0.59), early wood width ( r = 0.59), and also between the average air temperature for a hydrological year and the late wood width ( r = 0.51). For trees of the steppe zone, the largest significant correlation coefficients were obtained between water year precipitation and the annual ring width ( r = 0.43), early wood width ( r = 0.43), as well as between the Palmer drought severity index for June-September and the width of early wood ( r = 0.52).

This review considers the history of the development and implementation of the method of gibbsite thermal activation in Russia, the physicochemical foundations of the method, and the outlooks for its use for the preparation of supports and catalysts based on aluminium oxide. The contribution of R. A. Buyanov and his collaborators to the development of scientific foundations and the practical application of the thermal activation method is considered.

The studies carried out by us during the recent years aimed at the use of three new families of porous metal-organic frameworks NIIC-10, NIIC-20 and NIIC-30 (NIIC - Nikolaev Institute of Inorganic Chemistry) for the separation of industrially significant mixtures of hydrocarbons, in particular ethane and ethylene, benzene and cyclohexane, as well as the isomers of xylene, are evaluated.

A technology for producing hydrogen and carbon nanotubes from natural gas has been developed. The design of a pilot installation was developed and tested in the decomposition of natural gas using a series of CoO-MoO₃-Fe₂O₃-Al₂O₃ catalysts_. The optimal catalyst composition 30 % CoO-7 % MoO₃-25 % Fe₂O₃-Al₂O₃ was identified. This catalyst makes it possible to obtain 30 L of hydrogen and 12 g of carbon nanotubes from natural gas with 1 g of the catalyst at moderate temperatures (700-750 °C). It was demonstrated that the installation for natural gas processing could operate in a continuous mode with an additional catalyst supply. The concentration of hydrogen in the methane-hydrogen mixture at the reactor outlet reaches 80 vol. %.

The literature data and experimental results of the authors on the state of bismuth in the solutions of chloric and nitric acids, as well as on the synthesis of various bismuth compounds with the participation of polynuclear complexes, are systematized and summarized. It is shown that hydrolytic processing of bismuth-containing nitric solutions through bismuth precipitation at the process temperature of 65±5 °C and рН 0.7-1.0 in the form of compound [Bi6O4(OH)4](NO3)6 • H2O, followed by its transformation by means of washing with water into the compound [Bi6O5(OH)3](NO3)5 • 3H2O allows efficient separation of bismuth from impurity metals, which leads to a high-purity product with lead, silver and copper content less than 1 • 10-5 %. It is established that these compounds may be used as precursors to obtain high-purity compounds: basic bismuth carbonate, gallate, succinate, as well as medium bismuth nitrate, citrate, ditartrate trihydrate. It is stated that the complex [Bi6O4(OH)4]6+ is the initial cationic form for hydrolytic precipitation of bismuth from solutions; only the ratio of bridging oxo and hydroxo groups changes during hydrolysis, with the conservation of the Bi6O82+ core, which serves as the central structural unit. It is shown that the addition of sodium tribromophenolate to the bismuth-containing nitric solution results in the formation of bismuth oxohydroxotribromophenolate [Bi6O6(OH)2](C6H2Br3O)4. It is determined that bismuth precipitates from chloric and nitric solutions after the addition of even oxohydroxocarboxylates in the form of the compounds with the composition Bi6O4(OH)4(СnH2n + 1COOO)6 (n = 2-22), where (СnH2n + 1COOO)- is the carboxylic acid anion. Bismuth precipitation from nitric solutions in the form of laurate and stearate allows efficient purification of bismuth from impurity metals. A comparison of bismuth extraction with di-2-ethylhexylphosphoric acid from nitric solutions in the form of solvated complex Bi(C16H34O2POO)3 • 2C16H34O2POOH and oxohydroxodialkylphosphate Bi6O4(OH)4(C16H34O2POO)6 is carried out. In the latter case, extracts concentrated with respect to bismuth can be obtained, which provides substantial broadening of the possibilities to use extraction-based processes in the technology of obtaining bismuth compounds.

The synthesis of amide complexes of O,O-di(alkyl)aryldithio phosphates of metals (Co, Cu, Zn) with acetamide, benzamide and salicylamide was carried out. It was found that one of the advantages of these amido complexes is the absence of odour amines and the possibility of their use in neutral, acidic and hydrocarbon media. The composition and structure of the obtained amido complexes were confirmed by analytical procedures and IR spectroscopy. The anticorrosion properties of preservation liquids based on the synthesized amido complexes with the spent turbine oil T-30 were studied on steel plates in three media: in a G-4 hydrochamber (temperature 40±2 °C, humidity 95±3 %); in seawater; in the 0.001 % solution of sulphuric acid. Their high efficiency against corrosion was revealed.

Dimethyl-, diethyl[1-allyl(3-α-naphthylprop-2-ynyl)]ammonium and -piperidinium bromides were synthesized by alkylation of dimethyl-, diethyl[1-allyl(3-α-naphthylprop-2-ynyl)]amines and -piperidine, obtained by Stevens rearrangement of dimethyl-, diethylallyl(3-α-naphthylprop-2-ynyl)]ammonium and -piperidinium bromides, with allyl or propargyl bromides. 2,2-Dimethyl-, 1-allyl-3 a ,4-dihydronaphtho[ f ]piperidinium bromides were obtained through base-catalyzed cyclization of dimethylallyl[1-allyl(3-α-naphthylprop-2-ynyl)]ammonium and -piperidinium bromides in the yields of 90 and 88 %, respectively. It is shown that the interaction of propargyl analogs with a catalytic amount of the base leads to the formation of compounds of unknown structure.

Predictive analysis of the state and course of works aimed at the construction of nanosized robots of different types and purposes is presented on the basis of literature and own sources of information. Two principally different methods of their construction are distinguished:
1. Molecular assembly or another manual version. The human factor is decisive here.
2. Alternative method. Nature itself creates the functional structures to govern nanotechnologies. The problem is in finding them and programming.
The first method turned out to be too complicated and attractive only in imagination, as in the saying: the devil is in the details.
The second method turned out to be great luck. On the basis of the available knowledge, the previously unknown natural phenomenon possessing the functional structure was found and decrypted. A physicochemical nanosized robot (PCNR) has been created, and the scientific basis of the technology to manufacture PCNR for different purposes have been established.