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The review article discusses the application of biogeochemical technologies aimed at restoring biogeochemical cycles in agroecosystems, primarily in the microbial link regulating CO2 flows. The factors of management this microbial link when applying mineral and organic fertilizers are shown. The processes of mineralization of soil organic matter and methods of controlling soil's conjugate carbon- and nitrogen-mineralizing ability are considered. The changes in the productivity of agricultural ecosystems under conditions of increasing concentration of carbon dioxide in the atmosphere and soil air are considered. Various agrotechnological techniques are considered, including using zero tillage, organic fertilizers of various nature, and various meliorants, including phosphogypsum. Examples of recultivation of disturbed and polluted soils, waterlogged and/or over-drained soils are given and the impact on CO2 fluxes is estimated. Based on numerous data, it is concluded that agroecosystems in most cases are a net source of CO2, and sequestration occurs only when agricultural land is transferred to fallow lands and at afforestation. At the same time, techniques aimed at reducing CO2 fluxes using fertilizers in the "production–application" cycle are evaluated. A set of biogeochemical technologies aimed at assessing and stabilizing the microbial link of the biogeochemical cycle in agroecosystems is presented. Examples of the use of these technologies for regulating CO2 emissions in agroecosystems are given. Using one of the biogeochemical technologies, the almost 5-fold decrease in the rate of CO2 flows during the reclamation of disturbed tundra ecosystems is shown. Adopting agricultural low carbon technologies (ALCTs) cannot yet testify to their applicability to ensure both food and environmental safety. It is necessary to further develop and use biogeochemical technologies to restore biogeochemical cycles in agroecosystems, primarily in the microbial link regulating CO2 flows.

A method has been developed for calculating the stability constants of inorganic complexes of rare-earth metals at various temperatures, based on analysis of the literature data by obtaining a linear regression equation on the form: . Using this method, the stability constants of bromide LnBr2+ and carbonate LnCO3+ complexes of europium, terbium, and gadolinium in aqueous solutions at temperatures of 50, 75, and 100 ° C were obtained. The obtained values of the coefficients А(T1) and В(T1) of the linear regression equation can be used to calculate the stability constants of complexes of europium, terbium, and gadolinium with other inorganic ligands at given temperatures. Based on the temperature dependence of the stability constants of bromide and carbonate complexes, their standard entropies and enthalpies of formation were calculated. Based on the obtained values of the thermodynamic functions, an assumption was made about the outer-sphere or inner-sphere nature of the complex.

Prospects for the development of Russia’s northern territories requires active improvement of existing and development of new regulatory documents regulating the usage of permafrost soils as underlying soil bases for buildings and structures. The introduction of new materials and technologies, the arrival of modern technologies, machines and mechanisms to the construction industry, has exacerbated the need to revise the civil engineering regulatory framework concerning permafrost conditions.

The article studies the most urgent problem of artificial intelligence (AI) - the development of a methodology for assessing trust in AI systems. A universal range of assessment is proposed: objective, subjective and intersubjective parameters. When studying the objective parameters of trust assessment, a formal definition of AI is introduced to increase the validity of trust judgments. When studying subjective parameters as the basis of expert evaluation indicators, their internal logical inconsistency is revealed along with demonstrating the significance of these parameters for analyzing the success and safety of methods for computer simulation of cognitive functions. When studying the intersubjective parameters of trust, a unified format of trust data is proposed, an interdisciplinary organization of monitoring trust in AI systems is considered, and the main blocks of an expert system project are formed.

To verify the mathematical model of the theory of processes, numerical calculations of the complex elastoplastic deformation of low-carbon steel 45 along multi-link strain trajectories with different corner angles under combined tension-compression with torsion were carried out. The numerical calculations are compared with the experimental data obtained by the authors on the SN-EVM testing machine on thin-walled tubular specimen. It is shown that the used mathematical model qualitatively and quantitatively satisfactorily describes the main effects of complex plastic deformation for the class of plane multi-link broken strain trajectories.

The study is aimed at expanding the scientific discussion about the factors of investment efficiency in regional (Russia) and sectoral (processing industry) projections. The paper presents the results of the research on the process of investing into innovations of the Russian processing industry (sample of 2009–2017). The factors of economic efficiency have been identified for investment industrial projects. The theoretical statement was formulated that in today’s economy, innovation investment efficiency is not determined that much by the internal potential of the enterprise and the infrastructure it is surrounded with (however, their significance in the balance of potentials is not denied), but rather by external, market factors - industry consolidation ratio on the platform of new technology innovation. The identified nature of innovation investment efficiency is considered as a new research statement, which has objective limitations: region- and industry-specific ones. The practical side of the obtained result can be formulated as a criterion for selecting industries (markets, lines of business) for investing into innovations by enterprises of the processing industry.

The luminescence properties of needle-like crystals of diamond, obtained by selective oxidation of textured polycrystalline diamond films, are studied. Diamond films were grown by chemical vapor deposition from a methane–hydrogen mixture activated by a DC discharge. The spectra of photo- and cathodoluminescence and the spatial distribution of the intensity of radiation at different wavelengths are obtained for individual needle-like crystals. Based on the spectral characteristics, conclusions are made about the presence of optically active defects containing nitrogen and silicon impurities in their structure, as well as the significant effect of structural defects on their luminescence spectra.

The active development of the Asia-Pacific region is often accompanied by geotechnical problems that require a rational solution. The article presents the results of a laboratory experiment that simulates the process of slurried pile construction in sandy frozen soils. The authors present the dependence of changes in the temperature of the soil and cement-sand mortar in time, defined the maximum radius of thawing and the total duration of the process of thawing and freezing back to the natural state, given the recommendations for the design of slurried piles taking into account thermal interaction with permafrost soils. The article presents a laboratory study of the interaction of auger cast piles with frozen soil. The results of laboratory studies of the strength of cement mortars of different compositions, hardened at a negative temperature. Recommendations on the choice of the solution composition for the installation of grout-injected piles in frozen soil are given. The article presents the state of the question of designing multi-blade screw piles, reflects the relevance of the development of methods of calculation and updating the regulatory framework. The authors carried out calculations of the bearing capacity of screw piles on various calculation schemes, the results of which are compared with field tests. As a result of comparison recommendations on the choice of the reliable settlement scheme are given. The authors believe that the solution of the problems identified in the article related to the use of advanced types of pile foundations in difficult geotechnical conditions will significantly improve the reliability of structures, reduce construction time and reduce economic costs.

This paper describes a classification method of brain signals measured from a subject during visual stimuli presentation. The method is based on exploring the features of visual event related potentials (VERP) in both time and spatial domains. Independent component analysis (ICA) is used for extracting the basic phase-amplitude features. A method for artifact rejection is proposed for excluding the noisy trials. A category-level classifier based on a neural network is trained and its performance on a publicly available database is evaluated and analyzed.

Single-crystal diamond microneedles were extracted from (001) textured polycrystalline films. The films were produced using a plasma enhanced chemical vapor deposition (CVD) from a CH 4 /H 2 gas mixture activated by a direct current discharge. The as-grown textured polycrystalline CVD films consist of pyramid-shaped micrometer size diamond crystallites embedded into a nanodiamond ballas-like material. The less ordered fraction of the CVD film material was removed selectively using thermal oxidation. A dependence of the diamond needle shape on the CVD and the oxidation process parameters was revealed via a computer simulation and experimental studies. Ability for mass production of the diamond microneedles of different shapes was demonstrated. The needles are suitable for various applications from microcutting tools to quantum information processing.

The objective of this research is to determine the most suitable software packages for simulation of thermal effect of various constructions on seasonally frozen or permafrost ground. The abrupt change in soil physical properties at freeze/thaw boundaries is a considerable challenge because it introduces a strong nonlinearity into the heat transfer model. Mathematically speaking, there appears a Stefan condition at the moving boundary of the phase transition. A problem of soil column freezing is considered. The simulation results, obtained by different software, are compared with the analytical solution of the corresponding semi-infinite Stefan problem. The frost penetration depth and the depth profiles of temperature and its absolute error, after 300 days, are presented.