bluuebunny/crossref_metadata_2025 huggingface dataset:
Disinformation and Propaganda in Russia’s Information Warfare. Concepts, Resources, Areas of Impact
Authors:   University of Szczecin, Orzechowski Marcin
Published: October 2024

Research objective – The aim of this article is to analyse the specifics of Russian information warfare. Starting from the definition of the concept of political strategy, the author tries to show that information warfare is one of the key instruments in the confrontation with Western states, and that the war in Ukraine has intensified Russia’s activities in this area, also towards Central European states. The means and tools used are an instrument for influencing the political and social processes taking place in other countries. Methodology – The study used a comparative method, collecting and analysing historical data and comparing theoretical approaches to categories such as political strategy, information warfare and hybrid warfare. Findings – The correlation analysis of Russian geopolitics and information warfare confirms that it is a dangerous weapon: a means of achieving the state’s goals in international, regional and domestic politics, as well as of ensuring its geopolitical superiority regionally and globally. Practical implications – This study aimed to organise and expand the available literature on the analysis of the specifics of Russian information warfare.
The People’s Republic of China in the Security Policy of the Russian Federation: The Evolution of Russian Strategic Documents in 2000–2023
Authors:   John Paul II Catholic University of Lublin, Składanowski Marcin , Smuniewski Cezary ,   University of Warsaw, Kopiec Piotr ,   John Paul II Catholic University of Lublin, Bado Błażej ,   University of Warsaw
Published: October 2024

This article provides a nuanced perspective concerning the future prospects of Sino-Russian security cooperation. It examines the image of China in Russian strategic documents during President Putin’s rule and investigates potential points of conflict arising from Russia’s perception of the post-Soviet landscape as its exclusive sphere of influence. The study is based on a systematic analysis of Russian strategic documents, specifically focusing on how they address of Sino-Russian relations, as well as Russian security and foreign policy concerning Central Asia. The analysis reveals that actual Russian security policy exhibits caution in its cooperation with China. The research contributes to the field by delineating a significant discrepancy between the role ascribed to China in Russian state propaganda, and therefore in public perception, and the more measured and reasonable formulations present in Russian strategic documents. This divergence illustrates the complexity and caution that characterise genuine Sino-Russian relations, especially in the realm of security policy.
Energy Infrastructure Cooperation Between China and the Caspian Region States
Authors:   Maria Curie-Skłodowska University in Lublin, Misiągiewicz Justyna
Published: October 2024

This study’s research problem is the determinants, evolution and implementation of cooperation in the energy dimension between the Caspian states of Central Asia (Kazakhstan and Turkmenistan) and the People’s Republic of China (PRC). Pipeline routes are determined considering economic conditions, but are also the result of geopolitical actions of the states. The study aims to verify the research hypothesis that the specificity of cooperation in the energy field between the Caspian states and China is conditioned by objective economic interdependencies, but also results from geopolitical conditions. A predictive approach, related to the future role of the Caspian region in the energy market, was taken into account. A factor method was used in the analysis to identify the determinants of cooperation in the energy dimension between the Caspian states and China. A theoretical approach useful in solving the research problem is the geopolitical (geo-energy) approach and the theory of complex interdependence.
Green synthesis of CdFe2O4 by Terminalia catappa leave extract for photodegradation methyl red dye by response surface methodology
Authors: Hariani Poedji Loekitowati , Salni Salni , Yusmartini Eka Sri , Aprinati Nabila , Ahadito Bijak Riyandi
Published: October 2024

Green synthesis using plant extracts is an eco-friendly approach that reduces the hazards associated with chemical usage. This study aimed to synthesize a CdFe2O4 ferrite compound utilizing Terminalia catappa leaves extract and evaluate its photocatalytic efficiency in degrading Methyl red dye. The X-ray diffraction (XRD) analysis confirms the synthesis of CdFe2O4, which has a crystallite size mean of 18.10 nm. The composite exhibits magnetic properties with a saturation magnetization of 28.34 emu/g, a band gap of 1.78 eV, and a BET surface area of 84.23 m2/g. The optimal photodegradation process was determined using Response Surface Methodology (RSM) based on an experiment with Central Composite Design (CCD). The variables examined included the solution pH, the initial concentration of the dye, and the irradiation time. The interplay of three variables demonstrated their reciprocal influence on photodegradation efficiency. The quadratic model is appropriate for modeling the photodegradation of Methyl red dye. The photodegradation efficiency of 96.56% is achieved under optimal conditions, which include a pH of 6.33, an initial dye concentration of 39.93 mg/L, and an irradiation time of 52.26 min. Empirical investigations on the reusability of CdFe2O4 have shown remarkable stability. Experimental kinetics confirm that the pseudo-first-order model is a suitable description for the photodegradation of Methyl red dye by CdFe2O4.
The novel Zn-doped hexagonal perovskite Ba7In6Al2O19: electrical conductivity and hydration
Authors: Animitsa Irina , Korona Daniil , Bushueva Arina , Andreev Roman , Nokhrin Sergey
Published: October 2024

The novel phase Ba7In5.9Zn0.1Al2O18.95 with hexagonal perovskite structure was obtained by solid-state technique. The substitution of In3+ by the Zn2+ leads to the expansion of the lattice parameters and cell volume. It was established that the investigated sample is capable of water incorporation from the gas phase; the degree of hydration reaches 1.42 mol H2O, which is significantly higher than that for the undoped phase (0.41 mol H2O). This is a result of the expansion of the hexagonal layer that facilitates the placement of OH–-groups. The oxide-ion and proton conductivities for the doped Ba7In5.9Zn0.1Al2O18.95 sample were higher than those for the undoped composition, Ba7In6Al2O19, by 0.50 and 0.75 orders of magnitude (500 °C), respectively. The new phase Ba7In5.9Zn0.1Al2O18.95 demonstrates the predominant protonic conductivity at Т ≤ 500 °C and pH2O = 1.93·10−2 atm.
Specifics of modern fishery of marine fish in the coastal zone of Kunashir Island
Authors: Zolotov A. О.
Published: October 2024

Specifics of coastal fishery and species composition of marine fish communities in the sublittoral zone during spring-summer period is considered based on the results of studies of the composition of commercial catches by fixed nets and Danish seines in the coastal zone and on the shelf of Kunashir Island in 2021–2023, analysis of seasonal and annual catch statistics in 2014–2023 and archival materials. It is shown that the species composition of catches in the coastal zone includes up to 30 species of fish from 13 families. The most diverse were Flounders – 8 species (26.7%), Sculpins – 5 species (16.7%) and Greenlings – 4 species. Saffron cod, whitespotted char, Pacific herring, starry flounder, cresthead flounder, toothed smelt and arabesque greenling were the most widespread. These species contributed between 67.2 and 99.9% into the total catch weight. The Saffron cod formed the basis of the fixed net catches on the Pacific coast. Its contribution ranged from 84.7 to 86.5%. The contribution of cresthead flounder varied in the range of 4.1–7.9%, of starry flounder – 1.1–3.9%, of whitespotted char – 1.2–2.3%, of toothed smelt – 4.1–0.7%. Cresthead flounder dominated (28.7%) on the coast of the Sea of Okhotsk in terms of biomass. The contribution of saffron cod and whitespotted char – both were about 19.7%, of Pacific herring – 18%. According to the fishery statistics obtained from processing plant, the composition of the catch in 2014–2023 corresponds well to the results of the analysis of species composition of the catches according to scientific observations. The main commercial object was saffron cod with average contribution into the annual catch of 75.1%. Flounders contributed 15%, herring – about 4.5%, the other species can be considered as by-catch. About 83.2% of the annual catches by fixed nets in 2014–2023 were obtained on the Pacific coast of Kunashir Island and only 16.8% – on the coast of the Sea of Okhotsk. Obtained results can be used for stock abundance assessment, evaluation of the allow- able catches of marine fish in the South Kuril zone and planning expeditionary researches.
Catches, distribution and main biological indicators of walleye pollock in trawl catches in the north-eastern part of the Sea of Okhotsk in the fall-winter period
Authors: Varkentin A. I.
Published: October 2024

Based on data from the industry system of monitoring of aquatic biological resources, observation and control over the activities of fishing vessels for 2008–2022, the article provides information on the total catch of walleye pollock in the northeastern part of the Sea of Okhotsk, including by season and during the specialized trawl fishery. According to the data collected by scientific observers on fishing vessels in October–December 2009–2011, 2019, 2021–2022, data from the industry monitoring system for the same years, the distribution of catches, the intensity of specialized trawl fishing, size-age composition of walleye pollock are studied.
Experimental obtaining the polyploid Pacifi c oyster Crassostrea gigas (Thunberg, 1793) via a heat shock
Authors: Leskova S. E. , Sinenko A. V. , Anisimova A. A. , Kovalev N. N.
Published: October 2024

Method of thermal induction was tested for the first time in the practice of Far Eastern aquaculture to obtain polyploid Pacific oyster Crassostrea gigas. Experimental blocking of meiosis was performed 25 min after fertilisation by brief (3 min) exposure to the temperature of 32 oC. Efficiency of the method was evaluated with assessment of survival, growth and development of control and experimental larvae (groups 2N and 3N, respectively) in conditions of plant. Growth rate of juvenile Crassostrea gigas in Voyevoda Bay, Russky Island (Peter the Great Bay, the Sea of Japan) during two years was studied also. The content of DNA in haemocytes evaluated using flow cytometry revealed 35% triploids, 22.5% tetraploids and 40% heteroploids in the group 3N. The maximum weight increment in this group (0.34 g/day) was observed in summer at the second year of life, and the maximum linear growth rate (1.55 mm/day) – in September at the second year. The values for the group 2N were 0.31 g/day and 1.47 mm/day respectively. After 22 months, 57.9% of diploid and 80.9% of polyploid oysters reached their commercial size. The total weight of oysters in the group 3N was 124.6 ± 2.7 g, what was 43% more compared to the group 2N.
Analysis of the nothern shrimp fi shery in the south-eastern part of the Sea of Okhotsk in 2018–2022
Authors: Mikhaylova O. G.
Published: October 2024

The article updates information on the northern shrimp fishery since 2017. Averaged daily reports from vessels from the industry monitoring system of Rosrybolovstvo were analyzed. Results obtained from vessels in the course of fishery monitoring in 2018–2019, 2022 were added. It is found out that, similarly to previous years, the main fishing period falls on the winter-spring period with maximum catches in March– April. The proportion of the catch at this time reached 70% of the TAC. The fishery was mainly conducted at depths of 300–400 m, where, according to data obtained during the fishery monitoring, the highest abundance rates were observed. In autumn, the catch did not exceed 0.1–13% of the TAC, depending on the year of fishing. According to the ship’s daily reports, there has been an increase in average daily catch in recent years from 2.8 in 2018 to 4.5 tons in 2022. The quantitative and qualitative composition of the catches in recent years has been at the same level as in previous years, with all averages remaining at the same level.
Conceptual metaphors in international agreements representing ecological discourse (as exemplified in protocol on strategic environmental assessment in Russian, English and French)
Authors: Kurganova Margarita
Published: October 2024

This study investigates the role of metaphorical concepts in shaping the interpretation of the Protocol on Strategic Environmental Assessment (2003), an annex to the Convention on Environmental Impact Assessment in a Transboundary Context. Analyzing the English, French, and Russian versions of the Protocol, the study identifies and analyzes the presence and function of ontological and orientational metaphors, examining their potential influence on the parties' understanding of the document's provisions. Through a comparative linguistic analysis, the study explores language-specific variations in metaphorical expression and investigates the role of metaphorical conceptualization in fostering cross-cultural communication within the context of international environmental law. The findings, presented systematically in a table, contribute to a deeper understanding of the interplay of language, metaphor, and legal discourse, offering practical implications for teaching socio-political translation, intercultural communication, and English and French language instruction.
Theory of the multi-level nature (multi-levelness) of a business model, business modeling and business model innovation in strategic management
Authors: Kolyada Andrey
Published: October 2024

The purpose of the research, the results of which are presented in this article, is to present the main theses of the theory of the multilevel nature (multi-levelness) of a business model created by the author within the framework of scientific work in the field of business modeling and strategic management. The article is a logical continuation of the author's scientific research presented earlier, within the framework of which a review of foreign and Russian scientific works in the field of business model innovation and definition of the concept of a business model was carried out, the hypothesis of multilevel business model was put forward, the author's universal intersectoral methodology for developing an organization's business model and forecasting its economic efficiency was presented. The material presented in this article is based on a long-term empirical analysis obtained during observations of the activities of organizations in various industries in Russia and abroad, and contains a theoretical basis describing the object of the formulated theory — a multilevel business model of the organization — and related postulates. The theses defining the theory of the multilevel nature of the business model are formulated: the primacy of the business model of the organization over its strategy is stated; the multilevel nature of the business model is described (holding, corporate and product-market levels are highlighted); the implementation of business modeling and business model innovation (BMI) is justified by levels, and not in relation to the business model as a whole; the recommended focus or starting point of business modeling / BMI is determined. The theoretical theses are accompanied by the necessary explanations and are supported by the evidence base. The theoretical findings and methodological solutions proposed in this study solve the problem of the practical applicability of the business model concept and systematize the process of business modeling and business model innovation.
Entre a história antiga amazônica e seu presente etnográfico: colonialismo e persistências nas trajetórias indígenas de longa duração do médio Solimões, Amazonas
Authors: Lopes Rafael de Almeida , Almeida Fernando Ozorio de , Tamanaha Eduardo , Neves Eduardo Góes
Published: October 2024

Resumo No presente artigo, propõe-se um diálogo entre registros históricos e arqueológicos da Amazônia, partindo da história indígena de longa duração do médio Solimões, em especial de seu último período associado às ocupações da Tradição Polícroma da Amazônia (TPA). Para isso, tratamos da história das relações entre fontes escritas e dados arqueológicos na Amazônia, notando como a arqueologia do colonialismo e a arqueologia documental podem fortalecer a compreensão contextual do registro arqueológico e elucidar o período mais tardio das ocupações associadas à TPA na região. Em seguida, apresentamos brevemente os contextos e as fontes analisadas, os métodos utilizados, assim como os resultados obtidos. A pesquisa se estende até o início do século XX, mas maior enfoque é dado ao estudo dos séculos XVI a XVIII. Na discussão, o objetivo é o de reavaliar a própria história da TPA e suas periodizações. A conclusão leva a um debate sobre rumos para expandir as possibilidades do diálogo entre história, arqueologia e etnologia da Amazônia e sobre a arqueologia do colonialismo amazônico.
Re-examination and analysis of test data on consolidation of soft soils exhibiting creep with different thicknesses
Authors: Wu Pei-Chen , Chen Ze-Jian , Yin Jian-Hua , Watabe Yoichi , Song Ding-Bao , Li Peng-Lin
Published: October 2024

Accurate prediction regarding the long-term settlements of soft soils is challenging. One of the reasons for this is time-dependent soil behaviours. How to extrapolate such behaviours from thin laboratory testing with limited timescales to an in situ thick soil layer with large timescales is still an ongoing debate, which can be dated back to the work of Ladd and co-workers in 1977. Many experimental results that were previously used to advocate hypothesis A have been re-analysed and found to align with hypothesis B. However, discrepancies remain in some historical data, particularly in the case of Osaka clay retrieved from the seabed under the Kansai international airport islands. This study begins by introducing the main implications and selected existing models for the time-dependent behaviours of soft soil. It then focuses on the re-examination of selected test results from the work of Watabe and co-workers in 2008, supplemented by numerical simulation using isotache models. The analysis emphasises the importance of considering equal initial conditions when comparing data from samples with varying thicknesses. Furthermore, the good agreement observed between measured data and the simulation results using hypothesis B methods demonstrates the validity of hypothesis B for predicting the long-term consolidation behaviour of soft soil both in the laboratory and at field scales.
Methodological Approach to the Efficiency Analysis of Regional Industrial Ecosystems
Authors:   MIREA - Russian Technological University, Mityakov E. S. , Mityakov S. N. ,   Nizhny Novgorod State Technical University named after R.E. Alekseev
Published: October 2024

Formation of a new model of limited open sovereign economy in Russia requires the improvement of the theoretical and methodological basis for evaluating the efficiency of regional industry. The research aims to develop a methodological approach to the efficiency analysis of regional industrial ecosystems. To this end, an ecosystem approach to analysing the efficiency of regional industry was employed. In order to establish evaluation criteria, the study defined the structure of regional industrial ecosystems, comprising a set of intrinsic characteristics (development projections): scale, production potential, production infrastructure, human capital, research and development (R&D), innovation, integration potential, competitiveness, and ecology. Efficiency evaluation and comparative analysis of regional industrial ecosystems were performed using a developed system of twenty-seven indicators to provide an objective assessment of the state of industry. The paper examined five industrially developed regions of the Volga Federal District: the Republics of Bashkortostan and Tatarstan, Perm krai, Nizhny Novgorod and Samara oblasts. Testing of the authors’ approach revealed the uneven development of regions according to projections and indicators of industrial ecosystems. Nizhny Novgorod oblast achieved the best result in terms of the totality of indicators, as well as in terms of scale and production potential, R&D and ecology. Perm krai is a leader according to such indicators as production infrastructure and product competitiveness. The Republic of Tatarstan leads in innovation, while the Republic of Bashkortostan has the greatest integration potential. Samara oblast is the outsider characterised by high depreciation of fixed assets and discharge of contaminated wastewater. The findings confirmed the research hypothesis about the possibility of representing processing industries of industrially developed Russian regions as industrial ecosystems.
Methodology for Measuring Housing Affordability
Authors:   Kostroma State University, Ivanitskiy V. V.
Published: October 2024

As the basis of many social institutions, family greatly contributes to regional and national development. Housing affordability is an indicator of the standard of living in a region, which ultimately determines its ranking. The paper proposes to use the housing affordability coefficient, based mainly on the stages of creation and development of a social unit (family), which considers the influence of life circumstances (obstacles) on purchasing a house by a particular family in a particular region. This indicator includes two components: a constant of the period of savings accumulation by the family from the beginning of pregnancy until the child reaches the age of 1.5 years and the mortgage period. The housing affordability coefficient was tested on data for the Russian Federation, as well as for two regions of the Central Federal District (with the lowest and highest housing costs). The paper emphasises that the index of real estate affordability should have a specific value that can be perceived and imagined. The article provides a comparative analysis of the author’s and generally accepted in Russia methods of analysis for the period 2006–2021. A significant improvement in housing affordability was observed at the end of the examined period due to the presence and increase in maternity capital, the permission to use it as a down payment, the reduction by banks of the down payment and the mortgage rate. The author’s methodology more clearly confirmed the hypothesis that life circumstances (obstacles) greatly affect housing affordability, significantly increasing the values of the housing affordability coefficient. The findings can be used to compile a regional ranking in general and to assess the regional housing sector in particular.
Effects of a Customs Union on Economic Growth: Empirical Evidence from Southern African Customs Union (SACU)
Authors:   RUDN University, Lee H.-S. , Chernikov S. U. ,   RUDN University, Moseykin Yu. N. ,   RUDN University, Barrie G. ,   RUDN University
Published: October 2024

This study analyses the effects of the Southern African Customs Union (SACU) on the economic growth of its member states based on unbalanced panel datasets. This research was inspired by the ongoing discussions about the development of “free-trade agreements” and the growing anxiety about the US dollar’s stability as a world currency. The latter has recently led to the announcement of the Brazil-Argentina currency union to make bilateral trade easier. As the SACU countries are practically using the South African Rand as a single currency, a growing interest in evaluating the SACU internal trade validity for being the foundation of similar integrative action has started to manifest. The regression results of pooled ordinary least squares (OLS), fixed effects (FE), and random effects (RE) models demonstrate that the economic growth effects of intra-trade (exports, imports) of SACU do not exist. This indicates that further economic integration may not provide positive effects for SACU. However, the most crucial factor to drive the economic growth of SACU turned out to be domestic investment. Attracting foreign direct investment (FDI) also highly contributes to the economic growth of SACU. It is natural and advisable for the member states of SACU to continue the enhancement of investment-conducive environments for domestic and foreign companies. In addition, the long-term fuelling of economic growth with government debt, government spending, and investments points to possible discrepancies in the economic structure of the union, may be connected to internal demand issues. In this sense, it would be reasonable to research the potential of expanding SACU to the countries of the Southern African Development Community (SADC).
Regional Insurance Markets of the Russian Federation: Development Dynamics in the Post-COVID Period
Authors:   Saint Petersburg State University, Belozerov S. A. , Romanova A. B. ,   Interregional Consumer Mutual Insurance Society
Published: October 2024

The continuing interest in the insurance market of both experts in the field and ordinary citizens who need insurance services highlights the importance of analysing the impact of the COVID-19 pandemic consequences, which significantly affected the activities of insurance market participants in 2021. While the insurance market has largely overcome the negative effects of the pandemic, its consequences still influence the market’s development. The analysis of changes will help develop theoretical and practical recommendations to minimise the consequences of biological threats in the future. The study aims to assess the insurance market in the post-COVID period based on the results of insurers’ activities in 2021 by types of insurance in federal districts of the Russian Federation and to determine development dynamics, the degree of penetration and the need for insurance services in regions. To this end, official statistics were used to examine insurers’ activities by comparing and summarising metadata, considering regional characteristics of the constituent entities of the Russian Federation. It is hypothesised that while emergency conditions affect all sectors of the economy and the social sphere, the insurance market remains stable and quickly adapts to changes. The study concluded that all types of voluntary and compulsory property insurance are presented in the Russian insurance market; in comparison with the pre-COVID period, the insurance sector showed an increase of 17.46 %; a positive trend of increasing fees in almost all regions indicates an increase in the penetration of insurance services. The global events of 2022 have also seriously affected the insurance industry, thus, it can be expected that the insurance sector will undergo a significant transformation in the future.
Methodological Approach to Assessing the Impact of External Factors on Financial Risks of Retailers Considering Regional Aspects
Authors:   St. Petersburg University of Management Technologies and Economics, Kunin V. A. , Peshko S. I. ,   St. Petersburg University of Management Technologies and Economics, Rumyantseva A. Yu. ,   St. Petersburg University of Management Technologies and Economics
Published: October 2024

Financial risk management in retail companies requires considering both internal and external risk factors. Contemporary researchers primarily focus on macroeconomic indicators disregarding regional aspects that might exacerbate key financial risks for multi-regional enterprises. The study aims to develop a methodological approach to assess and predict the impact of mesoeconomic factors on financial risks of retailers. Particular attention is paid to downside (profit and profitability) and structural risks. The presented approach implements the authors’ concept based on the application of correlation-regression analysis of relationship between retail trade turnover of these companies and external factors. The study employs mathematical statistics and econometric analysis. Publicly accessible official data from the Federal State Statistics Service, the Central Bank of the Russian Federation and the United Nations for 2005–2021 were analysed. The research investigates changes in profit, profitability and combined leverage (which combines financial and operating leverage) affected by external factors. The proposed methodology for assessing the impact of external factors on financial indicators revealed their heterogeneous effect on retail trade turnover depending on the region. The study introduced a novel integrated leverage metric and its analytical estimates, which quantify the impact of external factor variations on profit and profitability of retail companies. The proposed methodology and resulting estimates can be used by financial, investment and managerial decision-makers to identify external factors affecting financial risks of companies at the meso level. The study contributes theoretically by developing a methodological approach to assessing and predicting financial risks considering regional aspects.
Hydrometallurgical recovery of nickel from oxidized ores
Authors: Dudarev V. I. , Dudareva G. N. , Yakovleva A. A.
Published: October 2024

A significant portion of the world’s reserves of Ni-containing raw materials (40–66 %) is concentrated in oxidized nickel ores. One of the alternatives to the high-cost pyrometallurgical and ammonia-carbonate methods for processing such ores could be the chlorammonium recovery of nickel from relatively low-grade ores. The halide-ammonia decomposition and recovery technology of nickel from oxidized nickel ores, supplemented by a sorption process, is less stage-intensive and simpler in practical implementation. Nickel adsorption recovery is feasible using carbon sorbents that exhibit high chemical stability, withstand high-temperature exposure, and strong acidic treatment. Sorbents were obtained through steam-gas activation of extracted carbonizates from fossil coals. The sorption capacity for Ni(II) ions was studied, and the patterns and characteristic parameters of the process on carbon sorbents were identified using adsorption isotherms while varying experimental conditions. The experimental results were processed using the Freundlich and Langmuir equations. The sorbents have several distinctive features determined by their predominant microporous structure and multifunctional surface with active complex-forming atomic groups, characteristic of ampholytes with cation- and anion-exchange properties. The adsorption process is described by a pseudo-first-order equation with rate constants ranging from 0.204 to 0.287 s–1. For the adsorption recovery of Ni(II), a scheme with two adsorbers and a pseudo-fluidized sorbent bed is proposed. Nickel desorption and sorbent regeneration were carried out with a 2.3 % sulfuric acid solution, desorbing 95 to 98 % of nickel. Standard chemical machinery and equipment are recommended for these processes.
Development and solution of the kinetics equation and adsorption isotherm for gold adsorption from cyanide solutions onto activated carbon
Authors: Elshin V. V. , Mironov A. P. , Lisitsyna A. A.
Published: October 2024

This paper presents the results of theoretical and experimental studies on the process of gold adsorption from cyanide solutions onto activated carbon (AC). One of the objectives of the study was to identify the functional relationship between the mass loading of AC in the volume of the adsorption column solution and the kinetics of the process. To achieve this, a modified adsorption kinetics equation (considering the heterogeneity of the process) was proposed, which incorporates the solid phase of the carbon sorbent in the unit volume of solution as a third intermediate agent of adsorption interaction between the adsorbate ions and the free active sites of the AC. As a result, a modified third-order adsorption kinetics equation for gold adsorption on AC was derived, taking into account the solid phase loading of AC in the solution volume, along with its analytical solutions under conditions of constant gold content in the initial solution and the process conducted in a closed volume with varying gold concentrations in the solution according to the material balance equation. The relationship between the solutions of the kinetic equation and the adsorption isotherm equation was established. From the solutions of the kinetic equation, a modified Langmuir isotherm equation was derived, which allows determining the equilibrium concentrations of gold on the AC and in the solution a priori under the condition that the process is conducted in a closed volume, with known initial gold contents in the solution and on the AC, as well as with a known AC loading in the adsorber volume. The theoretical dependencies of the adsorption and desorption rate constants on temperature, convective, and diffusion parameters are discussed. The presented mathematical model of adsorption kinetics is valid under the conditions of gold adsorption on AC from gold cyanide solutions with an adsorption time of up to 2 days and a sorbent capacity utilization degree of 40–60%.
Finite element simulation of hot cladding parameters for thin-sheet rolled products made of experimental Al–2%Cu–2%Mn alloy
Authors: Koshmin A. N. , Zinoviev A. V. , Cherkasov S. O. , Tsydenov K. A.
Published: October 2024

An analysis was performed on the temperature, rate and force parameters of the hot cladding process for the experimental Al–2%Cu–2%Mn alloy with technically pure aluminum grade 1050A, as well as on the stress-strain state of the metal in the deformation zone at reductions of 30, 40, and 50 %. Plastometric tests were conducted within the temperature range of 350–450 °C, strain rates of 0.1–20 s–1, and true strain of 0.1–0.9, and coefficients for calculating the flow stress of the experimental alloy were determined. The thermal conductivity of the Al–2%Cu–2%Mn alloy under hot deformation conditions at temperatures of 350, 400, and 450 °C was theoretically calculated to be 161, 159, and 151 W/(m·K), respectively. The study of the cladding process on a two-high rolling mill was carried out using the QForm finite element simulation software. It was found that when the metal of the cladding layer comes into contact with the roll, its temperature decreases by approximately 100 °C, with the temperature across the height of the composite equalizing within 20–30 ms after exiting the deformation zone. The rolling force is evenly distributed between the two rolls in all cases considered, while the rolling torque on the roll on the cladding layer side is half that on the roll contacting the base layer, which is characteristic of asymmetric rolling. Points characterized by optimal bonding conditions of the rolled layers were identified, located at 10 % and 70 % of the deformation zone length along the rolling axis, where normal stresses significantly prevail over shear stresses. It was determined that the formation of these areas is due to the nature of plastic flow, including the presence of a non-deforming hard layer and a sticking zone.
Thermodynamic modeling of cobalt and nickel reduction using hydrometallurgical enrichment concentrates for steel alloying
Authors: Rybenko I. A. , Nokhrina O. I. , Rozhikhina I. D. , Golodova M. A.
Published: October 2024

The article provides studies on reduction processes in model thermodynamic systems and processes of nickel reduction from nickel concentrate and cobalt and nickel from cobalt-nickel concentrate. Concentrates are obtained during hydrometallurgical enrichment of polymetallic manganese-containing ores of the Kemerovo region – Kuzbass. By thermodynamic modeling using TERRA software complex, it was determined that nickel can be completely reduced from oxide in the NiO – C system at a carbon consumption of 0.08 kg/kg NiO, and at a carbon consumption of 0.15 kg/kg NiO ‒ in the NiO – Fe2O3 – C system. It was found that cobalt reduction in the CoO – C system begins at a temperature of about 513 K at any carbon consumption. With a further increase in temperature, the reduction process depends only on consumption of the reducing agent. From the obtained thermodynamic modeling data, it follows that cobalt reduction from the cobalt-nickel concentrate begins at a temperature of about 513 K and subsequently depends slightly on temperature. The extraction of cobalt increases with the amount of reducing agent at temperatures up to 553 K, then remains constant up to 1473 K temperature. Nickel reduction takes place at a temperature above 473 K. The degree of nickel reduction slightly depends on the temperature and amount of reducing agent at consumption of the latter over 0.02 kg/kg of concentrate. Laboratory studies showed that during the melting period, nickel can be reduced from its oxide almost completely with solid carbon, since nickel has less sensitivity to oxygen than iron. Theoretical and experimental studies of steel direct alloying showed that it is advisable to use a solid phase process in reduction of nickel and cobalt. Nickel concentrate and cobalt-nickel concentrate during steel smelting in an electric furnace is advisable to be introduced into charge in the form of mixtures pelletized with a carbonaceous reducing agent.
Complex electron-ion-plasma surface modification of high-alloy stainless steel
Authors: Ivanov Yu. F. , Petrikova E. A. , Teresov A. D. , Lopatin I. V. , Tolkachev O. S.
Published: October 2024

The work is devoted to identification and analysis of patterns of change in the elemental and phase composition, defective substructure, mecha­nical (microhardness) and tribological (wear resistance and friction coefficient) properties of stainless high-chromium steel subjected to complex processing, combining vacuum irradiation of the samples surface layer with an intense pulsed electron beam of submillisecond exposure duration and subsequent nitriding under electron-ionic heating conditions. High-chromium steel AISI 310S, which in the initial state is a polycrystalline aggregate based on γ-iron, was used as the research material. Pulsed electron beam treatment of steel was carried out on a “SOLO” installation equipped with an electron source with a plasma cathode based on a low-pressure pulsed arc discharge with grid stabilization of the cathode plasma boundary and an open anode plasma boundary. Steel nitriding was carried out on a “TRIO” installation with a chamber size of 600×600×600 mm, equipped with a switching unit to implement the electron-ionic processing mode. Nitriding was carried out at 723, 793, and 873 K temperatures for 1, 3 and 5 h. It was found that electron-ionic nitriding of the samples pre-irradiated with an electron beam (10 J/cm2, 200 μs, 3 pulses at 723 and 793 K for 3 h) is accompanied by the formation of a ceramic layer containing only iron and chromium nitrides. The highest values of steel wear resistance after electron-ionic nitriding, exceeding the wear resistance of the initial steel by more than 700 times, are observed at nitriding parameters of 793 K, 3 h.
Phase composition and microstructure of intermetallic alloys obtained using electron-beam additive manufacturing
Authors: Astafurov S. V. , Mel’nikov E. V. , Astafurova E. G. , Kolubaev E. A.
Published: October 2024

The paper investigates the microstructure and phase composition of nickel- and aluminum-based intermetallic alloys obtained using two-wire electron-beam additive manufacturing (EBAM). Relevance of the research is related to the widespread use of intermetallic alloys based on nickel and aluminum (mainly Ni3Al) in various high-temperature applications and the need to use modern production methods when creating machine parts and mechanisms from these alloys. Using EBAM, the billets from intermetallic alloys with different ratios of the content of main components were obtained. Change in concentrations of the basic elements was carried out varying the ratio of feed rates of nickel and aluminum wires during additive manufacturing in the range from 1:1 to 3:1, respectively. The results of microscopic studies of the obtained alloys showed that, regardless of nickel content, the obtained alloys are characterized by a large–crystalline structure with grain sizes in the range of 100 – 300 μm for alloys with a component ratio of 1:1 and 150 – 400 μm for alloys with a component ratio of 2:1 and 3:1. At the same time, the alloy with an equal content of base components is characterized by more uniform grain and microstructure compared to those with high content of Ni. By changing the concentration ratio of the components, phase composition of the resulting billet can be purposefully controlled. In the case of an “equiatomic” content of the base components in the alloy, a NiAl-based compound with a small phase content based on the intermetallides Ni3Al5 and Ni3Al is formed. At high concent­rations of nickel, the intermetallic Ni3Al phase is formed, and at a component ratio of 3:1, structure of the resulting billet consists mainly of Ni3Al phase and the γ solid substitutional solution based on nickel. The paper demonstrates the possibility of direct production of intermetallic alloys with a given phase composition during electron-beam additive manufacturing.
Low-cycle fatigue of welded joint from steel of X70 strength class
Authors: Galkin A. A. , Kabaldin Yu. G. , Mordovina Yu. S. , Anosov M. S.
Published: October 2024

Steels of X70 strength class are particularly widely used in the field of heavy engineering. One of the most important issues when choosing steel for structures is its behavior under cyclic loads. It is difficult to find a description of the behavior of all zones of the welded joint under fatigue. The purpose of this study was to determine the fatigue characteristics of welded joints made of the Russian analogue of S690QL steel with fixation of acoustic and magnetic parameters for their use in the diagnosis. The objects of the study were the samples from domestic steel of X70 strength class. The chemical composition was determined using optical emission spectrometry. The grinds for microstructural analysis were prepared according to the standard technique with etching in the metal. The fatigue test was carried out on a specialized test bench. The authors used the acoustic system AIS NRK-3 for acoustic measurements and the acoustic parameter D – as an informative parameter. A MA-412MM coercitimeter was applied to evalua­te the magnetic characteristics. The following were evaluated: residual magnetization Br , coercive force Hc , Hc/Br ratio. The smallest number of cycles corresponds to the deposited metal zone. The decrease in amplitude showed a significant variation in the behavior of the material depending on the junction zone. However, the curves for heat affected zone (HAZ) and the deposited metal are practically the same. HAZ differs to a lesser extent from the base metal than the deposited metal zone. The graph of the acoustic parameter in its form is the reverse of the magnetic characteristics graph. Thus, there is a minimum for the acoustic parameter, depending on the operating time, and a maximum for the magnetic characteristics. For both graphs, the extremum is the point corresponding to the operating time of 0.6.
Physics of hardening of the rolling surface of rail head from hypereutectoid steel after operation
Authors: Popova N. A. , Gromov V. E. , Yur’ev A. B. , Martusevich E. A. , Porfir’ev M. A.
Published: October 2024

In Russia, with its extensive railway system, for more than 5 years, special-purpose rails of increased wear resistance and contact endu­rance of the DH400RK category were produced from steel with a carbon content >0.8 %. On the head rolling surface of differentially hardened long rails made of hypereutectoid steel after long-term operation, transmission electron microscopy methods revealed the morphological components of the structure: lamellar pearlite, fragmented pearlite, destroyed lamellar pearlite, globular pearlite, completely destroyed pearlite, subgrain structure. The contribution of hardening due to: lattice friction, solid solution hardening, pearlite hardening, incoherent cementite particles, grain boundaries and subboundaries, dislocation substructure and internal stress fields were quantified. A hierarchy of these mechanisms was made and it was noted that for the fillet surface of the rail head, the main hardening mechanism is hardening by incoherent particles, as well as mechanisms caused by internal long-range (local) stresses, internal shear stresses (“forests” of dislocations) and substructural hardening. For the rolling surface along the central axis of the rail head, the main role in hardening belongs to long-range stress fields (especially its elastic component), hardening by incoherent particles and substructural hardening. Taking into account the volume fractions of the morphological components and their yield strength, the additive yield strength on the head rolling surface in the center and on the fillet was determined: 7950 and 2218 MPa, respectively. The paper presents a physical interpretation of the difference in values of the additive yield strength on the rolling surface of the rail head in the center and on the fillet.
Effect of electric arc surfacing on the structure and properties of coatings
Authors: Shlyakhova G. V. , Danilov V. I.
Published: October 2024

Surfacing, like welding, is associated with heating metals in a wide range of temperatures and subsequent cooling of heated zones at different rates. This leads to complex structural and phase changes that are crucial for operational properties of the “protected material – coating” joint. The structure and properties of the alloyage zone of these two materials depend on the degree of penetration, nature of the intermediate layers that arise, and carbon diffusion in the boundary areas. When surfacing on low-carbon steel, depending on the composition of the deposited metal, the structures with a predominant amount of martensite or austenite can be obtained in the alloyage zone, depending on carbon content. The structure and mechanical properties of the bimetallic joint between carbon steel and stainless steel were studied depending on the modes of electric arc surfacing (submerged arc surfacing in one pass, in argon for one and two passes). It was established that the structural and phase composition of the deposited metal is austenite, finely dispersed carbides and a needle component. The structure of the layer deposited in argon in one pass is more homogeneous and does not contain defects. The microhardness increases smoothly along the depth of the deposited layer. As a result of surfacing in argon in two passes, the joint has a homogeneous microstructure, but a large number of microdefects are formed in the layer, which can further lead to the formation of a crack near the alloyage boundary. In submerged surfacing, the heating rate and specific heat input are insufficient, therefore, the surfacing bath is poorly mixed, which leads to a suboptimal structure and the formation of thermal stresses at the alloyage boundary and to the formation of a coating that is heterogeneous in structure and microhardness.