The effect of spruce plantation density on resilience of mixed forests in the Perm Krai

Over the course of the last few decades, many countries across the globe have experienced mass desiccation of spruce plantations. The subject of our research was the spruce forests of the Russian Perm Krai's mixed forest zone. Spruce is a shade-tolerant tree species and low plantation density may adversely affect the spruce health. The aim of this research is to establish how influential the spruce stand density is on causing desiccation in mixed zones in the Perm Krai. The results of an on-site survey which had recorded spruce desiccation in 2017 were analysed. Within the boundaries of the aforementioned forest areas, 2017 saw the desiccation of spruce trees in 301 forest allotments covering an area of 5,343.7 ha. The value of the weighted average category of spruce forest health in Prikamye varies from 2.7 (severely weakened) to 4.2 (desiccating), and the percentage of the volume of spruce deadwood varies from 17% to 59.5%. When the spruce stand density rises from 0.4 to 0.8, spruce stand resilience to desiccation increases

The problem of drying up spruce stands and ways to solve it

The last decades has been witnessed of the mass spruce stands drying up problem in different countries of the world. The investigation purpose consists in establishing influence of the growth conditions and the bark beetle, on the drying up of spruce forests. Forest stands of the coniferous-broadleaved (mixed) zone forests in Russian Federation served as an object of our researcb. Based on the results of the acts of pathologic inspection, it is established that the share of drying up spruce forests decreases with increasing soil fertility and moisture. The influence of the bark beetle was investigated on the basis of materials of three sample plots in stands of the green-moss spruce type of forest. We did not find traces of vital activities of the bark beetle by the drying spruce trees with a diameter at altitudes of 1.3 m to 14 cm fully, as well as with a diameter of 14 to 22 cm partly. The fact revealed is explained by the fact that these spruce trees have a thin bark which is not enough for the beetle laying inside of it the mother gallery, and the brood bark for subsequent feeding. The bark beetle is not the primary reason of the spruce forests drying in the Permsky Kray. It is necessary to conduct a much deeper study on this problem. © 2019 Published under licence by IOP Publishing Ltd

Terminology of the aerospace industry: systemic and structural features

This article presents an attempt to describe systemic and structural features of contemporary English-language aerospace terminology. Relevance of this terminological system study is determined by rapid development of aerospace industry. Its terminology is expanding rapidly as well. Specifically, existing terms acquire new conceptual meanings; new concepts appear as well as terms to convey them; concepts and terms from adjacent domains are borrowed; general language words become specialized knowledge units within the framework of specific terminological system. The purpose of this study is to describe systemic features of aerospace terminology from the perspective of basic requirements to terms, as well as to describe structural features of terms in question. Terminological units are subject to linguistic analysis, which can be carried out in a number of ways. To conduct the research aiming at describing aerospace terminology as a system, the author used definitional, structural and statistical methods. The terminological system of the industry in question is based on «genus proximum et differentia specifica» principle. It is also marked by the presence of polysemous, homonymous, and synonymic terms. As for the structural features, there are both monolexemic and polylexemic terms: monolexemic terms cover basic, derived, and compound terms with predominance of simple terms; polylexemic terms comprise two-component, three-component, and multicomponent terms with predominance of two-component terms. Most polylexemic terms have abbreviations. Abbreviations are omnipresent in the aerospace industry terminology: on the one hand, they simplify specialized communication; on the other hand, abbreviations prevent non-specialists from understanding the aerospace discourse

Mathematical Modelling Method Application for Optimisation of Catalytic Reforming process

The application of mathematical modelling method monitoring of catalytic reforming unit of Komsomolsk oil-refinery is proposed. The mathematical model-based system “Catalyst's Control” which takes into account both the physical and chemical mechanisms of hydrocarbon mixture conversion reaction as well as the catalyst deactivation was used for catalytic reforming installation monitoring. The models created can be used for optimization and prediction of operating parameters (octane number, reactors outlet temperature and yield) of the reforming process. It is shown, that the work on the optimal activity allows increasing product output with a constant level of production costs, and get the information about Pt-Re catalyst work efficiency

Development of Complex Mathematical Model of Light Naphtha Isomerization and Rectification Processes

The technique of developing a mathematical model of catalytic isomerization of light naphtha is stated Using experimental data from an industrial isomerization unit shows adequacy of the mathematical model to the real process. The paper presents a method for optimizing the operation of the plant together with catalytic isomerization unit and separation columns. Selection of optimal modes of separation columns allows achieving the desired flow separation between units, as well as extension of the life of the catalyst SI-2

Mathematical Modelling Method Application for Optimisation of Catalytic Reforming process

The application of mathematical modelling method monitoring of catalytic reforming unit of Komsomolsk oil-refinery is proposed. The mathematical model-based system “Catalyst's Control” which takes into account both the physical and chemical mechanisms of hydrocarbon mixture conversion reaction as well as the catalyst deactivation was used for catalytic reforming installation monitoring. The models created can be used for optimization and prediction of operating parameters (octane number, reactors outlet temperature and yield) of the reforming process. It is shown, that the work on the optimal activity allows increasing product output with a constant level of production costs, and get the information about Pt-Re catalyst work efficiency

Specifics of chemical technology of fuels and high-energy substances science-based course delivered in English

Teaching science-based courses in English is relevant for modern universities involved in the internationalization processes globally. Teaching aids development becomes very actual as academic culture and methods of teaching of the target audience - international students can be different. Thus curriculum design and teaching aids development for the science-based course Chemical Technology of Fuels and High-energy Substances delivered at TPU becomes an important issue. The level of training is PhD studies within specialty 05.17.07 Chemical Technology of Fuels and High Energy Substances. The course is intended for the subsequent sessions within the academic discipline of the professional training in English. The course embraces face-to-face sessions, independent studies, tasks and tools for formative and summative assessment of graduate students` progress

Mathematical Modelling of Diesel Fuel Hydrodesulfurization Kinetics

The experimental data for hydrogenation of sulfur compounds including benzothiophenes (BT) and dibenzothiophenes (DBT) in the diesel fuel with 1.4 mass% of sulfur content is obtained using the laboratory setup with the aluminum-cobalt-molybdenum catalyst GKD-202 at the pressure of 3.5 MPa and different temperatures. The sulfur compound removal factor reaches 98 mass%. Dynamics of DBT and BT concentrations allowed designing a kinetic model represented by the system of differential equations of individual sulfur compound rates. The kinetic model was included in the developed software. The basis of the algorithm for reverse kinetic problem solution is the method of scanning through predefined range of constants. This enables performing the calculation with an error not exceeding 0.007%. The obtained data confirmed that chemical activity increases in the order: DBT, BT, sulfides. The rate of desulfurization decreases with increase in alkyl substituents concentrations. DBT desulfurization is much worse than the one of BT. The calculated data allowed building the graphs representing BT and DBT concentration dynamics

Application of Mathematical Modeling for Optimization of Linear Alkylbenzenes Sulphonation Modes in Film Reactor

The methodological aspects of development and application of mathematical modeling system for optimization of multistage petrochemical production on the example of linear alkylbenzene sulphuric acids obtaining complex processes at LLC “KINEF” were reviewed. It was shown that creation of mathematical modeling system includes a sequence of reaction network development stages, reactor kinetic modeling, model theoretical and experimental studies, studying regularities of reactor modes and proposing recommendations for raw material composition improving

Computer Modelling System Application for Catalytic Reforming Unit Work Optimisation

Catalytic reforming of naphtha is one of the most important processes for high octane gasoline manufacture and aromatic hydrocarbons production. The application of computer modelling system “Catalyst's Control” for monitoring of catalytic reforming unit of Achinsk oil-refinery is stated. The mathematical model-based system takes into account the physical and chemical mechanisms of hydrocarbon mixture conversion reaction as well as the catalyst deactivation. The models created can be used for optimization and prediction of operating parameters (octane number, reactors outlet temperature and yield) of the reforming process. It is shown, that the work on the optimal activity allows increasing product output with a constant level of production costs, and get the information about Pt-Re catalyst work efficiency