Increasing energy security in the face of rising energy demand and declining funding for fossil fuels has necessitated the diversification of energy supply and the shift to renewable energy. Sustainable management of energy supply is aimed at achieving a low-carbon intensity of production, especially in energy-intensive industries, including the mechanical-engineering industry. The article examines the possibility of shifting the current mechanical-engineering enterprise system and the technical, environmental and economic indicators of production to the new concept of the green economy, which will be an alternative to the further sustainable development of the industry. This article analyzes key approaches to energy conservation. An analytical model has been developed for calculating the energy risk of the mechanical-engineering enterprise and has built a context diagram of mechanical-engineering production, taking into account the environmental impact and the possibility of energy modernization, which allows the setting of strategic goals to ensure the sustainability of energy supply in the mechanical-engineering industry and develop the main principles of efficient enterprise activities in the context of increased risk. It has been proven that one of the criteria for increasing the profitability indicator is the adaptability of enterprises to external conditions and increasing alternative options for obtaining energy from our own autonomous sources.

The paper is focused on use of renewable energy sources for energy production with special attention paid to the biomass wastes. Type and potential of wastes biomass, which can be used for production of electric and thermal energy, were generally characterized, use of the biomass as energy source in Poland was discussed, existing reserves were estimated and basic strategic-and-legal acts, which refer to the considered problem were presented. A type of possible activities to increase the amount of alternative energy produced in Poland, in the light of requirement to achieve a determined ecological-and-energy target resulting from international agreements and EU legislation, were indicated.

RC flat slabs are one of the most popular and effective methods of shaping plates in buildings. Although failures of entire structures are relatively rare, they cannot be excluded from the occupancy cycle of the facility. The research analysis presented in this paper is an attempt to understand more precisely the phenomena that occur in the RC flat slab system and to assess the influence of the additional protection of the flat slabs against progressive collapse in the case of failure of one of the supports. The results were obtained from destructive experimental investigations of a flat reinforced concrete slab made in scale 1:3. The collapse in the analysed model was simulated by removing three edge columns and additional loading by means of hydraulic actuator. In place of the columns removed, differential tie reinforcement was applied. The results obtained confirm that the structure achieved a much higher ultimate load than the one resulting from the design calculations.

The paper examines from the thermodynamic point of view operation of coal fired power unit cooperating with the cryogenic oxygen unit, with a particular emphasis on the characteristic performance parameters of the oxygen unit. The relatively high purity technical oxygen produced in the oxygen unit is then used as the oxidant in the fluidized bed boiler of the modern coal fired power unit with electric power output of approximately 460 MW. The analyzed oxygen unit has a classical two-column structure with an expansion turbine (turboexpander), which allows the use of relatively low pressure initially compressed air. Multivariant calculations were performed, the main result being the loss of power and efficiency of the unit due to the need to ensure adequate driving power to the compressor system of the oxygen generating plant.

The paper is devoted to the problems of exergetic cost determination. A brief description of theoretical fundamentals of exergetic cost determination and its application are presented. The applied method of calculations is based on the rules of determination of cumulative exergy consumption. The additional possibilities ensured by the exergetic cost analysis in comparison to the direct exergy consumption analysis are discussed. The presented methodology was applied for the analysis of influence of operational parameters on exergetic cost indices of steam power plant. Results of calculations concern one of the modern Polish power plant unit. Basing on the obtained results several conclusions have been formulated that show advantages of application of exergetic cost analyses.

This article presents a concise overview of the achievements of synchronic research in the field Slavic linguistics carried out in Poland. Due to an enormous range of research topics, the author had to narrow her attention to selected grammatical phenomena, namely morphology (excluding word formation) and syntax, as well as to limit the scope of the analysis to books and monographs, to the exclusion of publications of a different nature.

On the basis of selected subfields in linguistics, the author describes some general trends and tendencies concerning both the choice of a theoretical framework as well as the subject matter. She distinguishes among three periods for which she seeks to determine the dominant features.

The analysis shows that during the last 60 years, and especially since the 1970s, Slavic linguistics has seen a steady growth and a search for new solutions in the field of grammar research. The growth is accompanied by an ever-increasing potential for contact with the trends occurring in global linguistics. However, one should not underestimate the achievements of Polish theoretical linguists, slavicists and specialists in Polish Studies, whose research findings encompass a detailed description of a wide range of linguistic issues and cover considerable language data.

Heating of steel or structural aluminum alloys at a speed of 2 to 50 K/min – characterizing the fire conditions – leads to a reduction in mechanical properties of the analyzed alloys. The limit of proportionality fp, real fy and proof f₀₂ yield limit, breaking strength fu and longitudinal limit of elasticity E decrease as the temperature increases. Quantitative evaluation of the thermal conversion in strengths of structural alloys is published in Eurocodes 3 and 9, in the form of dimensionless graphs depicting reduction coefficients and selected (tabulated) discrete values of mechanical properties. The author’s proposal for an analytical formulation of code curves describing thermal reduction of elasticity modulus and strengths of structural alloys recommended for an application in building structures is presented in this paper.

We assessed culturable soil microfungal diversity in various habitats around Hornsund, Spitsbergen in the High Arctic, using potato dextrose agar ( PDA) medium. Thermal growth classification of the fungi obtained was determined by incubating them in 4 ° Cand 25 ° C, permitting separation of those with psychrophilic, psychrotolerant and mesophilic characteristics. In total, 68 fungal isolates were obtained from 12 soil samples, and grouped into 38 mycelial morphotypes. Intergenic spacer regions of these morphotypes were sequenced, and they represented 25 distinct taxonomic units, of which 21 showed sufficient similarity with available sequence data in NCBI to be identified to species level. Soil under ornithogenic influence showed the highest species diversity, including sequences assigned to Mortierella macrocystis, M. elongata, Mortierella sp., Cudoniella sp., Varicosporium elodeae , Beauveria bassiana , Geomyces pannorum , Penicillium sp. and Atradidymella muscivora . Fourteen taxa were classified as psychrophilic, seven mesophilic, and four psychrotolerant.