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The objective of this study is to assess the impact of low-frequency electromagnetic fields (LF EMFs) generated by power infrastructure on the nearby environment. Measurements of electric (E) and magnetic (H) field intensities were conducted around high-voltage power lines, transformer stations and facilities related to them. Numerical simulations were also performed to model the distribution of the field values around real buildings in close proximity to power delivery systems. Given the ongoing scientific debate regarding the effects of EMFs on living organisms, the current analysis was based on the existing standards—particularly ICNIRP 2010 guidelines, which set the maximum allowable E and magnetic induction (B) values at 5 kV/m and 200 μT, respectively. Stricter national regulations were also examined, such as Poland’s 1 kV/m E limit in residential areas and Belgium’s 10 μT limit for B. The results showed that while most cases complied with ICNIRP 2010 standards, certain stricter local regulations were exceeded. Specifically, 9 of 14 cases exceeded Poland’s E limits, and 8 failed to meet Belgium’s B requirements. Only in one place—a warehouse near 110 kV power lines (in a critical case)—the ICNIRP limit B was exceeded. These findings underscore the variability in regulatory standards and highlight the need for localized assessments of EMF exposure.

Zirconium-based alloys are highly regarded by the research community for their exceptional corrosion resistance, thermal stability, and mechanical properties. In our work, we investigated two newly developed alloys, Zr42.42Cu41.18Al9.35Ag7.05 and Zr46.81Cu35.44Al10.09Ag7.66, in the form of ingots and ribbons. In the course of our investigation, we conducted a comprehensive structural and thermal analysis. In addition, an examination of the corrosion activity encompassing electrochemical studies and an analysis of the corrosion mechanisms was carried out. To further evaluate the performance of the materials, tests of their mechanical properties were performed, including microhardness and resistance to abrasive wear. Structural analysis showed that both alloys studied had a multiphase, crystalline structure with intermetallic phases. The samples in the form of ribbons showed improved corrosion resistance compared to that of the ingots. The ingot containing a higher content of copper Zr42.42Cu41.18Al9.35Ag7.05 was characterized by better corrosion resistance, while showing lower average hardness and a higher degree of abrasive wear based on SEM observations after pin-on-disc tests.

Cone-beam computed tomography (CBCT) remains the diagnostic modality of choice. The involvement of the cortical bone and adjacent teeth can be easily established via CBCT. Magnetic resonance can be helpful in the estimation of any other soft-tissue tumour spread within this anatomical area. The soft, hard-tissue, or mixed aetiology of tumours requires a differential diagnosis and accurate evaluation. If such pathologies arise, an adequate biopsy or incisional biopsy is essential to evaluate the type of tumour histopathologically. The occurrence of some neural tumours in the oral cavity is rare. Schwannomas (SCs), like some neuromas and other types of neural tumours, are rare and atypical. During clinical examination, a smooth, sponge-like, elastic mass could indicate other small salivary gland tumours rather than an oral neural tumour. Such pathologies of neural origins are quite rare and are uncommon findings in the oral cavity; therefore, their appearance may be conflated with other more typical benign or malignant tumours in the oral cavity. Establishing the status of bone via CBCT, the tooth involvement and the composition of the cortical bone may be helpful for establishing the best treatment of choice. The presented case report describes a rare schwannoma localised at the mandibular retromolar trigone.

A model of α-Mg grain growth in an amorphous Mg72Zn28 alloy matrix was developed together with numerical software. Its application enables tracking the growth process of the α-Mg phase in an amorphous alloy. The model was based on the diffusion-driven growth of α-Mg in an amorphous alloy under appropriate boundary conditions at an isothermal annealing temperature and taking into account the presence of a grain with an initial radius of 1 nm. The numerical model was based on a mathematical model of heat flow, described by the Fourier–Kirchhoff equation, and diffusion, described by Fick’s second law. The initial boundary conditions necessary to simulate grain growth in the amorphous phase were established. The results of the numerical simulation indicate grain growth with increasing isothermal annealing temperature and increasing isothermal annealing time.

Contemporary clinical practice is progressively shifting towards percutaneous minimally invasive surgery. Conversely, the incorporation of transverse connectors in the design of spinal fixation systems is associated with more invasive open surgical procedures. The primary objective of this investigation was to evaluate the influence of transverse connectors in posterior spinal fixation system designs in cases involving vertebral compression fractures, specifically on selected mechanical parameters of the thoracolumbar spine in situations of instability. This research objective was achieved through a combination of experimental tests and numerical simulations. From the experimental tests conducted, critical mechanical parameters were ascertained, including the bending stiffness coefficient and energy dissipation. Numerical simulations were employed to determine additional parameters, such as the angular range of motion for individual spinal segments, intradiscal pressure within individual intervertebral discs, and stress distribution on the articular facets. Analyzing the impact of transverse connectors on the obtained results revealed that their inclusion in a fixation system results in a minor increase in stiffness and a decrease in mobility in comparison to fixation systems devoid of connectors. These findings create the potential for utilizing minimally invasive surgery as a viable alternative to open surgical procedures.

A necessary condition for agriculture to provide environmental public goods at the level desired by the society is the existence and compliance with appropriate “rules of the game” (institutions). Undoubtedly, institutions are of fundamental importance for agriculture in areas with natural or other specific constraints (ANCs), the new delimitation of which was recommended by the European Commission to all EU member states under the CAP 2014–2020 and which is valid under the CAP 2023–2027. The aim of the study is to indicate the role of institutions in the new institutional economics (NIE) approach in the context of supporting agriculture in ANCs. The specific goals consist of indicating a method for determining the current ANCs in the EU, including Poland; characterizing their current state in Poland, as compared to other EU countries; determining their role in the implementation of the agri-environment-climate (AECM) and organic farming measure under the EU CAP (they are particularly predestined to provide environmental public goods) and also specify the determinants encouraging farmers in ANCs to participate in these measures; assessing the production and economic situation of agriculture in these areas in individual EU countries. The data source was data from the Institute of Soil Science and Plant Cultivation—State Research Institute in Puławy and the Institute of Agricultural and Food Economics—National Research Institute, Agency for Restructuring and Modernization of Agriculture, European Commission FADN—FSDN. Descriptive methods were used to analyze and present the materials. Tabular graphic logistic regression model, the Wald test, the Cox–Snell pseudo-R2 measure and its additional variant proposed by Nagelkerke were used. The study is intended to fill the research gap regarding the determination of the ability of agriculture in ANCs to reconcile the market function, which is reflected in its economic situation, with the provision of environmental public goods to the society. It was determined that in communes with a high saturation of lowland ANCs, farms achieving worse production results in the form of lower wheat yields and lower net income calculated without subsidies per 1 ha of utilized agricultural area (UAA) had a greater tendency to implement AECM and organic farming measure. In most EU countries, agriculture in ANCs is characterized by extensification of agricultural production compared to other agriculture. It generally incurs lower costs and, as a result, obtains lower production effects and income from agricultural activities per 1 ha of UAA. The study provides arguments supporting the thesis that for agriculture in ANCs to achieve satisfactory economic effects and at the same time be able to provide the public with environmental public goods to a wide extent, it is necessary to have public financial incentives in the form of subsidies from the EU CAP.

W poniższej pracy przedstawiono wyniki badań dotyczące oceny jakości miodów filtrowanych pochodzących z rynku USA. Badania obejmowały analizę zawartości: wody, cukrów redukujących, sacharozy, 5-HMF, zawartości wolnych kwasów oraz poziomu przewodności elektrycznej właściwej. Uzyskane wyniki pozwoliły stwierdzić, że wartości wyróżników jakości miodów filtrowanych nie przekraczają dopuszczalnych limitów dla miodów określonych w polskich aktach prawnych. Wyjątkiem jest zawartość 5-HMF, którego wielkość znacznie przekracza dopuszczalne normy.

This study presents results of research on the quality of chokeberry herbhoneys and syrups used to produce them. The study included evaluation of the content of water, sugars, free acids and electrical conductivity. In addition, the antiradical activity against free radicals DPPH and total phenolic content were evaluated. Also color parameters L *, a *, b * were determined in the CIE system. Study results revealed that herbhoneys have met all quality requirements specified for the honey in the Regulation of the Minister of Agriculture. The processing of chokeberry syrup by bees to honey results in changes in: water content, sugars, and total polyphenol content. Herbhoney has a much higher ability of scavenge DPPH radicals, than chokeberry syrup.

The high pressure die casting (HPDC) is a technique that allows us to produce parts for various sectors of industry. It has a great application in such sectors as automotive, energy, medicine, as the HPDC allows us to produce parts very fast and very cheaply. The HPDC casting quality depends on many parameters. The parameters among others, are cast alloy alloy metallurgy, filling system design, casting technology elements geometry and orientation, as well as, machine operation settings. In the article, different plunger motion schemes of the HPDC machine were taken into account. Analyses lead to learning about plunger motion influence on the casting porosity and solidification process run. Numerical experiments were run with the use of MAGMASoft® simulation software. Experiments were performed for industrial casting of water pump for automotive. Main parameter taken into account was maximal velocity of the plunger in the second phase. The analysis covered porosity distribution, feeding time through the gate, temperature field during whole process, solidification time. Cooling curves of the casting in chosen points were also analysed. Obtained results allow us to formulate conclusions that connect plunger motion scheme, gate solidification time and the casting wall thickness on the solidification rate and porosity of the casting.

In order to investigate the effect of the milling time on the corrosion resistance of the Mg65Zn30Ca4Pr1 alloy, powders of the alloy were prepared and milled for 13, 20, and 70 hours, respectively. The samples were sintered using spark plasma sintering (SPS) technology at 350◦C and pressure of 50 MPa. The samples were subjected to potentiodynamic immersion tests in Ringer’s solution at 37◦C. The obtained values of Ecorr were –1.36, –1.35, and –1.39 V, with polarization resistance Rp = 144, 189, and 101 Ω for samples milled for 13, 20 and 70 h, respectively. The samples morphology showed cracks and pits, thus signaling pitting corrosion.

The paper presents arch structures modeled by finite elements in which the nodes can be flexibly connected. Two-node curved elements with three degrees of freedom at each node were used. Exact shape functions were adopted to obtain stiffness and consistent mass matrices but they were modified by introducing rotational flexibility in the boundary nodes. Calculations of statics and dynamics of arches with different positions of flexible joints and different values of rotational stiffness of the joints were carried out.

The paper covers some measurement aspects of transport of electrons through metals and semiconductors in magnetic field – magnetotransport – allowing for the determination of electrical parameters characteristic of three-dimensional (3D) topological insulators (TI) (i.e. those that behave like an insulator inside their volume and have a conductive layer on their surface). A characteristic feature of the 3D TI is also a lack of differences between the chemical composition of the conductive surface and the interior of the material tested and the fact that the electron states for its surface conductivity are topologically protected. In particular, the methods of generating strong magnetic fields, obtaining low temperatures, creating electrical contacts with appropriate geometry were presented, and the measurement methods were reviewed. In addition, the results of magnetotransport measurements obtained for two volumetric samples based on the HgCdTe compound grown with the molecular beam epitaxy method are presented.

The article presents the structure and a principle of operation of a simple indicator of the type of a fuel-air mixture supplying a spark-ignition engine with a direct fuel injection. The designed indicator was tested, as a result of which its correct operation was verified. By using information from the indicator, it was possible to assess its usefulness for assisting the driver in an economical driving style. Preliminary studies show that thanks to the use of the developed indicator, it is possible to save about 10% of fuel as a result of the correction of the economic driving style on the route selected for the purpose of this research paper. The target of this study was to confirm a noticeable reduction in fuel consumption when supplying the engine with a stratified mixture. In order to obtain more accurate data, the research should be extended to include a greater number of routes and its division into urban and non-urban areas.

An experimental study of the abrasive water jet cutting process of Inconel 718 alloy samples with varying values of cutting speed, abrasive flow rate and cutting material height was carried out. Surface roughness and waviness were measured at different cutting depths, and the variation of the kerf angle was studied. It was shown that the depth of cut has the greatest effect on roughness and waviness. The height of the sample has no impact on the roughness and waviness at a particular depth of cut. As the depth of cut increases, in most cases, roughness and waviness increase as well. It has been proven that the cutting speed has a negligible effect on surface roughness, but it has a significant effect on surface waviness. The waviness, on the other hand, depends only slightly on the abrasive flow. It has been proven that the kerf angle does not depend on the abrasive flow. The kerf angle depends mainly on the height of the sample. The models were developed for the parameters of roughness Ra and Rz, waviness Wa and Wz and kerf angle. All models were calculated without separating the surface into smooth and rough cutting regions.

Efforts to direct the economies of many countries towards low-carbon economies are being made in order to reduce their impact on global climate change. Within this process, replacing fossil fuels with hydrogen will play an important role in the sectors where electrification is difficult or technically and economically ineffective. Hydrogen may also play a critical role in renewable energy storage processes. Thus, the global hydrogen demand is expected to rise more than five times by 2050, while in the European Union, a seven-fold rise in this field is expected. Apart from many technical and legislative barriers, the environmental impact of hydrogen production is a key issue, especially in the case of new and developing technologies. Focusing on the various pathways of hydrogen production, the essential problem is to evaluate the related emissions through GHG accounting, considering the life cycle of a plant in order to compare the technologies effectively. Anion exchange membrane (AEM) electrolysis is one of the newest technologies in this field, with no LCA studies covering its full operation. Thus, this study is focused on a calculation of the carbon footprint and economic indicators of a green hydrogen plant on the basis of a life cycle assessment, including the concept of a solar-to-hydrogen plant with AEM electrolyzers operating under Polish climate conditions. The authors set the range of the GWP indicators as 2.73–4.34 kgCO2eq for a plant using AEM electrolysis, which confirmed the relatively low emissivity of hydrogen from solar energy, also in relation to this innovative technology. The economic profitability of the investment depends on external subsidies, because, as developing technology, the AEM electrolysis of green hydrogen from photovoltaics is still uncompetitive in terms of its cost without this type of support.

Public transport plays an increasingly important role in satisfying the transport needs. Travellers’ requirements regarding the quality of services are increasing. In addition to passenger comfort, other parameters are important (timetable and the state of transport infrastructure). Therefore, methods that determine the appropriate organization of public transport for an area should be sought. The purpose of the article is to present the most commonly used optimization methods and tools that have been applied to the chosen problems of organization of public transport mainly in Poland (described in the articles of mainly Polish scientists), but against the background of global research. The article characterizes the functioning of public transport in Poland. The selected problems of public transport functioning, which can be solved by using optimization methods and tools were discussed. The chosen methods that were used to formulate and solve the identified problems were indicated. The effects of this article will form part of the work on the POIR.01.01.01-00-0970/17-00 project "IT system for computer-aided public transport planning" financed by the National Centre for Research and Development.

Zinc oxide layers on soda-lime glass substrates were fabricated using the sol-gel method and the dip-coating technique. Zinc acetate dihydrate was applied as the precursor, while diethanolamine as the stabilizing agent. This study aimed to determine what effect has the duration of the sol aging process on the properties of fabricated ZnO films. Investigations were carried out with the sol that was aged during the period from 2 to 64 days. The sol was studied using the dynamic light scattering method to determine its distribution of molecule size. The properties of ZnO layers were studied using the following methods: scanning electron microscopy, atomic force microscopy, transmission and reflection spectroscopy in the UV-Vis range, and the goniometric method for determination of the water contact angle. Furthermore, photocatalytic properties of ZnO layers were studied by the observation and quantification of the methylene blue dye degradation in an aqueous solution under UV illumination. Our studies showed that ZnO layers have grain structure, and their physical–chemical properties depend on the duration of aging. The strongest photocatalytic activity was observed for layers produced from the sol that was aged over 30 days. These layers have also the greatest porosity (37.1%) and the largest water contact angle (68.53°). Our studies have also shown that there are two absorption bands in studied ZnO layers, and values of optical energy band gaps determined from positions of maxima in reflectance characteristics are equal to those determined using the Tauc method. Optical energy band gaps of the ZnO layer fabricated from the sol aged over 30 days are EgI = 4.485 eV and EgII = 3.300 eV for the first and second bands, respectively. This layer also showed the highest photocatalytic activity, causing the pollution to degrade 79.5% after 120 min of UV irradiation. We believe that ZnO layers presented here, thanks to their attractive photocatalytic properties, may find application in environmental protection for the degradation of organic pollutants.

As a result of the COVID-19 pandemic, the ongoing war and the implementation of the so-called Mobility Package there are profound changes taking place in the Polish LSP sector. The competitive struggle on the market is intensifying, and it mobilizes the management to diagnose the condition of companies with the use of effective comparative tools. This article aims to present the conclusions of the study of 46 entities on the Polish LSP market. It uses an original, multi-faceted evaluation method. The authors hope to popularize this method for evaluating LSPs by making it cyclical. The comparative evaluation of LSPs was carried out with the use of economic (index) and statistical analysis tools. A model of rank correlation was used for the values of all variables (ten economic parameters and one greening parameter). LSPs were grouped up based on the average value of the economic variables and according to investment attractiveness and then clustered. Sets of the most correlated characteristics in the assessment of the LSPs were developed based on the k-means method and the Spearman coefficient. A collective ranking of LSPs has been prepared.

There are many cysts and tumors which might occur in the mandibular and maxillary bones. Their origin can be either odontogenic or non-odontogenic. One of the most common odontogenic cysts is the odontogenic keratocyst (OKC). Its nomenclature and classification have changed many times over years, from a tumor to, finally, a cyst. Nowadays, its treatment has not greatly changed, however, it is related to a potential recurrence rate more than any other cyst of odontogenic origins. OKC size, localization, and possible cortical expansion towards adjacent soft tissues might influence the scope of treatment and possible reoccurrence in time. Each case is quite individual, and after removal of the pathology in some cases there can be a necessity for either bone grafting or any other reconstruction method to restore proper bone continuity. The size and the placement of OKC might influence pathological fracture occurrence or inappropriate healing if the bone cavity after cyst removal is not properly treated. A good healing potential can be achieved with xenograft bone substitutes or allograft fresh–frozen bones. On rare occasions, a titanium plate is used to ensure mandibular stability. In the following case report, an atypical case of a large OKC treated with fresh–frozen bone grafts, supported with collagen barrier material in the anterior mandible with buccal cortical expansion, will be presented.

It is well known that the magnitudes of the coefficients of the discrete Fourier transform (DFT) are invariant under certain operations on the input data. In this paper, the effects of rearranging the elements of an input data on its DFT are studied. In the one-dimensional case, the effects of permuting the elements of a finite sequence of length N on its discrete Fourier transform (DFT) coefficients are investigated. The permutations that leave the unordered collection of Fourier coefficients and their magnitudes invariant are completely characterized. Conditions under which two different permutations give the same DFT coefficient magnitudes are given. The characterizations are based on the automorphism group of the additive group ZN of integers modulo N and the group of translations of ZN. As an application of the results presented, a generalization of the theorem characterizing all permutations that commute with the discrete Fourier transform is given. Numerical examples illustrate the obtained results. Possible generalizations and open problems are discussed. In higher dimensions, results on the effects of certain geometric transformations of an input data array on its DFT are given and illustrated with an example.

The transition to a climate-neutral economy presents a particular challenge for the areas where the economy is based on rich lignite resources. One of them is the Bełchatów Basin Area in Poland. The complexity of the phenomena occurring in the area of transformation requires an interdisciplinary and integrated approach to development planning and managing. It is important to create stable conditions, allowing for the introduction of necessary changes, including the involvement of various stakeholders. The research is aimed at identifying the challenges faced by the region with a lignite-based economy, the inhibitors of the transformation process, and recommendations for public policy. During the research, secondary and primary data were analysed with the use of triangulation, which allowed to combine various techniques and sources, as well as an in-depth description and multi-faceted understanding of the case under study. The study poses a key question as to whether the public authority is capable of implementing the energy transition that would protect the global public interest. The conducted research showed deficiencies negatively affecting its implementation. There are barriers affecting cooperation in the public sphere and with other stakeholders. An analysis of the limitations in cooperation showed the dysfunction of energy policy implementation at the regional level. Vertical and horizontal actions between different stakeholders of the transformation are necessary to identify seed industries representing a transformational opportunity in the Bełchatów Basin. Renewable energy sources may play a key role in this process. Their share in electricity production should be increased. A clear and precise vision of the development of this territory, as well as a stable and diversified system of financing are important elements of change. The article draws attention to the lack of a transformation leader. Identifying an actor responsible for the protection of the global public interest is essential.

Mass customization production is a manufacturing process in which mass-produced products are modified according to specific customer needs. An example of such production is furniture production, where multiple options options for various components or features are available. Demand forecasting in mass customization industry is a difficult task for organizations and is both crucial for their profits and for market penetration. Unfortunately, the currently available tools are focused on more standard demand forecasts, which lack interpretable representation of information relevant for mass customization products. This is especially relevant for ERP systems, which are the backbone of modern manufacturing. We propose a forecasting method adapted to the needs of mass customization by focusing on demand prediction—not on finished products, but on key intermediate goods. Moreover, we provide a method for determining such goods. As an additional consequence we provide an implementation strategy that reduces the risk and time consumption when implementing forecasting in ERP systems. All the results are implemented as appropriate functionalities of a IFS Application ERP system.

The transport system has a direct impact on the economic and socio-economic situation of each country. Planning its development is an important element of policy. Bearing in mind the importance and complexity of this issue, it should be considered using both quanti-tative methods and mathematical models, as well as advanced simulation tools for modelling transport. The article presents a proposal for an approach to simulation tests of the different transport system in the aspect of the emission of harmful exhaust gas compounds from road transport.The tool for analysing and assessing the functioning of e xisting or designed systems is a model in which the properties of the real system, which are important from the point of view of the research objective, should be mapped. The Model of Proecological Transport System (MEST) was presented formally as an ordered four. Also elements of optimization taks shaping of proecological transport system in form of datas, decision variables, conditions and goal function were presented. An example of tests on simulation model was shown.

This paper presents simulation results of the interaction of TiC nanoparticle in liquid aluminum. The behavior of the TiC particle in the frontal interaction region stems from the operation of a system of such forces as gravity, viscous flow drag force, and Saffman force. The difference in density between the TiC and the aluminum matrix makes the particle fall, regardless of the radius dimension; while the Saffman force—which accounts for the local velocity gradient of the liquid aluminum—causes that particles with the smallest radii considered in the calculations 6.4 × 10−8 m; 7 × 10−8 m; 7.75 × 10−8 m; 9.85 × 10−8 m are repelled from the solidification front and the particles with 15.03 × 10−8 m are attracted to it. The viscosity growth in the course of casting caused by the lowering temperature reduces this effect, though the trend is maintained. The degree to which the particle is attracted to the front clearly depends on the velocity gradient of the liquid phase. For a very small gradient of 0.00001 m/s, the particle is at its closest position relative to the front.

Continuous work on a new generation of actuators, referred to as artificial muscles, resulted in the initiation of work on electrostatic zipping actuators, the concept of which is derived from micro electro-mechanical devices. Despite partial knowledge of their basic operating parameters, a question remains whether electrostatic zipping actuators are able to meet the expectations in the context of generated forces and control possibilities. In order to get closer to the answer to this question, the authors of this work created a solution method using FEM, which allowed them to conduct a series of concentric contraction tests of the desired solution. In addition to the basic features of the actuators tested, such as their length, thickness and width, for the first time the size of the weld surface, to which the loading force was applied, was taken into account. The results of the investigations show the possibility of adjusting the supply voltage range to the application requirements, but most importantly, they present the variability of the pull-in strain parameter. In extreme configurations, its value increases from ~10% to ~26%. The results obtained emphasize the need for further analysis of electrostatic zipping actuators using FEM. It will make it possible to precisely define the characteristics of this technology as well as its limits. These activities will provide the ultimate answer to the potential of electrostatic zipping actuators as artificial muscles.

The introduction of electromobility contributes to an increase in energy efficiency and lower air pollution. European countries have not been among the world’s leading countries in this statistic. In addition, there have been different paces in the implementation of electromobility in individual countries. The main purpose of this paper is to determine the directions of change and the degrees of concentration in electromobility in European Union (EU) countries, especially after the economic closure as a result of the COVID-19 pandemic. The specific objectives are to indicate the degree of concentration of electromobility in the EU and changes in this area, especially during the COVID-19 pandemic; to determine the dynamics of changes in the number of electric cars in individual EU countries, showing the variability in this aspect, while also taking into account the crisis caused by COVID-19; to establish the association between the number of electric cars and the parameters of the economy. All EU countries were selected for study by the use of the purposeful selection procedure, as of December 31, 2020. The analyzed period covered the years 2011–2020. It was found that in the longer term, the development of electromobility in the EU, measured by the number of electric cars, is closely related to the economic situation in this area. The crisis caused by the COVID-19 pandemic has influenced the economic situation in all EU countries, but has not slowed down the pace of introducing electromobility, and may have even accelerated it. In all EU countries, in the first year of the COVID-19 pandemic, the dynamics of introducing electric cars into use increased. The growth rate in the entire EU in 2020 was 86%, while in 2019 it was 48%. The reason was a change in social behavior related to mobility under conditions of risk of infection. COVID-19 has become a positive catalyst for change. The prospects for the development of this type of transport are very good because activities related to the development of the electromobility sector perfectly match the needs related to the reduction of pollution to the environment.

The programs WYK_Stal and Bi-Growth, developed at AGH-UST, Kraków, Poland, were used for simulating the refining process, the formation of non-metallic inclusions, and their growth. The Fe-Y-Al-O-S-Ca system in pre-oxidized steel was analyzed, where yttrium formed precipitates from both O and S. When first Al and second Y were added to steel, the proportion of Al2O3 inclusions remained constant. This resulted in higher yttrium losses for oxide formation, whereas the sulfur content promoted sulfide phase formation. The introduction of yttrium at the end of refining contributed to reducing the consumption of this element in the non-metallic phase formation. The addition of aluminum and then calcium were sufficient to achieve a high degree of deoxidation and desulfurization. Calculations performed with WYK_Stal for both (a) and (c) versions of the model showed that the sulfide phase was constituted by CaS and FeS (model c) and CaS (model (a)). The participation of the calcium sulfide phase turned out to be dominant in the inclusions. Their presence was also identified in the slag phase. Simulations of the growth of complex oxide and oxo-sulfide inclusions using the Bi_Growth program showed that the yttrium content of the steel has a decisive role in the formation of complex oxide inclusions and the final oxygen content of the steel. In contrast, for the growth of oxide-sulfide inclusions, the character of growth is determined by the sulfur content of steel.

The vision of the smart city is inextricably linked with the concepts of intelligent transport, sustainable mobility and managerial decision making. Cities of the future not only entail the use of new technology, but also increasingly the interpenetration of technological and social aspects, with the simultaneous involvement of urban space users in the creation of such technologies. This provides an opportunity to introduce desired changes and create a more balanced space with a higher quality of life and improved energy efficiency. The article discusses the concepts of sustainable development and sustainable mobility with a particular emphasis on issues related to the smart city. The authors reviewed the various smart city solutions that have been implemented in the field of urban transport in Cracow, whose authorities have taken steps over the last few years to make the city smarter and more modern. The aim of the research was to assess the contribution made by smart city solutions to improving the attractiveness and reliability of public transport in Poland’s second-largest city. The undoubted added value of this analysis is the application of the Structural Equation Modeling (SEM) method to evaluate the implemented solutions. It should be pointed out that such an analysis constitutes a new approach in this area. Until now, these models have been used to assess consumer behavior. The results showed that some of the implemented intelligent solutions increase the attractiveness of public transport in Cracow, but this does not square with users’ assessment of reliability. According to users, ecological solutions have no impact on the attractiveness of public transport. Nor do conveniences such as bus lanes, giving priority to public transport vehicles at intersections, and adjusting traffic light regulation to traffic volume, have a positive impact on perceptions of public transport as a reliable means of getting around the city. The results may be of particular importance for the city’s authorities and other stakeholders engaged in strategic activities and the building of a city of the future.

Biodegradable magnesium alloys with Zn, Yb, Ca and Sr additions are potential materials with increased corrosion resistance in physiological fluids that ensure a controlled resorption process in the human body. This article presents the influence of the use of a high cooling rate on the corrosion behavior of Mg60Zn20Yb15.7Ca2.6Sr1.7 alloy proposed for medical applications. The microstructure of the alloy in a form of high-pressure die-casted plates was presented using scanning electron microscopy in the backscattered electrons (BSEs) mode with energy-dispersive X-ray spectrometer (EDX) qualitative analysis of chemical composition. The crystallization mechanism and thermal properties were described on the basis of differential scanning calorimetry (DSC) results. The corrosion behavior of Mg60Zn20Yb15.7Ca2.6Sr1.7 alloy was analyzed by electrochemical studies with open circuit potential (EOCP) measurements and polarization tests. Moreover, light microscopy and X-ray photoelectron spectroscopy were used to characterize the corrosion products formed on the surface of studied samples. On the basis of the results, the influence of the cooling rate on the improvement in the corrosion resistance was proved. The presented studies are novel and important from the point of view of the impact of the technology of biodegradable materials on corrosion products that come into direct contact with the tissue environment.

Tissue engineering (TE) is a field of regenerative medicine that has been experiencing a special boom in recent years. Among various materials used as components of 3D scaffolds, naturally formed chitinous materials seem to be especially attractive because of their abundance, non-toxic and eco-friendly character. In this study, chitinous skeleton isolated from the marine sponge Aplysina fistularis (phylum: Porifera) was used for the first time as a support for the cultivation of murine fibroblasts (Balb/3T3), human dermal fibroblasts (NHDF), human keratinocyte (HaCaT), and human neuronal (SH-SY5Y) cells. Characterization techniques such as ATR FTIR, TGA, and μCT, clearly indicate that an interconnected macro-porous, thermostable, pure α-chitin scaffold was obtained after alkali–acid treatment of air-dried marine sponge. The biocompatibility of the naturally formed chitin scaffolds was confirmed by cell attachment and proliferation determined by various microscopic methods (e.g., SEM, TEM, digital microscopy) and specific staining. Our observations show that fibroblasts and keratinocytes form clusters on scaffolds that resemble a skin structure, including the occurrence of desmosomes in keratinocyte cells. The results obtained here suggest that the chitinous scaffold from the marine sponge A. fistularis is a promising biomaterial for future research about tissues regeneration.

This paper presents a comprehensive methodology for measuring and characterizing the surface topographies on machined steel parts produced by precision machining operations. The performed case studies concern a wide spectrum of topographic features of surfaces with different geometrical structures but the same values of the arithmetic mean height Sa. The tested machining operations included hard turning operations performed with CBN tools, grinding operations with Al2O3 ceramic and CBN wheels and superfinish using ceramic stones. As a result, several characteristic surface textures with the Sa roughness parameter value of about 0.2 μm were thoroughly characterized and compared regarding their potential functional capabilities. Apart from the standard 2D and 3D roughness parameters, the fractal, motif and frequency parameters were taken in the consideration.

The correct operation of the continuous welded track requires diagnosing its condition and preparation of track metrics requiring measurements of displacements of rail under operation. This is required as there are additional thermal stresses in the rails with values depending on the temperature changes of the rails. Therefore, the climatic conditions are important. This paper presents the original effective analytical method for diagnosing the condition of continuous welded track based on experimental research. The method allows for an appropriate repair or maintenance recommendation. In the experimental research, the authors considered track diagnostic conditions for two conditions: track under load and track without load. This paper presents empirical formulas for calculating rail temperature and longitudinal force based on ambient temperature, developed from long-term measurements. The formulas were developed for a track located on a straight section—both for a rail loaded and unloaded with a passing train under the following conditions: 60E1 rail, not on an engineering structure, conventional surface, wooden sleepers and very high train traffic load. The obtained results in the value of the correlation coefficient R2 ≥ 0.995 attest to very high accuracy of the calculations performed with the method proposed by the authors.

High feed Milling is a new milling method, which allows to apply high feed rates and increase machining efficiency. The method utilizes face cutters with a very small entering angle, of about 10°–20°. Thus, the cut layer cross-section is different than in traditional milling. In order to examine the high feed milling (HFM), experimental tests were conducted, preceded by an analysis of cutting zones when milling with an HF face cutter. The face milling tests of 42CrMo4 steel with the use of an HF cutter characterized by an entering angle, dependent on axial depth of cut ap and insert radius r values, as well as with a conventional face cutter with the entering angle of 45° were performed. The study focused on analyzing the vibration amplitude, cutting force components in the workpiece coordinate system, and surface roughness. The experimental tests proved, that when milling with constant cut layer thickness, the high feed cutter allowed to obtain twice the cutting volume in comparison with the conventional face cutter. However, higher machining efficiency resulted in an increase in cutting force components. Furthermore, the results indicate significantly higher surface roughness and higher vibration amplitudes when milling with the HF cutter.

An increasing percentage of ethanol in fuel leads to significant changes in polarity and solubility, which makes conventional gasoline deposit control additives (DCAs) difficult to dissolve in ethanol fuels, resulting in the formation of deposits on engine elements. Critical areas of deposit formation in an engine are constituted by inlet valves, combustion chambers, and fuel injectors. As a consequence, operational parameters of the engine are disturbed to a large extent by the total effect of the deposits. To prevent the aforementioned phenomena, in the operation of engines fueled with ethanol-containing blends, it is necessary to use specifically prepared DCAs. The paper briefly presents a process of development of DCAs dedicated to high-ethanol fuels. Each of the prepared DCA formulations contained a substance having detergent-emulsifying properties (referred to in the text as DEM), a carrier oil, and a solvent. The composition and ratios of components used in the DCA, by testing their effectiveness in engine deposit formation, are verified. A motor station and a test procedure developed for this purpose were used. In search of alternative solutions to conventional polyisobutyleneamines (PIBA) and polyetheramines (PEA) surfactants, which have good solubility in hydrocarbons but not in ethanol, a substance with a benzoxazine structure and a Mannich base were synthesized. Their chemical structures were confirmed by nuclear magnetic resonance (NMR) DCAs were developed, and the effectiveness of their action was verified. Moreover, attention was paid to the dosage level of the DEM and the carrier oil in the DCA. Finally, it was confirmed in the studies carried out that DCAs used for improvement of conventional hydrocarbon engine gasolines are not efficient enough when used in E85 fuels. In the case of the latter, DCAs that have been specifically developed for such fuels should be used, because they have a different chemical structure, and are soluble in the ethanol-gasoline mixture in any ratio of both components.

Herein, a facile and efficient synthetic route to unique hybrid materials containing polysiloxanes and mono(alkyl)silsesquioxanes as their pendant modifiers (T8@PS) was demonstrated. The idea of this work was to apply the hydrosilylation reaction as a tool for the efficient and selective attachment of mono(alkenyl)substituted silsesquioxanes (differing in the alkenyl chain length, from -vinyl to -dec-9-enyl and types of inert groups iBu, Ph at the inorganic core) onto two polysiloxanes containing various amount of Si-H units. The synthetic protocol, determined and confirmed by FT-IR in situ and NMR analyses, was optimized to ensure complete Si-H consumption along with the avoidance of side-products. A series of 20 new compounds with high yields and complete β-addition selectivity was obtained and characterized by spectroscopic methods.

Bifunctional silsesquioxanes create an attractive group of compounds with a wide range of potential applications, and recently they have gained much interest. They are known to be obtained mainly via hydrosilylation, but we disclose novel synthetic protocols based on different but complementary reactions, i.e., cross-metathesis (CM) and silylative coupling (SC). A series of cubic T8 type silsesquioxane derivatives with a broad scope of styryl substituents were synthesized in a one-pot procedure and characterized by spectroscopic and spectrometric methods. All of the new compounds can be obtained in a one-pot manner, which has an attractive impact on the synthetic procedure, as it is economic in terms of the isolation of intermediate products. Additionally, the methodology disclosed here enables the (E)-stereoselective introduction of styrenes derivative to the cubic T8 type core. The presented compounds can be interesting precursors for a further functionalization that may significantly increase the possibility of their application in the design and synthesis of new functional materials.

The numerical modelling of structural elements is an important aspect of modern diagnostic systems. However, the process of numerical implementation requires advanced levels of consideration of multiple aspects. Important issues of that process are the positive and negative aspects of the methods applied. Therefore the aim of this article is to familiarise the reader with the most important aspects related to the process of numerical modelling of one-dimensional problems related to the phenomena of the propagation of elastic waves and their application for damage detection purposes.

This article presents state-of-the-art welding methods and the weldability aspect of steels, particularly high-carbon nanobainitic (NB) steels, without carbide precipitates (CFB—carbide-free bainite). On the basis of research conducted to date, all welding methods with parameters and weld metals for NB CFB are presented. It was found that the process parameters significantly affected the mechanical properties of the welds, which were determined primarily by the properties of the low-temperature heat-affected zone. The microstructures of welded joints in the heat-affected and fusion zones are also described. The general requirements for welding processes, as well as problems and perspectives for further research, are presented.