The paper aims to present the author's views on the general characteristics and ecological aspects of the development of polymer engineering materials and the concept of strategic prevention of environmental degradation that threatens it.Avoiding a global environmental catastrophe requires immediate and complete elimination of the production of non-recyclable polymer materials, a significant increase in the production of biodegradable bio-based materials that enable, among others, the expansion of composting as a method of polymer waste disposal, and the enforcement of well-organised and 100% recycling of products made from polymer materials.The concept of complete limiting the production of non-recyclable polymer materials and significantly intensifying the recycling of polymer materials is closely related to the rationing of primary production of polymer materials only to recyclable grades. It is the only way to prevent further pollution of the natural environment by non-removable polymer waste. The waste, over time, is processed into micro-waste in a way that is not recycled. Uncontrollably polluting the Earth's atmosphere in all regions of the world without exception, thus posing an inevitable threat to living organisms and, above all, to humans.A consistent approach to such principles is the only chance to avoid a global environmental disaster threatened by the continuation of the hitherto careless approach to the serious global problem.The paper contains a collection of source data indicating the global environmental threat due to the uncontrolled development of the production of polymer materials, which significantly threatens civilisation, so the concept of totally eliminating the production of non-recyclable polymer materials and significantly intensifying the recycling of polymer materials is presented.

Analysis of the issue of manufacturability of the material on selected examples in the context of various stages of product production.The material technology issue was analysed based on selected examples of product manufacturing technologies available in the literature.As a result of the review of selected technological processes, essential aspects of the manufacturability of the material were identified, which should be considered at all stages of product design and manufacturing.The article is an introduction to a more detailed analysis of the aspects of the manufacturability of material and its connections with other issues, as well as the stages of product manufacturing.The article is an authorial view on the approach to a very important issue, that is, manufacturability of material. It points to the interdisciplinary nature of this issue.

Helmets are included in the group of personal protective equipment and are used when other hazard control methods are insufficient. They protect against head injuries caused by various environmental factors, e.g. mechanical and thermal loads, as well as flames. Injuries due to falling debris are serious and may be fatal. Taking that into consideration, the basic role of helmets is to absorb impact energy and dissipate it over a greater surface to decrease forces acting on the head. The following work aims to study the influence of maintenance on the energy absorption capacity of firefighters’ helmets.The research was conducted on two helmet models that differ in design, both new ones and maintained for 4 years. Shells of one group of helmets were manufactured using an injection moulding method, while shells of the second group were made as a laminate. Tests were carried out using a drop hammer with the impact energy at the level of 30 J.Maintenance had a significant influence on the energy absorption mechanism. An increase in fragility and decrease in stiffness of a shell was observed, which reduces the protective properties of helmets. It constitutes a real hazard for firefighters.The research results refer to specific helmet models. The influence of the maintenance on the protective properties of other models of helmets may be different.The research results indicate that a visual assessment of firefighters’ helmets’ technical condition is insufficient. The durability of helmets should also be determined by the time of use.The paper contains original research results. According to the author’s knowledge, the results of the influence of maintenance on the protective properties of firefighters’ helmets have not been presented in any scientific publication.

The work aims to develop an information and software system for the operational analysis of geophysical well-logging (GWL) data from underground gas storage (UGS) facilities for any period of their operation. In order to increase the efficiency of the detailed analysis of the well-logging data accumulated over the entire period of operation of gas storage facilities, it is advisable to store them in electronic form.Information and software systems have been developed to allow geological and geophysical information accumulation, verification, correction and analysis. Data from the developed databases are used to automate the process of creating graphical geological materials for each well and for UGS facilities.The purpose of the systems is to provide automated solutions to various geological and technological tasks using personal computers by means of timely processing, systematisation, accumulation of initial information, and graphical and documented display of the information.Information and software systems have been developed to display the results of lithological analysis of UGS borehole sections and to correlate UGS borehole sections.The application of the developed software in production can increase the efficiency of analysis of geological and geophysical information on wells and production horizons, identify possible complications and take timely measures.To solve possible complications in gas storage wells in time, it is necessary to analyse the results of geophysical surveys to predict them.Implementation of the developed information and software system will increase the efficiency of the analysis of geophysical information in order to provide timely solutions to various problems.The application of the developed information and software system will allow for the timely analysis of geological and geophysical information to solve problematic issues.

The primary aim of this research was to develop a mathematical and computational model of the nitriding process for steel using CA cellular automata theory, which enables the modelling of spatial hardness distributions and nitrogen concentrations within the material.The proposed mathematical model consists of two interacting cellular automata: one representing the surface layer of the nitride material and the other describing the spatial distribution of nitrogen. The developed algorithm and model based on CA were implemented in the MATLAB environment, enabling more effective and efficient testing of the created model and its further use.The developed computer model enabled, by changing the values of the CA model parameters, which correspond to the nitrogen diffusion coefficient in alloy steel, nitrogen solubility in iron and the enthalpy of formation and decomposition of iron nitrides, to adapt the model to the description of the nitriding process of 1.2343 (WCL) steel. The model was experimentally verified by comparing predicted hardness profiles with those measured after nitriding.The main limitation of the developed model is the size of the material fragment in which the nitriding process is simulated.High compliance of the results of numerical calculations with the results obtained by experimental measurements was obtained, which predestines the potential usage of CA-based models for scientific and practical applications. The model can be used as part of an optimisation procedure for designing hybrid composite layers for tribological applications, comprising a nitride layer and a coating deposited via Physical Vapor Deposition (PVD) techniques.The added value of the developed model of the nitriding process, based on the concept of CA, is the author’s modification of the transition rules (both for cells in the Moore and von Neumann neighbourhood) in the automaton related to the structural and phase transformations in the nitride material.

The conducted research aims to describe the kinetics of Streptococcus mutans bacteria growth on the surface of Zr-C coatings with varying carbon content deposited on 316L medical-grade stainless steel substrates.The coatings were deposited using the MS PVD (Magnetron Sputtering Physical Vapour Deposition) technique at a constant temperature of 400C. Varying carbon contents in the coatings were achieved by changing the flow rate of acetylene during the process. The dynamics of bacteria growth cultivated at 37C were examined on the surface of the coatings for incubation times ranging from 0 to 72 hours. Generalised logistic functions were utilised for the mathematical description of the obtained results.The produced coatings exhibited varying carbon content, determining the structural composition ranging from a mixture of metallic Zr and ZrC through stoichiometric zirconium carbide to nanocrystalline grains of ZrC in an amorphous carbon matrix. The obtained results unequivocally demonstrate that in the case of ZrC coatings, the carbon content influences both the bacterial growth rate during the proliferation phase and the final population of bacteria.In the conducted research on bacterial population dynamics, only a single strain of Streptococcus mutans was considered, and the mathematical description was limited to reaching a pseudo-steady state by the population.The proposed model can successfully be adapted to describe the dynamics of other individual strains of bacteria dwelling on metallic surfaces as well as coatings.The proposed model can serve as a tool for studying, among other things, inflexion points of logistic curves, which are considered as the boundary between the dominance of anabolic and catabolic processes in the bacterial population.

The research aims to evaluate the nano-additives for oil, decreasing friction, surface roughness, and decreasing wear.Wear and friction coefficient are examined using a pin on a disk device; adding 2 wt.% nano-additives to the blended lubricant resulted in maximum friction and wear.In the current research, one of the more significant findings to emerge from this study is that the nano-additives increase viscosity and reduce wear and friction coefficient. The highest viscosity values were when adding GNP, and improving the percentage of nano-additives leads to an increase in viscosity.The results reveal that the additive was chosen as the most appropriate concentration in the blended lubricant.An experimental investigation was conducted to explore the effects of nano-additive graphene nano-powder (GNPs), molybdenum disulfide (MoS2), and titanium oxides (Tio2) in concentrations (0.5%,1%, 1.5%, 2%,2.5% ) as additives to engine oil (Al-Rashid oil) SAE 15W_40 and 5% palm oil.The results presented in the given paper may facilitate improvements in the nano-additives, resulting in increased viscosity compared to the base oil.