Along with the increase in popularity of the sewage sludge thermal treatment methods in Poland

resulting from the implementation of European Union law, a management problem with ash, which is produced

as a result of this process, appeared. The paper analyses the chemical composition and physical properties of fl y

ash from thermal treatment of municipal sewage sludge in terms of its use in concrete technologies in relation to

EN 450-1 Fly ash for concrete. Defi nition, specifi cations and conformity criteria (2012) and EN 197-1 Cement.

Composition, specifi cations and conformity criteria for common cements (2011) standards. The tested material did

not meet the requirements related to use of fl y ash for concrete production (chemical composition, low activity

index, high water demand and fi neness), and as main and minor components for cement production. On the basis

of the carried out research and analyses, it was found that the hardening slurry technology creates the greatest

possibilities related to the management of fl y ash from thermal treatment of municipal sewage sludge.

Speciation of trace elements in the sediment of a meromictic Piaseczno Lake (inundated opencast sulphur mine, southern Poland) with permanently anoxic monimolimnion was studied. A 6-step sequential extraction procedure was applied to determine operationally defined phases: exchangeable (FI), carbonate (F2). easily reducible (F3), moderately reducible (F4), organic/sulphides (FS). and residual (F6) in the sediment. The differences in trace elements (except Mn) speciation in the littoral sediment with the respect of lake depths were not found Considerable difference in the trace elements speciation between the littoral sediment and permanently anoxic profundal one was found.

Various studies have indicated that children’s preferences are biased towards those who have more resources or who are considered more fortunate than others. Little is known, however, about whether this preference translates to a moral assessment of the character of those with more or less resources. Our study included 46 children aged four to five. We asked participants to indicate their preference for the richer and the poorer in desirable resources. We also asked them to attribute the moral character of the moral agent or moral recipient. The children revealed a strong bias towards the advantaged character. Not only did they prefer him as a future friend, they also attributed morally positive social roles to him.

Climate change, manifested by long term periods of drought to heavy rainfall, may remarkably modify river flow regimes. We hypothesize that flow prevailing in a given year determines water chemistry of the Carpathian Raba River above and below Dobczyce Reservoir (southern Poland), used for drinking purposes. Based on the mean annual river flow for years 1991‒2017, hydrologically dry (HD), hydrologically average (HA)and hydrologically wet (HW) years were distinguished. We found significant differences in the values of most studied physicochemical parameters of river water above and below the reservoir between studied hydrological years (for a period of April‒November). In HD years, the water above the dam had significantly higher temperature and values of conductivity (point pollution source, groundwater inflow), while lower ones of nutrients NO3- and P-tot (diffuse pollution) compared to those in HA and/or HW years. The best GLM models for mean monthly flows above and below the dam include 3‒5 factors among which conductivity and NO3- concentration were always present. The reservoir in different ways influences the water chemistry below the dam in HD, HA and HWyears. The impact of flow on the water quality in hydrologically varied years is discussed. The obtained results are important for appropriate management in catchment basins of mountain rivers and the protection of dam reservoirs against the eutrophication processes in changing climate and flow regime.

An increasing number of municipal sewage treatment plants in Poland, desirable from an environmental perspective, raises the problem of managing the growing volume of sewage sludge. The thermal treatment of municipal sewage sludge (TTMSS) method, by greatly reducing the waste volume, increases the heavy metal concentration in fly ash (primary, end product of the treatment process), which may constitute a risk factor when attempting to utilize them economically. The research paper concentrates on determining the TTMSS fly ash heavy metal leaching level. For this purpose, ash samples were subjected to leaching with the batch and percolation tests, and the heavy metal content in eluates was determined by the FAAS method. The obtained results served as a base to determine the level of heavy metal immobilization in the ash, the element release mechanism (percolation test), and the impact of the L/S (liquid to solid) ratio and pH on the heavy metal leaching intensity (percolation test). The conducted research indicated high immobilization of heavy metals in TTMSS fly ash, regardless of the applied study method, which corresponds to the results of other researchers. Lead was the most intensively eluted metal.

Physicochemical parameters of water and phytoplankton composition were studied in the dirnictic, submountain Dobczyce Reservoir (southern Poland) affected by summer storrnflow, which took place in September 2007. During summer (except September) temperature, pH, dissolved oxygen, and carbonates showed vertical differentiation. Stormwater flow through the system had a destabilizing effect on summer stratification. It diluted the concentrations of salts (sulphate and chloride) and slightly increased the concentration of nutrients in the reservoir. In phytoplankton some changes in the dominant species among the Cyanobacteria group were noted.

In recent years, there has been a marked increase in the amount of municipal waste generated in Poland. In 2020, 21.6% of all municipal waste was subjected to a thermal treatment process. Consequently, the amount of ashes generated is significant. Due to their properties, it is difficult to utilize this type of waste within concrete production technology. One of the waste utilization methods is to add it to hardening slurries used in, among others, cut-off walls. The article assesses the possibility of using ashes from municipal waste incineration as an additive to hardening slurries. It also discusses the technological properties of hardening slurries with the addition of the ashes in question. The experiment showed that it is possible to compose a hardening slurry based on tested ashes with technological properties suitable for use as a cut-off wall. Further research directions were proposed.

Missing data in test result tables can significantly impact the analysis quality, especially in relation to technical sciences, where the mechanism generating missing data is often non-random, and their presence depends on the non-observed part of studied variables. In such cases, the application of an inappropriate method for dealing with missing data will lead to bias in the estimated distribution parameters.
The article presents a relatively simple method to implement in dealing with missing data generated as a result of the MNAR mechanism, which utilizes the censored random variable. This procedure does not modify the variable distribution form, which is why it ensures objective and efficient estimation of distribution parameters within studies affected by certain restrictions of technical or physical nature (censored distribution), with a relatively low workload. Furthermore, it does not require the application of specialized software. A prerequisite for using this method is the knowledge of the frequency and cause of missing data.
The method for estimating the random variable censored distribution parameters was shown based on the example of studying the leachability of selected heavy metals from a hardening slurry. The analysis results were compared with classical methods for dealing with missing data, such as, ignoring missing data observations (listwise or pairwise deletion), single imputation and stochastic regressive imputation.

The growing number of municipal sewage treatment plants in Poland raises the problem of managing more and more sludge. The thermal treatment of municipal sewage sludge (TTMSS), which significantly reduces the volume of waste, results in an increase in the concentration of heavy metals in the fly ashes – the final products of the process. The search for methods of utilization of fly ash from TTMSS resulted in attempts to use it in hardening slurries widely used in hydro-engineering. Due to the nature of the application of this material in the cut-off walls (exposure to groundwater flow) one of the key issues is the degree of heavy metal immobilization. The paper attempted to determine the degree of leaching of selected heavy metals from the hardened hardening slurry, composed of fly ash from TTMSS. For this purpose, the eluates were prepared from samples, after various periods of curing, using a dynamic short-term method called "Batch test". The liquid used for leaching was: distilled water and 0.1 molar EDTA solution – to determine the amount of potentially mobile heavy metal forms. The results show the possibility of the safe usage of fly ash from TTMSS as an additive for hardening slurries.

Antarctica is perceived as one of the most pristine environments on Earth, though increasing human activities and global climate change raise concerns about preserving the continent’s environmental quality. Limited in distribution, soils are particularly vulnerable to disturbances and pollution, yet lack of baseline studies limits our abilities to recognize and monitor adverse effects of environmental change. To improve the understanding of natural geochemical variability of soils, a survey was conducted in the fellfield environments of Edmonson Point (Victoria Land). Soil samples were analyzed for six major (Fe, Ca, Mg, Na, K and Ti) and 24 trace elements (As, Ba, Be, Bi, Cd, Co, Cr, Cs, Cu, Ga, Li, Mn, Mo, Ni, Pb, Rb, Sn, Sr, Tl, U, V, Y, Zn and Zr). Relationships among element concentrations in the samples and local bedrock were analyzed to identify their origin and similarities in geochemical cycles. Element concentrations in the soils were highly variable but generally within the lowest values reported elsewhere in Antarctica. Though values of Cd, Mn, Ni and Zn were relatively high, they are consistent with those in the local soil-forming rocks indicating an origin from natural sources rather than anthropogenic contamination. Chemical composition of soils vs. rocks pointed to alkali basalts as the lithogenic source of the soil matrix, but also indicated considerable alteration of elemental composition in the soil. Considering local environmental settings, the soil elemental content was likely affected by marine-derived inputs and very active hydrological processes which enhanced leaching and removal of mobilized elements. Both of these processes may be of particular importance within the context of global climate change as the predicted increases in temperature, water availability and length of the summer season would favor mineral weathering and increase geochemical mobility of elements.

The article presents the results of research on selected thermal, mechanical properties, as well as the microscopic structure of filaments and details made on a 3D printer in FDM technology. The materials used in the study were PETG (polyethylene terephthalate doped with glycol) and PLA (polylactide) doped with copper. As part of the study, Differential Scanning Calorimetry (DSC) was performed in order to determine the temperatures of phase transformations and changes in melting enthalpy values of filaments before the printing process and also elements made of them. The second part of the research was electrocorrosive ageing process of printouts, carried out in the Simulated Body Fluid solution in a device generating 0.3 A direct current, voltage with value 4.3 V for the entire duration of the test, which was 720 h. After this process DSC test was conducted again. The next stage of the research was Dynamic Mechanical Analysis (DMA) of printouts before and after electrocorrosive ageing process. This test was carried out to characterize the dynamic-mechanical properties as a function of frequency, temperature and time. Additionally, microscopic analyses of the surfaces of the tested printouts were performed in order to assess the changes after electrolysis.

The article has been devoted to issues connected with the alloplasty and hip joint endoprostheses, that elements are being developed, which is supported by strength, tribological tests on used biomaterials, incl. polyethylene or computer modelling based on e.g. finite element method (FEM). In this paper, the results of research on the impact of the material articulations of the system head – acetabular and friction conditions on strength parameters of polyethylene components in the hip joint endoprosthesis. Numerical analysis of this friction node was carried out, using the ADINA System computer program and the simulations were performed at various friction conditions for metal/ polyethylene and ceramic/ polyethylene articulations with various UHMWPE modifications. The simulations results have shown the influence of tested material associations and friction conditions on parameters related to the strength of polyethylene cups, i.e. their displacements, stresses and deformations.

The article has presented the method of 3D Digital Light Processing printing as one of the technologies used for rapid prototyping of dental models and making elements of dentures. In this work the research was presented, which the aim was to determine the effect of additional exposure time on the properties of the obtained printouts. Dynamic Mechanical Analysis test showed significant differences in stiffness between uncured specimens as well as specimens cured for 10, 20 and 30 minutes. In turn the obtained TG and DTG curves allowed to determine the most optimal curing time for DLP printouts. These studies provide the basis for determining the most appropriate method for handling printouts after the process of printing from liquid resin, so that they are the best possible quality for dentists and prosthodontists.

Lipogranulomas are lesions found in histopathological liver examination in humans and in various animal species, including dogs, especially those with portosystemic shunts. They consist of macrophages and other inflammatory cells, and sometimes they contain iron salts (pigment granuloma). This study aimed at determining the number of granulomas and cellular composition of lipogranulomas in dogs with the congenital extrahepatic portosystemic shunt, and to identify factors associated with their development. 44 archival liver samples from dogs with portosystemic shunt were stained using HE, Perl’s method and – in randomly-selected cases – immunohistochemically against CD56, CD20 and CD3 (DAKO). A reduction in the size of the liver was observed in all dogs during laparotomy, and the diameter of the vessel circumventing the liver was also measured (in 24 dogs). Lipogranulomas were found in 52.3% of samples; iron salts were present in 47.8% of them; 72% of cells in lipogranulomas were macrophages. In lipogranulomas both types of lymphocytes – T and B – were seen. The presence of lipogranulomas in liver samples in dogs was connected with fatty degeneration of hepatocytes and was correlated with the age of animals and with the diameter of the abnormal vessel circumventing the liver. Their formation appears to be triggered by severe ischemia and shortage of nutrient supply.

Cut-off walls built using self-hardening slurries are an important tool for modern engineering pursuing Sustainable Development Goals. Much like cement concrete, this material is affected by the challenges posed by the increasing human pressure on the environment, although it is used significantly less widely than concrete; for this reason, relatively little comprehensive literature data is available describing the interaction of self-hardening slurries with the environment. This article provides a review that complements the current state of knowledge on self-hardening slurries in this area, with a particular focus on the durability of the material and its pollutant immobilization capabilities. To provide context, the material’s operating conditions, properties and components are briefly characterized. The resistance of self-hardening slurries to environmental aggression is described extensively, as it is a key factor in ensuring the durability of the material. A sample analysis of the material’s carbon footprint in several representative composition variants is presented. The subject of pollutant immobilization by self-hardening slurries is outlined. Lines of further research are proposed to fill gaps in the available knowledge.