This study presents the results of concentrations of rare earth elements and yttrium (REY ), uranium (U), and thorium (Th) in ashes from combustion/co-combustion of biomass (20%, 40%, and 60% share) from the agri-food industry (pomace from apples, walnut shells, and sunflower husks) and hard coal. The study primarily focuses on ashes from the co-combustion of biomass and hard coal, in terms of their potential use for the recovery of rare earth elements (REE ), and the identification of the sources of these elements in the ashes. Research methods such as ICP-MS (inductively coupled plasma mass spectrometry), XRD (X-ray diffraction), and SEM -EDS (scanning electron microscopy with quantitative X-ray microanalysis) were used. The total average content of REY in ash from biomass combustion is 3.55–120.5 mg/kg, and in ash from co-combustion, it is from 187.3 to 73.5 mg/kg. The concentration of critical REE in biomass combustion ash is in the range 1.0–38.7 mg/kg, and in cocombustion ash it is 23.3–60.7 mg/kg. In hard-coal ash, the average concentration of REY and critical REY was determined at the level of 175 and 45.3 mg/kg, respectively. In all samples of the tested ashes, a higher concentration of Th (0.2–14.8 mg/kg) was found in comparison to U (0.1–6 mg/kg). In ashes from biomass and hard-coal combustion/co-combustion, the range of the prospective coefficient (Coutl) is 0.66–0.82 and 0.8–0.85, respectively, which may suggest a potential source for REE recovery. On the basis of SEM -EDS studies, yttrium was found in particles of ashes from biomass combustion, which is mainly bound to carbonates. The carriers of REY , U, and Th in ashes from biomass and hard-coal co-combustion are phosphates (monazite and xenotime), and probably the vitreous aluminosilicate substance.

Optimization in mine planning could improve the economic benefit for mining companies. The main optimization contents in an underground mine includes stope layout, access layout and production scheduling. It is common to optimize each part sequentially, where optimal results from one phase are treated as the input for the next phase. The production schedule is based on the mining design. Access layout plays an important role in determining the connection relationships between stopes. This paper proposes a shortest-path search algorithm to design a network that automatically connects each stope. Access layout optimization is treated as a network flow problem. Stopes are viewed as nodes, and the roads between the stopes are regarded as edges. Moreover, the decline location influences the ore transport paths and haul distances. Tree diagrams of the ore transportation path are analyzed when each stope location is treated as an alternative decline location. The optimal decline location is chosen by an enumeration method. Then, Integer Programming (IP) is used to optimize the production scheduling process and maximize the Net Present Value (NPV). The extension sequence of access excavation and stope extraction is taken into account in the optimization model to balance access development and stope mining. These optimization models are validated in an application involving a hypothetical gold deposit, and the results demonstrate that the new approach can provide a more realistic solution compared with those of traditional approaches.

Premises for the construction of balance equations of water reserves in the saturation zone of forest soil are presented in this paper. Changes of soil water reserves are dealt with as an effect of the atmosphere-tree stand-soil balance at the assumption of constant ground water flow and negligibly small losses for infiltration down the soil profile below saturation zone. These assumptions are met in permeable lowland forest soils, particularly in areas where the aquifer is situated on relatively shallow impermeable substratum. Then, for snow-free periods, it is possible to: 1) combine the increment of soil water reserves with precipitation above tree crowns and with plant and litter interception and 2) combine the losses of soil water reserves with plant transpiration and evaporation from the soil surface. The periods of increments and losses of soil water reserves are determined from limnigraph records of ground water table depth in piesometers. Examples are given in the paper of equations identified by long term data from 13 soil profiles localised in pine forests on Pleistocene floodplain of the Dunajec River. The data included: ground water table depth, physical properties of grounds in soil profiles, and hydro-climatic conditions. The equations combine increments and losses of water reserves in the saturation zone with rainfall and deficits of air humidity measured on a midforest meadow.

The aim of the work is to present one of the most important structures of the last decade — the European Central Bank in Frankfurt am Main, against the background of the role which a sustainable skyscraper can play in the urban composition of a modern city. A literature query and original in situ research show that from the beginning of the 20th century, skyscrapers have become a symbol of the success and importance of cities and metropolises. At the same time, most of the historic skylines of European cities were saved from ‘Manhattanization’. One of the exceptions is Frankfurt, the financial capital of the EU. This paper discusses the construction of the ECB building, both as another important landmark in the city’s urban composition and as an innovative, sustainable structure. The results show that the location of an important high-rise building with a prestigious function in the urban structure confirms the city’s status. At the same time, it was proved that the technological and formal solutions used in the complex, together with the reuse of the built structure (recycling of architecture), may contribute to the reduction of the carbon footprint and maintaining high environmental standards.

The objective of this paper is a review of data on reconstruction of the Pleistocene palaeogeography (environment) and stratigraphy based on studies of karst sites in the Świętokrzyskie (Holy Cross) Mountains. Although the number of known Pleistocene karst sites in this region is small, the investigations of them have played a crucial role in a research of the Pleistocene. The study of the Kozi Grzbiet site provided the first evidences for new climatostratigraphy and classification of glaciations in Poland. The explanation of genesis of cryogenic calcite crystals discovered in Chelosiowa Jama-Jaskinia Jaworznicka cave system started a new direction of palaeoenvironmental reconstructions of the last glacial period. Kadzielnia palaeontological site was one of the first Early Pleistocene fossil assemblages in karst studied in Poland, whereas Raj cave provided abundant palaeontological and archaeological material from the Last Glacial. Other sites are of less scientific importance, however some of them can be used in education and popularisation of geosciences. Small number of already studied sites does not exclude discoveries of next sites of high scientific importance.

The parameters of sigma-delta audio DAC depend mainly on digital sigma-delta modulator's features, especially on its noise transfer function (NTF). Many methods of design and optimization of the loop filter's coefficients in sigma-delta modulators have been proposed so far. These methods enable the designer to get suitable noise transfer functions for specific application. This paper reviews NTF design and optimization methods which are particularly useful in audio applications.