The aim of this paper is an analysis of the variability of the methane content in coal seams in the area of the Dębieńsko Mine and it’s relation to the geological structure of this coal deposit, and also the possibilities of a methane hazard in the areas of future coal mining and methane utilization as a fuel. The Dębieńsko coal deposit is located in the western part of the Upper Silesian Coal Basin (USCB), on the boundary between folded and disjunctive tectonic zones. Coal exploitation in this area ended in 2000, but interest in this deposit is currently high due to plans to initiate coking coal mining. The area of the Dębieńsko mine is relatively well prospected because of the deep drillings (up to 2000 m in depth) carried out within it. The methane conditions of the deposit are varied, the methane content increases with depth according to northern pattern of methane distribution in the USCB, in which the high-methane zone occurs under the several hundred meters zone of natural outgassing of the coal seams. This zone is divided into two smaller methane sub-zones, the first (shallower) at a depth of 1000 m and the second (deeper) at 1700–1900 m. A sub-zone of lower methane content occurs between these two high-methane sub-zones. The most important reasons for this methane distribution are temperature and pressure facilitating the gas adsorption in coal seams, and also the presence of impermeable siltstones and shalestones as well as the maceral composition and coal rank of coal seams. The methane content also changes laterally in accordance with the tectonics of the area. The so called Knurów and Leszczyna Anticline with found increased methane content in coal seams in relation to neighboring areas as well as Orlova Overthrust together with the system of latitudinal faults of brittle tectonic regime which are possible pathways for methane migration play a special role here. These structures can be taken into account as a potential source of methane hazard in a future coal mine, they can also be promising structures for methane prospection as a fuel.

The new legislative provisions, regulating the trade in solid fuels in our country, draw attention to the need to develop and improve methods and methods of managing hard coal sludge. The aim of the work was to show whether filtration parameters (mainly the permeability coefficient) of hard coal sludge are sufficient for construction of insulating layers in landfills at the stage of their closing and what is the demand for material in the case of such a procedure. The analysis was carried out for landfills for municipal waste in the Opolskie, Śląskie and Małopolskie provinces. For hard coal sludge, the permeability coefficient values are in the range of 10–8–10–11 m/s, with the average value of 3.16 × 10–9 m/s. It can be concluded that this material generally meets the criteria of tightness for horizontal and often vertical flows. When compaction, increasing load or mixing with fly ash from hard coal combustion and clays, the achieved permeability coefficient often lowers its values. Based on the analysis, it can be assumed that hard coal sludge can be used to build mineral insulating barriers. At the end of 2016, 50 municipal landfills were open in the Opolskie, Śląskie and Małopolskie Provinces. Only 36 of them have obtained the status of a regional installation, close to 1/3 of the municipal landfill are within the Major Groundwater Basin (MGB) range. The remaining storage sites will be designated for closure. Assuming the necessity to close all currently active municipal waste landfills, the demand for hard coal sludge amounts to a total of 1,779,000 m3 which, given the assumptions, gives a mass of 2,704,080 Mg. The total amount of hard coal sludge production is very high in Poland. Only two basic mining groups annually produce a total of about 1,500,000 Mg of coal sludge. The construction of insulating layers in landfills of inert, hazardous and non-hazardous and inert wastes is an interesting solution. Such an application is prospective, but it will not solve the problem related to the production and management of this waste material as a whole. It is important to look for further solutions.

Determined concentrations of BTEX and PAHs in bottom sediments of strong polluted dam- reservoir Dzierżno Duże (Western Part of Upper Silesian Region in South of Poland) are presented. Hydrocarbons (PAH) concentrations have not grown since 1979. The effect of adaptation process of microbiological groups to PAH degradation over the long period of pollution in the anthropogenic ecosystem is presented. Organic pollutants are deposited in the bottom of the Kłodnica river estuary. Total PAHs concentration in bottom sediments was estimated about 30 mg/kg dry weight near the Kłodnica estuary and it gradually decreases. In the distance of 700 m from first part of the water reservoir, PAH concentration is lower than 80% of the concentration, which was determined in the first sampling points of the estuary. In the present ecosystem the hydrocarbons are the element of strong environmental contamination.

The paper discusses thermodynamic phenomena accompanying the flow of gas in a slotted seal. The analysis of the gas flow has been described based on an irreversible adiabatic transformation. A model based on the equation of total enthalpy balance has been proposed. The iterative process of the model aims at obtaining such a gas temperature distribution that will fulfill the continuity equation. The model allows for dissipation of the kinetic energy into friction heat by making use of the Blasius equation to determine the friction coefficient. Within the works, experimental research has been performed of the gas flow in a slotted seal of slot height 2 mm. Based on the experimental data, the equation of local friction coefficient was modified with a correction parameter. This parameter was described with the function of pressure ratio to obtain a mass flow of the value from the experiment. The reason for taking up of this problem is the absence of high accuracy models for calculating the gas flow in slotted seals. The proposed model allows an accurate determination of the mass flow in a slotted seal based on the geometry and gas initial and final parameters.

Weak mysterianism defines the situation in philosophy of mind in which we can neither formulate a solvable problem of consciousness nor prove that it is unsolvable. To develop the issue the author starts with a description of the theories and concepts described as mysterious. General mysterianism is a position in the philosophy of mind, according to which we are admittedly able to indicate scientific issues but cannot formulate them as scientific problems and thus solve them. These issues are called ‘mysteries’ by Noam Chomsky. The article presents several argumentation strategies typical for mysterian theories – evolutionary closure, autonomy of consciousness, and methodological mysterianism of William Seager. Each is subject to criticism, which shows that the mysterian argumentation is non-conclusive. It turns out, therefore, that the problem of mysteriousness is that indicating the possibility of mysteries in science does not entail a proof that we are dealing with specific mysteries (first and foremost the mystery of the mind).

The present work deals with continuum mechanical considerations for deformable and rigid solids as well as for fluids. A common finite element framework is used to approximate all systems under considerations. In particular, we present a standard displacement based formulation for the deformable solids and make use of this framework for the transition of the solid to a rigid body in the limit of infinite stiffness. At last, we demonstrate how to immerse a discretized solid into a fluid for fluid-structure interaction problems.

The paper discusses the problems of the calibration process of very close range semi-metric digital cameras. Using such cameras for precise measurement of small objects, the photographs have to be taken at a very large scale, ranging from 1 :20 to 1:50. To ensure the submillimetre accuracy of the photogrammetric measurement, the specific calibration tests and procedures for determination of the interior orientation parameters, including the coefficients for image systematic errors, must be applied. The results of two calibration approaches, based on 3D and 2D calibration tests, have been presented in the paper. The experiment is a part of the research project concerning the numerical modelling of small 3D fragments of the broken archaeological items for reconstruction of the context of the archaeological monument.

It was assumed that the temperature at which caffeine is consumed may cause changes in the mechanical and morphological properties of bones and affect the bone metabolism of pregnant female. The aim of the study was to assess the effect of caffeine used at different temperatures on selected morphological and mechanical properties of the femur as well as biochemical indicators of bone formation in female rats in pregnancy. It was use test solution at the temperature 10, 25 and 45ºC from 8 to 21 day during pregnancy, once a day. It was found that the temperature of administrated caffeine may have an effect on changing the morphometric properties and on the bone metabolism of pregnant female rats. The application of caffeine solution, was administrated at 10ºC caused the most constrained growth of the femur and weakened resistance to load, and caused increased susceptibility to cracks. Analysis of bone metabolism indicators showed that caffeine administered in the form of a solution at 10ºC and 25ºC caused the most negativity effects for bone formation and bone turnover indicators. The administration of caffeine at 10ºC causes the largest negative changes in bone morphological and strength indicators and hasn’t a beneficial effect on the bone metabolism of pregnant female rats.