The paper presents a comparison of selected power technologies from the point of view of emissions of greenhouse gases. Such evaluation is most often based only on analysis of direct emissions from combustion. However, the direct analysis does not show full picture of the problem as significant emissions of GHG appear also in the process of mining and transportation of fuel. It is demonstrated in the paper that comparison of power technologies from the GHG point of view has to be done using the cumulative calculus covering the whole cycle of fuel mining, processing, transportation and end-use. From this point of view coal technologies are in comparable level as gas technologies while nuclear power units are characterised with lowest GHG emissions. Mentioned technologies are compared from the point of view of GHG emissions in full cycle. Specific GHG cumulative emission factors per unit of generated electricity are determined. These factors have been applied to simulation of the influence of introduction of nuclear power units on decrease of GHG emissions in domestic scale. Within the presented simulations the prognosis of domestic power sector development according to the Polish energy policy till 2030 has been taken into account. The profitability of introduction of nuclear power units from the point of view of decreasing GHG emissions has been proved.

Investigations showing the possibility of BTX biodegradation present in the water environment under aerobic conditions have been presented. The effects of transformation of benzene, toluene, o-xylene and p-xylene by indigenous to sewage microorganisms as well as by isolated species of bacteria like Aeronwnas sobria, Bacillus steareothermophilus, Enterobacter sakazaki, Pseudomonas aeruginosa. Staphylococcus lentus and the mixture of these species varied distinctively. The results and calculated degradation rates have been compared to some results given by other authors. In aerobic conditions all investigated aromates have shown to be biodegradable. The highest rate of degradation was found for indigenous to municipal sewage microorganisms.

Production of defect free castings requires good understanding of casting characteristics like mold filling ability and volume deficit characteristic. Pin test piece with cylindrical cores proposed by Engler and Ellerbrok was used to study the mold filling ability. Volume deficit characteristics experiments were conducted using the method designed by Engler. Alloy composition, Mold coat and Pouring temperature were considered as process parameters for the present study and experimental plan has been taken up through design of experiments. The alloy composition is most significant in influencing the mold filling ability, where as pouring temperature is for volume deficit. The Correlation Co-efficient value obtained is -0.98901 indicating strong a negative relation between mold filling ability and volume deficit characteristics. Negative values indicate a relationship between mold filling ability and volume deficit such that as values for mold filling ability increase, for volume deficit decrease.

The perceptual text is the one described by means of sense organs and having specific cohesion tools which include among others lexis belonging to the perception modus, so called introductory predicates indicating specific perception acts, synesthetic expressions, the observer as well as spatial and locative syntactems. Text architectonics is determined by the change of the speaker’s position (observer, perceiver), his transition within the text time and space.

The purpose of this study was to develop a sound quality model for real time active sound quality control systems. The model is based on an optimal analytic wavelet transform (OAWT) used along with a back propagation neural network (BPNN) in which the initial weights and thresholds are determined by particle swarm optimisation (PSO). In the model the input signal is decomposed into 24 critical bands to extract a feature matrix, based on energy, mean, and standard deviation indices of the sub signal scalogram obtained by OAWT. The feature matrix is fed into the neural network input to determine the psychoacoustic parameters used for sound quality evaluation. The results of the study show that the present model is in good agreement with psychoacoustic models of sound quality metrics and enables evaluation of the quality of sound at a lower computational cost than the existing models.

Activated sludge systems designed for enhanced nutrients removal are based on the principle of altering anaerobic and aerobic conditions for growth ofmicroorganisms with a high capacity of phosphorous accumulation. To avoid return of large parts of accumulated phosphorous in the processes of sludge conditioning chemical precipitation is often applied. This can be not be the case, at least for a part, if prior to other processes of sludge handling, the sludge will be disintegrated. It was demonstrated that disintegration of surplus activated sludge permits removal of a substantial part of nutrients in the form of struvite. The effects of sludge disintegration on metals ions release and poly-P destruction were elucidated. Appropriated handling of disintegrated sludge allows for removal of at least 25% of the inflowing phosphorous load without addition of chemicals.

Permanent grasslands – according to the Water Framework Directive – are typical water related ecosystems so they largely affect water quality, its cycling and balance and therefore deserve protection. They are an element of landscape structure (ecosystem function or service) commonly considered a factor stabilising environmental changes.

Most threats posed to waters in Poland originate from present cropland structure with its definite predominance of arable lands over grasslands. Agriculture should therefore focus on the improvement of land use structure in order to minimise environmental hazards and to guarantee at the same time optimum economic effects. This could be achieved by turning arable lands into grasslands (where justified e.g. on light soils) or at least by maintaining present grassland area (condition in negotiations with the EU) and management that would consider environmental protection.

Increasing the contribution of grasslands to cropland structure or at least maintaining their pre-sent status quo would help to achieve compromise between the goals of farmers and environmental protection. Purposeful utilisation of ecosystem services, particularly those of grasslands, allows to maintain more intensive farming without environmental hazard. Limited should be only such activi-ties whose intensity exceeds regenerative or buffering environmental capacity e.g. on grounds par-ticularly subjected to water pollution or those included into Natura 2000 network.

The problem of effective gas extraction from Polish shale rocks is an interesting research subject for scientists. A properly selected proppant, which protects cracks from closing during the fracturing process, inestimably contributes to an increase of extraction. Grains of proppant are transported along with a fracturing medium to reach the deepest regions of the crack. The proper support of the crack provides an easy flow of gas, therefore it is important in terms of extraction efficiency. This paper shows the interactions of a proppant grain with the crack surface in shale rock. FEM analysis was conducted to observe the stress region, which is generated as a result of pressing the grain into the crack surface. A model of a sphere which was pressed into the rock model with constant velocity was applied. The received results of stress depend on material properties and a range of proppant grain pressing.