In the present paper results of the studies devoted to computer simulations of dielectric response of electroceramics in a frequency domain as well as analysis of the experimental data are given. As an object of investigations BiNbO4-based microwave ceramics was taken. Simulations of the hypothetical impedance response of the ceramic system were performed under assumption of the brick-layer model. A strategy for analysis and modelling of the impedance data for microwave electroceramics was discussed. On the base of the discussed strategy modelling of the dielectric response of BiNbO4 ceramics was performed with the electric equivalent circuit method. The Voigt’s and Maxwell’s circuits were taken as electric models. Parameters of the electric components of the circuits were determined and related to parameters of the ceramic object under study. It was found that fitting quality was good and changed within the range χ2 = 6.78 × 10–4 – 6.77 × 10–5 depending on the model.

Planning in a mining enterprise is a complex and multifaceted action. For this reason, it is necessary to provide its proper organisation and adjust it to the specific conditions of conducting underground mining extraction. The prepared plans must make up a cohesive internal system, unambiguously determining the manner, range and safety requirements of the conducted extraction. In the most general manner, the various types of plans developed by organisational units of mining enterprises can be divided based on the timeframe, type, scope and object of planning. These are strategic plans, tactical plans and subject-based plans. The aim of the article is to present the issue of production planning in a mining enterprise and for the preparation of such a plan, first and foremost, information about, among other things, applicable legal regulations, market conditions and the specificity of a mining enterprise are necessary. Underground extraction of black coal deposits must be conducted while respecting the rules of sustainable development which satisfies current needs, without compromising the ability to satisfy the needs of future generations. Due to the specific nature of mining production, manifested, among other things, by such features as the diversity of conditions for conducting the activity, resulting from the changing geological-mining conditions of the deposit, low flexibility of the production process, associated with the impossibility to conduct alternative production and a very long-lasting investment process, planning the course and magnitude of production in a mining enterprise must proceed with the highest possible diligence. One should take into account a wide range of presented environmental, organisational and technical conditions, deciding about the safety and correctness of the course of the assumed production activities. However, in order to make them economically feasible and produce satisfying results in that regard, it is also necessary to analyse them carefully with respect to financial outcomes

The Polish basis of dolomites is remarkable. Their total reserves reported in the 62 deposits listed in current data bases of mineral resources amount to 1,500,000 t. However, there is a shortage of the so-called converter dolomites of high quality applicable in manufacturing of refractory materials. Such dolomites of the Triassic age have been quarried for many years in the Brudzowice and Ząbkowice Śląskie I deposits in the Silesian-Cracow region. The Libiąż deposit is perspective of this area, considering the character and properties of its dolomites. The dolomites of the Nowa Wioska and Stare Gliny deposits belong into the same group although their applying as refractories seems to be disputable at the moment and would require more detailed analyses of the chemical composition and firing properties of the rocks mentioned. The reason is that the dolomites of these deposits have been reported andmassively quarried up to now mainly for civil engineering (roads, buildings, etc.). Unfortunately, worsening properties of the dolomites occurring in Żelatowa, still another large and developed deposit of the region, have been excluded using these rocks in producing of refractories. Among the group of reserve converter dolomite deposits, the best rock properties have been found in four of them, i.e., Chruszczobród, Chruszczobród I, Chruszczobród II and Libiąż Wielki. The survey presented indicates that there are some possibilities of including dolomites of the Winna and, to a lesser degree, Radkowice-Podwole deposits as the raw materials in manufacturing of refractories. Again, more detailed analyses of the chemical composition and petrographical development, mainly of the grain size distribution, would be required. Dolomitic marbles of the Lower Silesia region represent a separate problem. Traditionally, they have been considered to be non-applicable in manufacturing of refractories because of too coarse grain size of these rocks. It should be stressed, however, that the Lower Silesian marbles occur in several varieties and among them also fineand coarse-grained dolomites occur. Their finest and chemically purest varieties can be an interesting option in extending the basis of refractory dolomitic raw materials in Poland, although selective quarrying would be required in such a case.

In the present study, the lead-free BaTi1-xZrxO3 (for x = 0, 0.05 and 0.15) ceramics were prepared by High-Energy Ball Milling and heat treatments. The performed X-ray, SEM and EDS measurements confirmed high purity, good quality and the expected quantitative composition of the obtained samples. The study of dielectric properties was performed by means of broadband dielectric spectroscopy at the frequency ranging from 0.1 Hz to 10 MHz. The obtained measurement data, analyzed in accordance with the Arrhenius formalism demonstrated the presence of relaxation type dielectric mechanisms. The impedance answer of studied ceramic materials indicated the presence of two relaxation processes: one with a dominant resistive component and the other with a small capacitive component. The observed dielectric relaxation process is temperature dependent and has a “non-Debye” character.

Goal of the present research was to apply a solid state reaction route to fabricate bismuth layer-structured multiferroic ceramics described with the formula Bi5FeTi3O15 and reveal the influence of processing conditions on its crystal structure and phase composition. Simple oxide powders Bi2O3, TiO2 and Fe2O3 were used to fabricate Aurivillius-type bismuth layer-structured ferroelectrics. Pressureless sintering in ambient air was employed and the sintering temperature was TS = 900°C, TS = 1000°C and TS = 1040°C. The phase composition as well as crystal structure of ceramics sintered at various processing conditions was examined with powder X-ray diffraction method at room temperature. The Rietveld refinement method was applied for analysis of X-ray diffraction data. It was found that ceramics adopted orthorhombic structure Cmc21. The unit cell parameters of bismuth layer-structured multiferroic ceramics increased slightly with an increase in sintering temperature.

Polycrystalline samples BaTiO3 and the solid solutions Ba0.9Sr0.1TiO3, Ba0.9Sr0.1Ti0.9Sn0.1O3, Ba0.9Sr0.1Ti0.8Sn0.2O3 were obtained by means of a mechanochemical treatment based on the high-energy ball milling technique and next a high temperature solid state reaction method. The influence of synthesis condition on microstructural, dielectric and ferroelectric properties of obtained solid solutions were investigated. The structure and morphology of the investigated samples were characterized by an X-ray diffraction (XRD) and scanning electron microscopy (SEM). The characterization of electrical properties of the ceramics within the temperature range from –130°C to 250°C were performed by means of a dielectric spectroscopy method at the frequency ranging from 0.1 Hz to 10 MHz. The diffusion of the paraelectric – ferroelectric phase transition and dielectric relaxation for ceramic samples are described.

Among the collections of the Saxon State and University Library Dresden (SLUB – Sächsische Landesbibliothek– Staats- und Universitätsbibliothek Dresden) there are two handdrawn maps of the Kamieniec Podolski stronghold, so far unpublished in Poland, one by Johann Georg Starcke, and the other by J. G. M. Fürstenhoff.

W zbiorach Państwowej Uniwersyteckiej Biblioteki Saksońskiej w Dreźnie (SLUB – Sächsische Landesbibliothek – Staats- und Universitätsbibliothek Dresden) znajdują się dwa rękopiśmienne, dotychczas niepublikowane w Polsce plany Kamieńca Podolskiego: pierwszy sporządził Johann Georg Starcke, drugi wykonał J. G. M. Fürstenhoff.

In order to fully adapt to market requirements, mining enterprises in recent years have implemented standardized systems for quality, safety and health at work and environmental management. The standards for individual systems define the requirements of applying specific procedures and actions to implement the adopted policy aimed at achieving the assumed goals. The combination of business procedures and practices is more effective in the case of their integration than the activities carried out under separate systems. They then function under the name of an integrated management system (IMS). Properly implemented IMSs most often contributes to a more harmonious functioning of the enterprise and the elimination of recurring activities in the areas concerning individual systems, and thus to the optimization of costs related to their implementation and maintenance. Improving the operational efficiency of the mining enterprise and mines included in it, while maintaining the requirements of work safety and environmental protection. In the conditions of a market economy, improving the efficiency of functioning and providing sources of business financing is a key necefity for mining enterprise (Bąk 2007, 2008). Mines need to be properly managed to survive. The key problem is the design and implementation of an efficient management system and its continuous improvement based on the adequacy of system solutions. This is an answer to the question whether the management system of a mining enterprise (mine) corresponds to its real needs in the process of achieving objectives. Improvement of management systems must be based on an appropriate diagnosis. The aim of the article is to present the original solution, which is a tool for improving the integrated management system in Polish mining enterprises.

The assurance of future raw materials supply to the EU mineral industry has become, in recent years, one of the priority tasks of the EU Commission, geological surveys and several research centers. After many years of negligence, the problem of developing supply risk of many raw materials in Europe has been perceived, along with the menace to the EU economy competitiveness coming from dynamically developing countries such as China, India and others - basically of Asian origin. This has initiated a new mineral policy within the EU zone, referring mainly to non-fuels. One of the starting points for this activity has become the assessment of the EU mineral resources potential and identification of the raw materials that are critical for the harmonious and sustainable development and technological progress. The paper briefly presents the results of research work focused on the critical raw materials assessment, which were conducted by the Initiative for the Raw Materials Supply. Its core is the presentation of Polish mineral reserve base and its potential as a possible source of critical raw materials for the European Union. The criticality analysis was based on three categories, i.e.: economic consequences of the supply limitation, supply risk of reduction (fluctuation or disruption), and environmental risk referring to countries with weak environmental performance in order to protect the environment that jeopardize the supply of raw materials to the EU. For their quantitative assessment there were proposed three aggregated indices, while for the forecast purposes - 10-year period. The criticality ratio was determined for the 41 most important and most frequently used raw materials. On the grounds of the research made up to now, these raw materials were preliminary divided into three groups. As a critical to the EU economy, 14 raw materials of major economic importance were discriminated, i.e.: antimony, beryllium, cobalt, fluorite, gallium, germanium, graphite, indium, magnesium, niobium, PGM, rare earths, tantalum, and tungsten. They are characterized by high supply risk, which is mainly due to limited number of their sources - dominated by a few countries, in particular China. The risk of supply disruptions is boosted by low rate of utilization of secondary sources, and limited scale of substitution as well. The majority of the above-mentioned raw materials are crucial for the new technologies development. The remaining minerals arealso - though to a lesser extent - imperiled with a supply deficit. Despite they are also of economic importance, their indispensability for the advanced technologies development is relatively smaller. Taking into account the raw materials that are critical for the European Union economy, Poland cannot be considered as its resource base. The source of these raw materials are not only scarce in Poland, but also they are not produced, and their demand is now - and according to forecasts is going to be in the future - met by imports. However, the role of our country as a manufacturer of finished products from components of foreign origin is anticipated to increase. The raw materials in question are not considered exactly critical for Polish economy, as any industrial branch based upon their utilization has emerged so far. Therefore, they are of limited economic importance. Presumable utilization of very limited sources of above-mentioned critical raw materials in Poland could be anticipated in a perspective of at least 20 years. The most probable in this respect are the following: opening out the new Mo-W-Cu ore deposit Myszków, and the promotion of exploration works for similar deposits.

The radiolarian biostratigraphy of the Middle–Upper Jurassic pelagic siliceous sediments (Czajakowa Radiolarite

Formation) in the Niedzica succession of the Pieniny Klippen Belt (Carpathians) is interpreted in terms of their

age in a stratotype section, and facies equivalents in other tectonic-facies units of this region. The siliceous sediments

are represented by radiolarian cherts and silicified limestones which are underlain and overlain by red nodular

limestones, equivalents of the Rosso Ammonitico facies. The radiolarian association includes thirty-seven

taxa belonging to twenty one genera which represent the Northern Tethyan Palaeogeographic Province. Key radiolarians

recorded provide a means of correlation with zonation schemes based on Unitary Associations defined

for the Jurassic Tethyan sediments. The age of the Czajakowa Radiolarite Formation in the stratotype section

is determined as U.A.Z.9 to U.A.Z.11 corresponding to middle Oxfordian up to Kimmeridgian. Comparison of

radiolarian biozones from the stratotype section with other facial equivalent sections in the Pieniny Klippen Belt

reveals a significant diachronism for both the lower and the upper limits of the Jurassic pelagic siliceous facies.