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Abstract

Abstract Biscutella laevigata L. is known as a Tl hyperaccumulator. In Poland Biscutella laevigata occurs in the Tatra Mts (Western Carpathians) and on the calamine waste heap in Bolesław near Olkusz (Silesian Upland). The purpose of this work was to evaluate whether plants of both populations were able to accumulate an elevated amount of thallium in their tissues. The plants were cultivated in calamine soil in a glasshouse for a season and studied at different ages – from 2-week-old seedlings to 10-month-old adults. Additionally, the plants were grown for ten weeks in calamine soil with EDTA to enhance Tl bioavailability. The total content of Tl in plant tissues after digestion was determined by ICP-MS, whereas its distribution in leaves was studied by LA-ICP-MS. Of the total content of Tl in the soil in the range of (15.2–66.7) mg∙kg−1d.m., only (1.1–2.1) mg∙kg−1d.m. was present in a bioavailable form. The mean content in all the plants grown on the soil without EDTA was 98.5 mg∙kg−1d.m. The largest content was found in leaves – 164.9 mg∙kg−1d.m. (max. 588.2 mg∙kg−1d.m.). In the case of plants grown on the soil enriched with EDTA, the mean content in plants increased to 108.9 mg∙kg−1d.m., max. in leaves – 138.4 mg∙kg−1d.m. (max. 1100 mg∙kg−1d.m.). The translocation factor was 6.1 in the soil and 2.2 in the soil with EDTA; the bioconcentration factor amounted to 10.9 and 5.8, respectively. The plants from both populations did not contain a Tl amount clearly indicating hyperaccumulation (100–500 mg∙kg−1d.m.), however, high (>1) translocation and bioconcentration factors suggest such an ability. It is a characteristic species-wide trait; B. laevigata L. is a facultative Tl hyperaccumulator. The largest Tl amount was located at the leaf base, the smallest at its top. Thallium also occurred in trichomes, which was presented for the first time; in this way plants detoxify Tl in the above-ground parts. Leaves were much more hairy in the Bolesław plants. This is an adaptation for growth in the extreme conditions of the zinc-lead waste heap with elevated Tl quantity.
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Abstract

The paper discusses the current situation as well as the perspectives for hard coal extraction in India, a global leader both in terms of hard coal output and import volumes. Despite this, over 300 million people lack access to electricity in this country. The main energy resource of India is hard coal and Coal India Limited (CI L) is the world’s biggest company dealing with hard coal extraction. CI L has over 450 mines, employs over 400,000 people, and extracts ca. 430 million tons of hard coal from its 471 mining facilities. India is planning the decisive development of hard coal mining to extract 1.5 billion tons in 2020. Hard coal output in India can be limited due to the occurrence of various threats, including the methane threat. The biggest methane threat occurs in the mines in the Jharia basin, located in East India (the Jharkhand province), where coal methane content is up to ca. 18 m3/Mg. Obtaining methane from coal seams is becoming a necessity. The paper provides guidelines for the classification of particular levels of the methane threat in Indian’s mines. The results of methane sorption tests, carried by the use of the microgravimetric method on coal from the Moonidih mine were presented. Sorption capacities and the diffusion coefficient of methane on coal were determined. The next step was to determine the possibility of degassing the seam, using numerical methods based on the value of coal diffusion coefficient based on Crank’s diffusion model solution. The aim of this study was the evaluation of coal seam demethanization possibilities. The low diffusivity of coal, combined with a minor network of natural cracks in the seam, seems to preclude foregoing demethanization carried out by means of coal seam drilling, without prior slotting.
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Abstract

Główne pytanie tekstu dotyczy wchodzenia w dorosłość młodych Polaków w wieku 18-29 lat, ich postrzegania dorosłości. Zgodnie z wynikami badania młodzi odchodzą obecnie od definiowania dorosłości w kategoriach tradycyjnych markerów społecznych na rzecz własności intrapsychicznych oraz kompetencji. Dorosłość jest silnie związana z postrzeganiem siebie jako osoby kompetentnej w obszarze zawodowym i relacji społecznych, z pewną autonomię. Markery te (kompetencji, relacji, autonomii) na poziomie mikro odpowiadają najważniejszym potrzebom psychicznym człowieka (teoria autodeterminacji). Na poziomie makro markery te są zbieżne z charakterystyką czterech europejskich modeli wchodzenia w dorosłość, stworzonych przez Cécile van de Velde. Polski model wydaje się mieć charakter hybrydowy, łączący dużą rolę kompetencji zawodowych i autonomii z naciskiem na samorozwój jednostki.
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Abstract

Protection of the environment and counteracting global warming require finding alternative sources of energy. One of the methods of generating energy from environmentally friendly sources is increasing the share of gaseous fuels in the total energy balance. The use of these fuels in compression-ignition (CI) engines is difficult due to their relatively high autoignition temperature. One solution for using these fuels in CI engines is operating in a dualfuel mode, where the air and gas mixture is ignited with a liquid fuel dose. In this method, a series of relatively complex chemical processes occur in the engine's combustion chamber, related to the combustion of individual fuel fractions that interact with one another. Analysis of combustion of specific fuels in this type of fuel injection to the engine is difficult due to the fact that combustion of both fuel fractions takes place simultaneously. Simulation experiments can be used to analyse the impact of diesel fuel combustion on gaseous fuel combustion. In this paper, we discuss the results of simulation tests of combustion, based on the proprietary multiphase model of a dual-fuel engine. The results obtained from the simulation allow for analysis of the combustion process of individual fuels separately, which expands the knowledge obtained from experimental tests on the engine.
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Abstract

Archaeometallurgical investigations presented in this work focus on analysing the microstructure as well as mechanical properties of artefacts from the17th in form of findings performed from cast iron as well as copper casts. The presented research results extend the up-to-date knowledge and present the analysis of structural compounds found in the microstructure of the artefacts from the time dating back to the late Middle Ages in the region around Czestochowa, Poland. The tested samples were found in earth in the city centre under the present marketplace. The excavation works were carried out in summer in the year 2009, and have resulted in the excavation of artefacts in form of copper block of the weight of several kg. The excavation action was led by a group of Polish archaeologists collaborating with the local authorities. The performed pre-dating of this element determines the age of the artefacts as the 17th century AD. The excavations that have been taking place since 2007 have widened the knowledge of the former Czestochowa. Historians of this town have suggested, that the found weight and traces of metallurgical activity suggest that the exposed walls were an urban weight. The weight is visible on the 18th century iconography. What was find on the Old Market indicates that there was a lush economic life before the Swedish invasion in this part of Poland. Some buildings lost their functions or were changed, others died in fires, but new places developed. To describe the microstructure, with its structural components, research was done using microscopy techniques, both of the light as well as electron microscopy (SEM), also chemical composition analysis was carried out using the EDS technique, as well as tool for phase analysis were applied in form of X-Ray Diffraction (qualitative analysis), especially for the reason to describe the phases present in the excavated material. This research will help to obtain new information in order to investigate further archaeometallurgical artefacts, extending the knowledge about middle age metallic materials its usage and manufacturing.
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