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Number of results: 6
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Abstract

The research involved coal from 11 coal mines in the USCB in Poland, intended for combustion in power plants and for home furnaces. It has been stated that the content of As, Cd, Co, Cr, Cu, Mo, Ni, Pb, Sb and Zn in the ash of coal fines from the USCB with a density of <1.30 × 103 kg/m3 is the largest, and in the ash fraction with a density >2.00 × 103 kg/m3 is the smallest The fraction ash of coal fine with a density> 2.00 × 103 kg/m3 has the greatest impact on the content of As, Cd, Co, Cr, Mo, Pb and Zn in whole coal fines from the USCB. In turn, the largest impact on the content of Cu, Ni and Sb in whole fine coal ash has the fraction of coal fine having a density of 1.60–2.00 × 103 kg/m3 (for Cu) and fraction with a density <1.35 × 103 kg/m3 (Ni and Sb). The main carriers of elements in fine coal ash, thus in future furnace waste, are the grains of aluminosilicates and iron oxides resulting from the combustion of probably fusinite and semifusinite and the combustion of adhesions of these macerals with dolomite, ankerite and pyrite. The purification of fine coal from the matter with a density >2.00 × 103 kg/m3 may reduce the sulfur content (by 40%), the content of main element oxides (from 33% to 85%) and the content of ecotoxic elements (from 7% to 59%) in fine coal ash, i.e. in potential furnace wastes. Due to the small content of mineral matter, ash and sulfur in coal, small content of Al, Fe, Ca, Mg, Na, K, P oxides and high content of SiO2 in coal ash, low value of the Rogi sinterability index, small inclination of coal fine to slag the furnaces and boiler fouling by sludge, the investigated coal was favorable for technological reasons, fuel in power plants and for home furnaces
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Abstract

A forecast of the negative impact exerted on the environment by selected trace elements in “Bełchatów” Power Plant has been prepared on the basis of the results of investigations into these elements’ distribution carried out as part of earlier research on coal from “Bełchatów” Field and the data on updated analyses of the content of these elements in 55 brown coal samples from test boreholes. Work in “Bełchatów” Power Plant, which is supplied with coal from “Szczerców” Field, will be accompanied by trace elements transfer. On the basis of the conducted investigations it has been found that the biosphere is most threatened by mercury emissions. As shown by the presented results of analyses and calculations, the emissions of mercury in “Bełchatów” Power Plant are low. Mercury is accumulated chiefl y in gypsum produced in the FGD plant. The content of mercury in slag and ash is low.
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Abstract

Background concentrations of main trace elements and polycyclic aromatic hydrocarbons (PAHs) were investigated in pristine soils of the Beliy Island situated in the Kara Sea, Yamal autonomous region, North-West Siberia, Russia. Belyi Island is considered as reference landscpae for further investigation of soil polychemical contamination of the Yamal region. Three plots with different functional load (mature ecosystem, occasionally and permanently affected plots) were investigated with aim to evaluate the trend of long term polychemical effect on Stagnic Cryosols - benchmark soil type of the Yamal region. Accumulation of trace elements was not fixed in all soils investigated due to absence of direct sources of heavy metals on the territory of the Beliy Island. At the same time, there were essential alterations of PAHs fractional composition and content due to pronounced accumulation of the petroleum products combustion in the vicinity of the permanent meteorological station and former seasonal field base. The most intensive and statistically significant accumulation was noted for phenanthrene, anthracene, benzo[k]fluoranthene and benzo[a]pyrene. This indicates accumulation of the PAHs in soils, affected by the anthropogenic activity on the meteorological station. The most pronounced differences were revealed for the superficial layer of 0-5 cm. Deeper horizons of soil did not show accumulation of contaminants. Data obtained can be used for organization of further monitoring of contamination of soils and landscapes in Yamal as developing and industrial region.
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Abstract

Objective: The goal of this contribution is to present and familiarize the medical community with the method for the assessment of trace and essentials elements in prostate tissue sections. Materials and methods: X-ray fl uorescence based technique (namely Synchrotron Induced X-ray Emission (SRIXE)) is described in terms of methodology, sample preparation and the evaluation of the recorded results (spectral data sets). Materials for the samples were collected from the patients underwent radical prostatectomy due to Adenocarcinoma prostatae. Specimens were freeze-dried, cut by microtome (to the thickness of 15 μm), one slice was placed on Mylar foil (for SRIXE measurements) and adjacent one on microscopic glass (for histopathological assessment). Results: Results presented here show the usability of SRIXE method for the evaluation of concentration of trace and essential elements in prostate tissue sections with the spatial resolution better than 15 microns. Discussion: Histopathological analysis of samples, which is only focused on morphological features, is unable to reveal information about changes in biochemical signature of tissues aff ected by the illness. SRIXE is a powerful and promising technique to analyse even very low concentrations of selected elements at the cellular level without any labelling or separating procedures. Obtained results may be correlated with classic histopathological assessment allowing for drawing conclusions on the changes in certain elements concentrations with the progression of disease. Moreover, mentioned in this work analysis, can be performed for any type of biological tissues.
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Abstract

Trace elements contained in coal escape with flue gas from energy sources into the air or move towards other components of the environment with by-products captured in electrofilters (EF) and flue gas desulphurisation (FGD) plants. The existing knowledge about the distribution of frequently dangerous trace elements contained in these products is insufficient. Studies were therefore undertaken in selected power plants to investigate the distribution of trace elements in coal, slag, as well as dust containment and flue gas desulphurisation products, such as fly ash captured in dust collectors, desulphurisation gypsum and semi-dry scrubbing FGD products. Using the technique of flame atomic absorption spectrometry (F-AAS) and mercury analyser, the following were determined in the research material samples: Cr, Cu, Hg, Mn, Ni, Pb and Zn. The studies have a reconnaissance character. The authors have presented the results of determinations for selected trace elements in samples taken at Jaworzno III and Siersza Power Plants, which burn hard coal, and in Bełchatów Power Plant, burning brown coal. A balance of the examined trace elements in a stream of coal fed into the boiler and in streams of waste and products carried away from the plant was prepared. The balance based on the results of analyses from Bełchatów Power Plant was considered encouraging enough to undertake further investigations. The research confirmed that due to the distribution in the process of coal combustion and flue gas treatment, a dominant part of particular trace elements’ stream moves with solid waste and products, while air emission is marginal. Attention was paid to the importance of research preparation, the manner of sample taking and selection of analytical methods.
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Abstract

Trace elements Co, Cr were added to investigate their influence on the microstructure and physical properties of Al-Si extruded alloy. The Co, Cr elements were randomly distributed in the matrix, forms intermetallic phase and their existence were confirmed by XRD, EDS and SEM analysis. With addition of trace elements, the microstructure was modified, Si particle size was reduced and the growth rate of β-(Al5FeSi) phase limited. Compared to parent alloy, hardness and tensile strength were enhanced while the linear coefficient of thermal expansion (CTE) was significantly reduced by 42.4% and 16.05% with Co and Cr addition respectively. It is considered that the low CTE occurs with addition of Co was due to the formation of intermetallic compound having low coefficient of thermal expansion. The results suggested that Co acts as an effective element in improving the mechanical properties of Al-Si alloy.
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