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This paper characterizes the influence of a wastewater treatment plant with activated sludge aerated by CELPOX devices on the microbiological properties of the air at the plant grounds and in the vicinity. Field studies by the sedimentation method were carried out in seven measurement series in 2001. Sampling posts were each time set with regard to the current meteorological conditions like wind speed and wind direction. Microbiological analyses were comprised of: heterotrophic bacteria at 37şC and 26şC, hemolytic bacteria at 37şC and 10şC, staphylococci mannitol-fermenting and non-fermenting, Escherichia coli, coliforms Pseudomonas, enterococci, actinomycetes, yeasts and moulds. The results indicate that generally - in accordance with the Polish Standards [1,2] the air at the plant grounds and in its vicinity was not polluted. However, few spots (mostly in some distance from the plant) were detected where a group of microorganisms was present in increased numbers which has qualified the air as polluted. Biological aerosols from the activated sludge tanks were not generated in considerable amounts, which was confirmed by the absence or small number of faecal bacteria (coliforms, enterococci), absence of mannitol-fermenting straphylococci and typical water-sewage bacteria of the Pseudomonas fluorescens. The main sources of microbiological pollution were the grit removal chamber and the secondary settlers.
The effects of unemployment also include consequences for health that are experienced by the unemployed themselves and by their families and in a broader social scale. The aim of the study was to evaluate the influence of unemployment on the health condition of the unemployed in the Lublin Region. The study was carried out in 2000-2003 and included 1560 subjects that were the unemployed registered in the Municipal and Provincial Labour Offices in Lublin, Świdnik, Lubartów, Puławy and Kraśnik. The research tool was a questionnaire survey and the research method was a diagnostic sounding.
Concentrations of accumulated heavy metals were compared between the terrestrial bryophyte Pohlia nutans and needles and bark of Larix decidua collected on a dump situated in the vicinity of coke- and sulphuric acid-producing factories and a municipal thermal-electric power station. The dump consisted of heavily polluted mine and smelter wastes located near Walbrzych (southwestern Poland). The plant samples were compared with material of the same species from the control site. In the examined area needles and bark can be considered as suitable biomonitors for atmospheric pollution for Co, Cu, Ni and Pb. Bioaccumulation abilities of Pb in P. nutans and L. decidua needles and Ni in P. nutans and L. decidua bark were similar. Compared to each other needles were better accumulators of Ni and the moss P. nutans was a better accumulator of Co and Cu. P. nutans was a better accumulator of Co, Cu and Pb compared to bark.
The author investigated a 0-3 cm layer of two forest brown soils: brown acid and brown leached. These forest soils were under handsome beech trees (Fagus sp.) between 100 and 120 years old. The author compared the chemical properties of the soils. The soil existing near the tree trunk (1 m2 of surface, strongly washed by rain water polluted by chemical substances) and the soil existing under the tree umbrella (40 m2 of surface in the area of the tree-tops, washed poorly by rain water). This comparison showed changes in these properties, dependent upon the degree of atmospheric contamination. It was found that, at the same level of atmospheric contamination, higher changes of properties were found in brown leached soil than in brown acid soil. Less acidified soils (with alkaline or neutral pH reaction) are more suitable in these researches. The investigations of the forest soil layer 0-3 cm (12 soil profiles) showed that changes in their chemical properties in relation to tree trunk-tree umbrella can be the basis of assessment of the degree of atmospheric contamination.
Soot and hydrocarbons are usually found in diesel exhaust gases. They are formed when the fuel is burnt out incompletely. Polycyclic aromatic hydrocarbons (PAH) are sorbed on the soot, and may cause cancerous diseases, asthma and other diseases. The purpose of this work was to evaluate the dependence of smoke opacity and amount of polycyclic aromatic hydrocarbons in engine emissions on multi-component biodiesel fuel composition. We analyzed the composition of exhaust gases when diesel engine was fuelled with rapeseed oil methyl esters (RME ), RME mixtures with linseed oil methyl esters (LSME ) and fatty acid methyl esters (FA ME) of animal origin, assessing the smoke opacity and qualitative and quantitative composition of PAH. It was determined that smoke opacity of exhaust gases decreases at different rotation speeds (1200 and 2000 min⁻¹) when the amount of FA ME, containing a greater amount of saturated fatty acids, is increasing. Total PAH concentration in exhaust gases of biofuel mixtures with pork lard fatty acid methyl esters (LME ) is lower than in the case of mixtures with beef tallow fatty acid methyl esters (TME ). The amount of PAH at a rotation speed of 1200 min⁻¹ reduced down to 57%, if compared to pure RME , and down to 30%, when the rotation speed was 2000 min⁻¹. In the exhaust gases of biofuel mixtures with pork lard fatty acid methyl esters there are fewer PAHs with highly expressed mutagenic and carcinogenic effects if compared to pure RME and its mixtures, containing tallow fatty acid methyl esters. The most effective from an environmental point of view is use of a fuel mixture containing 80% RME , 4% LSME and 16% LME.
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