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The preliminary studies of Al2O3 – BaO catalyst for storage and reduction of NOx in exhaust gases at rich and lean fuel mixture were performed. The conversions of nitrogen oxides as a function of fuel mixture composition were determined.
Economic and environmental aspects of generating energy from renewable sources in various forms: thermal, electric and mechanical have been presented in this article. Utilization of those resources and their promotion has been imposed on us by the climate convention but substantial level of pollution in large cities of our country contributed to that as well. RES share in the production of electricity and heating in Poland is regulated centrally by the directive of Minister of Economy. RES utilization is gradually becoming more rational in our country. It levels the prices of biomass for energy sector which has a visible impact on the level of round wood prices in Poland.
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The paper presents the main natural and anthropogenic sources of sulfur compounds, the proportion of these compounds in natural fuels and their emission to the aerosphere. Particular attention was paid to conditions of photochemical and catalytic oxidation in the air, as well as the behavior of sulfur compounds in the aerosphere. The transformations of sulfur compounds and their reactions with other compounds or elements contribute to air pollution, including the formation of tropospheric ozone and acid rains.
The paper presents the results of a study on the impact of the cultivation of crops which may serve as a substrate for a biogas plant on the atmosphere. Subjects addressed in the study cover a range of issues related to greenhouse gas (GHG) emissions from this area of agricultural activity. The amounts of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) emitted to the atmosphere in the selected cultivation technologies of beet, maize for silage and grasses were calculated. Emissions of GHG from chemical fertiliser production corresponding to the quantities used in the individual technologies were analysed, and amounts of the emitted above-mentioned pollutants originating from diesel fuel used during agricultural treatments conducted with the use of agricultural machinery were calculated. Emission values were expressed in equivalent units – E CO2eq. The study demonstrated that technologies which result in the highest quantities of emission are maize cultivation technologies – the average value for the study crops is 1 428 490.56 g haˉ¹ CO2eq. The lowest level of pollutants in the form of emitted greenhouse gases originates from grass cultivation and its average value is 904 661.28 g haˉ¹ CO2eq.
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Methane in the environment (a review)

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The atmospheric concentration of methane, a potential greenhouse gas, is determined by global balance between sources and sinks. The aim of the paper was to review the recent studies on the natural and anthropogenic sources that are responsible for the increase in the concentration of methane in the atmosphere, focusing on processes of methane formation and oxidation and factors influencing them. Methanotrophic and methanogenic metabolisms are an important part of these researches from the viewpoint of environmental protection. Great variability of soil properties and their interactions affecting the production, consumption and transport of CH4 makes our understanding of these processes still insufficient. Although most research to date has focused on sources of methane emissions, CH4 absorption by oxygenated soil is an important process that significantly reduces emission. The paper describes many soil-related factors affecting methanotrophic activity: particle size distribution, humidity, temperature, pH, oxygen concentration, use of nitrogen fertilisers. Land use has a significant effect on CH4 oxidation in soils, the greatest methnotrophic potential being that of forest soils as compared to meadows, pastures and arable land.
The main microclimate parameters, i.e. bacterial count and airborne emission to the immediate environment, were analyzed in a dairy barn. Air temperature, relative humidity and air flow velocity were measured on an attested Testo 400 device (Testo Inc., Germany). Air samples were collected by use of a Merck MAS-100 device (Merck KgaA, Darmstadt, Germany) onto a commercially available nutrient Columbia agar (Biolife, Milan, Italy) and incubated for 24 h in an incubator at 37oC work temperature. Measurements were carried out once a week in the morning, at noon, and in the evening during October and November 2002. In the barn, measurements were performed in the animal housing area along the feedlot, and outside the barn at a distance of 5 m, 25 m and 50 m eastward and westward from the barn. The measured dairy barn temperature ranged from 11.2oC to 13.1oC, relative humidity from 71.3-78.6%, and air flow velocity from 0.09-0.11 m/s. The mean value of total bacterial count in the barn air ranged from 2.82 x 104 cfu/m3 at noon to 7.76 x 104 cfu/m3 in the evening. Bacterial count decreased at particular measuring sites outside the barn, with Wilcoxon matched pair test showing statistical significance (p<0.05) at a distance of 5 m eastward and 5 m westward of the barn.
The number of orientation, feeding and social calls emitted by pipistrelle batsPipistrellus pipistrellus Schreber, 1774 andP. pygmaeus Leach, 1825 was recorded throughout the night at eight different sites. Social calls were unaffected by weather variables, whereas orientation calls and feeding buzzes were both significantly affected by cloud and temperature conditions. The number of emissions of each call type was significantly different between sites, indicating that the bats used different sites for different activities. Significant positive correlations between all three combinations of call types occurred only during the middle of the night, corresponding with the nadir of flying insects. This suggests that bats were engaged in activities other than feeding at this time, such as territory protection or mate attraction.
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