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Air protection technologies generate massive amounts of solid wastes, including fly ash (FA). Zeolite synthesis from FA seems to be an effective method for FA utilization. In addition, fly ash zeolites (FAZs) could be used for sulfur dioxide (SO2) adsorption. Since there is a lack of sufficient information about SO2 uptake on FAZs, we investigated this phenomenon in detail. Two commercially available zeolites, 3A and SM-27, and two FAZs, one manufactured by the authors and the other obtained from Kimura Chemical Plants, were used for SO2 adsorption tests. Our experiments confirmed that FAZs could be efficient SO2 adsorbents. Observed SO2–zero emission periods varied from 2-3 min for non-activated zeolites to 7-15 min for their thermally activated counterparts. The thermal activation of FAZs increased 2-3 times their SO2 adsorption capacity, resulting in up to 38 mg of SO2/g of zeolitic material.
It has been found that a suspension of ilmenite in water can be used as absorption medium in a gas desulphurization process. The degree of S02 absorption depends on S02 concentration, on the 02:S02 ratio in the gas, on temperature, and on ilmenite content in the suspension.
Under light stress of 1000 /imol s-1m-2 (λ=400 - 700 nm) for 140 min cyanobacteria mats of "tintenstrich" formations on limestone rocks of Kobylaňska-Valley, west of Cracow, Poland showed reduction of the potential and eiTective quantum yield variables ∆F/Fm' and Fv/Fm3, respectively of PSII and the samples first recovered partly after six days. Also, the Fo level, known to be affected by environmental stress, increased rapidly due to strong light intensity. Sulphite stress (100 mM) was first manifested very clearly after a long, 15h exposure, but not during the first 40 min. Thus, these terrestrial cyanobacteria appear to be less sensitive to sulphite stress than eucaryotic algae, lichens and higher plants studied so far. It is not yet clear if this is due to i) special adaptation of these free living terrestrial cyanobacteria growing in a heavily polluted area, ii) buffering capacity of the limestone support, or iii) other factors.
The immunological effects of environmental and/or occupational exposure to S02 in air as polluting gas have been examined in a group of 21 exposed men. The determination of S02 concentrations in ambient air in the work enviroment as well as in ambient air in residential areas of these men was performed, always using Amaya-Sugiura passive sampling and ion spectrophotometry. Mean concentration of S02 in ambient air in residential areas was 0.5792 mg • m-3 ± 0.2871 (0.22 to 1.52). Mean concentration of S02 in ambient air in the work enviroment was 2.2612 ± 2.1477 mg • m-3 (0.47 to 9.57). For the determination of T-cells and (CD19+)B-cell populations Behring monoclonal antibodies were used in indirect immunofluorescence tests. The serum levels of immunoglobulins: G, A, M, E; C3c and C4 complement components; total circulating immune complexes (CIC) as well as acute phase proteins: C-reactive protein (CRP), haptoglobin, ceruloplasmin and transferrin were determined by nephelometry. The mean number of total lymphocytes in men exposed to S02 was increased by 43% (p < 0.001). The stimulation T-cell line exposed to S02 was evidenced by increased number of (CD3+)T-cells, by about twice (p < 0.001) increased number of (CD4+)T-helper cells and by 68% (p < 0.001) increased number of (CD8+)T-suppressor cells. The higher increase of (CD4+)T-helper cells compared to (CD8+)T-suppressor cells caused the increased value of the (CD4+)T-helper/(CD8+)T-suppressor ratio by about 25% (p < 0.01) in the subjects exposed to S02. In contrast, a decreased number of (CD16+)NK cells by about 38% (p < 0.001) in men exposed to S02 was also observed. No changes were observed in the number of (CD19+)B-cells, as well as in the (CD3+)T/(CD8+)T-suppressor ratio. In the group exposed to S02, elevation of IgG serum levels by 23.3% (p < 0.001) was evidenced, as well as a decrease of C3c by 15.6% (p < 0.001) and C4 by 30% (p < 0.001), whereas total CIC in the serum was elevateds in same conditions by about 74% (p < 0.001). No changes were observed in the serum levels of IgA, IgM, IgE, CRP, haptoglobin, ceruloplasmin and transferrin. Significant positive correlations Irl (0.51 to 0.57) were only between S02 concentrations in air and serum concentrations of total CIC. Moreover, significant negative correlations Irl between S02 concentrations in air and leucocytes (WBC), and the determined T-cells populations and (CD19+)B-cells also were observed. In conclusion, environmental exposure to S02 can enhance proinflammatory processes in degree of exposure dependent manner and also can change some parameters of cell-mediated immunity.
A new method of atmospheric sulphur dioxide determination based on the reaction of sulphite ions with triarylmethane dye on polymer film has been developed. The addition of sulphite to aqueous solutions of triarylmethane dyes causes bleaching of the dye by formation of the sulphite complex. On the polymer film different aspects of the reaction such as the type of polymer, polymer film thickness, and atmospheric sulphur dioxide concentration have been studied. It was found that the process of diffusion has great influence on the reaction rate. That is why the most important thing for optimizing reaction conditions is choosing the polymer and plasticizer.
An absorption process of S02 in the aqueous suspension of ilmenite has been found to be an efficient process of gas desulphurization. Practically, the complete absorption of S02 is possible at the appropriate selection of the principal process parameters: ilmenite content in the suspension, and temperature.
In this study, artificial neural networks are proposed to predict the concentrations of S02 and PM at two different stations in Zonguldak city, a major coastal mining area in Turkey. The established artificial neural network models involve meteorological parameters and historical data on observed S02, PM as input variables. The models are based on a three-layer neural network trained by a back-propagation algorithm. The models accurately measure the trend of SO2 and PM concentrations. The results obtained through the proposed models show that artificial neural networks can efficiently be used in the analysis and prediction of air quality.
Polluted air is a stress factor that contributes to the decline of urban trees. Air pollution may cause short-term (acute) damage, which is immediately visible and long-term (chronic) damage, which can lead to gradual tree decline. Long-term damage may predispose trees to other disorders. The impact of technogenic factors on the leaf’s anatomical structure of Acer negundo L. (Box elder) was studied. The thickness of the upper cuticle is increased when compared to those from an ecologically pure area. A change in the rate of mesophyll tissue is due to the enlargement of the palisade parenchyma. The thickness of lower epidermal cells is decreased. All changes of the leaf blade structure are significant and are in direction of increasing the xerophyte characteristics of the leaves. Box elder is native to much of temperate North America. This is a tree of lowlands and wet hardwood forests. As such, we can assume that the registered changes are adaptive responses of the tree to the contaminated environment and that the tree can be considered to be relatively tolerant.
Leaf blades of Norway maple (Acer platanoides L.), growing in heavily polluted industrial area have been studied for anatomical changes developed under the influence of the industrial contamination (with SO2, NxOx, Pb, As). The aim of the examination was to reveal the dynamics in the development of leaf blades and to trace the impact of the contaminated air on the leaf structure of Norway maple. The conducted study registered acceleration of the vegetative growth of the leaf blades that is manifested through approximately two weeks earlier appearance of leaves on the tree, faster linear growth and strengthened the xeromorphic traits in the leaf structure of the tree plants from the contaminated region. The observed changes are regarded as adaptation of the plant to the polluted environment, i.e. as tolerance.
During one vegetative season, the growth and the development of the leaf blades of Tatarian maple (Acer tataricum L.) from heavily polluted area has been studied. The region under investigation was contaminated mainly with SO2, NxOx, Pb, Zn, and Cu etc. The aim of the study was to compare the growth and the development of the leaf blades of Acer tataricum L. (Tatarian maple) from polluted field with those from non-polluted. Base on this to assess its tolerance to polluted conditions of the atmosphere, as well as to look for adaptive responses. The conducted study registered shorter time of the vegetative growth of the leaf blades in the commencement stages of the vegetative development. The leaves from polluted site had emergence approximately two weeks earlier compared with these from the control area. Faster linear growth of the leaf surfaces in the commencement stages of the development had been noted for the trees from polluted field. The spongy mesophyll had been reduced, as well as the common thickness of the leaf blades of the tree plants from the contaminated region. The observed changes are regarded as adaptation of the plant to the polluted environment, i.e. as tolerance.
Epiphytic lichen distribution and diversity were investigated in seven localities in the centre of Cracow (South Poland). Field studies were carried out in the years 2007–2009. A total of 39 species were recorded at 434 sites; 6 species are new to Cracow. Compared to previous surveys, the overall situation has generally improved, with higher lichen species richness and cover rate. The area of former ‘lichen desert’ in the city centre has disappeared and it has been colonized by SO2 sensitive macrolichen species. Dominance of nitrogen- and dust-tolerant species has been observed. The health of lichen thalli has improved and many young specimens were recorded in the study area. These changes follow air quality improvement, mainly the SO2 decline, during the last twenty years. Transport-related NOx and dust have become the main pollutants in the centre of Cracow. The recolonization process seems to be not completed yet and further improvement in lichen distribution and diversity is expected. Thus long-term biomonitoring is required.
The purpose of this study was to assess the influence of SO2 on photosynthetic apparatus and the level of total nonstructural carbohydrates (TNC) in developing and mature leaves of poplar (Populus deltoides). Photosynthetic apparatus was evaluated on the basis of fluorescence parameters (Fv/Fm, OPSII, qP and Rfd) and photosynthetic pigments (chlorophylls and carotenoids). Cuttings of poplar were exposed to 0.25 ppm of SO2 at 25°C and 200-300 mmol m-2s-1 PAR for 6 hours daily during 5 days in a fumigation chamber. The fumigation did not produce any significant differences in fluorescence parameters in neither developing nor mature leaves. In some mature leaves the concentration of pigments increased under the influence of SO2. Soluble carbohydrates decreased significantly both in developing and mature leaves and this was accompanied with an increase in starch accumulation. We suggest that Populus deltoides is a species tolerant to sulphur dioxide and the used SO2 dosage did not significantly impair the light reactions of photosynthesis, but it disturbed the accumulation of starch and the utilization of soluble carbohydrates in plants exposed to SO2.
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