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Leonard Boszke Artur Kowalski Witold Szczuciński Grzegorz Rachlewicz Stanisław Lorenc Jerzy Siepak 《Environmental Geology》2006,51(4):527-536
The 26 December 2004 tsunami covered significant portion of a coastal zone with a blanket of potentially contaminated sediments. In this report are presented results on mercury concentrations in sediments deposited by the tsunami in a coastal zone of Thailand. Since the total mercury concentrations are insufficient to assess mercury mobility and bioavailability in sediment, its fractionation was applied. Sediments were sampled within 50 days after the event and analyzed by sequential extraction method. The procedure of sequential extraction involved five subsequent stages performed with solutions of chloroform, deionized water, 0.5 M HCl, 0.2 M NaOH, and aqua regia. The mean concentration of total mercury in sediments was 119 ± 50 ng g−1 dry mass (range 66–230). The fractionation revealed that mercury is mainly bound to the least bioavailable sulphides 75 ± 6% (range 62–86), organomercury compounds 14 ± 7% (range 4–26), and humic matter 9 ± 7% (range 1–27). The lowest contributions bring fractions of water-soluble mercury 0.8 ± 1.0% (range 0.1–3.6) and acid soluble mercury 0.9 ± 0.5% (range 0.2–2.1). Although, the total mercury content is similar in a reference sample and in the tsunami sediments, the highly toxic organomercury fraction contribution is higher in the latter. The results were compared with chemical and sedimentological properties of the sediments but no significant correlations were obtained between them. 相似文献
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By means of an integrated multifunctional experimental pilot plant there were tested several process variants for the treatment of carbonic-acid-aggressive and manganese-enriched model water. Deacidification and oxidation of iron- and manganese-constituents are effected by gas exchange with atmospheric oxygen. The hydrated-oxide particles formed are held back by two layers of foamed polyurethane and a sand bed lying uppermost. The process of neutralization and oxidation as well as flocculation is accelerated by the use of chalk, lime or soda. The effectiveness of the process technology investigated is illustrated by a table of results of small-scale experiments with model waters prepared from drinking water. 相似文献
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S. Mazevet M. Challacombe P. M. Kowalski D. Saumon 《Astrophysics and Space Science》2007,307(1-3):273-277
We investigate the conductivity of warm dense helium under conditions found in the atmospheres of cool white dwarfs using
ab initio simulations. The calculations performed consist of quantum molecular dynamics simulations where the electronic wavefunction
at each time step is obtained using density functional theory, while the ion trajectories are calculated using the resulting
quantum mechanical forces. We use both conventional DFT (PW91) and hybrid (PBE0) functionals to calculate the conductivities
that provide an estimate of the ionization fraction. While the calculations are in good agreement with the measurements for
the equation of state, a significant discrepancy exists with the recently measured conductivity. 相似文献
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Landslides - Landslide run-out modeling is a powerful model-based decision support tool for landslide hazard assessment and mitigation. Most landslide run-out models contain parameters that cannot... 相似文献
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M. Kowalski J. Wolany J. S. Pastuszka G. Płaza A. Wlazło K. Ulfig A. Malina 《International Journal of Environmental Science and Technology》2017,14(10):2181-2192
The aim of this study was to characterize both the viable airborne bacteria and fungi collected in different types of wastewater treatment plants in Poland. Bacterial and fungal aerosols in five different wastewater treatment plants in Poland were studied, including the pioneering antibiotic resistance testing of airborne bacteria. Concentration level was measured using the six-stage Andersen impactor. After incubation, bioaerosol particles captured on nutrient media on Petri dishes were quantitatively evaluated and qualitatively identified. It was found that the concentration levels of both airborne bacteria and fungi ranged from 10² to 10³ colony-forming units/m³, in all stages of the wastewater treatment plants. The patterns of size distributions of airborne bacteria and fungi were very similar, showing dominant peaks typically in the size range between 3.3 and 4.7 μm. The majority fraction of small bacterial and fungal particles (less than 4.7 μm) in the studied areas indicates that the bioaerosol is relatively fresh, and mostly of local origin. The Gram-positive cocci and nonsporing Gram-positive rods were the dominating forms in the studied wastewater treatment plants environment. The existing differences in the concentration levels between sampling sites enabled identification of the main bioaerosol sources. The highest concentration of bacterial aerosol appeared in sections, where activated sludge post-processing and mechanical purifying are conducted. The most frequently occurring species in the sampled bacterial aerosol were Gram-positive cocci and nonsporing Gram-positive rods. Multi-antibiotic resistance testing showed that among the isolated airborne bacteria, the most antibiotic-resistant features were present among Bacillus species (especially Bacillus mycoides). 相似文献
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Kowalski Andrew S. Serrano-Ortiz Penélope Miranda-García Gabriela Fratini Gerardo 《Boundary-Layer Meteorology》2021,179(3):347-367
Boundary-Layer Meteorology - An analysis based on the law of linear momentum conservation demonstrates unequivocally that the mass fraction is the scalar whose gradient determines gas diffusion,... 相似文献
8.
Agnieszka Generowicz Zygmunt Kowalski Joanna Kulczycka Agnieszka Makara 《洁净——土壤、空气、水》2011,39(7):688-696
The proposal of application of multi‐criteria analysis and technological quality method for optimization of technological processes on the case study of sodium chromate production variants from waste was presented. The research on the use of chromic waste for the production of sodium chromate made it possible to determine the optimal process parameters. Technological quality method was used to define the value of criterions for multi‐criteria analysis while multi‐criteria analysis allowed determining the impact of criterions weights for ranking variants of technological process. Both methods in a complex way evaluate the degree of modernization of technologies, describing them qualitatively within the area of environmental, technical, and the economic effects of the proposed technological variants. Based on the proposed evaluating criteria both methods yield comparable results. The most advantageous alternatives provided realization of the sodium chromate production process with the use of in‐process recycling of chromic mud, off‐site recycling of chromic tannery waste and on‐site recycling of waste from the old chromic heaps. 相似文献
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Rocky habitats are regarded as biodiversity hot-spots.Along with high species diversity,diverse ecological relationships can be observed in these habitats.Large groups of bird species use rocks in various ways:as perching/roosting sites,breeding or foraging habitats,information exchange sites,display arenas or as sources of minerals and water.Because of the inaccessibility of these environments,their role and importance to animals has been underestimated.We evaluated the use of rocky habitats by birds in the Tatra Mountains(49°13'N,19°57'E,Carpathians,central Europe).Rocky habitats were used by 29 bird species,eight of which used cliffs directly(i.e.for nesting,foraging or resting).The number of species recorded as using cliffs was correlated with the surface area of the cliff face.A total of 20 forms of rocky habitat use were recorded,in five behavioural categories:vocalization,foraging,perching,flight and nesting.Prevailing behaviours were flying by a rock face,circling above the face,and vocalization on a tree/shrub growing next to a rock.Rocks provide a nesting habitat for specialized petrophilic species and permit the existence of numerous ecological relations between species and habitats.The results of this study show that rocky habitats support the diversity of ecological relationships. 相似文献