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21.
Pore waters play an important role in phosphorus dynamics in aquatic ecosystems. Phosphorus concentrations in pore waters
are much higher than above the bottom. This is confirmed by the results of this study concerning the hypereutrophic lake.
Pore water was analyzed at 11 sampling stations in the upper layer of bottom sediments. This water was separated by centrifugation
and phosphorus level was measured spectrophotometrically with ascorbic acid as a reducer. Total phosphorus concentration in
pore waters ranged from 0.5 to 8.1 mgP l − 1 (mean 3.2 mgP l − 1). Mean phosphorus concentration in pore water samples of this lake was the highest in summer and the lowest in winter. High
concentrations were observed in samples from the pelagial and low from the macrophyte zone. 相似文献
22.
Danuta Barałkiewicz Maria Chudzińska Barbara Szpakowska Dariusz Świerk Ryszard Gołdyn Renata Dondajewska 《Environmental monitoring and assessment》2014,186(10):6789-6803
We studied the effect of storm water drained by the sewerage system and discharged into a river and a small reservoir, on the example of five catchments located within the boundaries of the city of Poznań (Poland). These catchments differed both in terms of their surface area and land use (single- and multi-family housing, industrial areas). The aim of the analyses was to explain to what extent pollutants found in storm water runoff from the studied catchments affected the quality of surface waters and whether it threatened the aquatic organisms. Only some of the 14 studied variables and 22 chemical elements were important for the water quality of the river, i.e., pH, TSS, rain intensity, temperature, conductivity, dissolved oxygen, organic matter content, Al, Cu, Pb, Zn, Fe, Cd, Ni, Se, and Tl. The most serious threat to biota in the receiver came from the copper contamination of storm water runoff. Of all samples below the sewerage outflow, 74 % exceeded the mean acute value for Daphnia species. Some of them exceeded safe concentrations for other aquatic organisms. Only the outlet from the industrial area with the highest impervious surface had a substantial influence on the water quality of the river. A reservoir situated in the river course had an important influence on the elimination of storm water pollution, despite the very short residence time of its water. 相似文献
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24.
Ryszard Korycki 《International journal of occupational safety and ergonomics》2013,19(4):423-448
The goal of theoretical research is to establish parameters, which have to be given in standards for percussive tests of products. Those parameters are essential for each user to be able to construct identical (equivalent) testing equipment. This would ensure identical results for identical products.The paper presents a detailed analysis of the distribution and the value of the forces generated during percussive collisions of two bodies. Elastic, plastic, and elastoplastic collisions are considered. Parameters determining the coefficient of restitution, the courses of energy, momenta, and the values of the forces in colliding elements are determined. The dynamic force acting on a product during a percussive test was studied. 相似文献
25.
Chaetoceros dichaeta Ehrenberg is one of the most important planktonic diatom species in the Southern Ocean, making a significant contribution
to the total biomass in the region. Our observations on both field and culture material have revealed the existence of a specialized
form of C. dichaeta adapted to living in sea ice. This sea ice form differs from the planktonic form by the shape and orientation of the setae
and the aperture length between sibling cells. Thus, the diameter of the chain is equivalent to the apical axes of the cells
and is accompanied by a two order of magnitude decrease in minimal space requirement. Here, we report for the first time on
the extraordinary overwintering strategy of a planktonic diatom in sea ice facilitated by its rapid morphological adaptation
to changing environmental conditions. This morphological plasticity enables it to thrive in the confined space of the sea
ice brine matrix and retain its numerical dominance in recurrent growing seasons and has likely evolved to optimally exploit
the dynamic ecosystem of the seasonally ice-covered seas of the Southern Ocean. 相似文献
26.
Korycki Michał Łobocki Lech Wyszogrodzki Andrzej 《Environmental Fluid Mechanics》2016,16(6):1143-1171
Environmental Fluid Mechanics - Results of large-eddy simulations of stably stratified atmospheric flow around an isolated, complex-shaped tall building are presented. The study focuses on the... 相似文献
27.
Victor Cucarella Ryszard Mazurek Micha? Kope? 《Environmental pollution (Barking, Essex : 1987)》2009,157(7):2147-2152
Reactive filter materials used for phosphorus (P) removal from wastewater can be disposed of as soil amendments after treatment, thus recycling P and other macro- and micro-nutrients to plants. In addition, materials with a high pH and Ca content, such as Polonite, are potential soil conditioners, which can be particularly beneficial for acid soils. Polonite previously used for on-site wastewater treatment was applied as a soil amendment to a mountain meadow. The amendment significantly increased soil pH and decreased the hydrolytic acidity, thus reducing Al toxicity risks. The effects were comparable to those of liming. No difference in yield and P uptake by meadow plants was observed. The uptake of metals was lower for amended soils, especially the uptake of Mn. Using Polonite after wastewater treatment as a soil amendment is thus a viable disposal alternative that can replace liming, when necessary, being capable of recycling P and other nutrients to meadow plants. 相似文献
28.
Kowalczewska-Madura Katarzyna Dondajewska Renata Gołdyn Ryszard Podsiadłowski Stanisław 《Environmental science and pollution research international》2017,24(16):14417-14429
Environmental Science and Pollution Research - Uzarzewskie Lake was a hypereutrophic, dimictic lake characterized by low water transparency, high chlorophyll-a concentration and intense... 相似文献
29.
The subject of this study was to develop a method of simultaneous determination of PCDDs/PCDFs and HCB in exhaust gases from industrial installations. Sampling to determine PCDDs/PCDFs was conducted using the method described in PN-EN 1948-1: 2006, where the sorption material is polyurethane foam (PUF). In order to simultaneously collect PCDDs/PCDFs and HCB and to avoid sorbent bed breakthrough, it was necessary to apply an additional polyurethane sorption layer. Twenty-seven samples of exhaust gases from various cement plants and 40 samples of exhaust gases from hospital and industrial waste incineration plants collected in 2009/2010 in the entire territory of Poland were examined. The average content of PCDDs/Fs in samples from cement plants amounted to 0.076 ng I-TEQ N m(-3) (range of 0.002-0.62 ng I-TEQ N m(-3)), while the average content of HCB amounted to 10 ng N m(-3) (range of 0.98-60.5 ng N m(-3)). In the case of samples collected from waste incineration plants, the average concentration of PCDDs/Fs was 0.39 ng I-TEQN m(-3) (range of 0.002-5.68 ng I-TEQ N m(-3)). In the case of HCB, the average concentration was 238 ng N m(-3) (range of 3.21-2500 ng N m(-3)). Also, the interdependence of the concentration of PCDDs/PCDFs and HCB was determined in the analysed samples, with the ranges of low and high content of PCDDs/PCDFs being examined separately. In all cases, the determined values of the r correlation coefficient were within the range of 0.7-1.0, which indicates a good correlation between the concentrations of PCDDs/PCDFs and HCB. 相似文献
30.
Teresa Banaszak Ryszard Miller Mieczyslaw Zembrzuski 《Journal of the Air & Waste Management Association (1995)》2013,63(12):1434-1438
Studies of the thermal oxidation of waste gases were carried out in two variants. During the first, the destruction of waste gases was facilitated by hydrogen flame-generated radicals. During the other variant, this flame was not used, but the same temperature was maintained as in the first one. The waste gases used were mixtures of toluene with air and methane with air of 200 and 400 ppm concentrations, respectively. The experiments were performed in a flow reactor within the temperature range of 800 to 1330 K. The efficiency of oxidation of methane and toluene obtained during the first variant was considerably higher than that obtained in the second one. This was due to the promotional effect of the hydrogen flame. 相似文献