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71.
The external loading of 14 lakes in the Wielkopolska National Park was calculated, including nitrogen and phosphorus loads from point, diffuse and dispersed sources, precipitation and recreation. The basic source of nitrogen and phosphorus for most lakes in the Park is the export of diffuse pollution from the catchment area. Only four lakes are contaminated by sewage, which accounts for 0.1–61.2% of total nutrient loading. Annual unit area loads of phosphorus and nitrogen estimated for each lake were 2–51 times higher than Vollenweider’s critical loading levels. Estimated mass loading and annual unit area loads of nutrients for each lake were compared with lake water quality, expressed as the trophic state index. Analysis of the physico‐geographical structure of the catchment area and natural resistance of lakes to external input of nutrients allowed us to assess the role of the catchment in the deterioration of water quality and to indicate the protective measures required. 相似文献
72.
Seet KY Vogel R Nieminen TA Knöner G Rubinsztein-Dunlop H Trau M Zvyagin AV 《Applied optics》2007,46(9):1554-1561
The refractive index of novel organosilica (nano/micro) material is determined using two methods. The first method is based on analysis of optical extinction efficiency of organosilica beads versus wavelength, which is obtained by a standard laboratory spectrometer. The second method relies on the measurable trapping potential of these beads in the focused light beam (laser tweezers). Polystyrene beads were used to test these methods, and the determined dispersion curves of refractive-index values have been found accurate. The refractive index of organosilica beads has been determined to range from 1.60 to 1.51 over the wavelength range of 300-1100 nm. 相似文献
73.
The design of a curb is straight forward. The curb itself provides a conveyance of stormwater, facilitating the movement of water and pollutants from the street into waterways. Pollutants such as sediment, nutrients from lawn fertilizers, bacteria, viruses, pesticides, metals, and petroleum byproducts accumulate on the road surface and are released during storm events, carried to storm drains, and deposited into waterways, often without treatment. Once pollutants enter the waterways they impact the ecosystem and affect water quality. How can discrete standards—like a curb—be leveraged to have larger systemic impacts? The redesign of the curb to perform as a magnet for pollutants can challenge this design standard. During the summer of 2019, the interdisciplinary research team tested alternatives to the standard concrete curb and apron at Ohio State University. The team used an iterative design process to add patterning and crenellations to the face of the curb and apron. Using full scale models to test simulated storm events, the team collected data to evaluate the performance of 21 alternative designs. The results suggest the new combined curb and apron designs can abstract pollutants from roadways before they are detrimental to water bodies and aquatic ecosystems. 相似文献
74.
S. Kment P. Kluson V. Stranak J. Krysa J. Pracharova M. Morozova Z. Hubicka 《Electrochimica acta》2009,54(12):3352-3359
Titanium(IV) oxide semiconducting thin films were deposited in the environment of chemically active plasma by means of the PVD hollow cathode plasma jet sputtering, PVD magnetron sputtering and the PECVD technique (surfatron produced plasma discharge as a jet type). In parallel the sol-gel process carried out in the reverse micelle environment was utilized as a purely chemical procedure. Prepared films were described by a series of characterization methods involving atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and ultraviolet-visible spectroscopy (UV-vis). All layers were tested then for their photo-induced electrochemical properties based on evaluation of polarization curves and corresponding photocurrents. These experiments were carried out in the opto-electrical apparatus supplemented with a system of highly precious spectral filters. The differences among photocurrent values were discussed. 相似文献
75.
76.
Wojciech Burakowski Andrzej Bęben Halina Tarasiuk Jarosław Śliwiński Robert Janowski Jordi Mongay Batalla Piotr Krawiec 《电信纪事》2008,63(11-12):559-577
In this paper, we present the framework to provision end-to-end QoS in heterogeneous multi-domain networks that was implemented in EuQoS system and tested in Pan-European research network. It assumes that a pair of end users, possibly attached to different access networks as xDSL, UMTS, LAN/Ethernet, WiFi, MPLS or Satellite, may choose for its connection an appropriate end-to-end Class of Service, depending on the application they use, e.g. VoIP, VoD, FTP, etc. Each end-to-end Class of Service has its own traffic control mechanisms and algorithms and, as a result, it has the ability to handle traffic streams with assumed guarantees for packet transfer characteristics expressed in the form of loss ratio, mean delay and delay variation. The end-to-end Classes of Service are supported in all the domains (including inter-domain links) independently using specialised inter-domain Class of Service-aware QoS routing protocol which establishes the end-to-end QoS paths. This paper describes the solution and includes exemplary simulation and experimental results. 相似文献
77.
Halina Kwasnicka Urszula Markowska-Kaczmar Marcin Mikosik 《Applied Soft Computing》2011,11(1):982-990
In this paper the FLOCK system is presented, which was designed to test the ability of simple genetic algorithm to evolve flocking behaviour in ecosystems consisting of plants, herbivores and predators. Open-ended evolution was applied in the experiments, first. Many different behaviours were observed, which were very similar to those in nature, for instance: the escape of herbivore from predators, making herbivores route towards plants or a pursuit of predators after herbivores. Another interesting behaviour was grouping of predators around plants, where the probability of meeting herbivores is greater than in other places. But open-ended evolution and complex vision system of animal were not sufficient to observe flocking behaviour. The advanced behaviour such as creation of flocks appeared as a result of steered evolution. 相似文献
78.
The aim of this study was to assess the influence of bioflavonoids from the radix of Scurellaria baicalensis on the level of lipids, via the determination of the concentrations of triglycerides, total cholesterol and high-density lipoprotein (HDL) cholesterol in the plasma of laboratory rats fed high-fat and high-cholesterol diets, and via the calculation of their atherogenic index. We also studied the influence of bioflavonoids on their physical development by measuring the increase in their body mass and liver mass. The rats were fed a diet with a 15% content of fresh or oxidized lard or sunflower oil, along with 0.5% added cholesterol. 0.05% S. baicalensis radix extract was added to the diet of half of the rats as the source of bioflavonoids. In the group of rats fed a diet containing oxidized oil we observed a significantly lower increase in body mass (15.5 +/- 7.6 g/4 weeks/rat) than that observed for the control rats (77.0 +/- 15.7 g/4 weeks/rat). The addition of S. baicalensis radix extract to the diet raised the increase in body mass in the groups receiving oil as the source of fat; those receiving fresh oil had a 40% increase, and those receiving oxidized oil showed a 300% increase relative to the appropriate controls. In all the groups of rats fed a diet with bioflavonoids added, a beneficial decrease in the plasma triglyceride content was observed relative to the appropriate controls. In the plasma of rats on a diet containing the extract and fresh or oxidized oil or fresh lard, we observed a beneficial reduction in the total cholesterol level relative to the appropriate controls. The atherogenic index was higher for the group of animals fed with fresh lard than for those fed with fresh oil, and higher for those fed with oxidized oil than for those fed with oxidized lard. The addition of bioflavonoids to the diet beneficially reduced the atherogenic index value in the group fed with fresh oil, and increased its value in the group fed with oxidized lard. 相似文献
79.
Zieliński H Michalska A Piskuła MK Kozłowska H 《Molecular nutrition & food research》2006,50(9):824-832
The seeds of buckwheat (Fagopyrum esculentum Moench L.) were dehulled and then, following milling, extruded on a counter rotating, twin-screw extruder with the different barrel temperature profiles: 120, 160, and 200 degrees C. After extrusion cooking process, the following compounds were analyzed: free and conjugated phenolic acids, total polyphenols (TPC), tocopherols (T) and tocotrienols (T3), inositol phosphates (IP), reduced glutathione (GSH), and melatonin (MLT). The antioxidant capacity and superoxide dismutase-like activity (SOD-like activity) were determined in the groats and extrudates. Extrusion caused a significant decrease in all the compounds tested, except for phenolic acids. The content of IP decreased by 13%, that of GSH by 42%, and that of T + T3 by 62%. A three-fold lower level of MLT and TPC was noted whereas the SOD-like activity disappeared when compared to the nonextruded material. A two-fold higher content of phenolic acids (free and released from ester bonds) was observed. In spite of the clear decrease in the investigated antioxidants, the extruded dehulled buckwheat seeds contained still significant content of bioactive compounds, which resulted in as little as an average 10% decrease of the antioxidant capacity. 相似文献
80.
Halina Kaczmarek 《Polymer Bulletin》1995,34(2):211-218
Summary Photooxidative degradation of cis 1,4-polybutadiene in diluted benzene solution and benzene/hydrogen peroxide emulsion have been examinated using viscosimetry, GPC, FTIR, UV-Vis spectrometry and iodometric titration. Efficient photooxidation and photodegradation of PB in presence of hydrogen peroxide was observed. The acceleration effect of photoprocesses in PB is caused by hydroxy (HO·) and hydroperoxide (HOO·) radicals. The mechanism of PB reactions with free radicals proceeding from hydrogen peroxide and influence of benzene on photodegradation of PB have been discussed. 相似文献