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81.
Environmental Science and Pollution Research - Phytoremediation, as a cost-effective, highly efficient, environmentally friendly, and green approach, gained attention to the removal of metals,...  相似文献   
82.
Fifteen species of wild mushrooms and underlying soil samples collected in a virgin landscape of Augustowska Forest in northeastern Poland in 1997-98 were analyzed for total mercury to evaluate the status of contamination and usefulness of higher mushrooms as possible bioindicators of mercury pollution. Among the 15 species analyzed, Pinewood King Bolete, Scaly Tooth and King Bolete showed relatively high bioconcentration factors (BCF: dry-weight normalized concentrations of mercury in mushrooms relative to concentrations in soil) for mercury, which varied between 69 and 110. These three species were also characterized by great concentrations of total mercury in caps (between 2,000 +/- 800 and 2,300 +/- 1,100 ng g-1 dry wt) and stalks (between 850 +/- 390 and 1,000 +/- 500 ng g-1 dry wt.). Species such as Red-hot Milk Cap, Poison Pax and Common Chantherelle had mercury BCFs of less than 1, while Gipsy Bolete, Orange Birch Bolete, Brown Scaber Stalk, Variegated Bolete, Sandy Knight-cap and Yellow-cracking Bolete were weak or moderate mercury accumulators with BCFs between 1 and 40. Concentrations of mercury in mushrooms were greater than the tolerance limits suggested for mercury in plant foods.  相似文献   
83.
The insulation material of electronic devices should offers high thermal conductivity whilst retaining suitable mechanical properties. Epoxy resin is an example of a material that is commonly used by industry for electronic insulation, despite the fact that neither the thermal conductivity nor the mechanical properties are particularly satisfying. These properties can be enhanced by incorporating filler, with silica flour representing the most popular filler. An economically appealing solution is to replace silica flour with fly ash as filler material, however it must be remembered that compatibility of fly ash and epoxy resin is not ideal. In order to improve the coupling between these two materials, fly ash particles covered with [3-(2-Aminoethylamino)propyl]trimethoxysilane were obtained with six different conditions of the silanization process, where the amount of silane, the temperature and the time of the reaction were changed. The presence of the silane layer was confirmed via Fourier Transform Infrared Spectroscopy, Thermogravimetric Analysis and Scanning Electron Microscopy. The mechanical properties, including tensile strength, Young Modulus and fracture toughness, as well as the thermal conductivity of the final samples were investigated. In the case of composites with silanized fillers, all of the mechanical properties were improved, and an enhancement of thermal conductivity was observed for several composites. Moreover, the differences in coupling between the silanized fly ash and the untreated fly ash, and the epoxy matrix were precisely recorded by means of SEM. The presented studies confirm that an effective silanization process can significantly improve the properties of composites, while also verifying the usefulness of waste material. The results highlight that fly ash may be utilized to create a more economically affordable insulation material.  相似文献   
84.
Although shell colour polymorphism of the land snail Cepaea nemoralis is a well-known phenomenon, proximate and ultimate factors driving its evolution remain uncertain. Polymorphic species show variation in behavioural responses to selective forces. Therefore, we estimated effects of various environmental factors (temperature, humidity, food availability, (micro)habitat structure and predatory pressure) on behavioural response (frequency of locomotion, climbing and hiding) of C. nemoralis morphs, in experimental and natural conditions. In the experimental part of study, the frequency of locomotion was negatively affected by temperature and the presence of food and positively influenced by the presence of light. Morphs significantly differed in behavioural responses to environmental variability. Pink mid-banded and yellow five-banded morphs climbed less often and hide in shelter more often than yellow and pink unbanded individuals when temperature was low and food was absent. Snails fed most often at moderate temperature compared to low and high temperatures. Field investigations partially confirmed differences among morphs in frequency of climbing, but not in terms of probability of hiding in sheltered sites. In natural colonies, temperature and (micro)habitat structure significantly affected frequency of climbing as well as hiding in shelter. Snails more often hid in sheltered sites where thrushes preyed on Cepaea. Tendency of unbanded morphs to climb trees may have evolved under avian predatory pressure as thrushes forage on a ground. Tendency of banded morphs to hide in sheltered sites may reflect prey preferences for cryptic background. The results implicate that differential behaviour of C. nemoralis morphs compensate for their morphological and physiological limitations of adaptation to habitat.  相似文献   
85.
The Science of Nature - One of the most spectacular evolutionary forces is predation, evidenced to stimulate polymorphism in many prey species. Shell colour polymorphism of the land snail Cepaea...  相似文献   
86.
Harbor sediments containing large deposits of organotin compounds constitute a potential threat to the marine environment. Samples of harbor sediments were collected twice in the years 2003 and 2005 from the following locations: Zió?kowskiego, Siarkowe, Wi?lane, Weglowe, Chemików and Paliw P?ynnych Quays. The cores of 25cm length sliced into 2- and 5-cm segments were analyzed. After drying and homogenization, samples were split into two granulometric fractions, i.e. <2.00 and <0.063mm. The dominant fraction in whole sediment, i.e. fraction grain diameter <2.00mm, was sand (grain diameter 2.00-0.063mm). However, the highest concentrations of butyltin (BT) and phenyltin (PT) compounds were found in the fine sediment fraction. The mean values of tributyltin (TBT), dibutyltin (DBT) and monobutyltin (MBT) in the analyzed samples in the <2.00mm fraction were 2144.9, 434.7 and 148.1ngSng(-1)d.w., respectively, while the corresponding mean values in the <0.063mm fraction were 6556.4, 1593.7 and 450.0ngSng(-1)d.w. The mean concentrations of monophenyltin (MPhT) have been estimated at 29.0 and 49.9ngSng(-1)d.w. for the <2.00 and <0.063mm fraction sizes, respectively. The estimated content levels of diphenyltin (DPhT) and triphenyltin (TPhT) were in most cases below the detection limit of the applied method. The sediment cores collected from the locations characterized by high industrialization and intense exploitation (Wi?lane, Weglowe Quays) contained the highest concentrations of BT and PT.  相似文献   
87.
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89.
Sulfonamides (SAs) are one of the oldest groups of veterinary chemotherapeutic agents. As these compounds are not completely metabolized in animals, a high proportion of the native form is excreted in feces and urine. They are therefore released either directly to the environment in aquacultures and by grazing animals, or indirectly during the application of manure or slurry. Once released into the environment, SAs become distributed among various environmental compartments and may be transported to surface or ground waters. The physicochemical properties of SAs, dosage and nature of the matrix are the factors mainly responsible for their distribution in the natural environment. Although these rather polar compounds have been in use for over half a century, knowledge of their fate and behavior in soil ecosystems is still limited. Therefore, in this work we have determined the sorption potential of sulfadimethoxine and sulfaguanidine on various natural soils. The influence on sorption of external factors, such as ionic strength and pH, were also determined. The sorption coefficients (Kd) obtained for the sulfonamides investigated were quite low (from 0.20 to 381.17 mL g−1 for sulfadimethoxine and from 0.39 to 35.09 mL g−1 for sulfaguanidine), which indicated that these substances are highly mobile and have the potential to run off into surface waters and/or infiltrate ground water. Moreover, the sorption of these pharmaceuticals was found to be influenced by OC, soil solution pH and ionic strength, with higher Kd values for soils of higher OC and lower Kd values with increasing pH and ionic strength.  相似文献   
90.
Rybak A  Messyasz B  Lęska B 《Chemosphere》2012,89(9):1066-1076
We analyzed the ability of freshwater taxa of the genus Ulva (Ulvaceae, Chlorophyta) to serve as bioindicators of metal in lakes and rivers. Changes in heavy metal (Ni, Cd and Pb) and alkaline earth metal (Ca and Mg) concentrations in freshwater Ulva thalli were investigated during the period from June to August 2010. The study was conducted in two ecosystems in Western Poland, the Malta lake (10 sites) and the Nielba river (six sites). Three components were collected for each sample, including water, sediment and Ulva thalli. The average concentrations of metals in the water sample and in the macroalgae decreased in the following order: Ca > Mg > Ni > Pb > Cd. The sediment revealed a slightly altered order: Ca > Mg > Pb > Ni > Cd. Ca and Mg were found at the highest concentrations in thalli due to the presence of carbonate on its surface. Among the examined heavy metals in thalli, Ni was in the highest concentration, and Cd found in the lowest concentration. There were statistically significant correlations between the levels of metals in macroalgae, water and sediment. Freshwater populations of Ulva exhibited a greater efficiency to bioaccumulate nickel as compared to species derived from marine ecosystems.  相似文献   
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