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The capacity of functional groups of soil organic matter to form organometallic complexes may efficiently reduce the risk of migration of toxic ions of heavy metals in the environment. Therefore, a research was conducted to determine the effect of composting and pyrolysis of Miscanthus giganteus biomass on the quality of humic compounds and on the ability of these materials to bind cadmium ions from the solution. Both processes did not cause any significantly favorable changes in fractional composition of the humic compounds of the transformed Miscanthus giganteus biomass. In the case of the unprocessed and composted biomass, changes in cadmium sorption by the materials used in the research, depending on Cd dose and how long the sample was in contact with the solution, had a similar course, which indicates that the responses taking place directly after the application of the solution that contained Cd ions were stable. In the case of thermal processing of Miscanthus giganteus biomass, it was found that Cd content in the solution decreased with time. Lower cadmium concentrations in the extracts after separation of the biomass were determined in the series with biologically transformed Miscanthus giganteus.
The possibility of using the monoionic Ag+ - form of clinoptilolite of domestic origin for radioactive iodide separation from waters has heen studied. The capacity of the silver form of clinoptilolite towards iodide exceeds many times that of the capacity of clinoptilolite in natural form. Due to low solubility the product Agl iodides generate precipitates on the surface of zeolite. SEM and rtg analyses of the silver form of clinoptilolite after sorption of iodide demonstrate the formation of new crystals on the zeolite surface. In comparison to the origin clinoptilolite sample, TG - analyses show that maximum water release occurs earlier. Sorption of iodide on the silver form of clinoptilolite was described as a second order reaction. The influence of interfering anions on the adsorption capacity of silver clinoptilolite towards iodide was also investigated.
In the initial phase of growth in an oligo-humotrophic lake, Cladium mariscus forms a dense and tall sawgrass bed invading the open water in the form of a floating mat. High densities of submerged evergreen perennial stems of C. mariscus, over two metres high and abundantly fruiting, ensure its persistence, and form a natural barrier to the invasion of other species. Dense mats of sawgrass are formed as a result of clonal and rhizome growth. Although diaspore production is abundant under natural conditions, only vegetative propagation of stems was observed. In different variants of the experiment only seeds wintering on stems of mother plants were capable of germinating. Hard seed coats had an important effect on the germination capacity of seeds.
The aim of this study was to investigate the effect of peroxisome proliferator activated receptors alpha agonist, fenofibrate, on the level of oxidative stress, total antioxidant capacity, and plasma paraoxonase 1 (PON1) activity in the rat. The adult male Wistar rats received fenofibrate for 7 days. The drug was added to food at concentrations 0.005%, 0.05% and 0.5%, which corresponded to doses of 3, 30 and 300 mg/kg/day, respectively. Fenofibrate treatment dose-dependently reduced plasma concentration of malonyldialdehyde and 4-hydroxydialkenals. The level of these lipid peroxidation products in animals treated with 0.005%, 0.05% and 0.5% fenofibrate was lower than in control group by 52.8%, 62.7% and 87.1%, respectively. Lipid hydroperoxides in plasma decreased by 29.7%, 23.4% and 27.5% in these groups, respectively. The drug had no significant effect on total antioxidant capacity measured as ferric reducing ability of plasma (FRAP). Paraoxon-hydrolyzing activity (PON) of plasma paraoxonase was 81.5% lower in animals receiving 0.05% fenofibrate and 69.2% lower in rats treated with 0.5% fenofibrate than in control. Phenyl acetate hydrolyzing activity (arylesterase, AE) was reduced by 15.2%, 49.6% and 55.8% in rats receiving 0.005%, 0.05% and 0.5% fenofibrate, respectively. PON/AE ratio decreased following 0.05% and 0.5% fenofibrate by 64.9% and 30.4%, respectively. The drug had no significant effect on total plasma triglycerides and cholesterol concentrations. The results indicate that fenofibrate treatment favourably modulates oxidant-antioxidant balance and unfavourably affects plasma PON1 activity in normolipidemic rats. These effects can contribute to the influence of PPARalpha agonists on pathological processes involved in atherogenesis.
Ecohydrology has the potential to make a significant contribution to the global need for improved water resources management. An investigation was conducted into educational and capacity building activities related to ecohydrology in an effort to better integrate understanding, promote awareness of existing activities, and to recommend action for global knowledge translation. Based on a survey of key partners and a review of the literature, three key observations were made: 1) consistency in the use of the definition and key concepts behind ecohydrology must be achieved, 2) development of a framework for courses in ecohydrology be developed for application on a regional and global scale and 3) there may be existing educational materials on ecohydrology but they are not well publicized or accessible even to seasoned practitioners. These recommendations are currently being implemented with the development and testing of three pilot courses.
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