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In this paper, the contamination degree of the Rybnik Reservoir with cadmium, copper and nickel was analyzed. Quality of the water from the reservoir was determined by drawing comparisons between the metal content in the water and both the officially permitted levels (contamination factor) and levels of metals occurring in the water of non-contaminated areas (enrichment factor). Contamination of bottom sediment with chosen metals was analyzed with reference to the metal content in mudstone (geoaccumulation index, enrichment factor, contamination factor). Trends towards changing the metal content in the bottom sediment was analyzed by determining the enrichment factor of the surface layer of the bottom sediments in relation to a deeper layer. Enrichment of the bottom sediments with metals coming from the water was also determined.  相似文献   
2.
Forms of cadmium occurrence in the bottom sediment of a heated water reservoir, polluted substantially with this metal was analysed in the paper. Apart from the analysis mentioned above, a total cadmium content in the bottom sediment and a content of cadmium dissolved in the water of the reservoir was also determined. Dependences between particular forms of cadmium occurrence and its total content in the bottom sediment were analysed. An influence of cadmium content in water on the level of particular cadmium forms in the bottom sediment and an influence of other parameters of the reservoir's water on the content of cadmium in the bottom sediment were also examined.  相似文献   
3.
Total concentration of lead and its individual partitioning, i.e. exchangeable, adsorbed, organically bound, carbonate, sulfide and residual have been assayed in the bottom sediment of Rybnik reservoir applying AAS. The contribution of particular fractions to the total lead concentration was as follows: carbonates (37%) > sulfides (28%) > residual (14%) > adsorbed (10%) > exchangeable (8%) > organic bonds (3%). The multiple regression analysis applied led to the conclusion that the increase in lead content in the bottom sediment resulted from an increase in poorly mobile forms, notably carbonates.  相似文献   
4.
The adsorption process is one of the most important techniques of water and wastewater treatment technology. Therefore, there are many methods allowing to improve the effectiveness of these processes based mainly on the chemical modification of adsorbents. However, they are always associated with the necessity of introducing an additional wastes or sewage to the environment. That is why a purpose of the presented was to investigate an innovative and noninvasive adsorption supporting method based on the using of a static magnetic field. The results showed that in the adsorption process of equimolar copper, nickel, and cadmium mixture, a presence of the magnetic field may increase the effectiveness of the process, with respect to copper by more than 40% and a summary molar removal was increased about 11%. However, the effectiveness of the analyzed modification depends largely on the heavy metal equilibrium concentration, and when it increases, a beneficial effect of magnetic field significantly decreases. Nevertheless, due to the fact that heavy metal adsorption processes are very important part of environmental engineering technologies, it can be assumed that further work on magnetic modification of these processes can allow for a significant improvement of many water and wastewater purification plants.
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5.
Biosorbents are the natural origin adsorbents, which popularity in environmental engineering is steadily increasing due to their low price, ease of acquisition, and lack of the toxic properties. Presented research aimed to analyze the possibility of chemical modification of the straw, which is a characteristic waste in the Polish agriculture, to improve its biosorption properties with respect to removal of selected metals from aquatic solutions. Biosorbents used during the tests was a barley straw that was shredded to a size in the range of 0.2–1.0 mm. The biosorption process was performed for aqueous solutions of zinc at a pH 5. Two different modifications of straw were analyzed: esterification with methanol and modification using the citric acid at elevated temperature. The results, obtained during the research, show a clear improvement in sorption capacity of the straw modified by the citric acid. In the case of straw modified with methanol, it has been shown that the effectiveness of zinc biosorption process was even a twice lower with respect to the unmodified straw. Moreover, it was concluded that the removal of analyzed metals was based mainly on the ion-exchange adsorption mechanism by releasing a calcium and magnesium ions from the straw surface to the solution.
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