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Self-organizing feature map (neural networks) as a tool to select the best indicator of road traffic pollution (soil, leaves or bark of Robinia pseudoacacia L.)
2009
Samecka-Cymerman, A. | Stankiewicz, A. | Kolon, K. | Kempers, A.J.
Concentrations of the elements Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn were measured in the leaves and bark of Robinia pseudoacacia and the soil in which it grew, in the town of Oleśnica (SW Poland) and at a control site. We selected this town because emission from motor vehicles is practically the only source of air pollution, and it seemed interesting to evaluate its influence on soil and plants. The self-organizing feature map (SOFM) yielded distinct groups of soils and R. pseudoacacia leaves and bark, depending on traffic intensity. Only the map classifying bark samples identified an additional group of highly polluted sites along the main highway from Wrocław to Warszawa. The bark of R. pseudoacacia seems to be a better bioindicator of long-term cumulative traffic pollution in the investigated area, while leaves are good indicators of short-term seasonal accumulation trends. Once trained, SOFM could be used in the future to recognize types of pollution.
اظهر المزيد [+] اقل [-]Removal of Cu++ ions from aqueous solution by bisorbent based on Lagenaria vulgaris shell | Uklanjanje Cu++ jona iz vodenih rastvora biosorbentom na bazi kore Lagenaria vulgaris
2009
Bojic, A., Univerzitet u Nisu, Nis (Serbia). Prirodno-matematicki fakultet, Odsek za hemiju | Mitic-Stojanovic, D.L., JP Vodovod, Vranje (Serbia) | Bojic, d., Univerzitet u Nisu, Nis (Serbia). Prirodno-matematicki fakultet, Odsek za hemiju | Andjelkovic, T., Univerzitet u Nisu, Nis (Serbia). Prirodno-matematicki fakultet, Odsek za hemiju
This study investigates the effect of pH, temperature, contact time and initial metal concentration on Cu++ ions removal from water solutions, using biomass of Lagenaria vulgaris skin (LV). With higher pH, the efficiency of copper sorption increases and reaches its maximum at pH 7.0. Temperature has negative effect on sorption process due to its exothermic properties. Biosorption efficiency increases with time and reaches equilibium after 40 min. Increasing initial copper concentration gives an increase in biosorbent sorption capacity, and a proportional decrease in treatment efficiency. Obtained results have shown that LV based biosorbent is an efficient and available mean for toxic metal removal from natural and waste waters.
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