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Abstract  

The paper gives a short overview of application of polymer inclusion membranes (PIMs) for separation and removal of metal ions. Investigation of the selective removal of toxic metal ions, i.e. Cr(VI), Cd(II), Zn(II) from acidic chloride aqueous solutions, as well as trace radionuclides, i.e., 137Cs, 90Sr and 60Co from wastewaters using transport across polymer inclusion membranes was studied. The carriers, i.e., tri-n-octylamine for anionic metal species, as well as dibenzo-21-crown-7, tertbutyl-dibenzo-21-crown-7, and dinonylnaphtalenesulfonic acid for metal cations were incorporated into polymer inclusion membranes composed of cellulose triacetate as a support and o-nitrophenyl pentyl ether as a plasticizer. Selective transport of chromium(VI) over zinc(II) and cadmium(II) chloride complexes through PIMs was observed. Competitive transport of trace radionuclide ions, i.e., 137Cs, 90Sr, and 60Co from NaNO3 aqueous solutions across polymer inclusion membranes containing a mixture of dinonylnaphtalenesulfonic acid, and dibenzo-21-crown-7 as the carrier provide the selectivity order Cs(I)>Sr(II)>Co(II).

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A stabilizálószerek jelentősen különböznek egymástól. Mivel eddig ritkán került sor modellkísérletes vizsgálatukra, nagyon kevés adat áll rendelkezésre hatásmechanizmusaikról, tényleges hatékonyságukról. Talajinkubációs modellkísérletet állítottunk be 2007-ben az MTA Talajtani és Agrokémiai Kutatóintézetében. Az alkalmazott kémiai stabilizálószerek (különféle olcsó, nagy mennyiségben rendelkezésre álló hulladékok), a következők voltak: tatabányai erőművi pernye, csepeli és ráckevei ivóvíztisztításból származó vas-mangán csapadék. A kísérlet során alkalmazott modelltalajt a Gyöngyösorosziban található felhagyott színesfémérc bánya melletti Toka-patak öntésterületéről gyűjtöttük. A Zn, Pb, Cd, Cu, As valamint a Ba desztillált vizes, acetát pufferes, valamint Lakanen–Erviö-féle frakcióinak vizsgálatával értékeltük a különböző hulladékok stabilizáló hatását. A pernyének jó stabilizáló hatása volt a Cd, Cu, Pb és Zn fémre és nem mobilizálta az arzént és a báriumot sem. A ráckevei és a csepeli ivóvíztisztításból származó csapadékok ugyan nagyobb mértékben stabilizálták a Cd, Cu, Pb és a Zn fémeket, mint a pernye, de a mobilis As- és Ba-tartalmuk csökkentheti e speciális hulladékok ilyen jellegű hasznosíthatóságát. Ez alapján elmondható, hogy a tatabányai pernye alkalmasabb stabilizálószer, mint a ráckevei, vagy csepeli csapadék, de az erőművi pernye alkalmazásakor is rendkívül körültekintően kell eljárni, hiszen a nem megfelelő összetételű pernye használata (a toxikus fémek feldúsulhatnak), vagy a szakszerűtlen alkalmazás fokozhatja a talaj környezeti terhelését.

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Abstract  

The industrial pollution is exponentially growing in the developing countries due to the discharge of untreated effluents from the industries in the open atmosphere. This may cause severe health hazards in the general public. To reduce this effect, it is essential to remove the toxic and heavy metals from the effluents before their disposal into the biosphere. In this context, samples of the effluents were collected from the textile/yarn, ceramics and pulp/paper industries and the concentrations of the toxic metal ions were determined using neutron activation analysis (NAA) technique. The observed concentration values of the As, Cr and Fe ions, in the unprocessed industrial effluents, were 4.91 ± 0.8, 9.67 ± 0.7 and 9.71 ± 0.8 mg/L, respectively which was well above the standard recommended limits (i.e. 1.0, 1.0 and 2.0 mg/L, respectively). In order to remove the toxic metal ions from the effluents, the samples were treated with pea nut husk fence. After this treatment, 91.5% arsenic, 81.9% chromium and 66.5% iron metal ions were successfully removed from the effluents. Then the treated effluents contained concerned toxic metal ions concentrations within the permissible limits as recommended by the national environmental quality standards (NEQS).

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Abstract  

The bio-sorption of heavy and toxic radionuclides by three genera of algae from different taxonomic groups was studied employing the recently developed 'Tracer Packet' technique. The tracer packet of heavy and toxic metals' contained 197Hg, 198,199,200,201Tl, 199,200,201Pb, 204Bi and 204,205Po radionuclides in carrier-free state and was produced by irradiating a gold metal foil with medium energy 7Li and 12C beams successively in a 12 MV Pelletron. Three genera, Spirulina from Cyanophyceae, Oedogonium from Chlorophyceae and Catenella from Rhodophyceae were cultured in laboratory condition and were used in the experiment. The radionuclide accumulation varied according to different genera at different pH levels. At basic pH Spirulina showed a maximum radionuclide accumulation in comparison to other genera.

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Abstract  

The indiscriminate discharge of untreated industrial effluents and solid wastes into the open environment poses a serious threat to the ecosystem. Gujranwala is an industrial city of Pakistan wherein a large number of different industries are situated and majority of them are not equipped with proper recycling or effluent treatment plants. Unfortunately, untreated industrial effluents are locally used for the irrigation purposes which may result in higher concentrations of toxic metals in the crops and vegetables. Therefore, prime objective of the present study was to determine concentrations of toxic metals in the polluted soils, vegetables and crops grown in the vicinity of industrial areas using neutron activation analysis technique. The results obtained showed higher values of toxic metals in the studied samples. The observed highest concentration of As (0.94 ± 0.06) in spinach, Br (69 ± 9) in turnip, Co (0.83 ± 0.01) in millet, Cr (51.7 ± 4.2) in wheat, Mn (76.2 ± 7.3) in tomato, Sb (0.5 ± 0.06) in rice, Cl (31698 ± 3921) and Se (3.4 ± 0.4) in carrot. These values are higher than those reported in the literature.

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Abstract  

Air particulate samples taken downwind of two Toronto hospital incinerators analyzed by neutron activation analysis (INAA) and proton-induced X-ray emission analysis (PIXE) were subjected to factor analysis and chemical element balance to identify various emission sources and their contributions to the amibient aerosols. Hospital incinerators, contributing 22–36% to the ambient aerosols, were the major anthropogenic source at the receptor sites studied. Elevated concentrations of Ag, Cd, Cl, Cr, Sb and Zn were found in the hospital incinerator ash samples. Studies of the elemental concentrations of disposable hospital plastics and their fates during combustion indicate that these toxic elements found in the hospital waste and stack emissions are partly attributable to the extensive use of plastics in hospitals.

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Abstract  

In order to study the effects of air pollution, about 1,300 samples of airborne particulate matter (APM) were collected at suburban and industrial sites, in Daejeon, Korea from 1998 to 2006. The concentrations of carcinogenic (As and Cr) and non-carcinogenic metals (Al, Mn, and Zn) were determined by using instrumental neutron activation analysis (INAA). These long-term metal concentration data were applied to a risk assessment of inhalation exposure using Monte Carlo analysis (MCA).

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]. Biró , B , Köves-Péchy , K , Vörös , I , Kádár , M ( 1999 ): Intensification of nodulation and nitrogen-fixing activity preceding the “loss of function” by the long-term application of some toxic metal rates . In: Proc. 5th International

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49 231 246 Simon, L. and Koncz, J. (2011): Accumulation of toxic metals from sewage sludge compost in Salix viminalis and Arundo donax energy plants

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-reactivity, insolubility, chalking resistance, dispersibility, etc. [ 2 ]. However, most of conventional inorganic pigments contain the toxic metal such as Cd, Co, Cr, Hg, Pb and Sb that can adversely attack the environment and human health. Therefore, development

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