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Planar thin-layer chromatography of heavy metals has been performed on soil layers with aqueous solutions of amino acids as mobile phases. Several amino acids at different concentrations (0.5 to 5.0%) were tested to examine their effect on the mobility of the heavy metals. Increasing the concentration of the amino acids in the mobile phase resulted in increased mobility of most of the heavy metal ions studied. Neutral amino acids were capable of promoting differential migration among the heavy metals. Important separations of heavy metal ions from their mixtures were obtained with 2% aqueous solutions of neutral amino acids (alanine, serine, proline, valine, and methionine). When aqueous solutions of neutral amino acids were used as mobile phases, better separation of the heavy metals was achieved by use of a 2% solution of proline. Separations of heavy metals achieved experimentally on soil layers are listed.

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The natural radioactivity concentration and some heavy metals in various water and soil samples collected from seismically active area have been determined. Gross-alpha and beta concentrations of different 33 water samples and some heavy metal (Fe, Pb, Cu, K, Mn, Cr and Zn) concentration in 72 soil samples collected from two major fault systems (North and East Anatolian Active Fault Systems) in Turkey have been studied. This survey regarding gross-alpha and beta radioactivity and some heavy metals concentrations was carried out by means of Krieger method using a gross-alpha and beta-counting system and atomic absorption spectrometry (AAS), respectively. Also, gross annual effective dose from the average gross-alpha activity in waters were calculated.

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issue as sewage sludge is often highly contaminated with organic pollutants and heavy metals. Consequently, the amount of sewage sludge thermally treated (mono- or co-incineration and subsequent disposal of the ashes) significantly increased in the last

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An aqueous biphasic extraction system was designed using different molecular weights of polyethylene glycol and concentrated salt solutions of sodium sulphate to separate the heavy metals, Hg, Tl and Pb from Li irradiated Au matrix. All the four elements could be separated from one another by this extraction process by simply optimizing the salt rich phase, the pH of the salt rich phase and the molecular weight of the polymer rich phase.

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In various samples of marine organisms from the central Adriatic Sea 210Po was determined by alpha spectrometry and thirteen heavy metals (Mn, Fe, Co, Cr, V, Ni, Cu, Zn, Cd, As, Sn, Hg and Pb) by energy dispersive, polarised X ray fluorescence spectrometry (EDPXRF). 210Po activity concentration ranged between 0.3 and 44.6 Bq kg−1 fresh weight. The data obtained depend upon the type of the marine organism; among the pelagic species, anchovy displayed the highest polonium concentration. Typical concentration
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ranges were as follows: Mn: <1.32–1.73; Fe: 4.11–94.27; Co < 0.13–0.23; Ni: <0.13–0.52; Cu: 0.37–145.31; Zn: 0.46–16.46; Cd: <0.10–0.25; As: 0.36–60.52; Hg: <0.13–0.70; Pb: <0.13–0.35, Sn: <0.20–12.67; V and Cr were always <1.32. The data obtained are also compared with those obtained by other authors for the same organism coming from other Italian seas.
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Optimization of the separation and identification of heavy metals present in cotton material has been performed by TLC-densitometry after microwave digestion of cotton samples. The best separation was achieved on precoated microcrystalline cellulose layers with acetonitrile-conc. HCl-water as mobile phase. Optimization of the composition of the ternary mobile phase was achieved by use of experimental design software. Plates were visualized with quercetin-dimethylglyoxime-NH 3 reagent. A highly sensitive CCD color video camera was used to capture the chromatograms under white light.

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The street children phenomenon is an increasing problem in most cities of the world including Isfahan, which is a fast growing town. The number of street children with the growth of the town is increased. It is therefore important to have baseline data on their health problems. Hair element analysis remains an important tool in the nutritional and environmental assessment of them. A measurement of the elemental concentration in recently-grown hair provides an integrated view of the element status in the follicular cells and their blood supply, unaffected by short term fluctuations in the nutrient intake of the subject. This study aimed to assess heavy metals concentrations in the hair of street children in Isfahan using neutron activation analysis method. The concentration of heavy metals (Cu, Cr, Fe, Hg, Mn, and Zn) of 17 Iranian street children (Isfahan) was examined. Data analysis found that different profiles of the concentrations of Cr, Hg, Mn, and Zn were seen in each sample. These results were discussed with reference to show of environmental effects.

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Neutron activation analysis was used to investigate and quantify the level of heavy metal uptake in the marine environment of Lake Austin in Austin, TX. Specifically, the samples studied were largemouth bass, or micropterus salmoides. The presence of heavy metals in the food chain presents multiple hazards, mostly as a food hazard for those species that ingest the fish, namely humans. To measure the concentrations of heavy metals in various fish samples, the nuclear analytical technique of neutron activation analysis (NAA) was used. Both epithermal and thermal irradiations were conducted for the NAA to look for short and long-lived radioisotopes, respectively. The samples themselves consisted of liver and tissue samples for each of the fish caught. Each sample was freeze-dried and homogenized before irradiation and spectrum acquisition. The results showed that all levels of heavy metals were not sufficient enough to make the fish unsafe for eating, with the highest levels being found for iron and zinc. Gold was found to be at much higher concentrations in the younger fish and virtually non-existent in the larger of the samples.

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Results of determination of 137Cs, 90Sr, 40K, 239+240Pu, and heavy metals: Mn, Zn, Pb, Cd, Ni, Cr, Co, and Cu in skeletons of 15 species of birds of prey from Eastern Poland were presented. The greatest amounts of 137Cs and 90Sr (70 Bq/kg and 33 Bq/kg, respectively) were found in rough-legged buzzards (Buteo lagopus), winter visitors, coming from former soviet nuclear test places. Concentrations of 239+240Pu in raptors were negligible, only lesser-spotted eagles (Aquila pomarina) revealed slightly higher values. Median concentrations of 137Cs and 90Sr in raptors which feed predominantly on small mammals were higher in comparison to concentrations found in other ones preferring different trophy. The most noticeable was a very high lead concentration (reaching above 600 mg/kg) in birds which utilize un-retrieved hunting casualties as their prey.

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The sustainable development of agricultural waste is nowadays a main strategy in producing neutral CO2 energy and metal removal technologies. In Egypt, large amounts of rice straw are annually burnt in the open air causing severe air pollution that could be directed to co-firing and adsorption technologies. On bench scale, rice straw was positively contributed in a clean and smokeless co-firing process with methanol due to the oxidizing effect of the alcohol. The co-firing temperature control is vital to develop the adsorptive character of the residual ash and to avoid prolonged time needed to improve the physical properties of the rice straw if applied directly as a biosorbent. The consumed methanol in the process ranges from 0.15 to 0.3 liter per each kg of straw depending on its compaction. The grossed heat value from such process may drive steam generator for electricity. The residual ash was subsequently cross-linked in uranium and heavy metals adsorption tests from solutions. The porous texture of the residual ash and the amorphous nature of the silica along with potassium content provide a suitable condition for uranium immobilization especially if phosphorus or vanadium exist. The resulted chemical precipitate is analogues in composition to meta-ankoleite (KUO2PO4·3H2O) or hydrated carnotite (K2(UO2)2V2O8)·1-3H2O respectively. The XRD data of the latter form show an enhancement in crystallinity of the amorphous precipitate with the heated samples.

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