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Abstract  

Activated carbons (AC) have been long recognized as prominent absorbents in industries and feature numerous applications in preventing or absorbing the harmful gases and liquids and could be employed for filtration and remediation or even reutilization of chemicals. In order to investigate the capacity of AC in reducing the absorption of heavy metals (HM) including lead (Pb) and cadmium (Cd) and dual complex (Pb × Cd) by spinach, a factorial experiment in a completely randomized design with three replications on a pot trial was conducted. Three factors including five levels of AC 0, 5000, 10000, 15000, 20000 mg/kg soil, one concentration level of Pb 4,000 mg/kg soil and one concentration level of cadmium Cd 8 mg/kg soil were tested. The index of heavy metal concentration was calculated in leaf, stem and root and their corresponding dry weights. Results illustrated that in contaminated soils, plants with AC exhibited a superior reduction of absorption of HM vis-à-vis the plants without AC. The foremost result regarding the impact of AC on reducing the concentration of Pb and Cd was observed in 20,000 level of AC. This reveals that AC declined the soil contamination and lessened the accumulation of HM into the shoots and roots. Results suggest that the application of AC may be an eligible solution for decreasing the translocation of HM into the plants.

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.N. , Sinka , S. , Tripathi , R.D. and Chandra , P. 1995 . Wastewater treatability potential of some aquatic macrophytes: removal of heavy metals . Ecol. Eng. 5 : 5 – 12

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Abstract  

Pot experiments were carried out to assess the influence of two plantspecies on chemistry of polluted and unpolluted urban soils. Change in pHand acid neutralization capacity of the soils, as well as variations in elementalcomposition of soil leachates and in total concentrations of elements in thesoil were studied by INAA and ICP-AES. Concentrations of 28 elements in plantswere determined by INAA. Cultivation of plants led to significant change insoil parameters. In particular, acid neutralization capacity of polluted soilincreased, resulting in increase in element uptake.

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Abstract  

Eight soil profiles developed on crystalline basement complex rocks in the semi-arid region of Nigeria were analyzed for total contents of cesium (Cs), chromium (Cr), cobalt (Co), hafnium (Hf), iron (Fe), lanthanum (La), lutetium (Lu), scandium (Sc), thorium (Th), uranium (U) and ytterbium (Yb). The contents range from 50.3–95.4 Cs, 16.1–58.1 Cr, 0.6–9.0 Co, 9.0–34.8 g g–1 Hf, 0.31–3.69% Fe, 17.2–60.7 La, 60.4–90.6 Lu, 2.6–12.6 Sc, 8.3–21.5 Th, 4.7–9.2 U and 3.6–92 g g–1, Yb. Their corresponding means were 68.4, 35.1, 4.0, 19.9 g g–1, 1.70%, 37.1, 79.4, 6.5, 14.7, 6.7 and 5.0 g g–1. In general, total Cs, Co, Fe, La, U and Yb increased with further increase with depth. On the other hand, Lu, Sc and Th showed no distinct vertical distribution within the profiles. All eleven elements were correlated with the amounts of clay present in the soils, the correlation being stronger for Cs, Th, Yb, Cr and Lu.

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Abstract  

XRFS can be successfully used for routine on-line analysis of different agricultural products, for instance where food quality control is necessary. The optimization of the system for such purposes and the results obtained are shown on the example of the analysis of coffee.

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Abstract  

The aim of this work consisted on the implementation of sufficiently accurate and sensitive analytical procedure for the analysis of metal concentration in rainwater. Different sample preparation procedures were tested to achieve the required concentration prior to direct total reflection X-ray fluorescence (TXRF) analysis. TXRF and anodic stripping voltammetry (ASV) were compared in regard to achieved detection limits, precision and accuracy.

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Abstract  

The five step sequential extraction for speciation of copper and nickel originally designed for sediments has been applied to soil samples. The extractant solutions were: 1 mol/l ammonium acetate, 1 mol/l hydroxylammonium chloride in 25% acetic acid (1∶1), 0.1 mol/l hydrochlorid acid, 0.5 mol/l sodium hydroxide and 8 mol/l nitric acid. The residue was decomposed by HF and HNO3. Using this procedure the metal fraction bound to the organic matter can be distinguished. The concentrations of analytes were determined in the soil extracts by FAAS and ETAAS. Accuracy was assessed by comparing the sum of the contents of copper and nickel in soil extracts with the total certified values of CRMs of soils. The overall recovery values for nickel was 84–105% and for copper 105–114%.

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Abstract  

A method is described to determine traces of V, Fe, Ni, Zn, Nb and Mo in high purity matrices of niobium, tantalum and tungsten by non-destructive 14 MeV3He activation analysis. The influence of nuclear and γ-ray interferences in the determination of these elements is discussed.

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Abstract  

For systematic checking of the feasibility of determining elements by INAA in scalp hair, pubic hair and toenails, three different regimes were employed by varying the activation time and cooling time prior to -ray spectrometric measurements. The combination of these three regimes (activation time 1 min, cooling time 10 min; activation time 5 h, cooling time 5 d; activation time 5 h, cooling time 30 d) made it possible to determine the following 20 elements in most samples: Al, As, Br, Ca, Ce, Cl, Co, Cr, Cu, Fe, Hg, I, K, La, Mn, Na, S, Sb, Se, Zn. Further 10 elements (Ba, Cd, Mo, Ni, Rb, Sc, Sm, Th, V, W) were detectable only in some samples, however, with a fairly good precision, so that they could be detected in this way in the case of elevated concentrations exceeding physiological limits.

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Abstract  

Radionuclide X-ray fluorescence method with a Si/Li semiconductor detector and238Pu exciting source was used in the determination of Cr, Fe, Ni, Cu, and Zn content in industrial wastewaters. Simultaneously, the effects of the wastewaters on activated sludge biocenose were evaluated.

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