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Abstract  

An extensive investigation of elemental levels in cereals and their cultivation soils has been going on across the main production areas of mainland Portugal, with a view to an eventual biofortification of major cultivars through agronomic practices. Cereals are an obvious choice as primary vehicles for food-supplementation programs, especially in countries where they definitely weigh in the dietary intake (like Portugal), and regions whose geographical and/or pedological features may account for nutrient deficiencies in typical diets. Mature rye plants (Secale cereale L.; roots and grains) and local soils were collected in the summer of 2009 from two regions of northern Portugal, and put through k 0-standardized, instrumental neutron activation analysis (k 0-INAA). Overall, the results (elemental concentrations, enrichment factors, transfer coefficients) seem to confirm an efficient uptake of elements from soil and their translocation to the aerial parts of the plants, notably to the ones that really matter in human nutrition (grains).

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Abstract  

Airborne samples representing dustfall, street, and household dusts of Aswan were collected; and ten elements (Si, Ti, Fe, Mn, K, Al, Ca, Mg, Na, and P) were chemically analysed by means of instrumental activation analysis (INAA), inductively coupled plasma (ICP), and X-ray fluorescence (XRF). The puzziling differences in the values of the enrichment factors (EF) and obvious contradiction with the mineralogy of the dustfall samples both indicate that this method of calculation could help to establish models of dust matrices in different geological and industrial regions rather than considering it only as a tool for assessing the source rocks.

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Summary  

Trace element (TE) characterization and analysis in epiphytic lichens collected in different areas of the Himalayas (Nepal) and of the Alps (Italy) is presented. The results give information for the assessment of TE distribution present in the two different areas. The evaluation of the enrichment factors may provide information for many elements about their association to long-distance atmospheric transport phenomena. To this purpose, samples of superficial soils, collected in the same areas of those of the lichens, have also been analyzed. Most of the trace elements were determined by instrumental neutron activation analysis (INAA), while lead and cadmium measurements were carried out with electrothermal atomic absorption spectroscopy (ET-AAS).

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Journal of Radioanalytical and Nuclear Chemistry
Authors: S. Almeida, C. Ramos, A. Marques, A. Silva, M. Freitas, M. Farinha, M. Reis, and A. Marques

Abstract  

The objective of this paper was to assess the air pollution and the main sources of Air Particulate Matter in the Setúbal urban/industrial area, Portugal. PM2.5 and PM2.5–10 were sampled in Nuclepore filters and lichens transplants were exposed during 9 months. The levels of elements in these two matrixes were measured by INAA and PIXE. A large data base was created and source apportionment was performed by using Principal Component Analysis. The results showed that the main sources of fine particles were anthropogenic and were related with traffic and local industry. There was an important contribution of natural sources, mainly for the coarse fraction, associated with the sea and the soil. Lichens characterization and mapping showed that different site-specific characteristics controlled the spatial distribution of different elements. This study showed that biomonitoring is an effective complementary method to traditional sampling systems.

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enrichment factor simultaneously. LPME requires only a few microliters of organic solvents as the extraction solvent. Currently, LPME has many different operating methods, including gas phase and liquid phase methods, like single-drop microextraction (SDME

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separation and extraction technique that avoids the use of large quantities of organic solvents and provides high enrichment factors [ 19 – 21 ]. This technique is based on formation of a turbid solution by increasing the temperature or increasing additives

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TERCKEMAN , T. , V ILLANNEAU , E. , C IESIELSKI , H. , K ING , D. & B AIZE , D. , 2010 . Mapping of anthropogenic trace elements inputs in agricultural topsoils from Northern France using enrichment factors . Geoderma . 157 . 165 – 174

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equilibrium and extraction efficiency (enrichment factor, 273-fold). Thus, 60 min extraction time was selected. Although the extraction time was relatively long, many extractions can be simultaneously performed by using multi-stirrers. Salt is

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Abstract  

Chemical isotope effects of potassium and rubidium were studied bythe liquid-liquid extraction using a crown ether of dicyclohexano-18-crown-6.The isotope enrichment factors for unit mass difference were 0.0062+0.0013for potassium and 0.0018+0.0005 for rubidium. The correlation between theobtained isotope enrichment factors and the atomic weights was discussed withthe applicable values of literatures for the alkali metals.

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selected 90 °C as the optimal temperature. Effect of Sample Volume The volume of sample solutions can influence the equilibrium concentration of analytes in acceptor phase and the enrichment factor of analytes in

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