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Abstract  

Seventeen trace elements (As, Ce, Co, Cr, Cs, Eu, Fe, Hg, Hf, La Lu, Rb, Sb, Sc, Sm, Yb and Zn) have been determined by Instrumental Neutron Activation Analysis in sediments from the upper Saronikos Gulf, Greece. It was found that the discharge of industrial and domestic wastes in the Keratsini and Elefsis bays of the upper Saronikos Gulf had led to elevated concentrations of all toxic and other trace elements determined over at least 100 km2 of seafloor. Increases above natural level range from 2 fold for rare earths to 200 fold for arsenic.

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Abstract  

Aerosol samples from urban, industrial and traffic areas were collected and analyzed for various elements. The correlation between the multielement content of the samples and their sources was studied. It was found necessary to anlayze samples before and after ashing because, while ashing improves the peak-to-background ratio, volatile elements may be lost. Samples collected at heights of 1.5 and 15 m were found to have the same elemental composition. Samples collected on consecutive filters showed sharp elemental fractionation An example of source identification is given for a high traffic area as compared with an area in which a large bromine plant is located. In both cases different Pb∶Br ratios were observed, with high bromine concentration in the latter. The analytical method used was based on the detection of characteristic K and L X-rays induced by a241Am-I source-target assembly.

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Abstract  

Most elemental concentrations in crops should be related to those in soil and other circumferential environments. In the present study, more than thirty minor and trace elements in soils and crops were determined by the use of ICP, XRF and NAA. Soil and crop samples were collected at eleven abandoned mine regions in Chungnam province located in the middle part of Korea. The elemental concentrations in soils were compared to the crustal mean concentrations in both Chungnam area and worldwide. The concentration ratios of the elements in soils and crop compartments were calculated and the distribution characteristics of each element were investigated between soil and crop compartments.

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Abstract  

Instrumental Neutron Activation Analysis (NAA) has been applied for the determination of Ag and Sb in water column, sediment cores, and two marine organisms from Saronikos Gulf, Greece. Higher levels of Ag and Sb were found in the water column and cores from polluted areas of the Gulf as compared to those from unpolluted areas. No significant differences of Ag and Sb were found in the two marine organisms from all areas of Saronikos Gulf.

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Abstract  

Long-lived fission radionuclides spread out after the Chernobyl accident have been measured in samples collected from the Black Sea and at the Aegean coasts of Turkey between June 15 and September 15, 1987. Nondestructive analysis was performed using high resolution -spectroscopy. The activity remaining 16 months after the event was found to be enhanced in coniferous needles as well as in lichens, while foodstuff did not show any appreciable contamination. The relatively high106Ru/134Cs and144Ce/134Cs ratios compared to those found in analogous samples from Southern Europe, might result from a fractionation between refractory and volatile elements.

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Abstract  

During the course of field work in the Chamonix-Argentière area of the Western Alps of France, low pH's (by field testing) were measured in soils of later Pleistocene and Holocene age. Subsequently, data derived from laboratory investigations showed high electrical conductivities (mainly from high SO 4 2– ) and pH values as low as 3.9 in epipedons of Inceptisols and Spodosols. Proximity to coal-fired electrical generating stations and industrial activity in le Fayet and Sallanches (20 km to Northwest) may generate considerable output of SO 4 2– ions which, along with arsenic, antimony and bromine, survive transport up valley by anabatic wind systems. Because the country rock in the Chamonix area is largely an acidic crystalline complex of granite and gneiss, the tendency for lower pH's in the surface soils may have a disastrous effect on the coniferous forests in the area.

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Abstract  

Radium isotopes were measured in groundwater near a radioactive storage facility with contained pasty residues from monazite and industrial processing sealed in concerete reserouirs. The concentration of radium isotopes in the water was slightly higher than found in the normal drinking water. The measured228Ra to225Ra ratio in the groundwater is not compatible with calculations of radium isotopes ingrow and docay in cake II for different elapsed times, leaving mesothorium cake as the most likely source of contamination.

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Abstract  

Analysis of lichens and mosses were routinely performed by 17 laboratories from 15 countries around the world, participating in a project coordinated by the International Atomic Energy Agency (IAEA). To improve and control the quality of such determinations, the IAEA organized a two-round interlaboratory exercise, which allowed the detection and removal of most of the pitfalls observed in the determination of 27 elements. The application of instrumental neutron activation analysis helped reveal poor recoveries in some laboratories due to incomplete digestion for a number of elements. The exercise emphasized the importance of achieving comparability of chemical measurements to a recognized reference.

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Abstract  

Trace element concentrations in weathering crusts are determined by neutron activation analysis. A high temperature volatilization technique was applied to determine mercury. Comparing the concentrations in samples of different ages, the variations of the air pollutants are shown.

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Abstract  

The lanthanide elements, Th and U were measured in soils and agricultural crops collected in an area polluted by emissions from a phosphate fertilizer plant. Concentrations of the above elements in the soil and crop samples were determined by instrumental neutron activation analysis (INAA). Selected crop samples were also analyzed using radiochemical neutron activation analysis (RNAA) based on alkaline-oxidative fusion of the irradiated samples followed by precipitation of REE oxalates. Elevated levels of lanthanides, Th and U were found in some samples, especially in wheat chaff and parsley.

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