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Concentrations of (210)Pb and (7)Be in air were continuously monitored, using a high-volume air sampler and a high-resolution gamma-ray spectrometer, during the period of July 2002 to June 2003 at the University of Edinburgh 55.9 degrees N, 03.2 degrees W. The time series of both radio-isotopes show seasonality, dependence on air-mass origin, residence time and precipitation. Surface air concentrations of (210)Pb and (7)Be ranged from 0.01 to 0.74 mBq m(-3) and 0.63-6.54 mBq m(-3), respectively. The measurements indicate that the average concentrations of both (210)Pb and (7)Be in surface air were 0.21+/-0.01 and 2.50+/-0.04 mBq m(-3), respectively; which agrees closely with the corresponding values reported for coastal air measurements in Europe.  相似文献   

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Due to the importance of bottled mineral water in human diet with special regard to children in lactation period, a monitoring of natural radioactivity in some bottled mineral waters produced in Italy was performed. Gross alpha and beta activities and (226)Ra, (238)U, (234)U, and (210)Po concentrations were measured. Gross alpha and beta activities were determined by standards ISO 9696 and ISO 9697; for (226)Ra determination liquid scintillation was used. The (238)U and (234)U concentrations were determined by alpha spectrometry after their separation from matrix by extraction chromatography and electroplating. (210)Po was measured by alpha spectrometry. The results revealed that the concentrations (mBqL(-1)) of (226)Ra, (238)U, (234)U, and (210)Po ranged from <10.00 to 52.50, from <0.17 to 89.00, from <0.17 to 79.00, and from <0.04 to 21.01, respectively. Uranium and radium concentrations do not reach the relevant recommended derived activity concentration (DWC). For polonium concentration, none of the samples reaches the relevant DWC in the case of adults and children, but one sample exceeds this value for infants. The dose contribution for different classes of age was calculated using the dose coefficient factors reported by EC Directive 96/29 EURATOM and certain annual intake. For children and adult age class, the calculated doses are quite similar and lower than 0.1mSvy(-1); for infants (<1y) in three cases the calculated dose ranges from 0.11 to 0.17mSvy(-1).  相似文献   

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