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Pierwszy komunikat o odkryciu polonu zredagowany i własnoręcznie napisany przez Marię Skłodowską-Curie

100%

Mierzecki R.

Analecta. Studia i Materiały z Dziejów Nauki

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2011

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tom 20

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nr 1

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The contribution of the fine sediment fraction to the Fluffy Layer Suspended Matter (FLSM)

84%

Pempkowiak J., Beldowski J., Pazdro K., Staniszewski A., Leipe T., Emeis K. C.

Oceanologia

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2002

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tom 44

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nr 4

Fluffy Layer Suspended Matter (FLSM) is a layer of fairly concentrated suspended matter resting on the sea floor. Its passage to the depositional basins in the Pomeranian Bay – Arkona Deep System of the Baltic Sea is estimated to take around six months. In the course of this migration, the properties of FLSM change as a result of ageing and the influx of fresh particles from the water column, and possibly also because of mass exchange with the uppermost sediment layers. Measurements of radioisotopes (210Po, 210Pb, 137Cs) have demonstrated that in shallow water this topmost layer of sediments, from 8 cm to 3 cm in thickness, is subject to mixing. This creates redox profiles favourable to biota and bioturbation. Basing on 210Pb/210Po disequilibria and the 210Po excess, it was estimated that under steady state conditions from 1.5 to 2.2% of fine fraction (FSF) in the mixed layer of sediments is freshly imported from FLSM. This implies replacement of FSF from the sediments and its incorporation into FLSM. On the assumption that the surface density of FLSM is 10 mg cm−2, FSF freshly exported from sediments actually comprises up to 15% of FLSM. Therefore, the properties of FLSM are strongly influenced by the processes taking place in the sediments, although FLSM by definition is independent of sediments.

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Accumulation of polonium by Mytilus trossulus under experimental conditions

84%

Stepnowski P., Kozuch J.

Oceanological Studies

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1999

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tom 28

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nr 1-2

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Polonium, uranium and plutonium radionuclides in aquatic environment of Poland and Southern Baltic

67%

Skwarzec B.

Baltic Coastal Zone. Journal of Ecology and Protection of the Coastline

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2009

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tom 13 part II

In the paper were presented the results of study for determination of natural (polonium 210Po, uranium 234U and 238U) and artificial (plutonium 238Pu, 239+240Pu and 241Pu) alpha radionuclides in aquatic environment of Poland and southern Baltic Sea as well as the recognition of their accumulation in marine trophic chain. The obtained results indicated that Vistula and Odra as well as Rega, Parsęta and Słupia are important sources of analyzed radionuclides in southern Baltic Sea. Total annual runoff of polonium, uranium and plutonium from Vistula, Odra and Pomeranian rivers to the Baltic Sea was calculated as about 95 GBq of 210Po, 750 GBq of 234+238U and 160 MBq of 238+239+240Pu. Investigation on the polonium 210Po, uranium 234U and 238U, as well as and plutonium 238Pu, 239+240Pu and 241Pu. concentration in Baltic biota revealed that these radionuclides, especially polonium and plutonium, are strongly accumulated by some species. The results indicate that the Baltic organisms accumulate polonium and plutonium from environment and the bioconcentration factors (BCF) range from 25 to 27 000. The Baltic Sea algae, benthic animals and fish concentrate uranium only to a small degree. In Baltic sediments, the concentration of uranium increases with core depth and it is connected with the diffusion of 234U, 235U and 238U from sediments via intersticial water to bottom water. The values of 234U/238U activity ratio in the sediments indicated that the possible reduction process of U(VI) to U(IV) and the removing of autogenic uranium from seawater to sediments in the Gdańsk Deep and Bornholm Deep constitutes a small part only.

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Polonium, uranium and plutonium in the Southern Baltic Sea

67%

Skwarzec B.

Oceanological Studies

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1997

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tom 26

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nr 1

Ograniczanie wyników

2 Oceanological Studies

1 Analecta. Studia i Materiały z Dziejów Nauki

1 Baltic Coastal Zone. Journal of Ecology and Protection of the Coastline

1 Oceanologia

2 Skwarzec B.

1 Beldowski J.

1 Emeis K. C.

1 Kozuch J.

1 Leipe T.

1 Mierzecki R.

1 Pazdro K.

1 Pempkowiak J.

1 Staniszewski A.

1 Stepnowski P.

1 2011

1 2009

1 2002

1 1999

1 1997

Pierwszy komunikat o odkryciu polonu zredagowany i własnoręcznie napisany przez Marię Skłodowską-Curie

The contribution of the fine sediment fraction to the Fluffy Layer Suspended Matter (FLSM)

Accumulation of polonium by Mytilus trossulus under experimental conditions

Polonium, uranium and plutonium radionuclides in aquatic environment of Poland and Southern Baltic

Polonium, uranium and plutonium in the Southern Baltic Sea