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| Registros recuperados: 32 | |
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| Dehairs, F.A.; Dedeurwaerder, H.; Dejonghe, M.; Decadt, G.; Gillain, G.; Baeyens, W.F.J.; Elskens, I.. |
| During 1980 and 1981 the aerosol burden as well as the wet and dry atmospheric fall-out of Cu, Cd, Pb, Zn, Fe and Mn to the sea have been studied in the Belgian coastal area. Atmospheric Cu, Zn and Cd are observed to be introduced into the sea mainly by wet fall-out, while Fe, Mn and also Pb have a dry and wet fall-out of similar magnitude. Of these elements, Cu, Zn and Cd have the highest washout factors. Furthermore, for all elements, excepted Mn, discrepancies exist between washout factors above land and sea, with values up to 5 times larger above the sea.On the scale of the North Sea, atmospheric fall-out of Cu, Zn, Pb and Cd exceeds by one order of magnitude the combined input of the rivers Scheldt, Rhine and Meuse, while fall-out of Fe and Mn is of... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1982 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=10065 |
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| Dedeurwaerder, H.L.; Dehairs, F.A.; Decadt, G.; Baeyens, W.F.J.. |
| In this study we have investigated air-sea exchanges in the Belgian coastal area located in the Southern Bight of the North Sea. Since 1980 the tropospheric aerosol contents for the trace elements Cd, Cu, Mn, Pb, Zn and for the reference elements Al , Fe, Na have been monitored on an intermittent basis from a maritime sampling platform (Light-Vessel West-Hinder; position: 51°23.5'N- 2°21.5'E, fig. 1). During 1981 sampling campaigns at sea were paralleled by sampling campaigns on land, in the coastal area (natural reserve De Blankaert, located at 20 Km inland), in order to allow for a better evaluation of the specific source or sink role of the sea. No major source of pollution exists between the maritime and the continental sampling sites. During these... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Aeolian deposits Resuspension Trace metals ANE; North Sea; Southern Bight. |
| Ano: 1984 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3323 |
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| Goeyens, L.G.; Stichelbaut, L.W.; Post, E.J.; Baeyens, W.F.J.. |
| A new procedure for the conversion of bound nitrogen into nitrogen gas, applicable to solid material, is described. It embodies two main stages: the catalytic ammonification of the sample and the consecutive transformation of ammonium to molecular nitrogen by the modified Dumas method. The first step of the preparation is carried out in a quartz reactor, filled with granular nickel, at a temperature of 700°C, the ammonia gas produced being trapped in sulphuric acid. In the second step, this solution is neutralised, dried and subjected to the Dumas combustion.The addition of reagents does not influence the results of the measurements. Spectrometric <sup>15</sup>N percentage abundances are converted into mass spectrometric "true"... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Emission spectroscopy. |
| Ano: 1985 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3279 |
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| Baeyens, W.F.J.; Gillain, G.; Ronday, F.; Dehairs, F.A.. |
| The residual flow lines of the Belgian coast are more or less parallel to the coast except in the area where the northeasterly flowing watermass coming from the Channel encounters the southwesterly-oriented Scheldt outflow. The result is a residual hydrodynamical front with, at the northern side, a less saline estuarine watermass, and at the southern side a more saline marine watermass. From the steady-state salinity pattern, diffusion coefficients perpendicular to the residual flow were deduced; they ranged from 21 to 108 m².s<sup>-1</sup>.The steady-state profiles of dissolved metals versus salinity indicate a dilution effect in the coastal-estuarine watermass and almost constant concentration in the marine watermass. Offshore fluxes of Cd,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Coastal zone Trace metals ANE; North Sea. |
| Ano: 1987 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3156 |
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| Lansens, P.; Baeyens, W.F.J.. |
| An improvement in the extraction step in the method of Decadt et al. for determining methylmercury in biological tissues is described. The methylmercury is released from the tissue by use of sulphuric acid as the cleaving agent and immediately converted to the iodide form by iodoacetic acid. These reaction steps take place in a closed headspace vial. The methylmercury iodide is then headspace-injected into a gas-chromatograph and detected with a microwave-induced plasma detector. Quantitation is accomplished by standard addition. Analysis of one sample takes less than 15 min. The detection limit of the method is 20 ng methylmercury per gram biological tissue when 50 mg of tissue are taken. |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1990 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3091 |
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| Panutrakul, S.; Baeyens, W.F.J.. |
| The Ballasplaat intertidal mud flat in the Scheldt estuary has been polluted by Cd and Pb and also high amounts of organic matter as a result of suspended matter deposition. The degree of pollution is, however, not uniform over the mud flat due to varying physico-chemical conditions (essentially variable redox profiles). Measurements of the redox profile, and the metal concentrations in the pore water, the total sediment and the fraction <63 µm combined with sequential extraction results and enrichment factors can explain the behaviour of Cd, Pb, Fe and Mn in the sediments. In a strong anoxic sediment, where sulphate reducing bacteria are active, the heavy metals are trapped as poorly soluble metal complexes while in an oxic or suboxic sediment metals... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cadmium Chemical reactions Estuaries Iron Lead Manganese Marine pollution Mud flats Physicochemical properties Sediment chemistry Sediment pollution Sediments ANE; Netherlands; Westerschelde; Ballastplaat. |
| Ano: 1991 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3112 |
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| Baeyens, W.F.J.; Dedeurwaerder, H.. |
| Heavy metal concentrations in total particulate suspended matter and size fractionated particulate suspended matter above the Southern Bight of the North Sea have been assessed. Most of the samples were collected from a light vessel; the total sampling period covered about 70 days at sea. Stringent precautions were taken during sampling, storage, handling and analysis of the samples. As a conclusion, we found that on a long-term basis the aerosol concentrations above the North Sea have a fairly homogeneous composition, but short-term variations probably resulting from point emissions were observed. The cascade impactor results indicated that Pb, Cu, Cd and Zu were carried by submicrometer aerosols, Na, Fe, Mn and Al by supermicrometer aerosols. Most of the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Aerosols Air pollution Atmospheric particulates Meteorology Seasonal variations Statistical analysis Trace metals Troposphere Winds ANE; North Sea; Southern Bight. |
| Ano: 1991 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3106 |
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| Registros recuperados: 32 | |
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