| 1. |
- Edner, H, et al.
(författare)
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Differential Absorption Lidar Mapping of Atmospheric Atomic Mercury In Italian Geothermal Fields
- 1992
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Ingår i: Journal of Geophysical Research. - 2156-2202. ; 97:D4, s. 3779-3786
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Tidskriftsartikel (refereegranskat)abstract
- Results from extensive lidar measurements on atmospheric atomic mercury in Italian geothermal fields are reported. A mobile differential absorption lidar system operating on the 254-nm mercury resonance line with a measuring range of about 1 km was used in mineralized as well as nonmineralized areas. Measurements were performed at geothermal power stations and in an unexploited field with natural surface geothermic manifestations. Atomic mercury concentrations ranging from 2 to 1000 ng/m3 were mapped. The high Italian geothermal mercury concentrations are in strong contrast to the recent lidar finding of the absence of atomic mercury in Icelandic geothermal fields.
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| 2. |
- Ferrara, R, et al.
(författare)
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Atmospheric Mercury Emission At Solfatara Volcano (Pozzuoli, Phlegraean Fields, Italy)
- 1994
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Ingår i: Chemosphere. - : Elsevier BV. - 1879-1298 .- 0045-6535. ; 29:7, s. 1421-1428
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Tidskriftsartikel (refereegranskat)abstract
- Mercury concentrations in air and in condensed steam coming from fumarolic activity at the Solfatara crater (Phlegraean Fields - Italy) were determined. In the condensed steam, mercury was found mainly associated as Hg-S complexes and showed a flux in the range from 0.9 to 4.5 g day(-1). Using the point monitor technique, high values (up to 690 ng m(-3)) of atmospheric mercury levels were observed only close to the main exhaling areas, while background levels (2 ng m(-3)) were measured over the crater area using the lidar technique. An upper limit (<2.4 g day(-1)) for the flux of elemental mercury in air was estimated with the lidar. This remote sensing technique also allowed to assess an upper limit for the SO2 flux (<24 kg day (-1)).
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| 3. |
- Ferrara, R, et al.
(författare)
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Vertical Profiles of Atmospheric Mercury Concentration
- 1992
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Ingår i: Environmental Technology. - : Informa UK Limited. - 1479-487X .- 0959-3330. ; 13:11, s. 1061-1068
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Tidskriftsartikel (refereegranskat)abstract
- Vertical profiles of atmospheric mercury concentration determined with a lidar and point monitor systems in the mineralized region of Mt. Amiata (Italy) are reported. Measurements were performed over a large flat area, without arboreal and herbaceous vegetation, constituting a roasted cinnabar deposit which still contains about two parts per thousand of mercury. The determinations carried out with the two techniques yielded comparable results for the working conditions used. Data demonstrate the presence of a vertical gradient of atmospheric mercury concentration, which is particularly large in the layers of air nearest the soil. The highest values (45-1000 ng m-3) were measured a few centimeters from the soil, while background values (2-3 ng m-3) were reached at heights of 10-20 m. The vertical gradient proved to be strongly dependent on ambient temperature.
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