Skjelkvåle, B. L.; Stoddard, J. L.; Jeffries, D. S.; Tørseth, K.; Høgåsen, T.; Bowman, J.; Mannio, J.; Monteith, D.T.; Mosello, R.; Rogora, M.; Rzychon, D,; Vesely, J.; Wieting, J.; Wilander, A.; and Worsztynowicz, A., "Regional scale evidence for improvements in surface water chemistry 1990-2001" (2005 Data demonstrates a continued regional-scale chemical response of acid sensitive lakes and streams to emissions controls programs which is conducive to biological recovery. AbstractThe main aim of the international UNECE monitoring program ICP Waters under the Convention of Long-range Transboundary Air Pollution (CLRTAP) is to assess, on a regional basis, the degree and geographical extent of the impact of atmospheric pollution, in particular acidification, on surface waters. Regional trends are calculated for 12 geographical regions in Europe and North America, comprising 189 surface waters sites. From 1990e2001 sulphate concentrations decreased in all but one of the investigated regions. Nitrate increased in only one region, and decreased in three North American regions. Improvements in alkalinity and pH are widely observed. Results from the ICP Waters programme clearly show widespread improvement in surface water acid-base chemistry, in response to emissions controls programs and decreasing acidic deposition. Limited site-specific biological data suggest that continued improvement in the chemical status of acid-sensitive lakes and streams will lead to biological recovery in the future.

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The paper reports on the growth conditions of Li2B4O7 single crystals in both pure and Yb, Co, Mn doped systems. The crystals were grown by the Czochralski method using an intentional concentration of the above--mentioned ions at a level of 0.5 mol.%. The pure and Mn-doped crystals were found to be highly transparent and clear. The crystals doped with Yb 2 O 3 had a lot of precipitations making them opaque. The Co-doped crystals were purple-blue in colour and highly transparent. The growth of Yb and Co doped Li 2 B 4 O 7 crystals was reported for the first time in this paper. Absorption was measured in the range of 200 to 3200 nm, moreover analysis of changes in the absorption spectrum of γ-irradiated pure and doped Li 2 B 4 O 7 crystals was performed. Some thermoluminescence properties were measured, e.g. energies and lifetimes of the traps of different charge carriers occurring in the crystals at low temperatures.

Mercury contamination in the environment is problematic due to the unusual physical properties and well-recognized toxicity of this common metal. The bioavailability of mercury depends strongly on its chemical speciation. Anthropogenic mercury and its compounds appear in soil as "hot spots" located close to industrial facilities that used or produced mercury. The nature of the chemical production process, transportation and disposal practices often determined the chemical composition and distribution of mercury in the surrounding soils. Current ex situ soil remediation methods are expensive, produce undesirable side effects to the environment and usually involve transportation of contaminated soil. In this project, sponsored by the U.S. Department of Energy, a low-cost, simple approach to removing mercury from soil was evaluated. The process uses low-temperature thermal desorption of volatile metallic mercury and its compounds, and subsequent vapor capture. The project consisted of laboratory and plot-scale experiments. The laboratory efforts evaluated theoretical calculations of mercury removal as a function of time and temperature. The plot-scale experiment was a practical application of the laboratory results. For both experiments, mercury-polluted soil was obtained from a chemical production facility located in southern Poland. In laboratory experiments, at temperature 373 K total mercury concentration decreased in soil by nearly 32%. In plot-scale experiments, at temperature 440 K, about 60-70% of total mercury was removed from the soil. At the end of the experiment, a test of soil biological activity was performed to check if the high temperature applied to the soil did not impair the soil growth properties. There was no negative effect of temperature found.