Lichens as a useful mapping tool?—an approach to assess atmospheric N loads in Germany by total N content and stable isotope signature

To assess whether nitrogen (N) content and δ¹⁵N ratios in nitrophytic lichen species (Xanthoria parietina (L.) Th. Fr. (1860) and Physcia spp. (Schreb.) Michaux (1803)) reflect the quantity and quality of atmospheric N loads, 348 lichen samples from 174 sampling grid cells were investigated in the western part of Germany. The analysed lichen N content ranged between 0.98 and 4.28 % and δ¹⁵N ratios between ?15.2 and ?1.3?‰. Based on the N concentrations and the δ¹⁵N ratios of lichens, different landscape categories and coupled N deposition rates could be inferred for different regions of Germany. By analysing environmental variables like altitude, ammonia emission density, livestock unit and different defined deposition types, a direct relationship was found between lichen chemistry and N compounds produced from agricultural activity. The results support the development of a monitoring method which could be used nationally or even internationally to support current N deposition measurements, by providing reliable information on the quantity and quality of N deposition in high N environments.     

Safety Evaluation for a Biodiesel Process Using Prion-Contaminated Animal Fat as a Source (6 pp)

Background Due to the bovine spongiform encephalopathy (BSE), specified risk material (SRM) as well as animal meat and bone meal (MBM) are banned from the food and feed chain because of a possible infection with pathogenic prions (PrPSc). Nowadays, prions are widely accepted to be responsible for TSE(transmissible spongiform encephalopathies)-caused illnesses like BSE and scrapie, and especially for the occurrence of the new variant of CJD in humans. Presently, SRM and MBM are burnt under high temperatures to avoid any hazards for humans, animals or the environment. The aim of this study was to evaluate a method using animal fat separated from Category I material which includes SRM and the carcasses of TSE-infected animals, or animals suspected of being infected with TSE, as a source for producing biodiesel by transesterification, analogous to the biodiesel process using vegetable oil. Methods For this purpose, animal fat was spiked with scrapie-infected hamster brain equivalents – as representative for a TSE-infected animal – and the biodiesel manufacturing process was downscaled and performed under lab-scale conditions. Results and Discussion The results analysed by Western blotting showed clearly that almost each single step of the process leads to a significant reduction of the concentration of the pathogenic prion protein (PrPSc) in the main and side-products. Conclusion The data revealed that the biodiesel production, even from material with a high concentration of pathogenic prions, can be considered as safe. Recommendations and Outlook The obtained results indicated that biodiesel produced from prion-contaminated fat was safe under the tested process conditions. However, it has to be pointed out that the results cannot be generalized because a different process control using other conditions may lead to different results and then has to be analysed independently. It is clear that the production of biodiesel from high risk material represents a more economic usage than the combustion of such material.     

Conference report: 18th World Hydrogen Energy Conference 2010

Report is given on the 18th Word Hydrogen Energy Conference held on 16--20 May 2010 in Essen, Germany. Basic facts about conference organization, and its goal, scientific programme and conclusions are reviewed.     

Radiostrontium-90 (90Sr) Ultra-Traces Measurements by Coupling Ionic Chromatography (HPIC) and on Line Liquid Scintillation Counting (OLLSC)

The important role of the beta emitter Strontium-90 in our environmental has been studied since the nuclear age. This long half-life isotope (28.1 years) is produced in a relatively high yield (5.8 % from Uranium-235) during the fission of heavy elements. It has been reported to be the major artificial source of internal irradiation of the human body. Its valence shell electron configuration is the same as Calcium and so this isotope is easily fixed in the bones. The classical analysis of this particular isotope requires several weeks since it produces Yttrium-90 which is also a beta emitter. We developed a new trace analysis method by coupling High Performance Ionic Chromatography (HPIC), to separate Strontium-90 from natural or power plant reactor water, and on-line liquid scintillation counting detector, measuring the beta emission of low concentration Strontium-90 before Yttrium-90 is formed in a significant amount. We report here some analysis parameters : HPIC setup, scintillation cocktail, window, counting efficiency, linearity, pre-concentration and detection limits. We were able to determine very low concentrations of Strontium-90. The minimum concentration detected without a pre-concentration system was 0.5 ppt from a 200 µL sample (6.3×10-12 mole/L). The analysis only requires a few hours.     

An estimate on the rainout of atmospheric CO2

IntroductionCarboncirculatesbetweentheatmosphere ,biosphere ,oceansandthelithosphere(Warneck ,1988) .Thecarbonfluxesbetweenthesereservoirs,suchasburningoffuels ,photosynthesisandrespirationofecosystems,andtheuptakeoftheocean ,havebeenestimatedquantitative…