Remote sensing of substances in water

Remote sensing of water colour and its application to the mapping of pigments, suspended matter and other substances by means of airborne and spaceborne sensors is discussed. After an introduction to the physical process involved, the methods for a quantitative interpretation especially of CZCS data are indicated. Applications towards the monitoring of coastal pollution, of algae blooms and of dynamic processes are shown by means of selected examples. Multispectral scanner and imaging spectrometer technologies are discussed with special reference to NASA's Earth Observation System and ESA's Earth Observation Programme.     

MTBE in Drinking Water Production – Occurrence and Efficiency of Treatment Technologies

In Germany, the gasoline additive methyl tert‐butyl ether (MTBE) is almost constantly detected in measurable concentrations in surface waters and is not significantly removed during riverbank filtration. The removal of MTBE from water has been the focus of many studies that mostly were performed at high concentration levels and centred in understanding the mechanisms of elimination. In order to assess the performance of conventional and advanced water treatment technologies for MTBE removal in the low concentration range further studies were undertaken. Laboratory experiments included aeration, granulated activated carbon (GAC) adsorption, ozonation and advanced oxidation processes (AOP). The results show that the removal of MTBE by conventional technologies is not easily achieved. MTBE is only removed by aeration at high expense. Ozonation at neutral pH values did not prove to be effective in eliminating MTBE at all. The use of ozone/H₂O₂ (AOP) may lead to a partly elimination of MTBE. However, the ozone/H₂O₂ concentrations required for a complete removal of MTBE from natural waters is much higher than the ozone levels applied nowadays in waterworks. MTBE is only poorly adsorbed on activated carbon, thus GAC filtration is not efficient in eliminating MTBE. A comparison with real‐life data from German waterworks reveals that if MTBE is detected in the raw water it is most often found in the corresponding drinking water as well due to the poor removal efficiency of conventional treatment steps.     

Die faziesgebundene Tektonik vulkanischer Schwellen im ostrheinischen Schiefergebirge

Zusammenfassung Submarine Vulkane des Oberen Mitteldevons werden im Ostsauerland und Lahn-Dill-Gebiet von spilitischen Laven, Pillow-Breccien und glasreichen Tuffen aufgebaut. Ihre Mächtigkeiten schwanken zwischen 150 m und 600 m. Mit ihnen sind exhalativ-sedimentäre Hämatiterze genetisch verbunden. Auf den vulkanischen Schwellen bestehen während des Oberdevons Schichtlücken oder es werden geringmächtige Sedimente abgelagert. Sie sind Gebiete mit spezieller Bio- und Petrofazies. Die variskische Faltung hat die Vulkane zu Satteldomen, Schuppensätteln und Schuppen verformt. B-Achsen, Störungen und Klüftung sind in ihrer Anlage abhängig von der Petrofazies der Vulkanite und deren Festigkeitsanisotropien. Die Homogenität der Gefüge nimmt mit der Intensität der tektonischen Verformung zu.

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Submarine volcanoes of the Upper Middle Devonian in the Ostsauerland and Lahn-Dill-region, Western Germany, are built up by spilitic lavas, pillow-breccias and tuffs rich in glass. The thickness of the volcanic series ranges from 150 m to 600 m. Hematite ores of exhalative-sedimentary origin are genetically connected with them. In the upper Devonian there were stratigraphical breaks, or sediments of diminished thickness were deposited at the tops of the volcanic swells. They are characterised by the special development of the bio- and petrofacies. The variszic orogeny has deformed the volcanoes. Domes, sheared antiklines and disloged slices were formed by shearfolding. Fold-axes, faults and joints depend on the petrofacies and the variable rigidity of the volcanites. The homgeneity of the fabric increases with the intensity of tectonic deformation.

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Résumé En Sauerland oriental et en Lahn-Dill-région (Rheinisches Schiefergebirge) des pillow-laves et des pillow-brèches ainsi que des schalsteins tufogènes du volcanisme basaltique formaient des seuils volcaniques sous marins durant le Givétien supérieur. Les volcanites ont une épaisseurs de 160 m à 600 m. Des gisements d'hématite exhalatif-sédimentaires sont liés genétiquement à ces seuils. Durant le Dévonien supérieur ces régions sont caractérisées par des lacunes stratigraphiques, par des épaisseurs rèduites ainsi que par des évolutions particuliéres à l'égard du biofacies et du pétrofacies. Les mouvements orogénétiques déformaient ces volcans et formaient des dômes, des anticlinals d'une structure en écailles et des lames de charriage. Les axes des plis, les failles et les joints dépendent du pétrofacies et de la rigidité variante des volcanites. L'homogénité de leur structure tectonique augmente avec l'intensité de la déformation.

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Numerical simulation of lifetime and time-dependent damage for granite by continuous and discontinuous approaches

In this study, the time-dependent damage process of granite is investigated utilizing two numerical simulation schemes based on continuous method and discontinuous method. Numerical creep tests are carried out with both simulation schemes and mechanical responses and fracture patterns of rock specimens are analyzed. The calibrated numerical models can successfully reflect the typical creep stages observed in the laboratory. The predicted lifetime is in accordance with the laboratory test data. Comparisons are made between the two simulation schemes. It is found that both schemes have unique features that can promote a genuine reflection of the time-dependent damage process of the brittle rocks.     

Recommended Values of 239Pu, 240Pu and 239+240Pu Concentrations in Reference Material IAEA-315 (Marine Sediment) Estimated by Thermal Ionisation Mass Spectrometry, Inductively Coupled Plasma-Mass Spectrometry and Alpha Spectrometry

The recommended concentrations of ²³⁹Pu, ²⁴⁰Pu and ^239+240Pu in reference material IAEA‐315 (marine sediment) were estimated by three analytical methods: isotope dilution thermal ionisation mass spectrometry (TIMS), isotope dilution inductively coupled plasma‐mass spectrometry (ICP‐MS) and alpha spectrometry. The determination of ²³⁹Pu and ²⁴⁰Pu (^239+240Pu by alpha spectrometry) was carried out with samples from randomly selected bottles using each method. Plutonium‐238 was also measured by alpha spectrometry. A plutonium‐242 reference material was used as a spike for the quantitative analysis. The influence of ²⁴²Pu in the samples was therefore calculated; however, this contribution was less than the range of uncertainty and did not influence the final results. The obtained data were statistically analysed using variance component analysis and paired comparison. The combined standard uncertainties from “method/measurement”, “bottle” and “sub‐sample” were in the order of 3 to 6%. The main contributions to the uncertainty were from the material heterogeneity and from systematic differences between methods. Based on this study with twenty‐seven analyses using 10–14 g sample mass, concentrations of (38 ± 3) Bq kg^?1, (28 ± 3) Bq kg^?1 and (66 ± 4) Bq kg^?1 are proposed as recommended values for ²³⁹Pu, ²⁴⁰Pu and ^239+240Pu, respectively, and (9.5 ± 0.4) Bq kg^?1 for ²³⁸Pu as an information value in reference material IAEA‐315. In mass concentration units, these amount to (16.4 ± 1.2) ng kg^?1, (3.3 ± 0.4) ng kg^?1 and (0.015 ± 0.003) ng kg^?1 for ²³⁹Pu, ²⁴⁰Pu and ²³⁸Pu, respectively. The certified reference materials NIST 4350B and NIST 4354 were also analysed by TIMS for quality assurance of the method used in this study.