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- ItemShallow shear-wave reflection seismics in the tsunami struck Krueng Aceh River Basin, Sumatra(Katlenburg-Lindau : European Geosciences Union, 2008) Polom, U.; Arsyad, I.; Kümpel, H.-J.As part of the project "Management of Georisk" (MANGEONAD) of the Federal Institute for Geosciences and Natural Resources (BGR), Hanover, high resolution shallow shear-wave reflection seismics was applied in the Indonesian province Nanggroe Aceh Darussalam, North Sumatra in cooperation with the Government of Indonesia, local counterparts, and the Leibniz Institute for Applied Geosciences, Hanover. The investigations were expected to support classification of earthquake site effects for the reconstruction of buildings and infrastructure as well as for groundwater exploration. The study focus sed on the city of Banda Aceh and the surroundings of Aceh Besar. The shear-wave seismic surveys were done parallel to standard geoengineering investigations like cone penetrometer tests to support subsequent site specific statistical calibration. They were also partly supplemented by shallow p-wave seismics for the identification of (a) elastic subsurface parameters and (b) zones with abundance of groundwater. Evaluation of seismic site effects based on shallow reflection seismics has in fact been found to be a highly useful method in Aceh province. In particular, use of a vibratory seismic source was essential for successful application of shear-wave seismics in the city of Banda Aceh and in areas with compacted ground like on farm tracks in the surroundings, presenting mostly agricultural land use areas. We thus were able to explore the mechanical stiffness of the subsurface down to 100 m depth, occasionally even deeper, with remarkably high resolution. The results were transferred into geotechnical site classification in terms of the International Building Code (IBC, 2003). The seismic images give also insights into the history of the basin sedimentation processes of the Krueng Aceh River delta, which is relevant for the exploration of new areas for construction of safe foundations of buildings and for identification of fresh water aquifers in the tsunami flooded region.
- ItemCorrelation of carbon nanotube dispersability in aqueous surfactant solutions and polymers(New York, NY [u.a.] : Pergamon Press, 2009) Krause, Beate; Petzold, Gudrun; Pegel, Sven; Pötschke, PetraIn order to assess the dispersability of carbon nanotube materials, tubes produced under different synthesis conditions were dispersed in aqueous surfactant solutions and the sedimentation behaviour under centrifugation forces was investigated using a LUMiFuge stability analyzer. The electrical percolation threshold of the nanotubes after melt mixing in polyamide 6.6 was determined and the state of dispersion was studied. As a general tendency, the nanotubes having better aqueous dispersion stability showed lower electrical percolation threshold and better nanotube dispersion in the composites. This indicates that the investigation of the stability of aqueous dispersions is also able to give information about the nanotubes inherent dispersability in polymer melts, both strongly influenced by the entanglement and agglomerate structure of the tubes within the as-produced nanotube materials. The shape of the nanotubes in the aqueous dispersions was assessed using a SYSMEX flow particle image analyzer and found to correspond to the shape observed from cryofractured surfaces of the polymer composites. © 2008 Elsevier Ltd. All rights reserved.
- ItemMapping High-Temperature Superconductors—A Scientometric Approach(New York, NY : Springer, 2008) Barth, Andreas; Marx, WernerThis study has been carried out to analyze the research field of high-temperature superconductivity and to demonstrate the potential of modern databases and search systems for generating meta-information. The alkaline earth (A2) rare earth (RE) cuprate high-temperature superconductors as a typical inorganic compound family and the corresponding literature were analyzed by scientometric methods. The time dependent overall number of articles and patents and of the publications related to specific compound subsets and subject categories are given. The data reveal a significant decrease of basic research activity in this research field. The A2 RE cuprate species covered by the CAS compound file were analyzed with respect to the occurrence of specific elements in order to visualize known and unknown substances and to identify characteristic patterns. The quaternary and quinternary cuprates were selected and the number of compound species as a function of specific combinations of A2 and RE elements is given. The Cu/O and RE/A2 ratios of the quaternary cuprate species as a function of A2 and RE atoms are shown. In addition, the research landscape of the MgB2 related publications was established using STN AnaVist, an analysis tool recently developed by STN International.
- ItemCombined rock slope stability and shallow landslide susceptibility assessment of the Jasmund cliff area (Rügen Island, Germany)(Katlenburg-Lindau : European Geophysical Society, 2009-5-8) Günther, A.; Thiel, C.In this contribution we evaluated both the structurally-controlled failure susceptibility of the fractured Cretaceous chalk rocks and the topographically-controlled shallow landslide susceptibility of the overlying glacial sediments for the Jasmund cliff area on Rügen Island, Germany. We employed a combined methodology involving spatially distributed kinematical rock slope failure testing with tectonic fabric data, and both physically- and inventory-based shallow landslide susceptibility analysis. The rock slope failure susceptibility model identifies areas of recent cliff collapses, confirming its value in predicting the locations of future failures. The model reveals that toppling is the most important failure type in the Cretaceous chalk rocks of the area. The shallow landslide susceptibility analysis involves a physically-based slope stability evaluation which utilizes material strength and hydraulic conductivity data, and a bivariate landslide susceptibility analysis exploiting landslide inventory data and thematic information on ground conditioning factors. Both models show reasonable success rates when evaluated with the available inventory data, and an attempt was made to combine the individual models to prepare a map displaying both terrain instability and landslide susceptibility. This combination highlights unstable cliff portions lacking discrete landslide areas as well as cliff sections highly affected by past landslide events. Through a spatial integration of the rock slope failure susceptibility model with the combined shallow landslide assessment we produced a comprehensive landslide susceptibility map for the Jasmund cliff area.
- ItemGoportis – hoch integrierte Kooperation der Zentralen Fachbibliotheken(Bingley : Emerald, 2008) Burblies, Christine; Pianos, TamaraUnter dem Namen „Goportis“ haben die drei Deutschen Zentralen Fachbibliotheken (ZFB) im Herbst 2006 begonnen, eine hoch integrierte Kooperation auf der Ebene gemeinsamer Produkte und Dienstleistungen und interner Geschäftsgänge aufzubauen. Die Zentralen Fachbibliotheken sind die Technische Informationsbibliothek in Hannover, die Deutsche Zentralbibliothek für Medizin in Köln/Bonn und die Deutsche Zentralbibliothek für Wirtschaftswissenschaften in Kiel/Hamburg.
- ItemInfluence of small scale melt mixing conditions on electrical resistivity of carbon nanotube-polyamide composites(Barking : Elsevier, 2009) Krause, Beate; Pötschke, Petra; Häußler, LianePolyamide 6 (PA6) and polyamide 6.6 (PA66) were filled with multiwalled carbon nanotubes (MWNT) using small scale melt mixing under variation of processing conditions, including temperature, rotation speed, and mixing time. In PA66 an electrical percolation threshold of 1 wt% MWNT was found which is lower than that of PA6 at 2.5-4 wt%. In both cases mixing conditions influenced strongly the dispersion and distribution of CNT and the electrical volume resistivity, whereas crystallisation behaviour was only slightly changed. With increasing mixing energy input remaining agglomerates were less in number and smaller, leading to better dispersion. On the other hand, in samples containing 5 wt% MWNT in PA6 electrical volume resistivity showed a minimum at a quite low energy input and then increased considerably with further input of mixing energy. This increase may be related to MWNT breaking during mixing and encapsulation of MWNT by the polyamide chains. © 2008 Elsevier Ltd. All rights reserved.
- ItemAnalysis of Boundary Element Methods(Zürich : EMS Publ. House, 2008) Stephan, Ernst P.[no abstract available]
- ItemAlgebraic K-Theory and Motivic Cohomology(Zürich : EMS Publ. House, 2009) Huber-Klawitter, Annette; Jannsen, Uwe; Levine, MarcAlgebraic K-theory and the related motivic cohomology are a systematic way of producing invariants for algebraic or geometric structures. Its definition and methods are taken from algebraic topology, but it has also proved particularly fruitful for problems of algebraic geometry, number theory or quadratic forms. 19 one-hour talks presented a wide range of results on K-theory itself and applications. We had a lively evening session trading questions and discussing open problems.
- ItemMini-Workshop: The Pisot Conjecture - From Substitution Dynamical Systems to Rauzy Fractals and Meyer Sets(Zürich : EMS Publ. House, 2009) Damanik, David; Lenz, DanielThis mini-workshop brought together researchers with diverse backgrounds and a common interest in facets of the Pisot conjecture, which relates certain properties of a substitution to dynamical properties of the associated subshift.
- ItemMini-Workshop: The Mathematics of Electro-Active Smart Materials(Zürich : EMS Publ. House, 2008) Ogden, Ray; Saccomandi, Guiseppe[no abstract available]