Integrierter Ansatz zur Beurteilung eines Aufsuchungsantrages auf Schiefergas in Hessen

In the context of an application for a shale gas exploration license including hydraulic fracturing, the Geological Survey of Hessen (HLNUG) has grouped and ranked structural geological regions in terms of their shale gas potential and the function of overlying rocks as barriers. Tectonic and structural features as well as the type of reservoir have been examined. Rock units overlying the shale gas layers have been classified as hydrogeological units and divided into aquifers and hydraulic barriers. Possible effects on drinking water abstraction facilities, mineral springs and water for industrial use have also been estimated, followed by an analysis of competing requirements for land use. A potential for shale gas can only be identified in a region north of Kassel, covering about 16?% of the claim area. Approximately 65?% of this region is overlapped by protection areas for drinking water and mineral springs, nature reserves and many other areas of public interest.     

Time-hierarchical scheduling

In this paper, the general time hierarchical planning and scheduling approach is introduced, which integrates both detailed scheduling and due date assignment for an online problem. In this approach, time is divided into intervals of increasing size, and the different sizes form a hierarchy. We show that for a simplified model, a multiple level bin packing approach is an approximation algorithm, and we further prove that under weak assumptions, the approximation quality is bounded independently of the depth of the hierarchy.     

T?ne sehen? Zur Visualisierung Akustischer Ph?nomene in der Herzdiagnostik

During the nineteenth century physiologists and clinicians developed several graphical recording systems for the mechanical registration of heart sounds. However, none of these replaced traditional methods of auscultation. The paper describes criticism of the aural sense as one of the driving forces behind the development of phonocardiography and analyses its variants from a technological and clinical perspective. Against the background of the physiological “method of curves,” the parameters that prevented the implementation of phonocardiography against overwhelming odds are highlighted. Contemporaries denied specific evidence beyond auscultation. Many clinicians also feared that the art of auscultation was being undermined by the new, reproducible mechanical methods. The paper argues that phonocardiography was on the one hand regarded as impractical in clinical settings; on the other hand—and even more important—implicit practices, tacit knowledge and cultural models fostered skepticism against the new method. The argument of “self-evidence”—often connected to medical images, curves, graphs or tables—was not valid for the visualization of cardiac sounds in the opinion of the promoters of acoustic heart sound registration and its individual interpretation. Rather, the acts of subjective hearing and objectively reporting what was heard seemed “self-evident” for pathophysiological characteristics and the development of a diagnosis. Therefore, auscultation and phonocardiography coexisted with different emphases. While auscultation remained the method of choice for a bedside diagnosis, phonocardiography played its role in differential diagnostics or research settings.     

On deactivation of CrOx/La2O3/ZrO2 catalyst during n‐octane dehydrocyclisation. I. Investigation of dehydrogenation capability by the homomolecular H–D exchange of molecular hydrogen

Based on the time on stream dependence of product distribution during deactivation and on additional investigations of fresh and deactivated samples by the homomolecular H–D exchange of molecular hydrogen, it is concluded, that the deactivation during n‐octane dehydrocyclisation on CrO_x/La₂O₃/ZrO₂ catalysts is caused by a decreasing dehydrogenation capability of the active surface and not by increasing mass transport resistance. This revised version was published online in July 2006 with corrections to the Cover Date.     

Using Polymer Electrolyte Gates to Set‐and‐Freeze Threshold Voltage and Local Potential in Nanowire‐based Devices and Thermoelectrics

The strongly temperature‐dependent ionic mobility in polymer electrolytes is used to “freeze in” specific ionic charge environments around a nanowire using a local wrap‐gate geometry. This makes it possible to set both the threshold voltage for a conventional doped substrate gate and the local disorder potential at temperatures below 220 K. These are characterized in detail by combining conductance and thermovoltage measurements with modeling. The results demonstrate that local polymer electrolyte gates are compatible with nanowire thermoelectrics, where they offer the advantage of a very low thermal conductivity, and hold great potential towards setting the optimal operating point for solid‐state cooling applications.     

Writing Silica Structures in Liquid with Scanning Transmission Electron Microscopy

Silica nanoparticles are imaged in solution with scanning transmission electron microscopy (STEM) using a liquid cell with silicon nitride (SiN) membrane windows. The STEM images reveal that silica structures are deposited in well‐defined patches on the upper SiN membranes upon electron beam irradiation. The thickness of the deposits is linear with the applied electron dose. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) demonstrate that the deposited patches are a result of the merging of the original 20 nm‐diameter nanoparticles, and that the related surface roughness depends on the electron dose rate used. Using this approach, sub‐micrometer scale structures are written on the SiN in liquid by controlling the electron exposure as function of the lateral position.