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Organisationseinheit der BAM
To start the large-scale deployment of offshore wind in German waters, the German Federal Ministry for the Environment (BMU) supports the offshore test site "alpha ventus" in the North Sea with a research budget of about 50 million Euro in the next years. The overall objective of the research is to reduce the costs of offshore wind energy deployment in deep water. In order to provide all participating research projects with detailed data, the test site will be equipped with extensive measurement instrumentation.
This research initiative was named RAVE Research at Alpha VEntus and consists of a variety of projects in connection with the installation and operation of alpha ventus. As part of the RAVE initiative, so far the participating institutes and companies have prepared projects on the following topics:
Realization of the joint measurements and data management
Analysis of loads, modelling and further development of the different components of offshore wind turbines
Loads at offshore foundations and structures
Further development of LIDAR wind measuring techniques
Grid integration of offshore wind energy
Monitoring of the offshore wind energy deployment in Germany "Offshore WMEP"
Measurement of the operating noises and modelling of the sound propagation between tower and water
Ecologic research
Assessment of existing steel structures - Recommendations for estimation of remaining fatigue life
(2008)
With rare exceptions, natural evolution is an extremely slow process. One particularly striking exception in the case of protein evolution is in the natural production of antibodies. Developing B cells activate and diversify their immunoglobulin (Ig) genes by recombination, gene conversion (GC) and somatic hypermutation (SHM). Iterative cycles of hypermutation and selection continue until antibodies of high antigen binding specificity emerge (affinity maturation). The avian B cell line DT40, a cell line which is highly amenable to genetic manipulation and exhibits a high rate of targeted integration, utilizes both GC and SHM. Targeting the DT40's diversification machinery onto transgenes of interest inserted into the Ig loci and coupling selective pressure based on the desired outcome mimics evolution. Here we further demonstrate the usefulness of this platform technology by selectively pressuring a large shift in the spectral properties of the fluorescent protein eqFP615 into the highly stable and advanced optical imaging expediting fluorescent protein Amrose. The method is advantageous as it is time and cost effective and no prior knowledge of the outcome protein's structure is necessary. Amrose was evolved to have high excitation at 633 nm and excitation/emission into the far-red, which is optimal for whole-body and deep tissue imaging as we demonstrate in the zebrafish and mouse model.
Ergot alkaloids are mycotoxins formed by fungi of the Claviceps genus, which are some of the most common contaminants of food and feed worldwide. These toxins are a structurally heterogeneous group of compounds, sharing an ergoline backbone. Six structures and their corresponding stereoisomers are typically quantified by either HPLC-FLD or HPLC-MS/MS and the values subsequently summed up to determine the total ergot alkaloid content. For the development of a screening method targeting all ergot alkaloids simultaneously, the alkaloids need to be transferred to one homogeneous structure: a lysergic acid derivative. In this study, two promising cleaving methods—acidic esterification and hydrazinolysis—are compared, using dihydroergocristine as a model compound. While the acidic esterification proved to be unsuitable, due to long reaction times and oxidation sensitivity, hydrazinolysis reached a quantitative yield in 40-60 min. Parallel workup of several samples is possible. An increasing effect on the reaction rate by the addition of ammonium iodide was demonstrated. Application of hydrazinolysis to a major ergot alkaloid mix solution showed that all ergopeptines were cleaved, but ergometrine/-inine was barely affected. Still, hydrazinolysis is a suitable tool for the development of a sum parameter screening method for ergot alkaloids in food and feed.
The low-cycle fatigue behavior of cc-brass CuZn30 was irtvestigated in uniaxial (tension-compression and torional) and biaxial tests under total strain control at room temperature. Planar-biaxial fatigue tests were carried out on a servohydraulic tension-compression testing machine with and without phase shift using a cruciform specimen geometry with fixed principal stress axes. In phase and out of phase tensiontorsion tests were performed using tube shape specimens on a servohydraulic tensiontorsion testing machine. Microstructural investigations were performed by transmission electron microscopy as well as by scanning electron microscope. For all proportional load cases the equivalent strain amplitude based on a maximum shear strain energy criterion results in a similar hardening behavior and in fatigue life times within a scatter band of three. Out of phase loading results in additional cyclic hardening and reduced life time. Planar glide structures were observed in all tested cases as well as areas of pronounced strain localization in the torsional load cases. No evidence of transition to wavy glide behavior was observed.
For the assessment of the barrier function of the geosphere around a nuclear waste repository information about the nature of the accessible rock pore space and internal surfaces is needed. Intact samples of various types of fresh and altered crystalline rocks have been studied by means of mercury intrusion porosimetry and gas adsorption methods using various adsorbates. Furthermore, fluorescence microscopy and scanning electron microscopy was applied and the results were compared with those of impregnation with carbon-l4-polymethylmethacrylate (PMMA). Additional structural information was derived from hydraulic conductivity determinations using helium gas.
The investigations were focussed on the reliability of these measurements of intact core samples, the influence of rock composition, structure and geological evolution on the microstructure of the matrices and the consequences regarding the retardation properties of the bedrock.