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  • Catalysts and other functional materials are generally hierarchically structured materials. Hence, the detailed characterization at different length scales, and especially under reaction conditions, are necessary to unravel their mechanisms and to improve their performance and catalytic activities. Besides, a combination of several techniques is required to acquire complementary information owing to the lack of a single technique able to cover all the length scales. With respect to length, the best way to investigate is by microscopy either in 2D or more preferably in 3D. The work began with an exploration of three different 3D imaging techniques, i.e. ptychographic X-ray computed tomography, electron tomography, and focused ion beam slice-and view. Using nanoporous gold as the model, this study aimed to exhibit the versatility of 3D microscopy as a method beyond imaging as well as to confirm the necessity of complementary nature between them, where electron offers better spatial resolution and X-ray provides larger field of view. The study then continued by utilizing ptychographic X-ray computed tomography for quasi in situ thermal treatment of the same materials under atmospheric pressure. This study highlighted its ease of use of implementing in situ studies, complemented by electron tomography to prove its powerful ability to resolve what ptychographic tomography cannot. The resulting 3D volumes were then used for air permeability and CO2 diffusion simulations, along with material’s electrical and thermal conductivity simulations in order to further expose another excellent benefit from 3D microscopy. Ultimately, the work proceeded into developing two cells in order to perform full in situ investigations under controlled temperatures and atmospheres, where one cell was built for 2D only (X-ray) ptychography experiments with simultaneous X-ray fluorescence mapping, and the other was constructed with an additional capability for 3D limited-angle ptychographic tomography experiments. The feasibility tests were conducted using several functional materials, i.e. nanoporous gold, zeolite, and cobalt-manganese-oxides hollow sphere, as the models for thermal annealing process under specific atmospheres. This work eventually attests the importance of in situ studies in precisely determining the onset annealing temperatures under particular environments, to visualize the morphology online either in 2D or 3D, and to simultaneously map elemental distributions live. Moreover, a complementary technique via transmission electron microscopy was also demonstrated on the same sample, adding up another advantage in using the cells. Despite the preliminary results from in situ limited-angle ptychographic tomography experiments for limitation in data reconstruction, a new tomographic reconstruction technique was recently developed as a solution to acquire 3D images with shortened acquisition times. In conclusions, the work here converges into the ideal case of performing all-around in situ 3D imaging of functional materials for quantitative analysis and simulation.
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  • In the present era of ubiquitous digitalization, security is a concern for everyone. Despite enormous efforts, securing IT systems still remains an open challenge for community and industry. One of the main reasons is that the variety and complexity of IT systems keeps increasing, making it practically impossible for security experts to grasp the full system. A further problem is that security has become an interdisciplinary challenge. While interdisciplinary research does exist already, it is mostly restricted to collaborations between two individual disciplines and has been rather bottom-up by focusing on very specific problems. The idea of the Dagstuhl Seminar was to go one step back and to follow a comprehensive top-down approach instead. The goal was to identify the "biggest failures" in security and to get a comprehensive understanding on their overall impact on security. To this end, the Dagstuhl Seminar was roughly divided into two parts. First, experienced experts from different disciplines gave overview talks on the main problems of their field. Based on these, overlapping topics but also common research interests among the participants have been identified. Afterwards, individual working groups have been formed to work on the identified questions.
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  • Mit dem Umstieg auf erneuerbare Energien könnten künftig ganze Stadtviertel zu Selbstversorgern in Sachen Elektrizität werden. Voraussetzung: der Sonnenstrom von den Dächern des Viertels und der Strom aus lokalen Windrädern muss zwischengespeichert werden. Für die Nacht oder wenn der Wind nicht so richtig wehen will. Mit unterschiedlichen Technologien werden dafür Großspeicher entwickelt, die den Strom möglichst kostengünstig speichern sollen. Am Energy Lab des Karlsruher Instituts für Technologie werden die Stromnetze der Zukunft getestet. Im Dezember wurden dort zwei dieser Riesenbatterien in Betrieb genommen. Ziel ist es, sie unter realistischen Bedingungen zu optimieren.
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  • Different methods were applied so far in order to determine subcritical crack growth for silica. Mostly, fracture mechanics standard tests with macro cracks were used for this purpose. In this report, we evaluated the subcritical crack growth curves from lifetime tests on silica bending specimens. The survivors were then tested under increased stress. Crack growth rates down to v=10$^{-12}$m/s were reached in this way. In the plot of v=f(K/K$_{Ic}$) slight material differences could be eliminated and suitable agreement with macro-crack results by Wiederhorn and Bolz [1] on DCB-specimens and Michalske et al. [2] on DCDC-specimens could be stated.
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  • Finite element (FE) forming simulation offers the possibility of a detailed analysis of the deformation behaviour of continuously fibre-reinforced FFinite element (FE) forming simulation offers the possibility of a detailed analysis of the deformation behaviour of continuously fibre-reinforced olymers (CFRPs) during forming, in order to predict possible manufacturing effects such as wrinkling or local changes in fibre volume content. ppolymers (CFRPs) during forming, in order to predict possible manufacturing effects such as wrinkling or local changes in fibre volume content. he majority of macroscopic simulations are based on conventional two-dimensional shell elements with large aspect ratios to model the TThe majority of macroscopic simulations are based on conventional two-dimensional shell elements with large aspect ratios to model the membrane and bending behaviour of thin fibrous reinforcements efficiently. However, without a three-dimensional element approach, stresses membrane and bending behaviour of thin fibrous reinforcements efficiently. However, without a three-dimensional element approach, stresses nd strains in thickness direction cannot be modelled accurately. Commercially available linear 3D solid elements for this purpose are rarely aand strains in thickness direction cannot be modelled accurately. Commercially available linear 3D solid elements for this purpose are rarely suitable for forming simulations since they are subjected to several locking phenomena under bending deformation, especially with large aspect suitable for forming simulations since they are subjected to several locking phenomena under bending deformation, especially with large aspect ratios. To alleviate this problem, so-called solid-shell elements based on the assumed natural strain (ANS) and enhanced assumed strain (EAS) ratios. To alleviate this problem, so-called solid-shell elements based on the assumed natural strain (ANS) and enhanced assumed strain (EAS) method can be used. Therefore, a locking-free explicit reduced-integrated 8-node-hexahedron solid-shell element, based on the initial work of method can be used. Therefore, a locking-free explicit reduced-integrated 8-node-hexahedron solid-shell element, based on the initial work of Schwarze and Reese (2011), is implemented in the commercially available FE solver Abaqus. Its suitability for macroscopic modelling of the Schwarze and Reese (2011), is implemented in the commercially available FE solver Abaqus. Its suitability for macroscopic modelling of the forming behaviour of fibrous reinforcements is outlined in this work. The presented element combines the advantages of a locking-free out-of- forming behaviour of fibrous reinforcements is outlined in this work. The presented element combines the advantages of a locking-free out-ofplane deformation behaviour of conventional thin shell elements with the advantage of maintaining a fully three-dimensional material model and plane deformation behaviour of conventional thin shell elements with the advantage of maintaining a fully three-dimensional material model and geometry description.
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  • Background: The development of alternative pathways for sustainable fuel production is a crucial task for politics, industry and research, since the current use of fossil fuels contributes to resource depletion and climate change. Microalgae are a promising option, but the technology readiness level (TRL) is low and cannot compete economically with fossil fuels. Novel genetic engineering technologies are being investigated to improve productivity and reduce the cost of harvesting products extracted from or excreted by microalgae for fuel production. However, high resource efficiency and low costs alone are no guarantee that algae fuels will find their way into the market. Technologies must be accepted by the public to become valuable for society. Despite strong efforts in algae research and development, as well as political commitments at different scales to promote algae biofuels for transport sectors, little is known about public acceptance of this alternative transport fuel. Despite the advantages of algae technology, genetically engineered (GE) microalgae can be controversial in Europe due to risk perception. Therefore, the aim of this study was to investigate, for the first time, the knowledge and views of European experts and stakeholders on the conditions and requirements for acceptability of GE microalgae for next generation biofuel production. Results: The results of the survey-based study indicate that the majority of the respondents believe that GE algae biofuels could provide strong benefits compared to other fuels. The majority would choose to be final consumers of engineered algae biofuels, if there is clear evidence of their benefits and open communication of potential risks. They believe that closed production systems with high security standards and rigorous risk assessment should be applied to avoid unintended impacts on humans and nature. Some respondents, however, are not convinced about the need to alter natural occurring algae strains to increase productivity, arguing that there is a huge unexplored variety, and that the consequences of using genome editing are still unknown. Conclusions: This evaluation of the opinions held by European experts and stakeholders regarding GE algae biofuels provides valuable and differentiated insights, both for future research and for the development of feasible socio-technical algae systems for next generation biofuel production. The identified conditions and requirements for achieving public acceptability can support the (re-)design of this innovative technology and adaptation of the framework conditions towards the implementation of algae biofuels in Europe.
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