The influence of crystallographic orientation on the wetting of silicon on quartz single crystals

Dynamic hexagonal spreading patterns of small silicon droplets on the basal plane (001) of quartz were observed by video microscopy. A detailed analysis of the hexagonal triple line demonstrates that the patterns show slight chiral distortions that can be attributed to the screw axis of the substrate crystal. This article reveals the detailed influence of crystal symmetry on the anisotropy of reactive wetting. In this context, a first discussion about the interplay of wetting and etching of a crystal is provided

Energetics of Technical Integration of 2‐Propanol Fuel Cells: Thermodynamic and Current and Future Technical Feasibility

2-Propanol/acetone is a promising liquid organic hydrogen carrier system for fuelcell reactions. Herein, six different concepts for a 2-propanol/acetone fuel cellsystem are evaluated in MATLAB simulation with respect to their thermodynamicintegration and technical feasibility. Four of the concepts use a direct 2-propanolfuel cell while the other two first release molecular hydrogen from 2-propanol andsubsequently use a hydrogen fuel cell. The presented liquid phase 2-propanol fuelcell concept is thermodynamically feasible but cannot be realized technicallyusing commercial Nafion membranes, due to membrane dissolution by the2-propanol/acetone/water fuel mixture. Gaseous 2-propanol fuel cells imply a highheating requirement for the evaporation of the fuel. A direct high-temperature fuelcell using 2-propanol is thermodynamically feasible because there is less water inthe overall system but is not technically feasible because of the esterification ofphosphoric acid. A very interesting option is the conversion of gaseous 2-propanolto pressurized hydrogen in an electrochemical pumping step followed by ahydrogen fuel cell, because here the waste heat of a sufficiently hot hydrogen fuelcell can drive the 2-propanol evaporation

Surface Chemistry of the Molecular Solar Thermal Energy Storage System 2,3-Dicyano-Norbornadiene/Quadricyclane on Ni(111)

Molecular solar thermal (MOST) systems are a promising approach for the introduction of sustainable energy storage solutions. We investigated the feasibility of the dicyano-substituted norbornadiene/quadricyclane molecule pair on Ni(111) for catalytic model studies. This derivatization is known to lead to a desired bathochromic shift of the absorption maximum of the parent compound. In our experiments further favorable properties were found: At low temperatures, both molecules adsorb intact without any dissociation. In situ temperature-programmed HR-XPS experiments reveal the conversion of (CN)2-quadricyclane to (CN)2-norbornadiene under energy release between 175 and 260 K. The absence of other surface species due to side reactions indicates full isomerization. Further heating leads to the decomposition of the molecular framework into smaller carbonaceous fragments above 290 K and finally to amorphous structures, carbide and nitride above 400 K. DFT calculations gave insights into the adsorption geometries. (CN)2-norbornadiene is expected to interact stronger with the surface, with flat configurations being favorable. (CN)2-quadricyclane exhibits smaller adsorption energies with negligible differences for flat and side-on geometries. Simulated XP spectra are in good agreement with experimental findings further supporting the specific spectroscopic fingerprints for both valence isomers

Berlin Paris-konform machen

BERLIN PARIS-KONFORM MACHEN Berlin Paris-konform machen / Hirschl, Bernd (Rights reserved) ( -

Influence of Auditory Cues on the Neuronal Response to Naturalistic Visual Stimuli in a Virtual Reality Setting

Virtual reality environments offer great opportunities to study the performance of brain-computer interfaces (BCIs) in real-world contexts. As real-world stimuli are typically multimodal, their neuronal integration elicits complex response patterns. To investigate the effect of additional auditory cues on the processing of visual information, we used virtual reality to mimic safety-related events in an industrial environment while we concomitantly recorded electroencephalography (EEG) signals. We simulated a box traveling on a conveyor belt system where two types of stimuli – an exploding and a burning box – interrupt regular operation. The recordings from 16 subjects were divided into two subsets, a visual-only and an audio-visual experiment. In the visual-only experiment, the response patterns for both stimuli elicited a similar pattern – a visual evoked potential (VEP) followed by an event-related potential (ERP) over the occipital-parietal lobe. Moreover, we found the perceived severity of the event to be reflected in the signal amplitude. Interestingly, the additional auditory cues had a twofold effect on the previous findings: The P1 component was significantly suppressed in the case of the exploding box stimulus, whereas the N2c showed an enhancement for the burning box stimulus. This result highlights the impact of multisensory integration on the performance of realistic BCI applications. Indeed, we observed alterations in the offline classification accuracy for a detection task based on a mixed feature extraction (variance, power spectral density, and discrete wavelet transform) and a support vector machine classifier. In the case of the explosion, the accuracy slightly decreased by –1.64% p. in an audio-visual experiment compared to the visual-only. Contrarily, the classification accuracy for the burning box increased by 5.58% p. when additional auditory cues were present. Hence, we conclude, that especially in challenging detection tasks, it is favorable to consider the potential of multisensory integration when BCIs are supposed to operate under (multimodal) real-world conditions

Rail2X - SmartServices (Projektabschlussbericht)

V2X (Vehicle2Everything) ist ein WLAN-ähnlicher Standard, der im Automobilbereich für den Informationsaustausch zwischen Fahrzeugen und / oder Infrastruktur genutzt wird. Beispiels-weise findet dieser Nachrichtenstandard im Straßenverkehr Anwendung, um den Autofahrer rechtzeitig vor kritischen Situationen zu warnen und so zu unterstützen. V2X-Komponenten befinden sich daher seit mehreren Jahren in der Entwicklung und Erpro-bung. Jedoch ist dieser Kommunikationsstandard nicht ausschließlich auf den Automobilbe-reich begrenzt, sondern verkehrsträgerunabhängig ausgelegt. Über das Projekt Rail2X-Smart Services wurde die Nutzung der V2X-Kommunikation für den Eisenbahnsektor evaluiert. Ziel des Projektkonsortiums war die Erforschung und Erweiterung von V2X als Rail2X in den Bahnbereich, um den Komfort sowie die Effektivität und Wirtschaftlichkeit des Bahnbetriebs im Regionalverkehr zu steigern. Grundsätzlich wurde ein Verkehrsträger und Verkehrsmittel übergreifender Informationsaustausch ermöglicht. Sowohl die Nutzung einheitlicher Standards als auch die Verknüpfung mit einem zentralen Datenmanagementsystem, das Daten bearbeitet und mit anderen Datenquellen wie der mCLOUD korreliert, spielten dabei eine zentrale Rolle. Für die Erprobung und Evaluierung wurden drei relevanten Anwendungsfällen im Bahnbereich definiert und ausgestaltet die durch die V2X-Anwendung einen wirtschaftlichen Betrieb ermöglichen. Mittels dieser Anwendungsfälle konnte gezeigt werden, dass einerseits die Nutzung des V2X-Standards möglich und andererseits die Anwendung von kostengünstigen Standardkomponenten aus dem Automobilbereich auch im Bahnbereich zielführend ist

Mobility in a Globalised World 2017

The term mobility has different meanings in the following science disciplines. In economics, mobility is the ability of an individual or a group to improve their eco-nomic status in relation to income and wealth within their lifetime or between gen-erations. In information systems and computer science, mobility is used for the concept of mobile computing, in which a computer is transported by a person dur-ing normal use. Logistics creates by the design of logistics networks the infrastruc-ture for the mobility of people and goods. Electric mobility is one of today’s solu-tions from an engineering perspective to reduce the need of energy resources and environmental impact. Moreover, for urban planning, mobility is the crunch ques-tion about how to optimise the different needs for mobility and how to link differ-ent transportation systems. In this publication we collected the ideas of practitioners, researchers, and gov-ernment officials regarding the different modes of mobility in a globalised world, focusing on both domestic and international issues