Search results for "INTERFACE"
showing 10 items of 2139 documents
Measurement of sulfur isotope ratios in micrometer-sized samples by NanoSIMS
2006
Abstract Sulfur isotope ratios of atmospheric aerosol particles can provide detailed information with regard to the origin and the transport of sulfur in the environment. The new Cameca NanoSIMS 50 ion microprobe technique permits analysis of individual aerosol particles with volumes down to 0.5 μm 3 and a precision for δ 34 S of 3–10‰ (2 σ ). This technique will set new standards in the analysis of isotope ratios in atmospheric aerosol. For the first time it is possible to directly compare chemical and isotopic composition of individual aerosol particles, identify internal and external mixtures and investigate reactions of anthropogenic gases with natural aerosol such as sea salt and miner…
Influence of pH and temperature on the early stage of mica alteration
2012
Mineral dissolution and precipitation reactions actively participate in controlling fluid chemistry during water–rock interaction. In this study, the changes in the biotite and muscovite basal surface nano-morphology were evaluated during interaction with fluids of different pH (pH = 1.1, 3.3 and 5.7) at different temperatures (T =2 5, 120, and 200 C). Results show that at the nanometre scale resolution of the atomic force microscope (AFM), dissolution generates etch pits with a stair-shaped pattern over the (0 0 1) surface. The flux of dissolved elements decreases when pH increases. However, at pH 5.7, a change was found in the flux after 42 h of reaction when abundant gibbsite and kaolini…
Origin of Ubiquitous Stripes at the Graphite–Water Interface
2020
The investigation of solid-liquid interfaces is pivotal for understanding processes like wetting, corrosion, and mineral dissolution and growth. The graphite-water interface constitutes a prime example for studying the water structure at a seemingly hydrophobic surface. Surprisingly, in a large number of atomic force microscopy (AFM) experiments, well-ordered stripes have been observed at the graphite-water interface. Although many groups have reported on the observation of stripes at this interface, fundamental properties and, in particular, the origin of the stripes are still under debate. Proposed origins include contamination, interplanar stacking of graphene layers, formation of methan…
Hybrid DFT calculations of the atomic and electronic structure for ABO3 perovskite (001) surfaces
2005
Abstract We present the results of first-principles calculations on two possible terminations of the (0 0 1) surfaces of SrTiO3, BaTiO3, and PbTiO3 perovskite crystals. Atomic structure and the electronic configurations were calculated for different 2D slabs, both stoichiometric and non-stoichiometric, using hybrid (B3PW) exchange-correlation technique and re-optimized basis sets of atomic (Gaussian) orbitals. Results are compared with previous calculations and available experimental data. The electronic density distribution near the surface and covalency effects are discussed in details for all three perovskites. Both SrTiO3 and BaTiO3 (0 0 1) surfaces demonstrate reduction of the optical …
Adaptive Multi-agent System Based on Wasp-Like Behaviour for the Virtual Learning Game Sotirios
2018
The aim of this paper is to propose a model for an adaptive multi-agent system based on wasp-like behaviour for dynamic allocation of puzzles and quests in the virtual learning game SOTIRIOS. This is a digital learning game integrated inside a First Person Shooter designed by the second author of this paper. The learning process is based on many puzzles hidden in the game flow. The multi-agent system is necessary to integrate a multiplayer mode into the game. The agents use wasp task allocation behaviour, combined with a model of wasp dominance hierarchy in order to create a unique multiplayer learning system, where each user has a different learning curve, based on his results. The wasp be…
ATL model checking in the cloud
2015
This paper gives an overview of our recent work on implementing a new interactive ATL model checker for verification of open systems. In verification based on model checking, we need to provide a model of the system and also write down the properties (ATL formulas) that we require the system to satisfy. Traditionally, the semantics of ATL is given in terms of concurrent game structures. In contrast to previous approaches, our tool permits an interactive design of the ATL models as state-transition graphs, and is based on client/server architecture. The server part, published as Web service in OpenShift cloud platform, embeds the core of the ATL model checker, and the client provides an intu…
Extending and validating gestUI using technical action research
2017
gestUI is a model-driven method with tool support to define custom gestures and to include gesture-based interaction in existing user software system interfaces. So far, gestUI had been limited to the definition of the same gesture catalogue for all users of the software system. In this paper, we extend gestUI to permit individual users to define their own custom gesture catalogue and redefine some custom gestures in case of difficulty in using or remembering them. After extending gestUI, we applied technical action research from the FP7 CaaS project's Capability Design Tool with the aim of assessing its acceptance in an industrial setting. We also analysed its perceived ease-of-use and use…
PACS infrastructure supporting e-learning
2011
Digital imaging is becoming predominant in radiology. This has implications for teaching support, because conventional film-based concepts are now obsolete. The IHE Teaching File and Clinical Study Export (TCE) profile provides an excellent platform to enhance PACS infrastructure with educational functionality. This can be supplemented with dedicated e-learning tools.
Energy Transfer between Surface-Immobilized Light-Harvesting Chlorophyll a/b Complex (LHCII) Studied by Surface Plasmon Field-Enhanced Fluorescence S…
2010
The major light-harvesting chlorophyll a/b complex (LHCII) of the photosynthetic apparatus in green plants can be viewed as a protein scaffold binding and positioning a large number of pigment molecules that combines rapid and efficient excitation energy transfer with effective protection of its pigments from photobleaching. These properties make LHCII potentially interesting as a light harvester (or a model thereof) in photoelectronic applications. Most of such applications would require the LHCII to be immobilized on a solid surface. In a previous study we showed the immobilization of recombinant LHCII on functionalized gold surfaces via a 6-histidine tag (His tag) in the protein moiety. …
Interfacial behavior of recombinant forms of human pulmonary surfactant protein SP-C.
2012
The behavior at air-liquid interfaces of two recombinant versions of human surfactant protein SP-C has been characterized in comparison with that of native palmitoylated SP-C purified from porcine lungs. Both native and recombinant proteins promoted interfacial adsorption of dipalmitoylphosphatidylcholine bilayers to a limited extent, but catalyzed very rapid formation of films from different lipid mixtures containing both zwitterionic and anionic phospholipids. Once at the interface, the recombinant variants exhibited compression-driven structural transitions, consistent with changes in the orientation of the deacylated N-terminal segment, which were not observed in the native protein. Com…