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RBS raw data for publication "Solid–liquid interface analysis with in‐situ Rutherford backscattering and electrochemical impedance spectroscopy " Simulation results using SIMNRA-Code also included

Solid-liquid interfaces are of crucial significance since their presence in nature is ubiquitous. They play a fundamental role in diverse fields as biology, fluid physics, radiation physics, geological and environmental research, surface science and electro-chemistry. Binnig and Rohrer (Nobel Price 1986) considered the significance of the solid-liquid interface as: "The solid-liquid interface is, in our opinion, the interface of the future." [1] Investigating phenomena at the interface of a solid and an aqueous solution, where chemical reactions, oxidation, corrosion, adhesion, dissolution and ion exchange may take place, represents a challenging task. The techniques applied should not influence any of these processes, they should be able to access the interface (through the liquid or through the solid) and simultaneously deliver quantitative information on the interface properties. A new versatile experimental setup for in-situ Rutherford backscattering spectrometry at solid-liquid interfaces enabling direct and quantitative measurements with highest sensitivity is presented [2]. An electro-chemical liquid cell with a three-electrode arrangement was mounted at the IBCs 2MV Van-de-Graaff accelerator. A thin Si3N4 window (thickness down to 150 nm) separates the vacuum of the detector chamber from the electrolyte in the cell. In a first study, we investigated the attachment of Ba onto the Si3N4 surface as a function of contact time and pH value of the electrolyte solution (see Fig. 1). From these measurements, we can deduce the evolution of the double layer with sub-monolayer sensitivity in a direct and quantitative manner. Despite focusing on a particular system as presented here, the setup allows to conduct a large variety of in-situ investigations at solid-liquid interfaces such as monitoring of electro-chemical reactions, segregation, adsorption, dissolution and corrosion processes. Details of the setup, its capabilities and limitations are presented and the results of first measurements are discussed in detail. [1] G. Binnig and H. Rohrer, Reviews of Modern Physics 71 (1999), 324. [2] N. B. Khojasteh, S. Apelt, U. Bergmann, S. Facsko and R. Heller, Review of Scientific Instruments (2019), submitted.

A setup for in-situ Rutherford Backscattering Spectrometry (RBS) has been installed at the 2 MV Van-de-Graaff accelerator at the Ion Beam Center (IBC) of the Helmholtz-Zentrum Dresden-Rossendorf (HZDR). Online analysis of solid-liquid interfaces as well as electro-chemistry experiments are conducted by this technique. A Si3N4 window separates the liquid from the vacuum in the RBS chamber. A He+ beam (E = 1.7 MeV) is utilized for the RBS measurements. RBS as well as Particle Induced X-Ray Emission Spectroscopy (PIXE) spectra are recorded simultaneously to increase the sensitivity for trace elements. The technique was employed for direct measurements of the Electric-Double-Layer (EDL) formation on Si3N4. Investigations of the EDL formation at solid-liquid interfaces are of great significance due to the various valuable applications such as super-capacitors that can be utilized to provide a backup power supply or applied in various other fields [1-3]. In our preliminary experiments, the specific adsorption of Barium ions from a 1mM BaCl2 solution with various pH values was observed in a direct and quantitative manner. Sensitivity of the technique reaches the ppm range and areal densities can be measured down to 0.1 atomic monolayer. [1]Kötz et al., (2002). The 12th International Seminar on Double Layer Capacitors and Similar Energy Storage Devices, Dec, USA. [2]Faggioli et al., (1999). J. Power Sources, 84(2): 261. [3]Simon et al., (2008). Nature materials, 7(11): 845.

Education in architecture requires access to a broad range of learning materials, so as to develop flexibility and creativity in design. The learning material is comprised of textual and visual media including images, videos, descriptions of architectural concepts or projects, i.e. digital artifacts on different aggregation levels. Until now, repositories storing such information have not been interrelated and have not provided unified access. Consequently, finding and retrieving architectural learning objects is cumbersome and time consuming. In this paper, we describe how an infrastructure of federated architectural learning repositories will provide unique, integrated access facilities for high quality architectural content. The integration of various types of content, usage, social and contextual metadata enables users to develop multiple perspectives and navigation paths that support experience multiplication for the user. A standards–based, service– oriented software architecture, and flexible user interface design solutions, based on embeddable widgets, ensure easy integration and re-combinability of contents, metadata and functionalities. ispartof: pages:22-49 ispartof: Browsing Architecture: Metadata and Beyond pages:22-49 ispartof: International Conference on Online Repositories in Architecture location:Venice, Italy date:20 Sep - 21 Sep 2008 status: published

FILLER SYSTEMS. Depending on their type and structure, the fillers in a plastic compound give rise to different conductivities. In the case of polyamide, in particular, this conductivity is also affected by the moisture content Special investigations consider the phenomena of electrical conductivity and look into the possibility of using the corresponding polyamide 66 compounds for bipolar plates in a fuel cell.