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International audience; Metal oxides are important functional materials with a wide range of applications, especially in the field of electrocatalysis. However, quick and accurate assessment of their real electroactive surface area (ECSA), which is of paramount importance for the evaluation of their performance, remains a challenging task. In the presentation, I will present a relatively simple strategy for an accurate in situdetermination of the ECSA of commonly used metal oxide catalysts, namely: Ni-, Co-, Fe-, Pt-and Ir-based oxides. Similar to the well-established practice in electrocatalysis, the method is based on the phenomenon of specific adsorption. It uses the fact that,at the electrode potentials close to the onset of the oxygen evolution reaction (OER), specifically adsorbed reaction intermediates manifest themselves through so-called adsorption capacitance, which is unambiguously detectable using electrochemical impedance spectroscopy.[1,2] With simple impedance measurements, experimentalists can acquire the adsorption capacitance values and accurately estimate the real electroactive surface area of the above-mentioned oxide materials, including nanostructured electrocatalysts. Additionally, as illustrative examples, I will demonstrate an application of the method for the determination of the ECSA of oxide catalyst nanoparticles.

The Swiss Young Neurosurgeons Society (SYNS) comes to life in 2008, creating a community renowned for its unique spirit, a platform dedicated to lifelong teaching and learning. In 2008, a small group of Swiss residents found a cross-canton training platform to provide dedicated, affordable courses organized by residents to directly support their peers. After almost 10 years, SYNS thrives on its unique, familial spirit cultivating a direct contact with teachers as well as with their supporters. The society provides up to four annual training courses and serves as an open platform for residents to exchange experiences and to represent their members&rsquo, interests on a national and international level.

Objective: Higher accuracy rates of image-guided pedicle screw placement compared to freehand placement in the thoracolumbar spine has been proven in the literature. Image-guidance in spine surgery has increased significantly during the past decade; however, there is a lack of data concerning the impact[for full text, please go to the a.m. URL], 68. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), 7. Joint Meeting mit der Society of British Neurological Surgeons (SBNS)

A major shift toward passively managed index funds in recent years has led to the re-concentration of corporate ownership in the hands of just three large asset management firms, the Big Three: BlackRock, Vanguard and State Street. We propose that this trend has re-structured ownership in capital markets. Adopting a contractual view to the corporate share, we re-define share holding and suggest that the New Mandate Owners in fact hold the essence of corporate power, as their aggregated positions capture the core element of the franchise of corporate voting.

33rd European Photovoltaic Solar Energy Conference and Exhibition; 610-612, APCVD (atmospheric pressure chemical vapor deposition) offers promising improvements for the PERT (passivated emitter rear totally diffused) solar cell concept. One-sided diffusion of P as well as B allows reduced processing steps. In this work the gettering efficacy of P- and B-doped layers deposited by APCVD on mc (multicrystalline) Si (silicon) material is evaluated by minority charge carrier lifetime measurements. Comparison with the influence of thermal load showed that P-gettering resulted in significant lifetime increase, whereas temperature treatment without PSG (phosphor silicate glass) induced the opposed effect. Close to the crucible wall, the local defect structure in the wafer leads in ungettered samples to negative effects that can be strongly reduced by P-gettering. In addition, the APCVD PSG layers showed at least comparable gettering efficacy to standard POCl3-gettering via diffusion in a quartz tube furnace. Finally, co-diffusion of APCVD PSG and BSG layers was tested for a PERT concept.