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Der Antwortpsalm – ein Kind der Liturgiereform des Zweiten Vatikanischen Konzils – vereinigt in sich mehrere zentrale Anliegen der Reform und wird dadurch zum Gradmesser für dessen Umsetzung. Er macht den „Tisch des Wortes Gottes“ reichhaltiger. Er zeigt, dass das Singen wesentlich zur Feier der Liturgie gehört. Er ermöglicht eine zugleich persönliche und gemeinschaftliche Teilnahme aller an der Liturgie. Er trägt zur Vielfalt liturgischer Dienste bei durch den Einsatz eines Psalmisten (oder Kantors). Er vereinigt in sich die drei Schritte des liturgischen Dialogs: hören – bedenken – antworten.

In order to gain a systematic understanding of electrode/electrolyte interface between gold electrodes and ionic liquids, the adsorption of 1-butyl-3-methyl-imidazolium-hexafluorophosphate (BMI/PF $$_6$$ ) on Au(100) was determined for a wide range of surface coverages using density functional theory (DFT) calculations. At low coverages BMI is exceptionally mobile (translational and rotational barriers of $$

Constrained ab initio thermodynamics in the form of a Pourbaix diagram can greatly assist kinetic modeling of a particular electrochemical reaction such as the chlorine evolution reaction (CER) over RuO 2 (110). Pourbaix diagrams reveal stable surface structures, as a function of pH and the potential. The present DFT study indicates that the Pourbaix diagram in the CER potential region above 1.36 V and pH values around zero is dominated by a stable surface structure in which all coordinatively undercoordinated Ru sites (Ru cus ) are capped by on-top oxygen (O ot ). This oxygen saturated RuO 2 (110) surface is considered to serve as the catalytically active phase in the CER, quite in contrast to the heterogeneously catalyzed HCl oxidation (Deacon process), for which the active RuO 2 (110) surface is mainly covered by on-top chlorine. The active sites in the CER are suggested to be Ru cus O ot surface complexes, while in the Deacon process both undercoordinated surface Ru and oxygen sites must be available for the activation of HCl molecules.

The numerical and experimental investigation of non-axisymmetric casing treatments is complex compared to axisymmetric ones like circumferential grooves. Hence they are still rarely investigated, at least regarding combinations of numerical and experimental work on the same configuration. The casing treatment under investigation is capable of significantly broadening the operating range of a tip-critical transonic compressor. This is accomplished without an efficiency penalty at design conditions. It is demonstrated that the application of a casing treatment over the rotor might impose negative effects on the downstream stator that would have to be considered in future designs. Earlier work by the authors was focused on the experimental investigation, in particular of transient effects near stall. In this paper, RANS and URANS simulations are presented in detail. These are used to further study and explain the causes of the effects that were found experimentally. Additional experimental data are added where appropriate, continuing the validation of the numerical methods.

In the industrially important Chlor-Alkali process, the chlorine evolution reaction (CER) over a ruthenium dioxide (RuO2) catalyst competes with the oxygen evolution reaction (OER). This selectivity issue is elucidated on the microscopic level with the single-crystalline model electrode RuO2(110) by employing density functional theory (DFT) calculations in combination with the concept of volcano plots. We demonstrate that one monolayer of TiO2(110) supported on RuO2(110) enhances the selectivity towards the CER by several orders of magnitudes, while preserving the high activity for the CER. This win-win situation is attributed to the different slopes of the volcano curves for the CER and OER.

The first extraction of graphene in 2004 led to a wide range of experimental and theoretical studies aimed at better understanding and exploiting the unique properties of this novel two-dimensional material. Among the many potential applications, which have been suggested, are uses of graphene as a substrate in high-performance catalysis and as a component in circuit-board technology. In particular, graphene s high surface area and conductivity have motivated proposals to use it as a substrate for growing and/or anchoring metal nanoparticles in high-performance catalysts and other electrochemical devices. However, the activity of such carbon-supported metal catalysts is strongly dependent on the dispersion and stability of the metal clusters on the support (i.e. the ability of the substrate to stabilize metal clusters of various sizes on its surface). Thus, vacancy defects are expected to play a vital role in making graphene suitable for these applications by supplying highly active binding sites for adsorbing and stabilizing metal clusters. Indeed, finite populations of single and double vacancy defects are thermodynamically stable in graphene, and have been studied extensively. Density functional theory (DFT) calculations revealed that vacancy defects resulting from the removal of up to five C atoms reconstruct to form non-hexagonal rings (models are shown in the Supporting Information: Figures S1.b–f). Even larger holes have been observed in electron microscopy experiments. Defects may also play a critical role in using graphene components for circuit fabrication. For example, taking advantage of the Dirac fermions in graphene requires opening up its band gap to convert it from a conductor into a semiconductor. This conversion can be achieved by doping graphene with either B or N atoms; however, another possibility for accomplishing this could be the adsorption of small metal clusters on the surface. Because the adsorption of such clusters can be used to tune additional magnetic and transport properties of the substrate, it might also provide a technique for controlling an additional set of electromagnetic properties. The catalytic nature of Ni is well established, and Ni nanoparticles are commonly used to catalyze the synthesis of carbon nanostructures. Owing to the strong affinity between Ni and C, the incorporation of Ni atoms into carbon nanostructures, grown using Ni catalysts, has been observed. Ushiro et al. reported that X-ray adsorption measurements detect Ni impurities in carbon nanostructures following nickel-catalyzed synthesis, which even treatment with acid is not able to remove. Moreover, Banhart et al. identified Ni impurities wrapped in onion-like graphenic particles by using electron microscopy. The work of Rinaldi et al. is even more supportive. Combining results from DFT calculations and high-resolution transmission electron microcopy measurements (HR-TEM) utilizing several in situ characterization techniques, they concluded that Ni atoms form very stable Ni– C compounds during nickel-catalyzed carbon nanotube (CNT) growth, which are incorporated into the final products. They also found unexpectedly strong adsorption of the Ni clusters on the CNT supports. However, despite the potential advantages of using Ni nanoparticles adsorbed on graphene, their catalytic and electromagnetic properties (with the exception of single and two Ni atoms adsorbates) remain mostly unexplored. Based on these findings, it would be expected that just as Ni nanoparticles might be used to tailor critical properties of defective graphene sheets, a graphene substrate might be used to modify the catalytic properties of nickel nanoparticles as well. To elucidate this potential interplay we employ DFT to study the adsorption of Nin nanoclusters on defective graphene (details in the Supporting Information). As substrate models we select graphene sheets with vacancy defects, resulting from the removal of x atoms (with x 5; see Figure S1 in the Supporting Information). To model the adsorbed Ni nanoparticles, we successively grew Nin clusters with n 10 and focused on the lowest energy adsorption configuration of each Nin cluster on each of these six graphene substrates (with and without vacancy defects). The binding energies (referenced against single Ni atoms and the graphene substrate) for the lowest energy configuration are summarized in Figure 1. The binding energies can be explained by three types of bond contributions. The first type of binding is between Ni atoms. As the cluster size increases the ratio of bulk to surface atoms increases so that the binding energy will asymptotically [*] Dr. W. Gao, Dr. J. E. Mueller, Dr. J. Anton, Prof. Dr. T. Jacob Institut f r Elektrochemie, Universit t Ulm 89081 Ulm (Germany) E-mail: timo.jacob@uni-ulm.de

Using density functional theory and thermodynamic considerations, adsorbate-induced faceting of high-index metal surfaces such as Ir(210) and Re(112 1) has been studied. Focusing on these two systems we first discuss the adsorption behaviour of oxygen and nitrogen on the various surfaces relevant for the faceting, and afterwards use these energies to evaluate the stability of substrates and facets in the presence of oxygen and nitrogen. The faceting phase diagrams of Ir(210) and Re(112 1) show that both adsorbates enhance the anisotropy in surface free energy, finally causing nanofacets to become the thermodynamically favourable surface structure. We also generated analogous electrochemical phase diagrams for both surfaces in contact with an oxygen- or nitrogen-containing electrolyte and found that the same nanofacets should also become stable at positive electrode potentials. Thus, our calculations not only reproduce the experimentally observed surface faceting under UHV conditions, but also predict facet formation under electrochemical conditions.

The amount of tritium activity in labeled histological sections mounted on slides can be measured in a liquid szintillation spectrometer. An efficiency of about 20% is obtained, dependence on section thickness (tested on 3 μ, 5 μ, and 10 μ, sections) does not exist. After washing out the szintillation fluid autoradiography and staining of the sections as usual is possible.