Negative Charging of Au Nanoparticles during Methanol Synthesis from CO2/H2 on a Au/ZnO Catalyst: Insights from Operando IR and Near‐Ambient‐Pressure XPS and XAS Measurements

The electronic and structural properties of Au/ZnO under industrial and idealized methanol synthesis conditions have been investigated. This was achieved by kinetic measurements in combination with time‐resolved operando infrared (DRIFTS) as well as in situ near‐ambient pressure X‐ray photoelectron spectroscopy (NAP‐XPS) and X‐ray absorption near‐edge spectroscopy (XANES) measurements at the O K‐edge together with high‐resolution electron microscopy. The adsorption of CO during the reaction revealed the presence of negatively charged Au nanoparticles/Au sites during the initial phase of the reaction. Near‐ambient‐pressure XPS and XANES demonstrate the build‐up of O vacancies during the reaction, which goes along with a substantial increase in the rate of methanol formation. The results are discussed in comparison with previous findings for Cu/ZnO and Au/ZnO catalysts.     

Pd–Cu/HOPG and Pd–Ag/HOPG Model Catalysts in CO and Methanol Oxidations at Submillibar Pressures

Kinetics and Catalysis - The regularities of formation of alloyed Pd–Cu bimetallic particles deposited on highly oriented pyrolytic graphite (HOPG) were studied by STM and...     

Dynamics of Gliding Arc Climbing in a Unipolar Jacob’s Ladder

Technical Physics - We have designed a device with a gliding unipolar arc of the Jacob’s ladder type. The dynamics of arc rising has been investigated. It is found that the arc climbs at a...     

A Nonparametric Test for the Equivalence of Populations Based on a Measure of Proximity of Samples

We propose a new measure of proximity of samples based on confidence limits for the bulk of a population constructed using order statistics. For this measure of proximity, we compute approximate confidence limits corresponding to a given significance level in the cases where the null hypothesis on the equality of hypothetical distribution functions may or may not be true. We compare this measure of proximity with the Kolmogorov–Smirnov and Wilcoxon statistics for samples from various populations. On the basis of the proposed measure of proximity, we construct a statistical test for testing the hypothesis on the equality of hypothetical distribution functions.     

A method of selecting an optimal drainage system

We consider the problem of finding the optimal dimensions of a finite system of horizontal drainage ditches. A method is proposed for solving the corresponding mathematical programming problem. An algorithm is developed for this method.Translated from Vychislitel'naya i Prikladnaya Matematika, No. 57, pp. 71–76, 1985.     

Cobalt‐Bridged Ionic Liquid Polymer on a Carbon Nanotube for Enhanced Oxygen Evolution Reaction Activity

By taking inspiration from the catalytic properties of single‐site catalysts and the enhancement of performance through ionic liquids on metal catalysts, we exploited a scalable way to place single cobalt ions on a carbon‐nanotube surface bridged by polymerized ionic liquid. Single dispersed cobalt ions coordinated by ionic liquid are used as heterogeneous catalysts for the oxygen evolution reaction (OER). Performance data reveals high activity and stable operation without chemical instability.