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Production of C-2/C-3 Oxygenates from Planar Copper Nitride-Derived Mesoporous Copper via Electrochemical Reduction of CO2
Electrochemical reduction of CO2 provides an opportunity to produce fuels and chemicals in a carbon-neutral manner, assuming that CO2 can be captured from the atmosphere. To do so requires efficient, selective, and stable catalysts. In this study, we report a highly mesoporous metallic Cu catalyst prepared by electrochemical reduction of thermally nitrided Cu foil. Under aqueous saturated CO2 reduction conditions, the Cu3N-derived Cu electrocatalyst produces virtually no CH4, very little CO, and exhibits a faradaic efficiency of 68% in C2+ products (C2H4, C2H5OH, and C3H7OH) at a current density of ∼18.5 mA cm-2 and a cathode potential of -1.0 V versus the reversible hydrogen electrode. Under these conditions, the catalyst produces more oxygenated products than hydrocarbons. We show that surface roughness is a good descriptor of catalytic performance. The roughest surface reached 98% CO utilization efficiency for C2+ product formation from CO2 reduction and the ratio of oxygenated to hydrocarbon products correlates with the degree of surface roughness. These effects of surface roughness are attributed to the high population of undercoordinated sites as well as a high pH environment within the mesopores and adjacent to the surface of the catalyst
High-Fidelity Control, Detection, and Entanglement of Alkaline-Earth Rydberg Atoms
Trapped neutral atoms have become a prominent platform for quantum science, where entanglement fidelity records have been set using highly excited Rydberg states. However, controlled two-qubit entanglement generation has so far been limited to alkali species, leaving the exploitation of more complex electronic structures as an open frontier that could lead to improved fidelities and fundamentally different applications such as quantum-enhanced optical clocks. Here, we demonstrate a novel approach utilizing the two-valence electron structure of individual alkaline-earth Rydberg atoms. We find fidelities for Rydberg state detection, single-atom Rabi operations and two-atom entanglement that surpass previously published values. Our results pave the way for novel applications, including programmable quantum metrology and hybrid atom–ion systems, and set the stage for alkaline-earth based quantum computing architectures
Packet transmission optimisation using Genetic Algorithms
A Genetic Algorithm (ga) is used to optimise the parameters for a sequence of packets sent over the Internet. Only the parameters
that a client machine can change are used and the fitness is based on the
delay time returned by the Traceroute program. The ga performance is
compared to a fixed packet size with no priority used to assess the status
of the network. The ga generally performed to the same level as the
control settings but in some cases significant improvements were made
Low intensity shockwave treatment modulates macrophage functions beneficial to healing chronic wounds
Acknowledgments: We acknowledge the University of Aberdeen Microscopy and Histology Facility and the qPCR facility for use of facilities and advice. We acknowledge Ehab Husain for scoring the patient wound biopsies. Funding: This research was funded by NHS Grampian Endowments, grant number 17/004 and by personal funding from JSH.Peer reviewedPublisher PD
Uranium(III) coordination chemistry and oxidation in a flexible small-cavity macrocycle
U(III) complexes of the conformationally flexible, small-cavity macrocycle trans-calix[2]benzene[2]pyrrolide (L)2–, [U(L)X] (X = O-2,6-tBu2C6H3, N(SiMe3)2), have been synthesized from [U(L)BH4] and structurally characterized. These complexes show binding of the U(III) center in the bis(arene) pocket of the macrocycle, which flexes to accommodate the increase in the steric bulk of X, resulting in long U–X bonds to the ancillary ligands. Oxidation to the cationic U(IV) complex [U(L)X][B(C6F5)4] (X = BH4) results in ligand rearrangement to bind the smaller, harder cation in the bis(pyrrolide) pocket, in a conformation that has not been previously observed for (L)2–, with X located between the two ligand arene rings
High-Fidelity Control, Detection, and Entanglement of Alkaline-Earth Rydberg Atoms
Trapped neutral atoms have become a prominent platform for quantum science, where entanglement fidelity records have been set using highly excited Rydberg states. However, controlled two-qubit entanglement generation has so far been limited to alkali species, leaving the exploitation of more complex electronic structures as an open frontier that could lead to improved fidelities and fundamentally different applications such as quantum-enhanced optical clocks. Here, we demonstrate a novel approach utilizing the two-valence electron structure of individual alkaline-earth Rydberg atoms. We find fidelities for Rydberg state detection, single-atom Rabi operations and two-atom entanglement that surpass previously published values. Our results pave the way for novel applications, including programmable quantum metrology and hybrid atom–ion systems, and set the stage for alkaline-earth based quantum computing architectures
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