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Advanced in situ X-ray absorption spectroscopy characterization ofelectrochemically co-electrodeposited bi-element copper alloy electrodesshows that zinc yields the formation of a stable cationic Cu species during theelectroreduction of CO2 at high cathodic polarization. In contrast, theformation/stabilization of cationic Cu species in copper oxides, or doping Cuwith another element, like Ni, is not possible. It is found that the pure andmixed Cu:Zn electrodes behave similarly in term of electrocatalytic selectivityto multi-carbon products. At higher Zn concentrations the electrode behaveslike the pure Zn catalyst, which indicates that the Cu cationic species do nothave a significant influence on the selectivity to multi-carbon products. It isfound that in the non-monotonically distribution of products is dominated interm of surface energy in which copper prefers the surface. Otherwise, thiswork highlights the importance of in situ characterization to uncover themechanisms mediating the catalytic reactions in contrast to ex situ or postmortem analysis, which can be a source of misinterpretation.

Rational innovation of electrocatalysts requires detailed knowledge of spatial property variations across the solid-electrolyte interface. We introduce correlative atomic force microscopy (AFM) to simultaneously probe, in situ and at the nanoscale, electrical conductivity, chemical-frictional, and morphological properties of a bimetallic copper-gold system for CO2 electroreduction. In air, water, and bicarbonate electrolyte, current-voltage curves reveal resistive CuOx islands in line with local current contrasts, while frictional imaging indicates qualitative variations in the hydration layer molecular ordering upon change from water to electrolyte. Nanoscale current contrast on polycrystalline Au shows resistive grain boundaries and electrocatalytically passive adlayer regions. In situ conductive AFM imaging in water shows mesoscale regions of low current and reveals that reduced interfacial electric currents are accompanied by increased friction forces, thus indicating variations in the interfacial molecular ordering affected by the electrolyte composition and ionic species. These findings provide insights into how local electrochemical environments and adsorbed species affect interfacial charge transfer processes and support building in situ structure-property relationships in catalysis and energy conversion research.

Catalyst restructuring during electrochemical reactions is a critical but poorly understood process that determines the underlying structure–property relationships during catalysis. In the electrocatalytic reduction of CO2 (CO2RR), it is known that Cu, the most favorable catalyst for hydrocarbon generation, is highly susceptible to restructuring in the presence of halides. Iodide ions, in particular, greatly improved the catalyst performance of Cu foils, although a detailed understanding of the morphological evolution induced by iodide remains lacking. It is also unclear if a similar enhancement transfers to catalyst particles. Here, we first demonstrate that iodide pre-treatment improves the selectivity of hexagonally ordered Cu-island arrays towards ethylene and oxygenate products. Then, the morphological changes in these arrays caused by iodide treatment and during CO2RR are visualized using electrochemical transmission electron microscopy. Our observations reveal that the Cu islands evolve into tetrahedral CuI, which then become 3-dimensional chains of copper nanoparticles under CO2RR conditions. Furthermore, CuI and Cu2O particles re-precipitated when the samples are returned to open circuit potential, implying that iodide and Cu+ species are present within these chains. This work provides detailed insight into the role of iodide, and its impact on the prevailing morphologies that exist during CO2RR.

Conventionally a mobility edge (ME) marks a critical energy that separates two different transport zones where all states are extended and localized, respectively. Here we propose a novel quasiperiodic spin-orbit coupled lattice model with experimental feasibility to realize a fundamentally new quantum phase with three coexisting energy-dependent zones, i.e., the extended, critical and localized zones, and uncover the underlying generic mechanism for the occurrence of the new quantum phase. Accordingly, this phase exhibits new types of MEs which separate the extended states from critical ones, and the localized states from critical ones, respectively. We introduce the diagnostic quantities to characterize and distinguish the different zones, and show that the predicted phase can be detected by measuring the fractal dimension or conductivities. The experimental realization is also proposed and studied. This work extends the concept of ME and enriches the quantum phases in disordered systems, which sheds light on searching for new localization and critical phenomena with novel transport and thermoelectric effects.

Catalyst restructuring during electrochemical reactions is a critical but poorly understood process that determines the underlying structure-property relationships during catalysis. In the electrocatalytic reduction of CO

Fracton topological order (FTO) is a new classification of correlated phases in three spatial dimensions with topological ground state degeneracy (GSD) scaling up with system size, and fractional excitations which are immobile or have restricted mobility. With the topological origin of GSD, FTO is immune to local perturbations, whereas a strong enough global external perturbation is expected to break the order. The critical point of the topological transition is however very challenging to identify. In this work, we propose to characterize quantum phase transition of the type-I FTOs induced by external terms and develop a theory to study analytically the critical point of the transition. In particular, for the external perturbation term creating lineon-type excitations, we predict a generic formula for the critical point of the quantum phase transition, characterized by the breaking-down of GSD. This theory applies to a board class of FTOs, including X-cube model, and for more generic FTO models under perturbations creating two-dimensional (2D) or 3D excitations, we predict the upper and lower limits of the critical point. Our work makes a step in characterizing analytically the quantum phase transition of generic fracton orders., 11 pages + 17 pages Supplementary Material. Important updates have been made for the exact results of critical points

Almandine garnet is used commonly in abrasive blasting processes to prepare metallic surfaces for painting. However, there is evidence that the process leads to significant amounts of abrasive embedded in the “cleaned” surface, and hence the surface chemistry of garnet will affect the binding of any coatings subsequently applied. In addition, in marine environments seawater aerosol droplets are expected to impact the exposed surface prior to coating application, depositing both water and dissolved inorganic ions. In this work, we provide indepth analysis of the chemistry of the almandine garnet surface using angle-resolved X-ray photoelectron spectroscopy (XPS) and note a correlation for several elemental oxides between literature values of the binding energy of the surface oxygen 1s XPS peak and the basicity of the hydroxyl group that forms on the surface. We also consider the adsorption to almandine garnet powder of seawater-relevant inorganic ions (sodium, magnesium, and calcium): Binding constants have been determined using titration measurements, solution-depletion isotherms, and numerical modeling, with calcium observed to bind more strongly than magnesium. The relevance of Langmuir-type fits to constant-pH adsorption isotherms is discussed. By contrast, sodium either binds very weakly or is effectively inert toward the garnet surface under the experimental conditions. The complex adsorption behavior observed emphasizes the necessity of using multiple techniques to characterize mineral surfaces.

Photoelectrochemical devices integrate the processes of light absorption, charge separation, and catalysis for chemical synthesis. The monolithic design is interesting for space applications, where weight and volume constraints predominate. Hindered gas bubble desorption and the lack of macroconvection processes in reduced gravitation, however, limit its application in space. Physico-chemical modifications of the electrode surface are required to induce gas bubble desorption and ensure continuous device operation. A detailed investigation of the electrocatalyst nanostructure design for light-assisted hydrogen production in microgravity environment is described. p-InP coated with a rhodium (Rh) electrocatalyst layer fabricated by shadow nanosphere lithography is used as a model device. Rh is deposited via physical vapor deposition (PVD) or photoelectrodeposition through a mask of polystyrene (PS) particles. It is observed that the PS sphere size and electrocatalyst deposition technique alter the electrode surface wettability significantly, controlling hydrogen gas bubble detachment and photocurrent–voltage characteristics. The highest, most stable current density of 37.8 mA cm−2 is achieved by depositing Rh via PVD through 784 nm sized PS particles. The increased hydrophilicity of the photoelectrode results in small gas bubble contact angles and weak frictional forces at the solid–gas interface which cause enhanced gas bubble detachment and enhanced device efficiency.

Symmetry-protected topological superconductors (TSCs) can host multiple Majorana zero modes (MZMs) at their edges or vortex cores, while whether the Majorana braiding in such systems is non-Abelian in general remains an open question. Here we uncover in theory the unitary symmetry-protected non-Abelian statisitcs of MZMs and propose the experimental realization. We show that braiding two vortices with each hosting $N$ unitary symmetry-protected MZMs generically reduces to $N$ independent sectors, with each sector braiding two different Majorana modes. This renders the unitary symmetry-protected non-Abelian statistics. As a concrete example, we demonstrate the proposed non-Abelian statistics in a spin-triplet TSC which hosts two MZMs at each vortex and, interestingly, can be precisely mapped to a quantum anomalous Hall insulator. Thus the unitary symmetry-protected non-Abelian statistics can be verified in the latter insulating phase, with the application to realizing various topological quantum gates being studied. Finally, we propose a novel experimental scheme to realize the present study in an optical Raman lattice. Our work opens a new route for Majorana-based topological quantum computation., Comment: Main text (5+pages, 4 figures) and Supplementary Material (5+pages, 2 figures); Discussions and refs are updated

Background Distracted driving has become alarmingly widespread, and its prevalence continues to increase despite efforts by government and nongovernment organizations to educate the public about this pervasive problem. Every year, 1.35 million people die, and nearly 80 million people get injured in road traffic incidents. Motor vehicle crashes are the leading cause of death among young people, and distracted driving plays a huge role in road traffic fatalities and injuries. Considering that most people now use the internet as an information source and Google is the most visited website and number one online search engine in the world, we performed a qualitative analysis of information available through Google on distracted driving and its outcomes. Objective The goal of this study was to analyze the quality and accuracy of the information on distracted driving and its consequences available to the general public when using Google as a search engine for distracted driving. Methods In November 2018, a nonregional Google search on distracted driving was conducted. The first two pages of the Google search results were selected for analysis. Data were collected on the type of website, type of distraction, consequences of distracted driving described, presence and referencing of statistics, and orthopedic and nonorthopedic injuries described, with their acute and chronic sequelae. Results In total, we analyzed 25 websites: 12 websites (48%) were from government bodies, which were the most common type of websites; 19 (76%) of the sites provided statistics; and 15 (60%) referenced the source of the statistic. Mobile phones were the most frequently cited type of distraction, with 17 (68%) sites discussing it, while death was the most commonly mentioned consequence of distracted driving, quoted in 15 (60%) of the websites. Additionally, 52% of the sites provided tips on how to avoid distracted driving. Only one website mentioned orthopedic injuries. Conclusions The prevalence of distracted driving is increasing, and so are the consequences associated with it. Nevertheless, the information available online does not accurately describe the current circumstances regarding this issue. The National Highway Traffic Safety Administration attributed 391,000 injuries and 3477 deaths to distracted driving in 2015, which are 5000 more injuries and almost 150 more fatalities compared to 2011. However, despite these figures, most of the websites discussed death as a consequence of distracted driving and often overlooked injuries, even though injuries are over 100 times more likely to occur in distraction-affected crashes. The websites also largely fail to address other forms of driving distractions, like daydreaming or talking to a passenger, and mostly focus on mobile phone–related activities as distractions. More specific information on the dangers of distracted driving and nonlethal trauma may support an overall cultural shift to curb this behavior.

BACKGROUND Distracted driving has become alarmingly widespread, and its prevalence continues to increase despite efforts by government and nongovernment organizations to educate the public about this pervasive problem. Every year, 1.35 million people die, and nearly 80 million people get injured in road traffic incidents. Motor vehicle crashes are the leading cause of death among young people, and distracted driving plays a huge role in road traffic fatalities and injuries. Considering that most people now use the internet as an information source and Google is the most visited website and number one online search engine in the world, we performed a qualitative analysis of information available through Google on distracted driving and its outcomes. OBJECTIVE The goal of this study was to analyze the quality and accuracy of the information on distracted driving and its consequences available to the general public when using Google as a search engine for distracted driving. METHODS In November 2018, a nonregional Google search on distracted driving was conducted. The first two pages of the Google search results were selected for analysis. Data were collected on the type of website, type of distraction, consequences of distracted driving described, presence and referencing of statistics, and orthopedic and nonorthopedic injuries described, with their acute and chronic sequelae. RESULTS In total, we analyzed 25 websites: 12 websites (48%) were from government bodies, which were the most common type of websites; 19 (76%) of the sites provided statistics; and 15 (60%) referenced the source of the statistic. Mobile phones were the most frequently cited type of distraction, with 17 (68%) sites discussing it, while death was the most commonly mentioned consequence of distracted driving, quoted in 15 (60%) of the websites. Additionally, 52% of the sites provided tips on how to avoid distracted driving. Only one website mentioned orthopedic injuries. CONCLUSIONS The prevalence of distracted driving is increasing, and so are the consequences associated with it. Nevertheless, the information available online does not accurately describe the current circumstances regarding this issue. The National Highway Traffic Safety Administration attributed 391,000 injuries and 3477 deaths to distracted driving in 2015, which are 5000 more injuries and almost 150 more fatalities compared to 2011. However, despite these figures, most of the websites discussed death as a consequence of distracted driving and often overlooked injuries, even though injuries are over 100 times more likely to occur in distraction-affected crashes. The websites also largely fail to address other forms of driving distractions, like daydreaming or talking to a passenger, and mostly focus on mobile phone–related activities as distractions. More specific information on the dangers of distracted driving and nonlethal trauma may support an overall cultural shift to curb this behavior.

Bis(2-ethylhexyl) phosphate (BEHP) was exposed to carbon steel surfaces from dry and water-saturated dodecane. The resulting changes to the surfaces were characterised using spectroscopic techniques (energy dispersive X-ray (EDX), X-ray photoelectron (XPS), and far-infrared reflection absorption (RAIRS) spectroscopies) and polarised neutron reflectometry (PNR). Although there was no observable affinity of BEHP to the steel surface in dry solvent, a layer of rough iron (III) phosphate formed in water-saturated dodecane. The phosphate-reacted steel surface showed some resistance to corrosion by seawater, suggesting the formation of a cohesive barrier against corrosive species. The results support the use of BEHP as an anti-corrosion additive and a viable phosphating agent for steel surfaces.

This work reports that abrasive blasting of a structural steel results in significant retention of garnet abrasive residues. A comparative study of the adsorption behavior of a number of organic species, relevant to paint components and additives, onto the surfaces of garnet and S355 steel from nonaqueous solutions is also presented. Areas per adsorbed molecule, estimated from the isotherm data, suggest a range of molecular orientations on the surfaces. Pronounced differences in the adsorption strength to the garnet and steel were observed, particularly that most additives bind more strongly to steel than to garnet. Surface characterization data from acid-base titrations, photoelectron spectroscopy, and backscattered electron diffraction were used to rationalize the adsorption data obtained. The ramifications of these findings for particular industrial processes, with regards the strength of paint adhesion and paint additive formulations, are highlighted.

The corrosive breakdown of thin iron films supported on silicon substrates under a number of conditions is presented—in particular to understand better how iron, and hence ferritic steel, behaves in a salty water environment. A combination of X-ray and neutron reflectometry was used to monitor the structures of both the metal and oxide surface layers and also organic corrosion inhibitors adsorbed at the iron/aqueous interface. A range of behaviour in seawater was observed, including complete dissolution and void formation under the metal surface. Importantly, two simple treatments—UV/ozone or soaking in ultrapure water—were found to significantly protect the iron surface for considerable lengths of time, although evidence of pitting corrosion began after around 10 days. The underlying causes of the efficacies of these treatments were further investigated using X-ray photoelectron spectroscopy. In addition, three potential corrosion inhibitors were investigated: (i) dodecyltrimethylammonium bromide (DTAB) demonstrated no ability to protect the surface; (ii) sodium dodecyl sulfate (SDS) appeared to accelerate corrosion; (iii) bis(2-ethylhexyl)phosphate showed an impressive level of protection (the neutron reflectometry results indicated a thick diffuse layer of surfactant of 23 % surface coverage). These findings have been interpreted in terms of preferential inhibitor adsorption at cathodic and anodic surface sites (depending on the nature of the inhibitor).

It is well known that non-Abelian Majorana zero modes (MZM) harbor at vortex cores in a $p_{x}+\text{i}p_{y}$ topological superconductor, which can be realized in a 2D spin-orbit coupled system with a single Fermi surface and by proximity coupling to an $s$-wave superconductor. Here we show that existence of non-Abelian MZMs is unrelated to the bulk topology of a 2D superconductor, and propose that such exotic modes can be resulted in much broader range of superconductors, being topological or trivial. For a generic 2D system with multiple Fermi surfaces and gapped out by superconducting pairings, we show that at least a single MZM survives if there are only odd number of Fermi surfaces of which the corresponding superconducting orders have vortices, and such MZM is protected by an emergent Chern-Simons invariant, irrespective of the bulk topology of the superconductor. This result may enrich new experimental schemes for realizing non-Aelian MZMs. In particular, we propose a minimal scheme to realize the MZMs in a 2D superconducting Dirac semimetal with trivial bulk topology, which can be well achieved based on the recent cold atom experiments., 5 pages, 3 figures, plus Supplementary Material

Objectives To compare long-term health outcome of Sanders type IV calcaneal fractures treated with open reduction and internal fixation (ORIF) versus ORIF plus primary subtalar arthrodesis (PSTA). Design Randomized prospective multicenter trial. Setting Four Level 1 trauma hospitals in Canada. Patients Thirty-one patients with 31 Sanders IV displaced intraarticular calcaneal fractures. Intervention Seventeen patients were treated with a standard protocol involving a lateral approach for ORIF. Fourteen patients were treated with a standard protocol involving a lateral approach with ORIF + PSTA. Main outcome measurements Health outcomes were assessed with 4 validated instruments: (1) the Short Form 36 version 2 (SF-36), (2) the Musculoskeletal Functional Assessment Survey, (3) the American Orthopaedic Foot and Ankle Society's Ankle-Hindfoot Scale, and (4) the Visual Analogue Scale. Results From 2004 to 2011, 26 patients (26 displaced intraarticular calcaneal fractures) were followed for a minimum of 2 years (81% follow-up). No statistical difference was found between the results for ORIF compared with ORIF + PSTA: the mean SF-36 physical component scores were, respectively, 30.2 (SD = 11.4) and 37.8 (SD = 10.4) (P = 0.10); the mean Musculoskeletal Functional Assessment Survey scores were 44.2 (SD = 25.6) and 37.9 (SD = 21.5) (P = 0.50); the mean Ankle-Hindfoot Scale scores were 62.5 (SD = 19.6) and 65.8 (SD = 19.2), (P = 0.68); and the mean Visual Analogue Scale scores were 36.8 (SD = 34.7) and 36.0 (SD = 30.7) (P = 0.82). Conclusions We were unable to demonstrate a significant difference between treating Sanders type IV fractures with either ORIF or ORIF + PSTA. It remains the choice of the surgeon and patient to take into account patient specific factors to determine treatment. However, ORIF + PSTA may be advantageous for both patients with Sanders type IV fractures and the health care system as patients heal quickly. Furthermore, ORIF + PSTA may prevent the need for late secondary subtalar fusion adding to increased costs and lost time from work. Level of evidence Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

The recent realization of two-dimensional (2D) synthetic spin-orbit (SO) coupling opens a broad avenue to study novel topological states for ultracold atoms. Here, we propose a new scheme to realize exotic chiral Fulde-Ferrell superfluid for ultracold fermions, with a generic theory being shown that the topology of superfluid pairing phases can be determined from the normal states. The main findings are two fold. First, a semimetal is driven by a new type of 2D SO coupling whose realization is even simpler than the recent experiment, and can be tuned into massive Dirac fermion phases with or without inversion symmetry. Without inversion symmetry the superfluid phase with nonzero pairing momentum is favored under an attractive interaction. Furthermore, we show a fundamental theorem that the topology of a 2D chiral superfluid can be uniquely determined from the unpaired normal states, with which the topological chiral Fulde-Ferrell superfluid with a broad topological region is predicted for the present system. This generic theorem is also useful for condensed matter physics and material science in search for new topological superconductors., 4 figures, 5 pages + Supplemenrary Material. Figures are updated, typos are corrected

Topologically protected states are observed in engineered optical lattices with ultracold fermions., Symmetry plays a fundamental role in understanding complex quantum matter, particularly in classifying topological quantum phases, which have attracted great interests in the recent decade. An outstanding example is the time-reversal invariant topological insulator, a symmetry-protected topological (SPT) phase in the symplectic class of the Altland-Zirnbauer classification. We report the observation for ultracold atoms of a noninteracting SPT band in a one-dimensional optical lattice and study quench dynamics between topologically distinct regimes. The observed SPT band can be protected by a magnetic group and a nonlocal chiral symmetry, with the band topology being measured via Bloch states at symmetric momenta. The topology also resides in far-from-equilibrium spin dynamics, which are predicted and observed in experiment to exhibit qualitatively distinct behaviors in quenching to trivial and nontrivial regimes, revealing two fundamental types of spin-relaxation dynamics related to bulk topology. This work opens the way to expanding the scope of SPT physics with ultracold atoms and studying nonequilibrium quantum dynamics in these exotic systems.

The voltammetric behavior of glassy carbon electrodes modified with either submonolayer quantities of alumina or graphene is examined with respect to the two-electron, two-proton reaction of catechol (1,2-dihydroxybenzene) in aqueous solution. While the voltammetric behavior superficially hints at a change of electron transfer rate, an alternative explanation in terms of the changed thermodynamics of the intermediate species is advanced and rationalized.

Spin-orbit-coupled bosons can exhibit rich equilibrium phases at low temperature and in the presence of particle-particle interactions. In the case with a 1D synthetic spin-orbit interaction, it has been observed that the ground state of a Bose gas can be a normal phase, stripe phase, or magnetized phase in different parameter regimes. The magnetized states are doubly degenerate and consist of a many-particle two-state system. In this work, we investigate the nonequilibrium quantum dynamics by switching on a simple one-dimensional optical lattice potential as external perturbation to induce resonant couplings between the magnetized phases, and predict a quantum spin dynamics which cannot be obtained in the single-particle systems. In particular, due to particle-particle interactions, the transition of the Bose condensate from one magnetized phase to the other is forbidden when the external perturbation strength is less than a critical value, and a full transition can occur only when the perturbation exceeds such critical strength. This phenomenon manifests itself a dynamical phase transition, with the order parameter defined by the time-averaged magnetization over an oscillation period, and the critical point behavior being exactly solvable. The thermal fluctuations are also considered in detail. From numerical simulations and exact analytic studies we show that the predicted many-body effects can be well observed with the current experiments.

Despite extensive work on the controlled surface modification of carbon with redox moieties, to date almost all available methodologies involve complex chemistry and are prone to the formation of polymerized multi-layer surface structures. Herein, the facile bifunctional redox tagging of carbon nanoparticles (diameter 27 nm) and its characterization is undertaken using the industrial dye Reactive Blue 2. The modification route is demonstrated to be via exceptionally strong physisorption. The modified carbon is found to exhibit both well-defined oxidative and reductive voltammetric redox features which are quantitatively interpreted. The method provides a generic approach to monolayer modifications of carbon and carbon nanoparticle surfaces.

Well-defined poly((furfuryl glycidyl ether)-co-(glycidyl methyl ether) carbonate) (P((FGE-co-GME)C)) copolymers with varying furfuryl glycidyl ether (FGE) content in the range of 26% to 100% are prepared directly from CO2 and the respective epoxides in a solvent-free synthesis. All materials are characterized by size-exclusion chromatography (SEC), (1)H NMR spectroscopy, and differential scanning calorimetry (DSC). The furfuryl-functional samples exhibit monomodal molecular weight distributions with Mw/Mn in the range of 1.16 to 1.43 and molecular weights (Mn) between 2300 and 4300 g mol(-1). Thermal properties reflect the amorphous structure of the polymers. Both post-functionalization and cross-linking are performed via Diels-Alder chemistry using maleimide derivatives, leading to reversible network formation. This transformation is shown to be thermally reversible at 110 °C.