BINA

The seawater electrolysis is an economically favorable approach for water splitting application because seawater is one of the plentiful abundant natural resources on our earth. In water splitting pathway, the anodic half-cell reaction from seawater stills a challenging task due to anodic corrosion and the competitive chloride oxidation process. In the current study, we prepared flower-shaped porous nanorods of iron doped cobalt nickel layered double hydroxide supported on nickel foam (Fe0.05 CoNi LDH/NF), which require very less oxygen evolution reaction (OER) overpotential in 1M KOH (212 mV) and alkaline seawater (287 mV) to deliver 10 mAcm−2 current density and exhibited remarkable 14 h durability. At the same time, post treated sample reveals the better OER activity after chronopotentiometry analysis, because of superior conductivity and corrosion-resistance of the electrocatalyst. The doping of Fe …

Quantum many-body systems are emerging as key elements in the quest for quantum-based technologies and in the study of fundamental physics. In this context, finding control protocols that allow for fast and high fidelity evolutions across quantum phase transitions is of particular interest. Ideally, such controls should be scalable with the system size and not require controllable and unwanted extra interactions. In addition, its performance should be robust against potential imperfections. Here we design an invariant-based control technique that ensures perfect adiabatic-like evolution in the lowest energy subspace of the many-body system, and is able to meet all these requirements -- tuning the controllable parameter according to the analytical control results in high-fidelity evolutions operating close to the speed limit, valid for any number particles. As such, Kibble-Zurek scaling laws break down, leading to tunable and much better time scaling behavior. We illustrate our findings by means of detailed numerical simulations in the transverse-field Ising and long-range Kitaev models and demonstrate the robustness against noisy controls and disorder.

Nanometric fillers are known to affect the electrochemical performance of polymer electrolytes. Here, nanowires and nanotubes of TiO 2 with the same crystal structure are compared as additives to poly (ethylene oxide) based electrolytes for solid state sodium batteries. Electrochemical studies of symmetric cells with blocking and non-blocking electrodes examined the effects of the additive shapes on the bulk electrolyte and Na-electrolyte interface. Impedance spectroscopy was used as a major electroanalytical tool. To obtain a full perspective, all-solid-state batteries were evaluated. In galvanostatic measurements the filler shape effect is most noticeable at a high current density. TiO 2 nanotubes improve the solid electrolyte behavior considerably more than titania nanowires. This effect is related mainly to the interface of the polymeric matrix with the electrodes.

Lead-acid systems dominate the global market owing to simple technology, easy fabrication, availability, and mature recycling processes. However, the sulfation of negative lead electrodes in lead-acid batteries limits its performance to less than 1000 cycles in heavy-duty applications. Incorporating activated carbons, carbon nanotubes, graphite, and other allotropes of carbon and compositing carbon with metal oxides into the negative active material significantly improves the overall health of lead-acid batteries. Carbons play a vital role in advancing the properties of lead-acid batteries for various applications, including deep depth of discharge cycling, partial state-of-charge, and high-rate partial state-of-charge cycling. Therefore, lead-carbon hybrid batteries and supercapacitor systems have been developed to enhance energy-power density and cycle life. This review article provides an overview of lead-acid …

In a recent work, we have shown that photon absorption can cause a chemical bond to be created between the two monomers within a protonated serine dimer, a process known as intra-cluster bond formation (ICBF), despite this process not occurring following thermal excitation via low energy collision-induced dissociation (LE-CID). Here we show further evidence for non-statistical photon-induced dissociation (PID) of the protonated serine dimer. In addition we discuss LE-CID and PID studies of the protonated serine octamer, showing that in this case as well, PID leads to non-statistical fragmentation and to the formation of two bonds between three neighboring monomers.

Raman spectroscopy in transition metal dichalcogenides (TMDCs) helps determine their structural information and layer dependency. Because it is non‐destructive and fast, it is an archetypal spectroscopic technique to investigate the structure and defects in TMDCs. In our earlier study, we used a metal‐dielectric coating to enhance Raman signal of WS2 because the Raman Spectra measured from WS2 coated on the standard Si/SiO2 was significantly lower. This metal‐dielectric coating allowed access to the otherwise unavailable E12g and A1g modes of WS2. In this study, we compare the Raman spectra of WS2 on a Si/SiO2 to that of metal layers (Au [200 nm] and Al [200 nm]). A significant enhancement in the Raman signal of 2‐3L WS2 is observed for both the Au and Al coatings. Although 200 nm Au coating enhances the Raman Signal better than the 10 nm Au coating, it does not resolve the other …

The development of platinum group metal-free catalysts is considered the most prominent path for reducing the cost of low-temperature fuel cells (LTFC). Despite the great advancement in the field, its further progress is currently limited by the ability to understand and mitigate the catalysts’ degradation mechanisms, which up to recent years was limited by the lack of activity descriptors. Recent work showed that this could be solved using Fourier-transformed alternating current voltammetry that enables to deconvolute Faradaic currents arising from the redox reaction of the active sites from the capacitive currents, and by that accurately measure the electrochemically active site density of these catalysts in situ fuel cells. However, the analysis of the results can be complex, requiring simulation software for accurate parameter extraction. Herein, a simplified analysis of Fourier-transformed alternating current voltammetry is …

The transition from dissolution-precipitation to quasi-solid-state sulfur reaction promises restricted polysulfide shuttle and lean electrolyte operation of Li-S batteries but incurs poor reaction kinetics. We here demonstrate that structural reorganization of sparingly solvating electrolytes (SSEs)—which is uniquely afforded by using low-density and low-cost aromatic anti-solvents—is vital for taming the quasi-solid-state sulfur reaction. Aromatic anti-solvents disrupt the interconnected structure of concentrated tetrahydrofuran (THF) electrolyte, uniquely creating subdomains that act to dissolve elemental sulfur, thus accelerating its consumption and re-formation while maintaining ultralow polysulfides solubility. The altered subdomains further result in robust solid electrolyte interphase (SEI) on lithium metal. As a result, the Li-S cell with a 3 mgsulfur cm−2 sulfur cathode can cycle steadily for ∼160 cycles with a lean …

We report the observation of coherent oscillations in conversion efficiency of molecules formed from a thermal gas of ultracold atoms. Finite thermal energy of the gas causes loss of coherence when a broad continuum is resonantly coupled to a discrete bound state. Restoration of the coherence can be achieved through non-adiabatic transitions of the dressed molecular energy level that are induced by a strong modulation pulse with fast envelope dynamics. Conditions to observe coherent oscillations are verified, and control of their properties is demonstrated. The main experimental findings are supported by theoretical modeling and numerical calculations.

Nanoporous gold (Au) films are self-supported structures that possess a large surface area and extraordinary catalytic activity. Generally, nanoporous gold is obtained by solution-based dealloying where the less noble metal, often silver (Ag), is etched out. However, the residual amounts of the sacrificial metal are not well controlled, the impure samples show restructuring, and the residual metal prevents the study of the catalytic role of Au alone. Here, we fabricate impurity-free nanoporous gold films by a plasma-enabled dry synthetic route. The scheme does not include sacrificial metals or solution processing and is much more general. It is used to obtain self-supported ultra-pure nanoporous gold films with controllable pore sizes. The impurity-free nanoporous gold films possess highly curved ligaments, are remarkably robust, and stable over hundreds of electrochemical cycles. Furthermore, they contain many …

Fermi liquids respond differently to perturbations depending on whether their frequency is higher (collisionless regime) or lower (hydrodynamic regime) than the interparticle collision rate. This results in a different phase velocity between the collisionless zero sound and the hydrodynamic first sound. We performed terahertz photocurrent nanoscopy measurements on graphene devices, with a metallic gate close to the graphene layer, to probe the dispersion of propagating acoustic plasmons, the counterpart of sound modes in electronic Fermi liquids. We report the observation of a change in the plasmon phase velocity when the excitation frequency approaches the electron-electron collision rate that is compatible with the transition between the zero and the first sound mode.

In this short review paper, relative evolution in time and related issues are analyzed within classical and quantum mechanics. We first discuss the basics of quantum frames of reference in both space and time. We then focus on the latter, and more specifically on the “timeless” approach to quantum mechanics due to Page and Wootters. We address time–energy uncertainty relations and the emergence of non-unitarity within this framework. We emphasize relational aspects of quantum time as well as unique features of non-inertial clock frames.

Oil‐in‐water emulsion droplets spontaneously adopt, below some temperature Td, counterintuitive faceted and complex non‐spherical shapes while remaining liquid. This transition is driven by a crystalline monolayer formed at the droplets' surface. Here, we show that ppm‐level doping of the droplet's bulk by long‐chain alcohols allows tuning Td by >50 °C, implying formation of drastically different interfacial structures. Furthermore, “magic” alcohol chain lengths maximize Td. This we show to arise from self‐assembly of mixed alcohol:alkane interfacial structures of stacked alkane layers, co‐crystallized with hydrogen‐bonded alcohol dimers. These structures are accounted for theoretically and resolved by direct cryogenic transmission electron microscopy (cryoTEM), confirming the proposed structures. The discovered tunability of key properties of commonly‐used emulsions by minute concentrations of specific bulk …

In this work, we report a pixel reassignment based super-resolution reconstruction algorithm for structured illumination microscopy (entitled PR-SIM). PR-SIM provides a twofold theoretical resolution enhancement by reassigning the pixels in raw SIM images with respect to the center of each illumination fringe and applying further deconvolution. By comparing with frequency domain based algorithms, PR-SIM is more immune to fringe distortion and, hence, it is more suited for large-field SIM in that it processes the raw images locally. Meanwhile, the reconstruction speed of PR-SIM can be enhanced by skipping empty regions in the image and further enhanced by employing GPU-base parallel calculation. Overall, we can envisage that the PR-SIM can be extended for other illumination modulation based microscopic techniques.

Magneto-optical imaging was employed to study dendritic flux avalanches in metal/superconductor and superconductor/superconductor hybrid structures over an extended range of magnetic field ramping rates. Our results in Cu/NbN show that the previously reported suppression of dendritic flux avalanches in metal coated superconducting films is limited to low ramping rates; as the ramping rate increases, the metal coating becomes less and less effective. A more complex behavior is exhibited in superconductor/superconductor hybrid structures. Our measurement in NbN partially coated with Nb, reveal three distinctive types of dendritic avalanches: those propagating in only one layer, either as regular dendrites in the uncoated NbN or as surface dendrites in the Nb layer, and hybrid dendrites that propagate in both the Nb and NbN layers simultaneously. These three types of dendrites are distinguished by their …

The need for new, reliable, and sustainable energy sources led to the development of new types of fuel cells. Fuel cells that rely on liquid hydrogen carriers may be the ultimate solution to the expensive hydrogen logistics issues. In this category, direct quinone fuel cells (DQFCs) are a promising new technology that solves many of the issues of traditional fuel cells. As a new technology, DQFCs need to be studied thoroughly to reach their full potential. Here, we use a distribution of relaxation times (DRT) analysis to analyze the impedance data of DQFCs, to gain a better understanding of the system. We systematically changed the operating parameters and attributed the changes in the DRT spectra to the physical processes they correspond to. The four main peaks observed in the DRT measurements were assigned to oxygen reduction reaction (ORR), quinone diffusion resistance, proton diffusion in the membrane …

SignificanceDiabetes is a prevalent disease worldwide that can cause severe health problems. Accurate blood glucose detection is crucial for diabetes management, and noninvasive methods can be more convenient and less painful than traditional finger-prick methods.AimWe aim to report a noncontact speckle-based blood glucose measurement system that utilizes artificial intelligence (AI) data processing to improve glucose detection accuracy. The study also explores the influence of an alternating current (AC) induced magnetic field on the sensitivity and selectivity of blood glucose detection.ApproachThe proposed blood glucose sensor consists of a digital camera, an AC-generated magnetic field source, a laser illuminating the subject’s finger, and a computer. A magnetic field is applied to the finger, and a camera records the speckle patterns generated by the laser light reflected from the finger. The acquired …

Chemical pollutants in drinking water can have many sources, such as pharmaceutical waste, agricultural runoff, and industrial discharges1, 2, 3. The development of a reliable, sensitive, and handheld sensor for the detection of a mixture of contaminants is important, both for human health and the environment. Herein, we show the development of a plasmonic sensor for Surface-enhanced Raman spectroscopy (SERS) and colorimetry measurements. Two types of plasmonic surfaces which enhance the electromagnetic field are presented here;(i) Well-defined cavities milled in silver substrates which are covered with 5 nm of SiO2 for stability.(ii) A scalable metallic-like aerogel network with large surface area, for increasing the sensitivity of our measurements. Three different families of analytes were studied, which can be found in drinking water: Piperidine and its derivatives (Pharmaceutical waste), Dioxins & Polychlorinated biphenyls, Per-and polyfluoroalkyl substances, each of which is toxic, both to the environment and humans health, even at a low concentration of 30 mg/Kg (3* 10-4M). Those

The allocation of CPU time and memory resources, are well known problems in organizations with a large number of users, and a single mainframe. Usually, the amount of resources given to a single user is based on its own statistics, not on the entire statistics of the organization therefore patterns are not well identified and the allocation system is prodigal. In this work the authors suggest a fuzzy logic-based algorithm to optimize the CPU and memory distribution between the users based on the history of the users. The algorithm works separately on heavy users and light users since they have different patterns to be observed. The result is a set of rules, generated by the fuzzy logic inference engine that will allow the system to use its computing ability in an optimized manner. Test results on data taken from the Faculty of Engineering in Tel Aviv University, demonstrate the abilities of the new algorithm. This paper also …

Hydrogen production via water electrolysis defines the novel energy vector for achieving a sustainable society. However, the true progress of the given technology is hindered by the sluggish and complex hydrogen evolution reaction (HER) occurring at the cathodic side of the system where overpriced and scarce Pt-based electrocatalysts are usually employed. Therefore, efficient platinum group metals (PGMs)-free electrocatalysts to carry out HER with accelerated kinetics are urgently demanded. In this scenario, molybdenum disulfide (MoS2) owing to efficacious structural attributes and optimum hydrogen-binding free energy (ΔGH*) is emerging as a reliable alternative to PGMs. However, the performance of MoS2-based electrocatalysts is still far away from the benchmark performance. The HER activity of MoS2 can be improved by engineering the structural parameters i.e., doping, defects inducement, modulating …

Efimov states are exotic and counterintuitive three-body quantum states that emerge in the vicinity of two-atom Feshbach resonances. These states exhibit remarkable characteristics as their large spatial extent and extremely weak binding energies following an infinite geometric series, and exist even when interactions are not strong enough to bind two atoms. Efimov states are universal and produce observable effects at critical values of the interaction strength across the two-body resonance when approaching their threshold for dissociation into the different types of three-body continua. In particular, as the strength of the interaction is decreased, an Efimov state merges into the atom-dimer threshold and eventually dissociates into an unbound atom-dimer pair. Here we explore this critical point using refined coherent few-body spectroscopy in Li atoms near a narrow two-body Feshbach resonance. Contrary to the expectation set by universality, we find that the Li Efimov trimer does not immediately dissociate when passing the threshold, and survives as a metastable state embedded in the atom-dimer continuum. We identify this behavior with a novel phenomena related to the emergence of a repulsive interaction in the atom-dimer channel which reshapes the three-body interactions in systems characterized by narrow Feshbach resonances. Our results shed new light on the nature of Li Efimov states and provide a new path to understand various puzzling phenomena observed here, as well as in other previous experimental studies.