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Oct 2022 • ACS Applied Materials & Interfaces

Unique Mechanisms of Ion Storage in Polyaniline Electrodes for Pseudocapacitive Energy Storage Devices Unraveled by EQCM-D Analysis

Meital Turgeman, Gil Bergman, Amey Nimkar, Bar Gavriel, Elad Ballas, Fyodor Malchik, Mikhael D Levi, Daniel Sharon, Netanel Shpigel, Doron Aurbach

The optimal performance of organic electrodes for aqueous batteries requires their full compatibility with selected electrolyte solutions. Electrode materials having 1–3-dimensional structures of variable rigidity possess a confined space in their structure filled with water and electrolyte solutions. Depending on the rigidity and confined space geometry, insertion and extraction of ions into electrode structures are often coupled with incorporation/withdrawal of water molecules. Aside from the scientific interest in understanding the charging mechanism of such systems, co-insertion of solvent molecules affects strongly the charge storage capability of the electrodes for energy storage devices. We present herein in situ electrochemical quartz crystal microbalance with dissipation monitoring (EQCM-D) investigations of polyaniline (PANI) electrodes operating in various aqueous Na+-containing electrolytes, namely, Na2SO4 …

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Oct 2022 • Talanta

High throughput optical modulation biosensing for highly sensitive and rapid detection of biomarkers

Shmuel Burg, Shira Roth, Meir Cohen, Shira Avivi-Mintz, Michael Margulis, Hanan Rohana, Avi Peretz, Amos Danielli

Rapid, highly sensitive, and high-throughput detection of biomarkers at low concentrations is invaluable for early diagnosis of various diseases. In many highly sensitive immunoassays, magnetic beads are used to capture fluorescently labeled target molecules. The target molecules are then quantified by detecting the fluorescent signal from individual beads, which is time consuming and requires a complicated and expensive detection system. Here, we demonstrate a high-throughput optical modulation biosensing (ht-OMB) system, which uses a small permanent magnet to aggregate the beads into a small detection volume and eliminates background noise by steering a laser beam in and out of the cluster of beads. Shortening the aggregation, acquisition, and well-to-well scanning transition times enables reading a 96-well plate within 10 min. Using the ht-OMB system to detect human Interleukin-8, we …

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Oct 2022 • Communications biology

Affinity microfluidics enables high-throughput protein degradation analysis in cell-free extracts

Lev Brio, Danit Wasserman, Efrat Michaely-Barbiro, Gal Barazany-Gal, Doron Gerber, Amit Tzur

Protein degradation mediated by the ubiquitin-proteasome pathway regulates signaling events in many physiological and pathological conditions. In vitro degradation assays have been instrumental in the understanding of how cell proliferation and other fundamental cellular processes are regulated. These assays are direct, time-specific and highly informative but also laborious, typically relying on low-throughput polyacrylamide gel-electrophoresis followed by autoradiography or immunoblotting. We present protein degradation on chip (pDOC), a MITOMI-based integrated microfluidic technology for discovery and analysis of proteins degradation in cell-free extracts. The platform accommodates hundreds of microchambers on which protein degradation is assayed quickly, simultaneously and using minute amounts of reagents in one or many physiochemical environments. Essentially, pDOC provides a sensitive …

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Oct 2022 • Journal of Personalized Medicine

Trace Elements in Tears: Comparison of Rural and Urban Populations Using Particle Induced X-ray Emission

Olga Girshevitz, Noa Cohen-Sinai, Alon Zahavi, Yoav Vardizer, Dror Fixler, Nitza Goldenberg-Cohen

We aimed to evaluate the types and concentrations of trace elements in tears of individuals living in urban and rural environments using particle induced X-ray emission (PIXE) and the possible association with exposure to air pollution and suggest a novel method for tear-based biomonitoring studies. This cross-sectional pilot study comprised 42 healthy subjects, 28 living in a rural area and 14 in an industrial city. Tears were collected with Schirmer paper and characterized by PIXE. Trace element concentrations from both eyes were averaged together with environmental pollution data. Main outcome measures were between-group differences in types and concentrations of trace elements in tears and comparison to environmental data. The rural group included 12/28 men, mean age 45.2 ± 14.8 years. The urban group consisted of 11/14 men of mean age 27 ± 5.9 years. Six rural and all urban were active smokers. Air pollution data showed more toxic elements in the rural environment. On PIXE analysis, chlorine, sodium, and potassium were found in similar concentrations in all samples. Normalizing to chlorine yielded higher values of aluminum, iron, copper, and titanium in the rural group; aluminum was found only in the rural group. The higher levels of certain trace elements in the rural group may, in part, be a consequence of exposure to specific environmental conditions. No direct association was found with air pollution data. PIXE is useful to analyze trace elements in tears, which might serve as a marker for individual exposure to environmental pollutants in biomonitoring studies.

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Oct 2022 • arXiv preprint arXiv:2010.12220

Light chaotic dynamics in the transformation from curved to flat surfaces

Chenni Xu, Itzhack Dana, Li-Gang Wang, Patrick Sebbah

Light propagation on a two-dimensional curved surface embedded in a three-dimensional space has attracted increasing attention as an analog model of four-dimensional curved spacetime in laboratory. Despite recent developments in modern cosmology on the dynamics and evolution of the universe, investigation of nonlinear dynamics of light in non-Euclidean geometry is still scarce and remains challenging. Here, we study classical and wave chaotic dynamics on a family of surfaces of revolution by considering its equivalent conformally transformed flat billiard, with nonuniform distribution of refractive index. This equivalence is established by showing how these two systems have the same equations and the same dynamics. By exploring the Poincar\'{e} surface of section, the Lyapunov exponent and the statistics of eigenmodes and eigenfrequency spectrum in the transformed inhomogeneous table billiard, we find that the degree of chaos is fully controlled by a single geometric parameter of the curved surface. A simple interpretation of our findings in transformed billiards, the "fictitious force", allows to extend our prediction to other class of curved surfaces. This powerful analogy between two a prior unrelated systems not only brings forward a novel approach to control the degree of chaos, but also provides potentialities for further studies and applications in various fields, such as billiards design, optical fibers, or laser microcavities.

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Oct 2022 • Nature Physics

Topology-driven surface patterning of liquid spheres

Subhomoy Das, Alexander V Butenko, Yitzhak Mastai, Moshe Deutsch, Eli Sloutskin

Surfaces of classical spherical liquid droplets are isotropic, promoting the random distribution of surface-adsorbed molecules. Here we demonstrate a counterintuitive temperature-controlled self-assembly of well-defined and highly ordered patterns of surface-adsorbed fluorescent molecules on the surfaces of water-suspended spherical oil droplets. These patterns are induced by precisely self-positioned, topology-dictated structural defects in a crystalline monolayer covering these droplets’ surfaces over a wide temperature range. We elucidate the pattern formation mechanism, visualize the defects’ positions and map the stress fields within the surface crystal. The observed phenomena provide insights into the interfacial freezing effect on curved surfaces, enable precise positioning of functional ligands on droplets for their self-assembly into higher-hierarchy structures– and may also play an important role in vital …

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Oct 2022 • Journal of Electroanalytical Chemistry

Ultra-low palladium engineered nickel sulfide heterostructure supported on 3D nickel foam as a highly efficient and stable electrocatalyst for water oxidation

Hari Krishna Sadhanala, Akanksha Gupta, Aharon Gedanken

Electrochemical water splitting (EWS) has been a crucial process in the production of green fuels (oxygen and hydrogen) for a sustainable energy economy. One of the key processes in the EWS is water oxidation or the oxygen evolution reaction (OER). It is highly desirable to create cost-effective, efficient, and robust electrocatalysts for OER. Here, we present ultra-low Pd doped NiS-NiS2 heterostructure on NF (0.1PdNiS/NF) grown in-situ by acid etching followed by a simple hydrothermal sulfurization method for excellent OER electrocatalytic activity in alkaline media. Interestingly, low overpotential of 275 mV is required for the 0.1PdNiS/NF to achieve a current density of 10 mAcm-2, which is less than both NiS/NF (385 mV) and commercial RuO2/NF (370 mV). Because of the strong electronic interaction between Pd and NiS, 0.1PdNiS/NF has a small Tafel slope of 65 mV/dec and has shown excellent durability for …

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Oct 2022 • Advanced Science

Highly Stable 4.6 V LiCoO2 Cathodes for Rechargeable Li Batteries by Rubidium‐Based Surface Modifications

Tianju Fan, Yujie Wang, Villa Krishna Harika, Amey Nimkar, Kai Wang, Xiaolang Liu, Meng Wang, Leimin Xu, Yuval Elias, Munseok S Chae, Yonggang Min, Yuhao Lu, Netanel Shpigel, Doron Aurbach

Among extensively studied Li‐ion cathode materials, LiCoO2 (LCO) remains dominant for portable electronic applications. Although its theoretical capacity (274 mAh g−1) cannot be achieved in Li cells, high capacity (≤240 mAh g−1) can be obtained by raising the charging voltage up to 4.6 V. Unfortunately, charging Li‐LCO cells to high potentials induces surface and structural instabilities that result in rapid degradation of cells containing LCO cathodes. Yet, significant stabilization is achieved by surface coatings that promote formation of robust passivation films and prevent parasitic interactions between the electrolyte solutions and the cathodes particles. In the search for effective coatings, the authors propose RbAlF4 modified LCO particles. The coated LCO cathodes demonstrate enhanced capacity (>220 mAh g−1) and impressive retention of >80/77% after 500/300 cycles at 30/45 °C. A plausible mechanism …

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Sep 2022 • arXiv preprint arXiv:2209.03410

Exponential tails and asymmetry relations for the spread of biased random walks

Stanislav Burov, Wanli Wang, Eli Barkai

Exponential, and not Gaussian, decay of probability density functions was studied by Laplace in the context of his analysis of errors. Such Laplace propagators for the diffusive motion of single particles in disordered media were recently observed in numerous experimental systems. What will happen to this universality when an external driving force is applied? Using the ubiquitous continuous time random walk with bias, and the Crooks relation in conjunction with large deviations theory, we derive two properties of the positional probability density function that hold for a wide spectrum of random walk models: (I) Universal asymmetric exponential decay of for large , and (II) Existence of a time transformation that for large allows to express in terms of the propagator of the unbiased process (measured at a shorter time). These findings allow us to establish how the symmetric exponential-like tails, measured in many unbiased processes, will transform into asymmetric Laplace tails when an external force is applied.

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Sep 2022 • Journal of nanotheranostics

Antibody Delivery into the Brain by Radiosensitizer Nanoparticles for Targeted Glioblastoma Therapy

Omer Gal, Oshra Betzer, Liat Rousso-Noori, Tamar Sadan, Menachem Motiei, Maxim Nikitin, Dinorah Friedmann-Morvinski, Rachela Popovtzer, Aron Popovtzer

Background: Glioblastoma is the most lethal primary brain malignancy in adults. Standard of care treatment, consisting of temozolomide (TMZ) and adjuvant radiotherapy (RT), mostly does not prevent local recurrence. The inability of drugs to enter the brain, in particular antibody-based drugs and radiosensitizers, is a crucial limitation to effective glioblastoma therapy. Methods: Here, we developed a combined strategy using radiosensitizer gold nanoparticles coated with insulin to cross the blood–brain barrier and shuttle tumor-targeting antibodies (cetuximab) into the brain. Results: Following intravenous injection to an orthotopic glioblastoma mouse model, the nanoparticles specifically accumulated within the tumor. Combining targeted nanoparticle injection with TMZ and RT standard of care significantly inhibited tumor growth and extended survival, as compared to standard of care alone. Histological analysis of tumors showed that the combined treatment eradicated tumor cells, and decreased tumor vascularization, proliferation, and repair. Conclusions: Our findings demonstrate radiosensitizer nanoparticles that effectively deliver antibodies into the brain, target the tumor, and effectively improve standard of care treatment outcome in glioblastoma.

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Sep 2022 • Small

Bridging 1D Inorganic and Organic Synthesis to Fabricate Ultrathin Bismuth‐Based Nanotubes with Controllable Size as Anode Materials for Secondary Li Batteries

Kai Zong, Tianzhi Chu, Dongqing Liu, Andleeb Mehmood, Tianju Fan, Waseem Raza, Arshad Hussain, Yonggui Deng, Wei Liu, Ali Saad, Jie Zhao, Ying Li, Doron Aurbach, Xingke Cai

The growth of ultrathin 1D inorganic nanomaterials with controlled diameters remains challenging by current synthetic approaches. A polymer chain templated method is developed to synthesize ultrathin Bi2O2CO3 nanotubes. This formation of nanotubes is a consequence of registry between the electrostatic absorption of functional groups on polymer template and the growth habit of Bi2O2CO3. The bulk bismuth precursor is broken into nanoparticles and anchored onto the polymer chain periodically. These nanoparticles react with the functional groups and gradually evolve into Bi2O2CO3 nanotubes along the chain. 5.0 and 3.0 nm tubes with narrow diameter deviation are synthesized by using branched polyethyleneimine and polyvinylpyrrolidone as the templates, respectively. Such Bi2O2CO3 nanotubes show a decent lithium‐ion storage capacity of around 600 mA h g−1 at 0.1 A g−1 after 500 cycles, higher …

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Sep 2022 • Journal of Colloid and Interface Science

Salt-induced stability and modified interfacial energetics in self-faceting emulsion droplets

Pilkhaz M Nanikashvili, Alexander V Butenko, Moshe Deutsch, Daeyeon Lee, Eli Sloutskin


Sep 2022 • Langmuir

Counterions under a surface-adsorbed cationic surfactant monolayer: structure and thermodynamics

Eli Sloutskin, Lilach Tamam, Zvi Sapir, Benjamin M Ocko, Colin D Bain, Ivan Kuzmenko, Thomas Gog, Moshe Deutsch

The surface adsorption of ionic surfactants is fundamental for many widespread phenomena in life sciences and for a wide range of technological applications. However, direct atomic-resolution structural experimental studies of noncrystalline surface-adsorbed films are scarce. Thus, even the most central physical aspects of these films, such as their charge density, remain uncertain. Consequently, theoretical models based on contradicting assumptions as for the surface films’ ionization are widely used for the description and prediction of surface thermodynamics. We employ X-ray reflectivity to obtain the Ångström-scale surface-normal structure of surface-adsorbed films of the cationic surfactant cetyltrimethylammonium bromide (CTAB) in aqueous solutions at several different temperatures and concentrations. In conjunction with published neutron reflectivity data, we determine the surface-normal charge …

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Sep 2022 • Journal of Biomedical Optics

Non-invasive blood glucose sensing by machine learning of optic fiber-based speckle pattern variation

Deep Pal, Sergey Agadarov, Yevgeny Beiderman, Yafim Beiderman, Amitesh Kumar, Zeev Zalevsky

Significance: The ability to perform frequent non-invasive monitoring of glucose in the bloodstream is very applicable for diabetic patients.Aim: We experimentally verified a non-invasive multimode fiber-based technique for sensing glucose concentration in the bloodstream by extracting and analyzing the collected speckle patterns.Approach: The proposed sensor consists of a laser source, digital camera, computer, multimode fiber, and alternating current (AC) generated magnetic field source. The experiments were performed using a covered (with cladding and jacket) and uncovered (without cladding and jacket) multimode fiber touching the skin under a magnetic field and without it. The subject’s finger was placed on a fiber to detect the glucose concentration. The method tracks variations in the speckle patterns due to light interaction with the bloodstream affected by blood glucose.Results: The uncovered fiber …

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Sep 2022 • ACS Catalysis

Mixed-metal nickel–iron oxide aerogels for oxygen evolution reaction

Wenjamin Moschkowitsch, Noam Zion, Hilah C Honig, Naomi Levy, David A Cullen, Lior Elbaz

Alkaline electrolyte membrane electrolyzers are a promising technology to efficiently produce clean hydrogen without the use of critical raw materials. At the heart of these electrolyzers are the electrocatalysts, which facilitate the cathodic and anodic reactions, with the latter oxygen evolution reaction (OER) being the most sluggish. In recent years, aerogels have become a very well-studied class of materials due to their unique properties, including very high surface area. Until now, aerogels have not been used to catalyze the OER by themselves but were mainly considered catalyst supports. Here, mixed-metal nickel–iron oxide aerogels were synthesized with a modified epoxide route synthesis and tested as OER catalysts. Depending on the Ni/Fe ratio, they show very high catalytic activity and low overpotential to reach 10 mA cm–2 (at η = 380 mV). This activity is beyond that of the existing state-of-the-art platinum …

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Sep 2022 • Sensors and Actuators B: Chemical

Nitrogen-doped carbon dots as a highly selective and sensitive fluorescent probe for sensing Mg2+ ions in aqueous solution, and their application in the detection and imaging …

Hari Krishna Sadhanala, Saurav Aryal, Kusha Sharma, Ziv Orpaz, Shulamit Michaeli, Aharon Gedanken

The magnesium (Mg2+) ion is the second most abundant intracellular cation after potassium, and it is involved in a variety of biological processes and physiological functions. Because of the different effects which are dependent on Mg2+ ion concentration, it is critical to monitor Mg2+ ion levels in biological systems. Here, we report the hydrothermal synthesis of photoluminescent N-doped carbon dots (NCDs) using 4-Hydroxybenzaldehyde and 1, 2, 4, 5-benzenetetramine tetrahydrochloride as carbon and nitrogen sources, respectively. The as-synthesized NCDs demonstrated excitation dependent photoluminescence (PL) with a quantum yield of 16.2%. Because of water dispersibility and chelating functional groups, NCDs were used for highly selective detection of Mg2+ ions using ratiometric PL enhancement with a detection limit of 60 μM. Following that, based on highly biocompatibility and sensing of Mg2+ ions …

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Sep 2022 • Colloids and Surfaces A: Physicochemical and Engineering Aspects

Design of silane-based UV-absorbing thin coatings on polyethylene films

Taly Iline-Vul, Naftali Kanovsky, Daniel Yom-Tov, Merav Nadav-Tsubery, Shlomo Margel

UV-absorbing surfaces have received much attention and focus due to their relevance in a variety of research applications and industrial fields. However, these surfaces currently suffer from drawbacks such as instability due to leakage of the entrapped UV-absorbing compounds, complicated non-green synthetic processes, and/or lack of good optical properties. We propose a modified Stöber method where UV absorbing silane monomers containing the group2-hydroxy-4-(3-triethoxysilylpropoxy) diphenylketone (SiUV) in presence of the mesoporous producing surfactant cetyltrimethyl ammonium chloride (CTAC) was polymerized in an ethanol/water continuous phase under basic conditions. UV absorbing thin coatings onto polyethylene (PE) films were then spread with the former dispersion on corona-treated PE, followed by a thermal drying process. These films were highly UV absorbent and durable with …

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Sep 2022 • Elsevier Reference Collection in Chemistry

Quantum Tunneling in Computational Catalysis and Kinetics: Is it Really Important?

Ashim Nandi, Germán Molpeceres, Prashant K Gupta, Dan T Major, Johannes Kästner, Jan ML Marti, Sebastian Kozuch

Quantum tunneling (QT) is not an effect often considered in chemistry, and rightfully so. However, in many cases it is significant, and in some cases it is even considerable. In this chapter we will describe the basic tenets of QT with a focus on catalysis, followed by some of the most important tools to study and compute them. The chapter goes on to address the title of the chapter by discussing several clear cases of QT for hydrogen-based reactions in organometallic, enzymatic, astrochemical, and organic systems. The insights highlighted in the chapter showcase the importance of QT in specific catalyzed reactions and help uncover the instances that are worth of attention.

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Sep 2022 • Beilstein Archives

Synthetic study toward the diterpenoid aberrarone

Liang Shi, Zhiyu Gao, Yiqing Li, Yuanhao Dai, Yu Liu, Lili Shi, Hong-Dong Hao, Jiayue Fu, Bingbing Li, Zefang Zhou, Maosheng Cheng, Lu Yang, Yongxiang Liu, Anaïs Rousseau, Guillaume Vincent, Cyrille Kouklovsky, Shani Zev, Marion Ringel, Ronja Driller, Bernhard Loll, Thomas Brück, Dan T Major, Elenilson Figueiredo da Silva, Krist Helen Antunes Fernandes, Denise Diedrich, Jessica Gotardi, Marcia Silvana Freire Franco, Ana Paula Duarte de Souza, Simone Cristina Baggio Gnoatto, Jannis A Reich, Miriam Aßmann, Kristin Hölting, Paul Bubenheim, Jürgen Kuballa, Andreas Liese, Dong Hyun Kim, Zahra Khan, Sun Yeou Kim, Sang Un Choi, Chung Sub Kim, Kang Ro Lee, Meifang Wu, Xiangdong Su, Yichuang Wu, Yuanjing Luo, Ying Guo, Yongbo Xue, Phil Servatius, Uli Kazmaier, Shun Saito, Kanji Indo, Naoya Oku, Hisayuki Komaki, Masashi Kawasaki, Yasuhiro Igarashi, Haipin Zhou, Zihan Rui, Yiming Yang, Shengtao Xu, Yutian Shao, Long Liu, Hafsa Tayyab, Nor FW Ridzwan, Saharuddin B Mohamad, Takashi Nishiyama, Erina Hamada, Daishi Ishii, Yuuto Kihara, Nanase Choshi, Natsumi Nakanishi, Mari Murakami, Kimiko Taninaka, Noriyuki Hatae, Tominari Choshi, Andrés F Bonilla, Diego A Bonilla, Sandip Radhakisan Ugale, Somnath S Gholap, Roberta Di Lecce, Marco Masi, Benedetto Teodoro Linaldeddu, Gennaro Pescitelli, Lucia Maddau, Antonio Evidente, Florian Mann, Daiane Szczerbowski, Lisa de Silva, Melanie McClure, Marianne Elias, Stefan Schulz, Virendra Kumar, Abdus Salam, Dileep Kumar, Tabrez Khan, Zhishu Zeng, Jun Xie, Guangyan Luo, Zhu Tao, Qianjun Zhang, Xu-Dong Zhou

Unless otherwise stated, all reactions were performed with magnetic stirring under a positive pressure of nitrogen or argon gas. Over-dried glassware (over temperature of 150 ºC) was further dried with a heat-gun at 650 ºC under vacuum, followed by back-filling with inert gas, three times and fitted with rubber septa prior to use. Solids were added under inert gas counter flow or were dissolved and transferred in the appropriate solvent. Solutions and liquids reagents were transferred to reaction vessels by oven-dried stainless-steel cannulas or nitrogen flushed syringes. Low temperature reactions were carried out in a Dewar vessel filled with acetone/dry ice (-78 ºC) or distilled water/ice (0 ºC). High temperature reactions were conducted using a heated silicon oil bath in reaction vessels equipped with a reflux condenser.

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Sep 2022 • ACS Catalysis

Mixed-Metal Nickel–Iron Oxide Aerogels for Oxygen Evolution Reaction

Wenjamin Moschkowitsch, Noam Zion, Hilah C Honig, Naomi Levy, David A Cullen, Lior Elbaz

Alkaline electrolyte membrane electrolyzers are a promising technology to efficiently produce clean hydrogen without the use of critical raw materials. At the heart of these electrolyzers are the electrocatalysts, which facilitate the cathodic and anodic reactions, with the latter oxygen evolution reaction (OER) being the most sluggish. In recent years, aerogels have become a very well-studied class of materials due to their unique properties, including very high surface area. Until now, aerogels have not been used to catalyze the OER by themselves but were mainly considered catalyst supports. Here, mixed-metal nickel–iron oxide aerogels were synthesized with a modified epoxide route synthesis and tested as OER catalysts. Depending on the Ni/Fe ratio, they show very high catalytic activity and low overpotential to reach 10 mA cm–2 (at η = 380 mV). This activity is beyond that of the existing state-of-the-art platinum …

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Sep 2022 • arXiv preprint arXiv:2209.00480

Coherence and realism in the Aharonov-Bohm effect

Ismael L Paiva, Pedro R Dieguez, Renato M Angelo, Eliahu Cohen

The Aharonov-Bohm effect is a fundamental topological phenomenon with a wide range of applications. It consists of a charge encircling a region with a magnetic flux in a superposition of wavepackets having their relative phase affected by the flux. In this work, we analyze this effect using an entropic measure known as realism, originally introduced as a quantifier of a system's degree of reality and mathematically related to notions of global and local quantum coherence. More precisely, we look for observables that lead to gauge-invariant realism associated with the charge before it completes its loop. We find that the realism of these operators has a sudden change when the line connecting the center of both wavepackets crosses the solenoid. Moreover, we consider the case of a quantized magnetic field source, pointing out similarities and differences between the two cases. Finally, we discuss the implications of these results to the understanding of the effect.

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