BINA

Ultrasonic irradiation of molten metals in liquid media causes dispersion of the metals into suspensions of micro- and nanoparticles that can be separated. This is applicable mainly to low-mp elemental metals or alloys, but higher mp elemental metals or alloys were also reported. Among metals, mercury and gallium exhibit especially-low melting points and are thus considered as liquid metals (LMs). Sonication of mercury in aqueous solutions of certain metal ions can cause simultaneous reduction of the ions and reactions between the metals. Gallium can be melted and sonicated in warm water, as well as in aqueous solutions of various solutes such as metal ions and organic compounds, which opened a wide window of interactions between the gallium particles and the solutes. Sonication of molten metals in organic liquids, such as polyethylene glycol (PEG) 400, forms carbon dots (C-dots) doped with …

Nanoscale Page 1 Nanoscale rsc.li/nanoscale The Royal Society of Chemistry is the world's leading chemistry community. Through our high impact journals and publications we connect the world with the chemical sciences and invest the profits back into the chemistry community. IN THIS ISSUE ISSN 2040-3372 CODEN NANOHL 15(17) 7595–8030 (2023) Cover See Munho Kim, Guo-En Chang et al., pp. 7745–7754. Image reproduced by permission of Guo-En Chang from Nanoscale, 2023, 15, 7745. Inside cover See Palyam Subramanyam, Vasudevanpillai Biju et al., pp. 7695–7702. Image reproduced by permission of Vasudevanpillai Biju from Nanoscale, 2023, 15, 7695. REVIEWS 7608 Integration of functional peptides into nucleic acid-based nanostructures Jessica S. Freitag, Christin Möser, Robel Belay, Basma Altattan, Nico Grasse, Bhanu Kiran Pothineni, Jörg Schnauß and David M. Smith* 7625 …

EPR in-cell spin-labeling was applied to CueR in E. coli. The methodology employed a Cu(II)-NTA complexed with dHis. High resolved in-cell distance distributions were obtained revealing minor differences between in-vitro and in-cell data. This methodology allows to study structural changes of any protein in-cell, independent of size or cellular system

The realization of lithium-oxygen (Li-O2) batteries has been impeded by parasitic reactions that cause cell component degradation, often accompanied by the release of CO2 gas during oxidation reactions. The use of halide-based redox mediators (RMs) like LiBr and LiI has been proposed as a strategy to reduce overpotentials during oxygen evolution reactions and thus suppress the subsequent evolution of CO2. However, there is a scarcity of research examining the effectiveness of these RMs in the direct mitigation of parasitic reactions. In this study, we investigated the evolution of CO2 during the oxidation processes using an online electrochemical mass spectrometer. The results show that cells without RMs exhibited high overpotentials and significant CO2 evolution from the first charging cycle. In contrast, the addition of 50mM LiI to the electrolyte resulted in a delay in CO2 evolution, observed only after several …

Confocal microscopes have been the workhorses of 3-D biological imaging, but they are slow, offer limited depth penetration and collect only ballistic photons. With their inefficient use of excitation photons they expose biological samples to an often intolerably high light burden. The speed limitation and photo-bleaching risk can be somewhat relaxed in a spinning-disk geometry, due to shorter pixel dwell times and rapid re-scans during image capture. Alternatively, light-sheet microscopes rapidly image large volumes of transparent or chemically cleared samples. Finally, with infrared excitation and efficient scattered-light collection, 2-photon microscopy allows deep-tissue imaging, but it remains slow. Here, we describe a new optical scheme that borrows the best from three different worlds: the speed and direct-view from a spinning-disk confocal, deep tissue-penetration and intrinsic optical sectioning from 2-photon …

Chaos, namely exponential sensitivity to initial conditions, is generally considered a nuisance, inasmuch as it prevents long‐term predictions in physical systems. Here, an easily accessible approach to undo deterministic chaos and tailor ray trajectories in arbitrary 2D optical billiards by introducing spatially varying refractive index therein is presented. A new refractive index landscape is obtained by a conformal mapping, which makes the trajectories of the chaotic billiard fully predictable and the billiard fully integrable. Moreover, trajectory rectification can be pushed a step further by relating chaotic billiards with non‐Euclidean geometries. Two examples are illustrated by projecting billiards built on a sphere as well as the deformed spacetime outside a Schwarzschild black hole, which respectively lead to all periodic orbits and spiraling trajectories remaining away from the boundaries of the transformed 2D billiards …

Total internal reflection fluorescence (TIRF) has come of age, but a reliable and easy-to-use tool for calibrating evanescent-wave penetration depths is missing. We provide a test-sample for TIRF and other axial super-resolution microscopies for emitter axial calibration. Our originality is that nanometer(nm) distances along the microscope’s optical axis are color-encoded in the form of a multi-layered multi-colored transparent sandwich. Emitter layers are excited by the same laser but they emit in different colors. Layers are deposited in a controlled manner onto a glass substrate and protected with a non-fluorescent polymer. Decoding the penetration depth of the exciting evanescent field, by spectrally unmixing of multi-colored samples is presented as well. Our slide can serve as a test sample for quantifying TIRF, but also as an axial ruler for nm-axial distance measurements in single-molecule localization …

The characterization of ultrathin transparent films is paramount for various optoelectronic materials, coatings, and photonics. However, characterizing such thin layers is difficult and it requires specialized clean‐room equipment and trained personnel. Here, a contact‐less, all‐optical method is introduced and validated for characterizing nanometric transparent films using far‐field optics. A series of nanometric, smooth, and homogeneous layered samples are fabricated first, alternating transparent spacer and fluorescent layers in a controlled manner. Fluorescence radiation pattern originating from the thin fluorophore layers is then recorded and analyzed and quantitative image analysis is used to perform in operando measurements of the refractive index, film homogeneity and to estimate axial fluorophore distances at a sub‐wavelength scale with a precision of a few of nanometers. The results compare favorably to …

Metamaterials and plasmonic structures made from aluminum (Al) have attracted significant interest due to their low cost, long-term stability, and the relative abundance of aluminum compared to the rare metals. Also, aluminum displays distinct dielectric properties allowing for the excitation of surface plasmons in the ultraviolet region with minimal non-radiative losses. Despite these clear advantages, most of the research has been focused on either gold or silver, probably due to difficulties in forming smooth thin films of aluminum. In the present work, we detect and characterize second harmonic generation (SHG) in the optical regime, emanating from triangular hole arrays milled into thin aluminum films in reflection mode, at normal incidence. We report intense nonlinear responses, year-long stability, and overall superior performances with respect to gold and silver. The robustness of the Al structures and high …

Second harmonic generation (SHG) is forbidden for centrosymmetric materials such metals. Yet, symmetry can be broken by introducing plasmonic nano-structures which lead to enhancement of the electromagnetic field at both the fundamental and the SH frequencies. Using non-linear microscopy, we experimentally demonstrate enhanced SHG from isosceles triangular cavities (~215 nm side length, 200 nm base) milled in thin aluminum film. Upon strong interaction between the cavities, they behave as a single unit and response in a coherent manner, i.e. SHG is observed from the coupled system. The hybridization between the cavities is not only dependent on the distance between them, but their spatial arrangement is found to be a crucial parameter. That is, the SHG efficiency can be enhanced upon different arrangement of the same cavities, holding the same distance between them. We characterize those …

Platinum group metal‐free catalysts have been considered the most promising alternative for platinum‐based catalysts for the oxygen reduction reaction in fuel cells. Despite the significant advancement made in activity, their viability as fuel cell catalysts is still questionable due to their low durability. So far, deciphering the degradation mechanisms of this class of catalysts has been hampered by their undefined structure. Herein, we used a molecular model catalyst, iron‐phthalocyanine, featuring Fe−N4 active sites with resemblance to those in the more active Fe−N−C catalysts, and studied their degradation mechanisms. Based on X‐ray photoelectron spectroscopy and the electrochemical measurements, three main demetallation processes were identified: at potentials higher than 0.65 V vs. RHE, where the metal center is Fe3+, an electrochemical oxidation of the ligand ring is occurring, between 0.6 and 0.2 V …

{Velocity map imaging (VMI) is a powerful technique that allows to infer the kinetic energy of ions or electrons that are produced from a large volume in space with good resolution. The size of the acceptance volume is determined by the spherical aberrations of the ion optical system. Here we present an analytical derivation for velocity map imaging with no spherical aberrations. We will discuss a particular example for the implementation of the technique that allows using the reaction microscope recently installed in the Cryogenic storage ring (CSR) in a VMI mode. SIMION simulations confirm that a beam of electrons produced almost over the entire volume of the source region, with width of 8 cm, can be focused to a spot of 0.1 mm on the detector. The use of the same formalism for position imaging, as well as an option of position imaging in one axis and velocity map imaging in a different axis, are also discussed.

Dynamics and Fluctuations in Biomedical Photonics XX Page 1 PROGRESS IN BIOMEDICAL OPTICS AND IMAGING Vol. 24 No. 27 Volume 12378 Proceedings of SPIE, 1605-7422, V. 12378 SPIE is an international society advancing an interdisciplinary approach to the science and application of light. Dynamics and Fluctuations in Biomedical Photonics XX Valery V. Tuchin Martin J. Leahy Ruikang K. Wang Zeev Zalevsky Editors 29–30 January 2023 San Francisco, California, United States Sponsored and Published by SPIE Dynamics and Fluctuations in Biomedical Photonics XX, edited by Valery V. Tuchin, Martin J. Leahy, Ruikang K. Wang, Zeev Zalevsky, Proc. of SPIE Vol. 12378, 1237801 · © 2023 SPIE · 1605-7422 · doi: 10.1117/12.2676834 Proc. of SPIE Vol. 12378 1237801-1 Page 2 The papers in this volume were part of the technical conference cited on the cover and title page. Papers were selected and …

Emerging energy storage systems based on abundant and cost-effective materials are key to overcome the global energy and climate crisis of the 21st century. Rechargeable Magnesium Batteries (RMB), based on Earth-abundant magnesium, can provide a cheap and environmentally responsible alternative to the benchmark Li-ion technology, especially for large energy storage applications. Currently, RMB technology is the subject of intense research efforts at laboratory scale. However, these emerging approaches must be placed in a real-world perspective to ensure that they satisfy key technological requirements. In an attempt to bridge the gap between laboratory advancements and industrial development demands, herein, we report the first non-aqueous multilayer RMB pouch cell prototypes and propose a roadmap for a new advanced RMB chemistry. Through this work, we aim to show the great unrealized …

Background Myocardial infarction (MI) and heart failure (HF) are associated with an increased incidence of cancer. The mechanism is complex and unclear. Here, we aimed to test our hypothesis that cardiac small extracellular vesicles (sEVs), particularly cardiac mesenchymal stromal cells-derived sEVs (cMSC-sEVs), contribute to the link between post-MI HF and cancer. Methods We purified and characterized sEVs from the whole heart and cultured cMSCs. Then, we analyzed cMSC-EV cargo and pro-neoplastic effects on several types of cancer cell lines, macrophages, and endothelial cells. Next, we modeled post-MI HF along with heterotopic and orthotopic lung and breast cancer tumors in mice. We used cMSC-sEV transfer to assess sEV biodistribution and its effect on tumor growth. Finally, we tested the effects of sEV depletion and spironolactone treatment on cMSC-EV release and tumor growth. Results Post-MI hearts, particularly cMSCs, produced more sEVs with pro-neoplastic cargo than non-failing hearts did. Proteomic analysis revealed unique protein profiles and higher quantities of tumor-promoting cytokines, proteins, and microRNAs in cMSC-sEVs from failing hearts. The pro-neoplastic effects of cMSC-sEVs varied with different types of cancer cells, substantially affecting lung cancer cells relative to other more aggressive cancer cell lines. We also found that post-MI cMSC-sEVs activated resting macrophages into pro-angiogenic and pro-tumorigenic states in vitro. At 28-day follow-up analysis, mice with post-MI HF developed larger lung tumors than did sham-MI mice. Adoptive transfer of cMSC-sEVs from failing hearts accelerated …

Recovery from damage in materials helps extend their useful lifetime and of devices that contain them. Given that the photodamages in HaP materials and based devices are shown to recover, the question arises if this also applies to mechanical damages, especially those that can occur at the nanometer scale, relevant also in view of efforts to develop flexible HaP‐based devices. Here, this question is addressed by poking HaP single crystal surfaces with an atomic force microscope (AFM) tip under both ultra‐high vacuum (UHV) and variably controlled ambient water vapor pressure conditions. Sequential in situ AFM scanning allowed real‐time imaging of the morphological changes at the damaged sites. Using methylammonium (MA) and cesium (Cs) variants for A‐site cations in lead bromide perovskites, the experiments show that nanomechanical damages on methylammonium lead bromide (MAPbBr3) crystals …

New naphthocorrole ligands, display both the cavity size of corroles and the dianionic character of porphyrins. Nonaromatic and yet flaunting deceptively porphyrin-like optical spectra, they are readily accessible via a simple protocol.

The development of bioinspired catalysts for oxygen reduction reaction is one of the most prominent pathways in the search for active materials to replace Pt-based catalysts in fuel cells. Herein, we report innovative bioinspired catalysts using a directed synthetic pathway to create adjacent Cu and Fe sites. This catalyst is composed of a covalent 3D framework in an aerogel form. Aerogels are high surface area and porous hierarchical structures that can allow the formation of ultrahigh active site density and optimized mass transport of reactants and products to and from the catalytic sites. The aerogel-based catalyst exhibits high performance in a half-cell in 0.1 M KOH, with an onset potential of 0.94 V vs RHE and half-wave potential of E1/2 = 0.80 V vs RHE, high selectivity toward the four-electron reduction of oxygen to hydroxide anions, and high durability. These results are well-translated to the anion exchange …

Nanoporous metallic systems exhibit a new generation of advanced materials with potential in a wide variety of technological fields among them catalysis, photonics, optoelectronics and sensors.Their high surface-to-volume ratio, multimodal nanoscale moieties, ability to host guest materials, and inhomogeneous surface at the submicron scale distinct them from both bulk metals and conventional plasmonic materials as well as meta-surfaces. Those structures can be prepared through different fabrication and synthesis strategies including chemical dealloying, assembly of pre-synthesized metallic nanoparticles, and via templating. In a sharp contrast with these preparation strategies, we have demonstrated one can fabricate a macroscopic nanopourus metallic networks by using physical vapor deposition in a short single-step process. These materials are highly pure, and they show very unique linear and non-linear …

Climate change calls for a change in the way we use and produce energy, and carbon-free has become the future direction of energy production and utilization. To obtain this, we must rely on sustainable energy sources such as wind and sun, but their intermittence limits the production of clean energy to only a few hours a day. To overcome this issue, energy storage and production technologies must be developed. Although several technologies have been proposed, the only viable scheme that could allow short-to-long-term storage and efficient energy transportation at-scale is the hydrogen economy, which relies on three pillars of technology: electrolyzers, hydrogen storage and fuel cells. In recent years, there have been rapid technological advances in hydrogen production, new hydrogen storage materials, and high-performance hydrogen fuel cells, etc. However, there are still numerous technological difficulties …

The development of vacuum‐deposited perovskite materials and devices is partially slowed down by the minor research effort in this direction, due to the high cost of the required research tools. But there is also another factor, thermal co‐deposition in high vacuum involves the simultaneous sublimation of several precursors with an overall deposition rate in the range of few Å s−1. This leads to a deposition time of hours with only a single set of process parameters per batch, hence to a long timeframe to optimize even a single perovskite composition. Here we report the combinatorial vacuum deposition of wide bandgap perovskites using 4 sources and a non‐rotating sample holder. By using small pixel substrates, more than 100 solar cells can be produced with different perovskite absorbers in a single deposition run. The materials are characterized by spatially resolved methods, including optical, morphological …