BINA

The monitoring of ionizing radiation is critical for the safe operation of nuclear and other high-power plants. Fiber-optic sensing of radiation has been pursued for over 45 years. Most protocols rely on radiation effects on the optical properties of the fiber. Here we propose a new concept, in which the opto-mechanics of standard fibers coated by thin layers of fluoroacrylate polymer are observed instead. The time-of-flight of radial acoustic waves through the coating is evaluated by forward stimulated Brillouin scattering measurements. The time-of-flight is seen to decrease monotonically with the overall dosage of gamma radiation from a cobalt source. Variations reach 15% of the initial value for 180 Mrad dose and remain stable for at least several weeks following exposure. The faster times-of-flight are consistent with a radiation-induced increase in the coating stiffness, observed in offline analysis. The effects on the …

Torsional-radial guided acoustic modes in standard single-mode fibers are stimulated by pump tones of linear and orthogonal polarizations. The same acoustic modes induce photo-elastic birefringence. Circularly polarized pump waves can generate acoustic vortex beams.

Logical entropy gives a measure, in the sense of measure theory, of the distinctions of a given partition of a set, an idea that can be naturally generalized to classical probability distributions. Here, we analyze how fundamental concepts of this entropy and other related definitions can be applied to the study of quantum systems, leading to the introduction of the quantum logical entropy. Moreover, we prove several properties of this entropy for generic density matrices that may be relevant to various areas of quantum mechanics and quantum information. Furthermore, we extend the notion of quantum logical entropy to post-selected systems.

Inorganic nanotubes (INTs) and fullerene-like nanoparticles (NPs) of WS 2/MoS 2 penetrate and exfoliate at the contact interface and facilitate tribofilm formation. While the tribological properties are greatly improved by exfoliated NPs that shed easily, they may be diminished by agglomeration in oil. Therefore, surface functionalization is employed to improve dispersion in oil-based suspensions. Here, WS 2 INTs were functionalized by polytetrafluoroethylene (PTFE) in a simple and cost-effective bath sonication method. WS 2-INTs with two concentrations of added PTFE were characterized by scanning and transmission electron microscopy, micro-Raman spectroscopy, and thermogravimetric analysis. Superior distribution of WS 2 was observed before and during friction experiments. Chemical analysis showed a significantly greater amount of PTFE-coated INTs on rubbed surfaces, in accordance with the improved friction and wear properties. View Full-Text

We describe an experimental setup designed for transport measurement of thin disordered superconducting films as a function of pressure up to several GPa. We use a specially designed single screw diamond anvil cell that allows the gradual increase of high pressure at cryogenic temperatures. By depositing amorphous films of disordered superconducting indium oxide directly on the diamond, we avoid the effect of pressure-induced structural changes in the substrate. Using this technique, we are able to drive thin films through a pressure tuned superconductor–insulator transition.

The origin of the low densities of electrically active defects in Pb halide perovskite (HaP), a crucial factor for their use in photovoltaics, light emission, and radiation detection, remains a matter of discussion, in part because of the difficulty in determining these densities. Here, we present a powerful approach to assess the defect densities, based on electric field mapping in working HaP-based solar cells. The minority carrier diffusion lengths were deduced from the electric field profile, measured by electron beam-induced current (EBIC). The EBIC method was used earlier to get the first direct evidence for the n-i-p junction structure, at the heart of efficient HaP-based PV cells, and later by us and others for further HaP studies. This manuscript includes EBIC results on illuminated cell cross sections (in operando) at several light intensities to compare optoelectronic characteristics of different cells made by different groups …

Copper is essential for proper functioning of cells but is dangerous in unregulated concentrations. One of the members in the bacterial system responsible for facilitating copper homeostasis is the copper efflux regulator (CueR) protein. Upon copper binding, CueR induces transcription of additional copper homeostasis proteins via a cascade of events. There are some available crystal structures of CueR, in the holo (copper-bound), active (copper- and DNA-bound), and repressed (only DNA-bound) states, and these structures suggest that transcription initiation involves a distortion in the promoter DNA strand. In this work, we study the dynamic behavior of the protein, using molecular dynamics simulations, and compare with available electron paramagnetic resonance measurements for validation. We develop simple force-field parameters to describe the copper-binding motif, thus enabling the use of simplified …

The functionality of a nanoscale silicon-based optoelectronic modulator is deeply analyzed while it appears that two competing processes, thermal and photonic, are occurring at the same time, and are preventing the optimization of the electro-optics coupling. While an incident illumination-beam first process is translated into photons, generating pairs of electrons-holes, a second process of thermal generation, creating phonons enables a loss of energy. Complementary studies, combining strong analytical models and numerical simulations, enabled to better understand this competition between photonic and thermal activities, in order to optimize the modulator. Moreover, in order to prevent unnecessary heating effects and to present a proposed solution, a picosecond pulsed laser is suggested and demonstrated as the ultimate solution so no energy will be wasted in heat, and still the photonic energy will be fully used. First everanalytical solution to the heating produced due to the laser illumination applied on a nano-photonic device, while the illumination is produced in a periodic time changing function, eg a pulsed illumination, is presented. The present case study and proposed adapted solution can serve as a basis of generic approach in sensors’ activation towards optimized photonics absorption.

In recent decades rechargeable Mg batteries (RMB) technologies have attracted much attention because the use of thin Mg foils anodes may enable to develop high energy density batteries. One of the most critical challenges for devolving RMB is finding suitable electrolyte solutions that enable efficient and reversible Mg cells operation. Most RMB studies concentrate on the development of novel electrolyte systems, while only few studies have focused on the practical feasibility of using pure metallic Mg as the anode material. Pure Mg metal anodes have been demonstrated to be useful in studying the fundamentals of nonaqueous Mg electrochemistry. However, pure Mg metal may not be suitable for mass production of ultrathin foils (< 100 microns) due to its limited ductility. The metals industry overcomes this problem by using ductile Mg alloys. We demonstrate herein the feasibility of processing ultrathin Mg …

Rechargeable magnesium batteries (RMBs) are highly attractive due to their high volumetric capacity, relatively low cost, and enhanced safety. Significant progress in the development of RMBs was the introduction of nonaqueous electrolyte solutions that enable reversible electrodeposition of Mg metal. These solutions contain a unique mixture of organo− aluminum and chloro− aluminum species. While these solutions are shown to be stable during cathodic polarization, the presence of chlorine anions in the solution can promote the corrosion process during the anodic polarization. Among all the cell components, the cathode current collector is most prone to corrosive processes. In this study, we characterize the corrosion behavior of different metallic current collectors in standard APC (All-Phenyl Complex) electrolyte solutions by following their electrochemical response and surface morphology changes during …

LiNi0.8Co0.1Mn0.1O2 (NCM811) is a promising cathode material for long range electric vehicles. However, the material suffers severe chemo-mechanical degradation that can cause gradual capacity loss upon prolonged cycling. Surface passivation of NMC811 was demonstrated to help in retaining the structural integrity of the material upon extended cycling. Herein, we report the surface passivation of the NCM811 using Li2S and Na2S precursors via direct and simple wet chemical treatment, for the mitigation of parasitic reactions at the electrode electrolyte interphase. This phenomenon is accompanied by increase in the oxidation state of sulfur (from sulfide to sulfate) and partial reduction in the oxidation state of nickel. Electrochemical performance measurements show that the M2SO4 (M: Li, Na) protection layer on NMC811 behaves as an artificial cathode electrolyte interphase (ACEI) that enhance the capacity …

Extracting the theoretically high capacity of LiCoO2 (LCO) is desirable for enhancing the energy density of currently used lithium‐ion batteries (LIBs) for portable devices. The bottleneck for exhibiting the high capacity is associated with the limited cut‐off positive voltages beyond which degradation of electrode/electrolyte takes place. In this work, we apply hybrid organic‐inorganic alucone thin film grown directly on LCO by a molecular layer deposition (MLD) method, using sequential exposure to Al‐based and organic‐based precursors. The alucone thin films enabled the high voltage operation of the LCO cathode (> 4.5 V), acting as a protection layer. Electrochemical studies proved that alucone coated LCO show enhanced electrochemical performances with improved cycling stability and enhanced specific capacity, relative to uncoated LCO. Amongst the studied films, 10 nm ethylene glycol/Al coated LCO have …

In sufficiently strong scattering media, light transport is suppressed and modes are exponentially localized. Anderson-like localized states have long been recognized as potential candidates for high-Q optical modes for low-threshold, cost-effective random lasers. Operating in this regime remains, however, a challenge since Anderson localization is difficult to achieve in optics, and nonlinear mode interaction compromises its observation. Here, we exhibit individually each lasing mode of a low-dimension solid-state random laser by applying a non-uniform optical gain. By undoing gain competition and cross-saturation, we demonstrate that all lasing modes are spatially localized. We find that selective excitation significantly reduces the lasing threshold, while lasing efficiency is greatly improved. We show further how their spatial locations are critical to boost laser power efficiency. By …

This work investigates, for the first time, the application of sonochemically prepared bovine serum albumin (BSA) microspheres (BSAMS) as adsorbents of industrial organic pollutant dyes, such as rhodamine B (RhB), rhodamine 6G (Rh6G), and methylene blue (MB). These dyes also serve as model compounds for other organic pollutants such as bisphenol A and 2-nitrophenol. Adsorption kinetics of the dyes by the BSAMS was studied using pseudo-first-order (PFO) and pseudo-second-order (PSO) kinetic models. It was found that RhB follows PFO, with an adsorption capacity, qe,cal, of 7.9 mg/g, which was closer to the experimental adsorption capacity of qe,exp. of 7.6 mg/g. However, MB and Rh6G were controlled by PSO kinetics, with a qe,cal of 5.6 mg/g for MB and 6.6 mg/g for Rh6G, closer to the experimental adsorption capacity of 5.7 and 6.4 mg/g, respectively. The intraparticle diffusion (ID) model applied to …

Inorganic nanotubes (INTs) and fullerene-like nanoparticles (NPs) of WS2/MoS2 penetrate and exfoliate at the contact interface and facilitate tribofilm formation. While the tribological properties are greatly improved by exfoliated NPs that shed easily, they may be diminished by agglomeration in oil. Therefore, surface functionalization is employed to improve dispersion in oil-based suspensions. Here, WS2 INTs were functionalized by polytetrafluoroethylene (PTFE) in a simple and cost-effective bath sonication method. WS2-INTs with two concentrations of added PTFE were characterized by scanning and transmission electron microscopy, micro-Raman spectroscopy, and thermogravimetric analysis. Superior distribution of WS2 was observed before and during friction experiments. Chemical analysis showed a significantly greater amount of PTFE-coated INTs on rubbed surfaces, in accordance with the improved friction and wear properties.

Protein immobilization on material surfaces is emerging as a powerful tool in the design of devices and active materials for biomedical and pharmaceutical applications as well as for catalysis. Preservation of the protein’s biological functionality is crucial to the design process and is dependent on the ability to maintain its structural and dynamical integrity while removed from the natural surroundings. The scientific techniques to validate the structure of immobilized proteins are scarce and usually provide limited information as a result of poor resolution. In this work, we benchmarked the ability of standard solid-state NMR techniques to resolve the effects of binding to dissimilar silica materials on a model protein. In particular, the interactions between ubiquitin and the surfaces of MCM41, SBA15, and silica formed in situ were tested for their influence on the structure and dynamics of the protein. It is shown that the …

Rechargeable magnesium batteries (RMBs) are highly attractive due to their high volumetric capacity, relatively low cost, and enhanced safety. Significant progress in the development of RMBs was the introduction of nonaqueous electrolyte solutions that enable reversible electrodeposition of Mg metal. These solutions contain a unique mixture of organo− aluminum and chloro− aluminum species. While these solutions are shown to be stable during cathodic polarization, the presence of chlorine anions in the solution can promote the corrosion process during the anodic polarization. Among all the cell components, the cathode current collector is most prone to corrosive processes. In this study, we characterize the corrosion behavior of different metallic current collectors in standard APC (All-Phenyl Complex) electrolyte solutions by following their electrochemical response and surface morphology changes during …

The origin of the low densities of electrically active defects in Pb halide perovskite (HaP), a crucial factor for their use in photovoltaics, light emission, and radiation detection, remains a matter of discussion, in part because of the difficulty in determining these densities. Here, we present a powerful approach to assess the defect densities, based on electric field mapping in working HaP-based solar cells. The minority carrier diffusion lengths were deduced from the electric field profile, measured by electron beam-induced current (EBIC). The EBIC method was used earlier to get the first direct evidence for the n-i-p junction structure, at the heart of efficient HaP-based PV cells, and later by us and others for further HaP studies. This manuscript includes EBIC results on illuminated cell cross sections (in operando) at several light intensities to compare optoelectronic characteristics of different cells made by different groups …

LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811) is a promising cathode material for long range electric vehicles. However, the material suffers severe chemo-mechanical degradation that can cause gradual capacity loss upon prolonged cycling. Surface passivation of NMC811 was demonstrated to help in retaining the structural integrity of the material upon extended cycling. Herein, we report the surface passivation of the NCM811 using Li 2 S and Na 2 S precursors via direct and simple wet chemical treatment, for the mitigation of parasitic reactions at the electrode electrolyte interphase. This phenomenon is accompanied by increase in the oxidation state of sulfur (from sulfide to sulfate) and partial reduction in the oxidation state of nickel. Electrochemical performance measurements show that the M 2 SO 4 (M: Li, Na) protection layer on NMC811 behaves as an artificial cathode electrolyte interphase (ACEI) that enhance the …

Sustainable antibacterial–antioxidant films were prepared using in situ graftings of silica nanoparticle (SNP) precursors with covalently attached bioactive agents benzoic acid (ba) or curcumin (cur) on polyvinyl alcohol (PVA). The modified PVA-SNP, PVA-SNP-ba and PVA-SNP-cur films were characterized using spectroscopic, physicochemical and microscopic methods. The prepared films showed excellent antibacterial and antioxidant activity, and increased hydrophobicity providing protection from undesired moisture. The PVA-SNP-ba films completely prevented the growth of the foodborne human pathogen Listeria innocua, whereas PVA-SNP-cur resulted in a 2.5 log reduction of this bacteria. The PVA-SNP-cur and PVA-SNP-ba films showed high antioxidant activity of 15.9 and 14.7 Mm/g TEAC, respectively. The described approach can serve as a generic platform for the formation of PVA-based packaging materials with tailor-made activity tuned by active substituents on silica precursors. Application of such biodegradable films bearing safe bioactive agents can be particularly valuable for advanced sustainable packaging materials in food and medicine.

Despite the continuous progress in the research and development of Ti3C2Tx (MXene) electrodes for high-power batteries and supercapacitor applications, the role of the anions in the electrochemical energy storage and their ability to intercalate between the MXene sheets upon application of positive voltage have not been clarified. A decade after the discovery of MXenes, the information about the possibility of anion insertion into the restacked MXene electrode is still being questioned. Since the positive potential stability range in diluted aqueous electrolytes is severely limited by anodic oxidation of the Ti, the possibility of anion insertion was evaluated in concentrated aqueous electrolyte solutions and aprotic electrolytes as well. To address this issue, we have conducted in situ gravimetric electrochemical quartz crystal microbalance with dissipation monitoring (EQCM-D) measurements in highly concentrated LiCl …