BINA

Recurrence time quantifies the duration required for a physical system to return to its initial state, playing a pivotal role in understanding the predictability of complex systems. In quantum systems with subspace measurements, recurrence times are governed by Anandan-Aharonov phases, yielding fractionally quantized recurrence times. However, the fractional quantization phenomenon in interacting quantum systems remains poorly explored. Here, we address this gap by establishing universal lower and upper bounds for recurrence times in interacting spins. Notably, we investigate scenarios where these bounds are approached, shedding light on the speed of quantum processes under monitoring. In specific cases, our findings reveal that the complex many-body system can be effectively mapped onto a dynamical system with a single quasi-particle, leading to the discovery of integer quantized recurrence times. Our research yields a valuable link between recurrence times and the number of dark states in the system, thus providing a deeper understanding of the intricate interplay between quantum recurrence, measurements, and interaction effects.

The hexatic phase is an intermediate stage in the melting process of a 2D crystal due to topological defects. Recently, this exotic phase was experimentally identified in the vortex lattice of 2D weakly disordered superconducting MoGe by scanning tunneling microscopic measurements. Here, we study this vortex state by the Nernst effect, which is an effective and sensitive tool to detect vortex motion, especially in the superconducting fluctuation regime. We find a surprising Nernst sign reversal at the melting transition of the hexatic phase. We propose that they are a consequence of vortex dislocations in the hexatic state which diffuse preferably from the cold to hot.

Surface polarization under harsh electrochemical environments usually puts catalysts in a thermodynamically unstable state, which strictly hampers the thermodynamic stability of Pt-based catalysts in high-performance fuel cells. Here, we report a strategy by introducing electron buffers (variable-valence metals, M = Ti, V, Cr, and Nb) into intermetallic Pt alloy nanoparticle catalysts to suppress the surface polarization of Pt shells using the structurally ordered L10-M-PtFe as a proof of concept. Operando X-ray absorption spectra analysis suggests that with the potential increase, electron buffers, especially Cr, could facilitate an electron flow to form a electron-enriched Pt shell and thus weaken the surface polarization and tensile Pt strain. The best-performing L10-Cr-PtFe/C catalyst delivers superb oxygen reduction reaction (ORR) activity (mass activity = 1.41/1.02 A mgPt–1 at 0.9 V, rated power density = 14.0/9.2 W mg …

The development of durable platinum-group-metal-free oxygen reduction reaction (ORR) catalysts is a key research direction for enabling the wide use of fuel cells. Here, we use a combination of experimental measurements and density functional theory calculations to study the activity and durability of seven iron-based metallophthalocyanine (MPc) ORR catalysts that differ only in the identity of the substituent groups on the MPcs. While the MPcs show similar ORR activity, their durabilities as measured by the current decay half-life differ greatly. We find that the energy difference between the hydrogenated intermediate structure and the final demetalated structure (ΔEdemetalation) of the MPcs is linearly related to the degradation reaction barrier energy. Comparison to the degradation data for the previously studied metallocorrole systems suggested that ΔEdemetalation also serves as a descriptor for the corrole …

The ramp reversal memory (RRM) effect that appears in thin films with temperature-driven insulator-metal transitions (IMTs) is a nonvolatile memory effect induced by a simple reversal of temperature ramping from heating to cooling during the phase-coexistence state of the IMT (when both metallic and insulating domains coexist). The memory of specific temperatures can be recorded by this ramp reversal, which appears as a resistance increase around the reversal temperatures. Previous studies showed RRM in , and , indicating it is a general effect in relevant systems. These studies indicate the RRM originates from an increase in the critical temperature around phase boundaries of the coexisting metallic and insulating domains during the temperature ramp reversal. However, the physical mechanism responsible for the increase remains elusive. To enhance our understanding of the effect and provide …

Rechargeable alkaline zinc–air batteries (ZAB) hold great promise as a viable, sustainable, and safe alternative energy storage system to the lithium‐ion battery. However, the practical realization of ZABs is limited by their intrinsically low energy trip efficiency, stemming from a large charge and discharge potential gap. This overpotential is attributed to the four‐electron oxygen evolution and reduction reactions and their sluggish kinetics. Here, a new concept based on two‐electron generation and consumption of hydrogen peroxide at the air electrode is introduced. The O2/peroxide chemistry, facilitated by a newly developed Ni‐based bifunctional electrocatalyst, enables fast peroxide generation/consumption, exceptional energy efficiency, high durability, and high capacity. Hence, this new design offers substantial progress toward the commercialization of high energy density metal–air batteries.

A major hypothesis for the etiology of type 1 diabetes (T1D) postulates initiation by viral infection, leading to double-stranded RNA (dsRNA)-mediated interferon response and inflammation; however, a causal virus has not been identified. Here, we use a mouse model, corroborated with human islet data, to demonstrate that endogenous dsRNA in beta cells can lead to a diabetogenic immune response, thus identifying a virus-independent mechanism for T1D initiation. We found that disruption of the RNA editing enzyme adenosine deaminases acting on RNA (ADAR) in beta cells triggers a massive interferon response, islet inflammation, and beta cell failure and destruction, with features bearing striking similarity to early-stage human T1D. Glycolysis via calcium enhances the interferon response, suggesting an actionable vicious cycle of inflammation and increased beta cell workload.

The non-Markovian continuous-time random walk model, featuring fat-tailed waiting times and narrow distributed displacements with a non-zero mean, is a well studied model for anomalous diffusion. Using an analytical approach, we recently demonstrated how a fractional space advection diffusion asymmetry equation, usually associated with Markovian Lévy flights, describes the spreading of a packet of particles. Since we use Gaussian statistics for jump lengths though fat-tailed distribution of waiting times, the appearance of fractional space derivatives in the kinetic equation demands explanations provided in this manuscript. As applications we analyse the spreading of tracers in two dimensions, breakthrough curves investigated in the field of contamination spreading in hydrology and first passage time statistics. We present a subordination scheme valid for the case when the mean waiting time is finite and the …

Cobalt toxicity is difficult to detect and therefore often underdiagnosed. The aim of this study was to explore the pathophysiology of cobalt-induced oxidative stress in the brain and its impact on structure and function. Thirty-five wild-type C57B16 mice received intraperitoneal cobalt chloride injections: a single high dose with evaluations at 24, 48, and 72 h (n= 5, each) or daily low doses for 28 (n= 5) or 56 days (n= 15). A part of the 56-day group also received minocycline (n= 5), while 10 mice served as controls. Behavioral changes were evaluated, and cobalt levels in tissues were measured with particle-induced X-ray emission. Brain sections underwent magnetic resonance imaging (MRI), electron microscopy, and histological, immunohistochemical, and molecular analyses. High-dose cobalt caused transient illness, whereas chronic daily low-dose administration led to long-term elevations in cobalt levels …

TiO2 material has gained significant attention for large‐scale energy storage due to its abundant, low‐cost, and environmentally friendly properties, as well as the availability of various nanostructures. Phosphorus doping has been established as an effective technique for improving electronic conductivity and managing the slow ionic diffusion kinetics of TiO2. In this study, non‐doped and phosphorus doped TiO2 materials were synthesized using sodium alginate biopolymer as chelating agent. The prepared materials were evaluated as anode materials for lithium‐ion batteries (LIBs). The electrodes exhibit remarkable electrochemical performance, including a high reversible capacity of 235 mAh g−1 at 0.1 C and excellent first coulombic efficiency of 99 %. An integrated approach, combining operando XRD and ex‐situ XAS, comprehensively investigates the relationship between phosphorus doping, material …

We propose a method to extract the upper laser level’s (ULL’s) excess electronic temperature from the analysis of the maximum light output power (P max) and current dynamic range ΔJ d = (J max − J th) of terahertz quantum cascade lasers (THz QCLs). We validated this method, both through simulation and experiment, by applying it on THz QCLs supporting a clean three-level system. Detailed knowledge of electronic excess temperatures is of utmost importance in order to achieve high temperature performance of THz QCLs. Our method is simple and can be easily implemented, meaning an extraction of the excess electron temperature can be achieved without intensive experimental effort. This knowledge should pave the way toward improvement of the temperature performance of THz QCLs beyond the state-of-the-art.

We hereby offer a comprehensive analysis of various factors that could potentially enable terahertz quantum cascade lasers (THz QCLs) to achieve room temperature performance. We thoroughly examine and integrate the latest findings from recent studies in the field. Our work goes beyond a mere analysis; it represents a nuanced and comprehensive exploration of the intricate factors influencing the performance of THz QCLs. Through a comprehensive and holistic approach, we propose novel insights that significantly contribute to advancing strategies for improving the temperature performance of THz QCLs. This all-encompassing perspective allows us not only to present a synthesis of existing knowledge but also to offer a fresh and nuanced strategy to improve the temperature performance of THz QCLs. We draw new conclusions from prior works, demonstrating that the key to enhancing THz QCL temperature …

The development of new nanoparticle-based antibiotics with biocompatible properties is an emerging advance in nanotechnology. This study advocated the development of carbon dots (CDs) doped with nitrogen, nitrogen with sulfur, and nitrogen with boron (N, NS, and NB-CDs). This led to changes in the properties of the CDs, both chemically and biologically. A facile hydrothermal technique was used to synthesize CDs and the formation of CDs was confirmed through various analytical techniques. The CDs had sizes ranging from 3.2 – 4.8 nm and ζ-potential values of +13 to 27 mV. The doped CDs exhibited moderate changes in fluorescence behaviors depending on the excitation wavelength (λex). The N- and NB-doped CDs were effective at eliminating gram-negative pathogens (E. coli and K. pneumoniae), with minimum inhibitory concentrations (MIC) of 300 µg/mL and 400 µg/mL, respectively. The …

Platinum group metal (PGM)-free catalysts are promising candidates to replace PGM catalysts for the oxygen reduction reaction in fuel cells. While methodologies to determine the number of active sites are under intense development, experimentally quantifying the parameters governing the kinetics of the reaction remains rare, albeit its potential for paving the pathways for future catalysts development. The use of transient voltammetry to probe electrocatalytic reactions by varying the measurement timescales and quantifying the reaction parameters via detailed microkinetic models has shown immense success in uncovering hidden mechanistic insights, connecting theory and experiments. Here we present the application of Fourier-transformed alternating-current voltammetry for analysis of the oxygen reduction reaction electrocatalysis on a model PGM-free catalyst, iron-phthalocyanine, to decipher the kinetic and …

In this era of advanced technology and innovation, infectious diseases still cause significant morbidity and mortality, which need to be addressed. Despite overwhelming success in the development of vaccines, transmittable diseases such as tuberculosis and AIDS remain unprotected, and the treatment is challenging due to frequent mutations of the pathogens. Formulations of new or existing drugs with polymeric materials have been explored as a promising new approach. Variations in shape, size, surface charge, internal morphology, and functionalization position polymer particles as a revolutionary material in healthcare. Here, an overview is provided of major diseases along with statistics on infection and death rates, focusing on polymer-based treatments and modes of action. Key issues are discussed in this review pertaining to current challenges and future perspectives.

We hereby offer a comprehensive analysis of various factors that could potentially enable terahertz quantum cascade lasers (THz QCLs) to achieve room temperature performance. We thoroughly examine and integrate the latest findings from recent studies in the field. Our work goes beyond a mere analysis; it represents a nuanced and comprehensive exploration of the intricate factors influencing the performance of THz QCLs. Through a comprehensive and holistic approach, we propose novel insights that significantly contribute to advancing strategies for improving the temperature performance of THz QCLs. This all-encompassing perspective allows us not only to present a synthesis of existing knowledge but also to offer a fresh and nuanced strategy to improve the temperature performance of THz QCLs. We draw new conclusions from prior works, demonstrating that the key to enhancing THz QCL temperature …

The development of new nanoparticle-based antibiotics with biocompatible properties is an emerging advance in nanotechnology. This study advocated the development of carbon dots (CDs) doped with nitrogen, nitrogen with sulfur, and nitrogen with boron (N, NS, and NB-CDs). This led to changes in the properties of the CDs, both chemically and biologically. A facile hydrothermal technique was used to synthesize CDs and the formation of CDs was confirmed through various analytical techniques. The CDs had sizes ranging from 3.2 – 4.8 nm and ζ-potential values of +13 to 27 mV. The doped CDs exhibited moderate changes in fluorescence behaviors depending on the excitation wavelength (λex). The N- and NB-doped CDs were effective at eliminating gram-negative pathogens (E. coli and K. pneumoniae), with minimum inhibitory concentrations (MIC) of 300 µg/mL and 400 µg/mL, respectively. The …

The development of new nanoparticle-based antibiotics with biocompatible properties is an emerging advance in nanotechnology. This study advocated the development of carbon dots (CDs) doped with nitrogen, nitrogen with sulfur, and nitrogen with boron (N, NS, and NB-CDs). This led to changes in the properties of the CDs, both chemically and biologically. A facile hydrothermal technique was used to synthesize CDs and the formation of CDs was confirmed through various analytical techniques. The CDs had sizes ranging from 3.2 – 4.8 nm and ζ-potential values of +13 to 27 mV. The doped CDs exhibited moderate changes in fluorescence behaviors depending on the excitation wavelength (λex). The N- and NB-doped CDs were effective at eliminating gram-negative pathogens (E. coli and K. pneumoniae), with minimum inhibitory concentrations (MIC) of 300 µg/mL and 400 µg/mL, respectively. The …

Identifying the type of structural defects and determining their concentration is crucial for effective defect engineering strategies since they govern various physical, chemical, and optoelectronic properties of graphene. Here, we study the effects of Ga ion irradiation on freestanding monolayer graphene, specifically focusing on the behavior of three defect-induced Raman lines (D, D' and (D+ D')). By employing a modified approach of the local activation model, we determine the key defect parameters of each line and show their dependence on different vibrational configurations of the iTO and iLO phonons emitted during scattering. The redshift of the lines and the broadening of their width, observed with an increase in the concentration of radiation defects over Nd ≈ 1013cm−2, are explained by the tensile stress of the graphene film and a decrease in the phonon lifetime, respectively. The resulting intensity ratio I(D)/I …