Changes In State Research Articles

Effect of Ar-ion irradiation on electrical transport of WS2 monolayer

Two-dimensional transition metal dichalcogenides (2D-TMDs), such as WS2 and MoS2, have attracted exceptional attention as promising materials for future optoelectronic systems due to their unique properties, including a direct band gap, high quantum efficiency, and flexibility. However, exploiting these materials’ potential in their pristine state remains a key challenge because of limited tunability and control over their properties. The introduction of crystal defects, such as vacancies and dopants, induces localized mid-gap states in 2D materials, enhances electrical transport, and creates a platform for tuning and exploiting these materials for practical applications. Our study explores the effect of Ar-ion beam irradiation on monolayer WS2, resulting in enhanced electrical transport compared to the pristine sample. We regulated the Ar-ion bombardment energy to vary the defect concentration from 0.1 to 0.5 keV. Photoluminescence (PL) and Raman investigations, revealed the extent of damage to the material. At the same time, x-ray photoelectron spectroscopy showed changes in the oxidation state with increasing irradiation energy. Our results demonstrated that Ar-ion treatment at low-energy irradiation enhanced electrical transport by ∼12 fold compared to pristine till 0.2 keV of irradiation by incorporating defects. However, higher irradiation energies reduced electrical transport due to increased disorder in the WS2 monolayer. This investigation highlights the potential for controlled defect engineering to optimize the properties of 2D-TMDs for practical applications.

Neuropilin-1 Protein May Serve as a Receptor for SARS-CoV-2 Infection: Evidence from Molecular Dynamics Simulations.

The binding of the virus to host cells is the first step in viral infection. Human cell angiotensin converting enzyme 2 (ACE2) is the most popular receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), while other receptors have recently been observed in experiments. Neuropilin-1 protein (NRP1) is one of them, but the mechanism of its binding to the wild type (WT) and different variants of the virus remain unclear at the atomic level. In this work, all-atom umbrella sampling simulations were performed to clarify the binding mechanism of NRP1 to the spike protein fragments 679-685 of the WT, Delta, and Omicron BA.1 variants. We found that the Delta variant binds most strongly to NRP1, while the affinity for Omicron BA.1 slightly decreases for NRP1 compared to that of WT, and the van der Waals interaction plays a key role in stabilizing the studied complexes. The change in the protonation state of the His amino acid results in different binding free energies between variants. Consistent with the experiment, decreasing the pH was shown to increase the binding affinity of the virus to NRP1. Our results indicate that Delta and Omicron mutations not only affect fusogenicity but also affect NRP1 binding. In addition, we argue that viral evolution does not further improve NRP1 binding affinity which remains in the μM range but may increase immune evasion.

Modulating the electronic structure of macroporous SrTiO3 through cobalt doping for enhance photocatalytic hydrogen evolution

The modulation of electronic structure plays a crucial role in enhancing the adsorption of H* for photocatalytic hydrogen evolution. In this study, we prepared a three-dimensionally ordered macroporous structure of cobalt doping SrTiO3 (Co/3DOMSTO) to provide a large specific surface area that exposes more active sites. The prepared catalysts exhibited the highest rate of photocatalytic hydrogen evolution, reaching 5892.86 μmol g−1 h−1, along with an apparent quantum efficiency (AQE) of approximately 2.4% under illumination at 427 nm. Additionally, the introduction of metal cobalt helped to modulate the electronic structure of Co/3DOMSTO and facilitate spatial charge separation. X-ray absorption fine structure (XAFS) and density functional theory (DFT) calculations were conducted to demonstrate that cobalt occupied the Ti sites on the surface of 3DOMSTO, resulting in changes in the electronic distribution state within space. This phenomenon facilitates the enrichment of electrons at the adjacent Ti sites, making the charge-rich Ti a new active site. These findings underscore the pivotal role played by the geometric configuration and tailored electronic structure of 3DOMSTO in augmenting its photocatalytic performance.

Deflection and control of the mixing region in membraneless vanadium micro redox flow batteries: Modeling and experimental validation

Membraneless micro redox flow batteries operate within the laminar flow regime to mitigate the convective mixing between catholyte and anolyte. The absence of an ion-exchange membrane reduces manufacturing costs and overall cell resistance, thereby enhancing battery performance. However, it also poses a new challenge: the precise control of the thin mixing layer established between the two co-flowing electrolytes. Undesired displacements of the mixing region lead to increased crossover losses and significant liquid transfer between tanks. This work addresses the deflection of the mixing region under varying flow conditions, considering electrolyte viscosity variations due to the changes in the local state of charge arising during battery operation. This is achieved through a combination of mathematical analysis, numerical simulations, and experimental results. The conservation equations and non-dimensional parameters governing the problem are first written and discussed. The model is then integrated numerically incorporating different inlet and outlet boundary conditions to simulate the effect of various flow control strategies. Next, the numerical results are validated against experimental realizations of the flow. Finally, three case studies are presented and discussed. This work highlights the relevance of variable viscosity in the operation of co-laminar membraneless micro redox flow batteries, and proposes for the first time feasible control methods to mitigate undesired disturbances in the hydraulic circuit, thereby minimizing crossover losses.

An analytical model of longitudinal joints in the segmental lining of shield tunnels with considering geometric nonlinearity

The previous mechanical analysis on the longitudinal joint of segmental linings commonly used the plane section assumption, in which the strains on the normal section are linearly and continuously distributed. This was proven to be overidealized according to a series of full-scale tests in existing literatures. In this paper, the nonlinear characteristics of deformation behavior for longitudinal joint were investigated with emphasis on the geometric nonlinearity of joint. A new analytical model of longitudinal joint was proposed with considering the geometric nonlinearity via employing the local plane section assumption to describe the strain distribution of joint section. The effectiveness of the proposed model was validated and parametric study (e.g. loading cycles and peak bending moment) was conducted. The results indicated the geometric nonlinearity of longitudinal joint refers to the increase area of free surface for the joint section. This nonlinearity will cause the discontinuous change of contact state which can be intuitively charactered by the height of concrete compression zone. Without considering the geometric nonlinearity, the area of concrete compression zone and bending capacity of the joint are overestimated by 45% to 100% based on the calculation result of the verification case. The increasing load cycles and peak load value deteriorate the deformation recoverability and ultimate capacity of joints. The degree of geometric nonlinearity is intensified with the increase of load cycles and peak load value but it can be alleviated if the concrete in external edge contact during overloading process.

Unveiling Key Interface Characteristics of Ni/Yttria-Stabilized Zirconia Solid Oxide Cell Electrodes in H2O Electroreduction Using Operando X-ray Photoelectron Spectroscopy.

Nickel/yttria-stabilized zirconia (YSZ) composites are the most commonly used fuel electrodes for solid oxide cells. While microstructural changes of Ni/YSZ during operational conditions have been thoroughly investigated, there is limited knowledge regarding Ni/YSZ surface chemistry under working conditions. In this study, we examine the interaction between Ni/YSZ electrodes and water vapor under open circuit and polarization conditions, utilizing near ambient pressure soft and hard X-ray photoelectron spectroscopies. Miniature cells with conventional porous Ni/YSZ composite cermet cathodes were modified to facilitate the direct spectroscopic observation of the functional electrode's areas close to the interface with the YSZ electrolyte. The results highlight dynamic changes in the oxidation state and composition of Ni/YSZ under H2 and H2O atmospheres. We also quantify the accumulation of impurities on the electrode surface. Through adjustments in the pretreatment of the cell, the correlation between the nickel surface oxidation state and the cell's electrochemical performance during H2O electroreduction is established. It is unequivocally shown that nickel surface oxidation in H2O electrolysis favors NiO over Ni(OH)x, providing critical insights into the mechanism of Ni-phase redistribution within the electrode during long-term operation. Depth-dependent photoemission measurements, combined with theoretical quantitative simulations, reveal that NiO and Ni phases are uniformly mixed on the surface during H2O electrolysis. This differs from the conventional expectation of a NiO-shell/Ni-core configuration in gas phase oxidation. These findings provide crucial insights into the surface chemistry of Ni/YSZ electrodes under conditions relevant to H2O electrolysis, elucidating their impact on the electrochemical performance of the cell.

Mechanoreception of pneumatic soft robotic finger without tactile sensor based on dual-position feature

Purpose Mechanoreception is crucial for robotic planning and control applications, and for robotic fingers, mechanoreception is generally obtained through tactile sensors. As a new type of robotic finger, the soft finger also requires mechanoreception, like contact force and object stiffness. Unlike rigid fingers, soft fingers have elastic structures, meaning there is a connection between force and deformation of the soft fingers. It allows soft fingers to achieve mechanoreception without using tactile sensors. This study aims to provide a mechanoreception sensing scheme of the soft finger without any tactile sensors. Design/methodology/approach This research uses bending sensors to measure the actual bending state under force and calculates the virtual bending state under assumed no-load conditions using pressure sensors and statics model. The difference between the virtual and actual finger states is the finger deformation under load, and its product with the finger stiffness can be used to calculate the contact force. There are distinctions between the virtual and actual finger state change rates in the pressing process. The difference caused by the stiffness of different objects is different, which can be used to identify the object stiffness. Findings Contact force perception can achieve a detection accuracy of 0.117 N root mean square error within the range of 0–6 N contact force. The contact object stiffness perception has a detection average deviation of about 15%, and the detection standard deviation is 10% for low-stiffness objects and 20% for high-stiffness objects. It performs better at detecting the stiffness of low-stiffness objects, which is consistent with the sensory ability of human fingers. Originality/value This paper proposes a universal mechanoreception method for soft fingers that only uses indispensable bending and pressure sensors without tactile sensors. It helps to reduce the hardware complexity of soft robots. Meanwhile, the soft finger no longer needs to deploy the tactile sensor at the fingertip, which can benefit the optimization design of the fingertip structure without considering the complex sensor installation. On the other hand, this approach is no longer confined to adding components needed. It can fully use the soft robot body’s physical elasticity to convert sensor signals. Essentially, It treats the soft actuators as soft sensors.

Modeling of Future Streamflow Hazards in Interior Alaska River Systems and Implications for Applied Planning

There is a growing need for proactive planning for natural hazards in a changing climate. Computational modeling of climate hazards provides an opportunity to inform planning, particularly in areas approaching ecosystem state changes, such as Interior Alaska, where future hazards are expected to differ significantly from historical events in frequency and severity. This paper considers improved modeling approaches from a physical process perspective and contextualizes the results within the complexities and limitations of hazard planning efforts and management concerns. Therefore, the aim is not only to improve the understanding of potential climate impacts on streamflow within this region but also to further explore the steps needed to evaluate local-scale hazards from global drivers and the potential challenges that may be present. This study used dynamically downscaled climate forcing data from ERA-Interim reanalysis datasets and projected climate scenarios from two General Circulation Models under a single Representative Concentration Pathway (RCP 8.5) to simulate an observational gage-calibrated WRF-Hydro model to assess shifts in streamflow and flooding potential in three Interior Alaska rivers over a historical period (2008–2017) and two future periods (2038–2047 and 2068–2077). Outputs were assessed for seasonality, streamflow, extreme events, and the comparison between existing flood control infrastructure in the region. The results indicate that streamflow in this region is likely to experience increases in seasonal length and baseflow, while the potential for extreme events and variable short-term streamflow behavior is likely to see greater uncertainty, based on the divergence between the models.

Goal Shifts Structure Memories and Prioritize Event-defining Information in Memory.

Every day, we encounter far more information than we could possibly remember. Thus, our memory systems must organize and prioritize the details from an experience that can adaptively guide the storage and retrieval of specific episodic events. Prior work has shown that shifts in internal goal states can function as event boundaries, chunking experiences into distinct and memorable episodes. In addition, at short delays, memory for contextual information at boundaries has been shown to be enhanced compared with items within each event. However, it remains unclear if these memory enhancements are limited to features that signal a meaningful transition between events. To determine how changes in dynamic goal states influence the organization and content of long-term memory, we designed a 2-day experiment in which participants viewed a series of black-and-white objects surrounded by a color border on a two-by-two grid. The location of the object on the grid determined which of two tasks participants performed on a given trial. To examine if distinct types of goal shifts modulate the effects of event segmentation, we changed the border color, the task, or both after every four items in a sequence. We found that goal shifts influenced the temporal memory in a manner consistent with the formation of distinct events. However, for subjective memory representations in particular, these effects differed by the type of event boundary. Furthermore, to examine if goal shifts lead to the prioritization of goal-relevant features in longer lasting memories, we tested the source memory for each object's color and grid location both immediately and after a 24-hr delay. On the immediate test, boundaries enhanced the memory for all concurrent source features compared with nonboundary items, but only if those boundaries involved a goal shift. In contrast, after a delay, the source memory was selectively enhanced for the feature relevant to the goal shift. These findings suggest that goals can adaptively structure memories by prioritizing contextual features that define a unique episode in memory.

Performance-Degradation Analysis of the Planetary Roller Screw Mechanism under Multi-Factor Coupling Effects

The performance-degradation pattern of the planetary roller screw mechanism (PRSM) is difficult to predict and evaluate due to a variety of factors. Load-carrying capacity, transmission accuracy, and efficiency are the main indicators for evaluating the performance of the PRSM. In this paper, a testing device for the comprehensive performance of the PRSM is designed by taking into account the coupling relationships among temperature rise, vibration, speed, and load. First, the functional design and error calibration of the testing device were conducted. Secondly, the PRSM designed in the supported project was taken as the research object to conduct degradation tests on its load-bearing capacity and transmission accuracy and analyze the changes in transmission efficiency. Third, the thread profile and wear condition were scanned and inspected using a universal tool microscope and an optical microscope. Finally, based on the monitoring module of the testing device, the vibration status during the PRSM testing process was collected in real time, laying a foundation for the subsequent assessment of the changes in the performance state of the PRSM. The test results reveal the law of performance degradation of the PRSM under the coupled effects of temperature, vibration, speed, and load.

A Developmental Mechanism to Regulate Alternative Polyadenylation in an Adult Stem Cell Lineage.

Alternative Cleavage and Polyadenylation (APA) often results in production of mRNA isoforms with either longer or shorter 3'UTRs from the same genetic locus, potentially impacting mRNA translation, localization and stability. Developmentally regulated APA can thus make major contributions to cell-type-specific gene expression programs as cells differentiate. During Drosophila spermatogenesis, approximately 500 genes undergo APA when proliferating spermatogonia differentiate into spermatocytes, producing transcripts with shortened 3' UTRs, leading to profound stage-specific changes in the proteins expressed. The molecular mechanisms that specify usage of upstream polyadenylation sites in spermatocytes are thus key to understanding the changes in cell state. Here, we show that upregulation of PCF11 and Cbc, the two components of Cleavage Factor II (CFII), orchestrates APA during Drosophila spermatogenesis. Knock down of PCF11 or cbc in spermatocytes caused dysregulation of APA, with many transcripts normally cleaved at a proximal site in spermatocytes now cleaved at their distal site, as in spermatogonia. Forced overexpression of CFII components in spermatogonia switched cleavage of some transcripts to the proximal site normally used in spermatocytes. Our findings reveal a developmental mechanism where changes in expression of specific cleavage factors can direct cell-type-specific APA at selected genes.

ОСОБЕННОСТИ ГУМУСНОГО СОСТОЯНИЯ ЧЕРНОЗЕМОВ ПРИ ОСВОЕНИИ ЗАЛЕЖИ

The purpose of the study is to determine the direction of change in the humus state of fallow soils in the forest-steppe zone when they are re-involved in arable land. The studies were carried out in the Kras-noyarsk forest-steppe during three growing seasons of 2015–2017 when the forb-grass deposit is replaced at the turf stage by agrocenosis of wheat and then by agrocenosis of pea-oat grass mixture. A distinctive feature of the process of involving fallow land in arable land was the chemical treatment of plants before plowing. Research has established that when the fallow is treated with herbicides and subsequent plowing, the sod horizon disappears, the amount of plant residues decreases sharply, the humus horizon differen¬tiates into arable and subarable with different densities, and blocky and dusty aggregates appear. The humus content under the long-term fallow land and during its plowing was high and amounted to 9.4–9.3 %; no decrease in humus was detected in the first two years after plowing, but the enrichment of humus with nitrogen decreased from an average to a very low level. The content of mobile humus in the soil under the long-term fallow land was 951 mg/100 g; when the fallow was plowed, it decreased to 346 mg/100 g. At the same time, the potential emission of carbon dioxide from agrochernozem increa¬sed – from 5.5 to 18.5 mg CO2 /10 g, which had an average inverse relationship with the SpO content (r = 0.56). It has been established that with intensive agrotechnical influence with the use of chemicals to destroy the turf horizon, the share of SPOs from Shumus decreases by more than 2.8 times due to its mineralization.

Impact of ocean in-situ observations on ECMWF sub-seasonal forecasts

We assess for the first time the impact of in-situ ocean observations on European Centre for Medium-Range Weather Forecasts (ECMWF) sub-seasonal forecasts of both ocean and atmospheric conditions. A series of coupled reforecasts have been conducted for the period 1993-2015, in which different sets of ocean observations were withdrawn in the production of the ocean initial conditions. Removal of all ocean in-situ observations in the initial conditions leads to significant degradation in the forecasts of ocean surface and subsurface mean state at lead times from week 1 to week 4. The negative impact is predominantly caused by the removal of the Argo observing system in recent decades. Changes in the mean state of atmospheric variables are comparatively small but significant in the forecasts of lower and upper atmospheric circulation over large regions. Our results highlight the value of continuous, real-time in-situ observations of the surface and subsurface ocean for coupled forecasts in the sub-seasonal range.

Impact of ocean in-situ observations on ECMWF sub-seasonal forecasts

We assess for the first time the impact of in-situ ocean observations on European Centre for Medium-Range Weather Forecasts (ECMWF) sub-seasonal forecasts of both ocean and atmospheric conditions. A series of coupled reforecasts have been conducted for the period 1993-2015, in which different sets of ocean observations were withdrawn in the production of the ocean initial conditions. Removal of all ocean in-situ observations in the initial conditions leads to significant degradation in the forecasts of ocean surface and subsurface mean state at lead times from week 1 to week 4. The negative impact is predominantly caused by the removal of the Argo observing system in recent decades. Changes in the mean state of atmospheric variables are comparatively small but significant in the forecasts of lower and upper atmospheric circulation over large regions. Our results highlight the value of continuous, real-time in-situ observations of the surface and subsurface ocean for coupled forecasts in the sub-seasonal range.

Об элементных фундаментах опор высоковольтных линий

Purpose: to substantiate the possibility of using the foundations of supports of high-voltage lines in the form of dispersed horizontal elements combined into a single structure for the perception of alternating loads. To determine by experimental and computational methods the effect of the mutual displacement of elements in the form of an increase in the bearing capacity of foundations and a decrease in their deformations under the influence of pressing and pulling loads. To show the possibility of replacing slab foundations of supports of high-voltage lines with structures made of prefabricated elements to reduce the volume and weight of products transported from the factory. Methods: application of the moire photogrammetric method to assess the development of soil compaction zones and angular deformations of the soil base in a tray with a glass wall under models of slab and elemental foundations. Using the method of boundary integral equations to obtain the dependence of precipitation on the step of elements for flexible and rigid foundations. Results: the effect of mutual influence of foundation elements during their convergence and dispersal in the form of a change in the stress-strain state in their base is illustrated. Differences in the depths of the distribution of compaction zones and areas of development of angular deformations are revealed. Quantitative data on the precipitation of slab and elemental foundations and the influence of the depth of the roof of the solid underlying layer on them have been obtained. Graphical dependences of the relationship of sediment elements with the distance (step) between them are presented. The effect of the division of the foundation on the rate of extinction of marginal tangential stresses in the base is shown. An illustration is made of an increase in the volume and surface area of the bulging body of the elemental foundation, which leads to an increase in its bearing capacity compared to the slab one when calculating for pulling out. Practical importance: the effectiveness of the use of an element foundation in comparison with the paid option in reducing the parameters of the stress-strain state of the base and facilitating logistical tasks during construction is shown. The experimental and computational methods used can be recommended for further refinement of the parameters of the elemental foundations.

Study on Safety Mining Technology of Gob in Stopping Face by Replacing Pressure Equalization with Gob Pumping—A Case Study of Sitai Mine

Gas control in the upper corner of the natural coal mining face with high gas is always a difficult problem that troubles the safe production of the working face. Among them, a high gas-prone natural coal mining face with ground air leakage is more likely to cause gas and CO to exceed limits in the corner of the working surface and is difficult to control. The traditional treatment methods often have some problems; for example, it is easy to increase air leakage in the gob with the method of gas extraction in the gob, which is not conducive to the prevention and control of spontaneous combustion of coal in the gob. At present, the more effective method is the pressure-equalization method. However, the pressure-equalization measures need to establish a complex pressure-equalization system, and close cooperation between the systems is required; once the system power fails or equipment failure occurs, the pressure-equalization state changes randomly, and it is easy to cause gas over-limits and other faults. Therefore, this paper presents a new method to control gas in the gob of a coal seam by pumping the gob of the upper-adjacent layer, using the negative pressure of pumping, and balancing the negative pressure of the upper-adjacent layer and the gob of the coal seam to form a new pressure-equalization relationship. This method can prevent the toxic and harmful gases in the goaf of the upper-adjacent layer from escaping into the passageway of the gob of the local coal seam, reduce the air leakage in the goaf, and benefit the gas control and spontaneous coal combustion prevention in the goaf.

Power scaling of intra-cavity Nd:YAG/LBO laser at 532 nm by birefringence compensation

We report an effective method to reduce the impact of polarization state changes caused by thermal birefringence in intra-cavity frequency-doubled laser. The laser consists of a diode side pumped Nd:YAG module, an acousto-optic modulator Q-switch, and an LBO crystal used for SHG generation in 532 nm laser. The effect of thermal birefringence originated by the Nd:YAG rod with concave-shape end surfaces on SHG efficiency is compensated by the insertion of a λ/8 plate into the cavity. At the repetition frequency of 9 kHz, the 532 nm laser achieves a maximum output power of 23.8 W, a pulse duration of 60 ns (FWHM), and a beam quality factor of Mx 2 × My 2 = 1.52 × 1.43. Compared with the λ/4 plate and without plate, the maximum average power of the laser with the λ/8 plate has increased by 22.7% and 66.4%, respectively, the beam quality factor has also been greatly improved correspondingly. This method provides a new solution for lasers to compensate thermally induced birefringence.

ScBoolSeq: Linking scRNA-seq statistics and Boolean dynamics.

Boolean networks are largely employed to model the qualitative dynamics of cell fate processes by describing the change of binary activation states of genes and transcription factors with time. Being able to bridge such qualitative states with quantitative measurements of gene expressions in cells, as scRNA-seq, is a cornerstone for data-driven model construction and validation. On one hand, scRNA-seq binarisation is a key step for inferring and validating Boolean models. On the other hand, the generation of synthetic scRNA-seq data from baseline Boolean models provides an important asset to benchmark inference methods. However, linking characteristics of scRNA-seq datasets, including dropout events, with Boolean states is a challenging task. We present scBoolSeq, a method for the bidirectional linking of scRNA-seq data and Boolean activation state of genes. Given a reference scRNA-seq dataset, scBoolSeq computes statistical criteria to classify the empirical gene pseudocount distributions as either unimodal, bimodal, or zero-inflated, and fit a probabilistic model of dropouts, with gene-dependent parameters. From these learnt distributions, scBoolSeq can perform both binarisation of scRNA-seq datasets, and generate synthetic scRNA-seq datasets from Boolean traces, as issued from Boolean networks, using biased sampling and dropout simulation. We present a case study demonstrating the application of scBoolSeq's binarisation scheme in data-driven model inference. Furthermore, we compare synthetic scRNA-seq data generated by scBoolSeq with BoolODE's, data for the same Boolean Network model. The comparison shows that our method better reproduces the statistics of real scRNA-seq datasets, such as the mean-variance and mean-dropout relationships while exhibiting clearly defined trajectories in two-dimensional projections of the data.

Impact of Transition Metal Layer Vacancy on the Structure and Performance of P2 Type Layered Sodium Cathode Material.

This study explores the impact of introducing vacancy in the transition metal layer of rationally designed Na0.6[Ni0.3Ru0.3Mn0.4]O2 (NRM) cathode material. The incorporation of Ru, Ni, and vacancy enhances the structural stability during extensive cycling, increases the operation voltage, and induces a capacity increase while also activating oxygen redox, respectively, in Na0.7[Ni0.2VNi0.1Ru0.3Mn0.4]O2 (V-NRM) compound. Various analytical techniques including transmission electron microscopy, X-ray absorption near edge spectroscopy, operando X-ray diffraction, and operando differential electrochemical mass spectrometry are employed to assess changes in the average oxidation states and structural distortions. The results demonstrate that V-NRM exhibits higher capacity than NRM and maintains a moderate capacity retention of 81% after 100 cycles. Furthermore, the formation of additional lone-pair electrons in the O 2p orbital enables V-NRM to utilize more capacity from the oxygen redox validated by density functional calculation, leading to a widened dominance of the OP4 phase without releasing O2 gas. These findings offer valuable insights for the design of advanced high-capacity cathode materials with improved performance and sustainability in sodium-ion batteries.

Corporate disclosure behavior during financial crises: Evidence from Korea

We examine corporate disclosure patterns according to changes in firm states during financial crises in Korea. Using panel data on Korean listed firms from 1995 to 2019, we first confirm that they transparently (opaquely) disclose information when the change in return on assets is positive (negative) during crises. Moreover, we check that these disclosure patterns increase debt financing but are ineffective for equity financing. Finally, for chaebols with internal capital markets, we find that internal capital receivers provide transparent (opaque) disclosure of negative (positive) changes in their states. By contrast, providers show the opposite patterns. (JEL G01, G30, M40)