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We study the magneto-optical properties of Dirac semimetal (DSM) slabs with particular emphasis on Cd 3 As 2 through electron–photon–phonon interactions, focusing on the magneto-optical absorption coefficient (MOAC) and full-width at half maximum (FWHM). Studying the Landau level (LL) energy of DSMs in the (x y) plane and the z -direction revealed a unique deviation from the square root dependence on the magnetic field, distinguishing DSMs from other semiconductors. At high magnetic fields, the electron–hole symmetry in the LL spectrum is broken, indicating a topological phase in DSMs. For undoped DSMs, MOAC is driven by interband transitions, with peaks from one-photon absorption being smaller and positioned to the left of two-photon ones. Increasing the magnetic field increases peak values. FWHM for one- and two-photon processes increases with the magnetic field and follows a T dependence on temperature. In doped DSMs, both intraband and interband transitions occur, with new interband peaks emerging at higher temperatures near the Fermi energy. Increased electron density shifts the peak position slightly toward higher energy. Peaks from optical phonon emission are consistently higher and located to the right of those from optical phonon absorption, indicating a stronger emission process. The FWHM data allow for the estimation of electron mobilities, and using a reasonable broadening parameter, our predicted mobility values agree with experimental results. [ABSTRACT FROM AUTHOR]

In this work, we derive the analytical expression of Helmholtz free energy, mean nearest neighbor distance between two atoms, lattice constant, and molar volume using statistical moment method (SMM). Then, we present how to determine the melting temperature of cubic perovskite at high pressures by combining SMM and work-heat equivalence principle. The results of the melting theory of cubic perovskite are applied to two perovskites MgSiO 3 and CaSiO 3 under extreme conditions of the Earth's lower mantle. Our obtained melting curves of MgSiO 3 up to 1400 GPa and CaSiO 3 up to 136 GPa were compared with available experiment and other calculations and were in good agreement. The present study provides an effective theoretical tool for finding the melting curves of strongly anharmonic materials under extreme conditions. Our theoretical calculations would be helpful to clarify geological formation process at the Earth's lower mantle. [ABSTRACT FROM AUTHOR]

Background: To meet the World Health Organization goal of reducing physical inactivity by 15% by 2030, a multisectoral system approach is urgently needed to promote physical activity (PA). We report the process of and findings from a codesigned systems mapping project to present determinants of PA in the context of urban New South Wales, Australia. Methods: A participatory conceptual mapping workshop was held in May 2023 with 19 participants working in education, transportation, urban planning, community, health, and sport and recreation. Initial maps were developed and refined using online feedback from the participants. Interviews were conducted with 10 additional policymakers from relevant sectors to further refine the maps. Results: Two systems maps were cocreated, identifying over 100 variables influencing PA and their interconnections. Five settings emerged from the adults' map—social and community, policy, built environment and transportation, health care, and workplace—and 4 for the young people's map—family, school, transportation, and community and environment. The maps share similarities, such as regarding potential drivers within the transportation, community, and built environment sectors; however, the young people's map has a specific focus on the school setting and the adults' map on workplace and health care settings. Interviews with policymakers provided further unique insights into understanding and intervening in the PA system. Conclusions: This codesigned participatory systems mapping process, supplemented by stakeholder interviews, provided a unique opportunity to bring together stakeholders across sectors to understand the complexity within the PA system and begin to identify leverage points for tackling physical inactivity in New South Wales. [ABSTRACT FROM AUTHOR]

Objective: Passive stiffness, a biomechanical parameter, has a potential influence on running economy, thus playing a pivotal role in performance. This study aimed to quantify passive stiffness of the Achilles tendon and gastrocnemius muscle using myotonometry throughout an incremental running protocol. Methods: Twenty-one male participants underwent a multistage incremental test (Bordeaux test) on a treadmill until exhaustion. Passive stiffness of the gastrocnemius muscle and Achilles tendon was measured using a MyotonPRO device. Measurements were taken before, during, and after the incremental test. Results: Our findings indicated that passive stiffness of the medial gastrocnemius decreased at rest between prerun and postrun assessments (−20.12 N·m−1, P =.012). Furthermore, during the test, stiffness increased at low intensity (at 50% of maximal aerobic speed: +104.8 N·m−1, P =.042), returning to baseline values as intensity increased. Conclusions: Throughout an incremental running protocol, both Achilles tendon and gastrocnemius muscle stiffness initially increased and then decreased with escalating percentages of maximal aerobic speed. A deeper understanding of stiffness in running can inform more effective recommendations for runners' strengthening and training. [ABSTRACT FROM AUTHOR]

Entropy stabilized oxide of MgNiCoCuZnO5, also known as J14, is a material of active research interest due to a high degree of lattice distortion and tunability. Lattice distortion in J14 plays a crucial role in understanding the elastic constants and lattice thermal conductivity within the single-phase crystal. In this work, a neuroevolution machine learning potential (NEP) is developed for J14, and its accuracy has been compared to density functional theory calculations. The training errors for energy, force, and virial are 5.60 meV/atom, 97.90 meV/Å, and 45.67 meV/atom, respectively. Employing NEP potential, lattice distortion, and elastic constants is studied up to 900 K. In agreement with experimental findings, this study shows that the average lattice distortion of oxygen atoms is relatively higher than that of all transition metals in entropy-stabilized oxide. The observed distortion saturation in the J14 arises from the competing effects of minimum site distortion, which increases with increasing temperature due to enhanced thermal vibrations, and maximum site distortion, which decreases with increasing temperature. Furthermore, a series of molecular dynamics simulations up to 900 K are performed to study the stress–strain behavior. The elastic constants, bulk modulus, and ultimate tensile strength obtained from these simulations indicate a linear decrease in these properties with temperature, as J14 becomes softer owing to thermal effects. Finally, to gain some insight into thermal transport in these materials, with the so-developed NEP potential, and using non-equilibrium molecular dynamics simulations, we study the lattice thermal conductivity (κ) of the ternary compound MgNiO2 as a function of temperature. It is found that κ decreases from 4.25 W m − 1 K − 1 at room temperature to 3.5 W m − 1 K − 1 at 900 K. This suppression is attributed to the stronger scattering of low-frequency modes at higher temperatures. [ABSTRACT FROM AUTHOR]

Anion photoelectron spectra of ThSO− and ThS2− were recorded using the third (355 nm) harmonic of an Nd-YAG laser; these provided the measured vertical detachment energies of each anion. The experiments are supported by extensive coupled cluster calculations on ThSO, ThSO−, ThS2, and ThS2−, as well as the oxygen congeners ThO2 and ThO2−. The ab initio calculations, which included complete basis set extrapolations, spin–orbit effects using four-component coupled cluster, and higher-order correlation contributions through CCSDT(Q), yielded an adiabatic electron affinity for ThO2 that was within 0.02 eV of the previously determined experimental value. The singly occupied molecular orbital (SOMO) in all three anions corresponds primarily to the 7s orbital on Th. Successive substitution of S for each O in ThO2 leads to larger electron affinities and smaller bond angles in the neutral molecules, but larger angles in the anions. As demonstrated by Franck–Condon simulations of the spectra using the CCSD(T) spectroscopic constants, substitution of O by S significantly complicates the resulting detachment spectra due to the lower vibrational frequencies in the sulfur species. Overall the calculated vertical detachment energies are in very good agreement with the experiment. In addition to the adiabatic electron affinities of each species, atomization energies and heats of formation have also been determined via the FPD approach with expected uncertainties of 1–2 kcal/mol. [ABSTRACT FROM AUTHOR]

We perform large-scale atomistic simulations of a system containing 12 × 106 atoms, comprising an oxygen gas-filled bubble immersed in water, to understand the stability and cavitation induced by ultrasound. First, we propose a method to construct a bubble/water system. For a given bubble radius, the pressure inside the bubble is estimated using the Young–Laplace equation. Then, this pressure is used as a reference for a constant temperature, constant pressure simulation of an oxygen system, enabling us to extract a sphere of oxygen gas and place it into a cavity within an equilibrated water box. This ensures that the Young–Laplace equation is satisfied and the bubble is stable in water. Second, this stable bubble is used for ultrasound-induced cavitation simulations. We demonstrate that under weak ultrasound excitation, the bubble undergoes stable cavitation, revealing various fluid velocity patterns, including the first-order velocity field and microstreaming. These fluid patterns emerge around the bubble on a nanometer scale within a few nanoseconds, a phenomenon challenging to observe experimentally. With stronger ultrasound intensities, the bubble expands significantly and then collapses violently. The gas core of the collapsed bubble, measuring 3–4 nm, exhibits starfish shapes with temperatures around 1500 K and pressures around 6000 bar. The simulation results are compared with those from Rayleigh–Plesset equation modeling, showing good agreement. Our simulations provide insights into the stability and cavitation of nanosized bubbles. [ABSTRACT FROM AUTHOR]

Meso-scale calculations of energy localization and initiation in energetic material microstructures must capture the deformation and collapse of pores and high-temperature shear bands, which lead to hotspots. Because chemical reaction rates depend sensitively on temperature, predictive continuum models need to get the pore-collapse dynamics and resulting hotspot temperatures right; this imposes stringent demands on the fidelity of thermophysical model forms and parameters and on the numerical methods employed to perform high-resolution meso-scale calculations. Here, continuum material models for β-HMX are examined in the context of shock-induced pore collapse, treating predictions from all-atom molecular dynamics (MD) simulations as ground truth. Using atomistics-consistent material properties, we show that the currently available strength models for HMX fail to correctly capture pore collapse and hotspot temperatures. Insights from MD are then employed to advance a Modified Johnson–Cook (M-JC) strength model, which is shown to capture key aspects of the physics of shock-induced localization in HMX. The study culminates in a MD-guided strength model for β-HMX that produces continuum pore-collapse results in better alignment on several aspects with those predicted by MD, including pore-collapse mechanism and rate, shear-band formation in the collapse zone, and temperature, strain, and stress fields in the hotspot zone and the surrounding material. The resulting MD-informed/MD-determined M-JC model should improve the fidelity of meso-scale simulations to predict the detonation initiation of HMX-based energetic materials in microstructure-aware multi-scale frameworks. [ABSTRACT FROM AUTHOR]

A low-cost approach for stochastically sampling static exchange during time-dependent Hartree–Fock-type propagation is presented. This enables the use of an excellent hybrid density functional theory (DFT) starting point for stochastic GW quasiparticle energy calculations. Generalized Kohn–Sham molecular orbitals and energies, rather than those of a local-DFT calculation, are used for building the Green function and effective Coulomb interaction. The use of an optimally tuned hybrid diminishes the starting point dependency in one-shot stochastic GW, effectively avoiding the need for self-consistent GW iterations. [ABSTRACT FROM AUTHOR]

We investigate the application of matrix product state (MPS) representations of the influence functionals (IFs) for the calculation of real-time equilibrium correlation functions in open quantum systems. Focusing specifically on the unbiased spin-boson model, we explore the use of IF-MPSs for complex time propagation, as well as IF-MPSs for constructing correlation functions in the steady state. We examine three different IF approaches: one based on the Kadanoff–Baym contour targeting correlation functions at all times, one based on a complex contour targeting the correlation function at a single time, and a steady state formulation, which avoids imaginary or complex times, while providing access to correlation functions at all times. We show that within the IF language, the steady state formulation provides a powerful approach to evaluate equilibrium correlation functions. [ABSTRACT FROM AUTHOR]

Transporting ore from mines to ports is of significant interest in mining supply chains. These operations are commonly associated with growing costs and a lack of resources. Large mining companies are interested in optimally allocating resources to reduce operational costs. This problem has been previously investigated as resource constrained job scheduling (RCJS). While a number of optimisation methods have been proposed to tackle the deterministic problem, the uncertainty associated with resource availability, an inevitable challenge in mining operations, has received less attention. RCJS with uncertainty is a hard combinatorial optimisation problem that is challenging for existing optimisation methods. We propose an adaptive population-based simulated annealing algorithm that can overcome existing limitations of methods for RCJS with uncertainty, including pre-mature convergence, excessive number of hyper-parameters, and the inefficiency in coping with different uncertainty levels. This new algorithm effectively balances exploration and exploitation, by using a population, modifying the cooling schedule in the Metropolis-Hastings algorithm, and using an adaptive mechanism to select perturbation operators. The results show that the proposed algorithm outperforms existing methods on a benchmark RCJS dataset considering different uncertainty levels. Moreover, new best known solutions are discovered for all but one problem instance across all uncertainty levels. [ABSTRACT FROM AUTHOR]

Large-scale atomistic molecular dynamics (MD) simulations provide an exceptional opportunity to advance the fundamental understanding of carbon under extreme conditions of high pressures and temperatures. However, the fidelity of these simulations depends heavily on the accuracy of classical interatomic potentials governing the dynamics of many-atom systems. This study critically assesses several popular empirical potentials for carbon, as well as machine learning interatomic potentials (MLIPs), in their ability to simulate a range of physical properties at high pressures and temperatures, including the diamond equation of state, its melting line, shock Hugoniot, uniaxial compressions, and the structure of liquid carbon. Empirical potentials fail to accurately predict the behavior of carbon under high pressure–temperature conditions. In contrast, MLIPs demonstrate quantum accuracy, with Spectral Neighbor Analysis Potential (SNAP) and atomic cluster expansion (ACE) being the most accurate in reproducing the density functional theory results. ACE displays remarkable transferability despite not being specifically trained for extreme conditions. Furthermore, ACE and SNAP exhibit superior computational performance on graphics processing unit-based systems in billion atom MD simulations, with SNAP emerging as the fastest. In addition to offering practical guidance in selecting an interatomic potential with a fine balance of accuracy, transferability, and computational efficiency, this work also highlights transformative opportunities for groundbreaking scientific discoveries facilitated by quantum-accurate MD simulations with MLIPs on emerging exascale supercomputers. [ABSTRACT FROM AUTHOR]

Coated microbubbles are widely used in medical applications, particularly in enhanced drug and gene delivery. One of the mechanisms underlying these applications involves the shear stress exerted on the cell membrane by acoustic microstreaming generated through cavitation bubbles. In this study, we develop a novel simulation approach that combines the smooth dissipative particle dynamics (SDPD) simulation method with numerical modeling of the Rayleigh–Plesset-like equation in an ad hoc manner to simulate stable cavitation of microbubbles at microsecond and micrometer scales. Specifically, the SDPD method is utilized to model fluid dynamics, while the Rayleigh–Plesset-like equation is employed to describe bubble dynamics. Adopting a 1.5 μm coated microbubble driven by ultrasound with a frequency of 2 MHz and a pressure of 500 kPa as a representative example, we observe a high-velocity microstreaming pattern emerging around the bubble on a very small scale of a few micrometers after only a few microseconds. These spatiotemporal scales may pose challenges for experimental observation. The formation of this microstreaming arises from the opposing motion of the fluid layer next to the bubble and the fluid layers further away. Furthermore, our simulations reveal high shear stress levels of thousands of Pascals exerted on a wall located a few micrometers from the bubble. This contrasts with the shear stress values of a few Pascals calculated from theoretical models in the literature, which do not incorporate radial streaming into their theories. The implications of our results for bubble cavitation-induced pore formation on the cell membrane are discussed in some details. [ABSTRACT FROM AUTHOR]

This study examines the importance of governance quality of local government in small businesses' future revenue growth forecasting accuracy. Forecasting errors are due to either overestimation or under-estimation. When local governance quality improves, transaction costs are eliminated, boosting firms' actual performance up to the level forecast, thereby reducing overestimation. Also, when local governance quality improves, institutional trust (trust in government) and generalized trust (trust in strangers) improve, lifting the expectation of future performance to the actual level, thereby reducing under-estimation. We investigate these two mechanisms using a set of more than 250,000 small businesses in Vietnam using an instrumental variable approach to control for potential endogeneity. It is found that governance quality enhances forecasting accuracy by reducing under-estimation forecasting errors but, interestingly, without affecting overestimation errors. This paper is one of the first that links governance quality to business forecasting, indicating that local authorities can help local businesses make efficient resource preparation by improving their governance quality. [ABSTRACT FROM AUTHOR]

Background: There is limited evidence from globally diverse samples on the prevalence and correlates of meeting the global guideline of 180 minutes per day of total physical activity (TPA) among 3- to 4-year-olds. Methods: Cross-sectional study involving 797 (49.2% girls) 3- to 4-year-olds from 17 middle- and high-income countries who participated in the pilot phases 1 and 2 of the SUNRISE International Study of Movement Behaviours in the Early Years. Daily step count was measured using thigh-worn activPAL accelerometers. Children wore the accelerometers for at least one 24-hour period. Children were categorized as meeting the TPA guideline based on achieving ≥11,500 steps per day. Descriptive analyses were conducted to describe the proportion of meeting the TPA guideline for the overall sample and each of the sociodemographic variables, and 95% CIs were calculated. Multivariable logistic regression was used to determine the sociodemographic correlates of meeting the TPA guideline. Results: Mean daily step count was 10,295 steps per day (SD = 4084). Approximately one-third of the sample (30.9%, 95% CI, 27.6–34.2) met the TPA guideline. The proportion meeting the guideline was significantly lower among girls (adjusted OR [aOR] = 0.70, 95% CI, 0.51–0.96) and 4-year-olds (aOR = 0.50, 95% CI, 0.34–0.75) and higher among rural residents (aOR = 1.78, 95% CI, 1.27–2.49) and those from lower middle-income countries (aOR = 1.35, 95% CI, 0.89–2.04). Conclusions: The findings suggest that a minority of children might meet the TPA guideline globally, and the risk of not meeting the guideline differed by sociodemographic indicators. These findings suggest the need for more surveillance of TPA in young children globally and, possibly, interventions to improve childhood health and development. [ABSTRACT FROM AUTHOR]

This article is the first to study the relation between financial restatements and restatement firms' demand for trade credit as a source of financing. Using a sample of U.S.-listed firms for the 2000–2016 period, we find that restatement firms tend to use more trade credit in the year following the restatement disclosure year than do non-restatement firms. Moreover, we find evidence that restatement firms use trade credit to substitute for the reduced reliance on short- and long-term loans. Our further analysis reveals that restatement firms can obtain more trade credit when the firms promptly change the CEOs as a signal for firms' attempt to repair damaged organizational legitimacy. Taken together, our findings suggest that restatement firms experiencing difficulties in obtaining conventional borrowings tend to resort to trade credit as an alternative source of financing. [ABSTRACT FROM AUTHOR]

The microwave spectrum of 2,4-dimethylpyrrole was investigated using a Fourier-transform microwave spectrometer in a supersonic expansion. Torsional splittings arising from two inequivalent methyl internal rotors in combination with hyperfine splittings due to the nuclear quadrupole coupling of the 14N nucleus were observed. The experiments were accompanied by quantum chemical calculations. A total of 1561 rotational lines were assigned and fitted in global fits using the programs XIAM and BELGI-Cs-2Tops-hyperfine, both achieved the measurement accuracy of 4 kHz. Local separate fits were also performed to verify the correctness of the assignment. Accurate experimental molecular and internal rotation parameters could be deduced and compared to the calculated ones. The barrier to internal rotation of the 2-methyl rotor was determined to be 277.830(26) cm−1, essentially the same as the value of about 280 cm−1 found for 2-methylpyrrole but lower than the value of 317 cm−1 found for 2,5-dimethylpyrrole. The torsional barrier value of the 4-methyl rotor is 262.210(27) cm−1, slightly higher than the value of 246 cm−1 found for 3-methylpyrrole. Benchmarking the rotational constants for 2,4- and 2,5-dimethylpyrrole revealed that the MP2/6-31G(d,p) level could be helpful to guide the assignment of microwave spectra of pyrrole derivatives. [ABSTRACT FROM AUTHOR]

In this work, the Common Model of Multi-phase Strength and Equation of State (CMMP) model was applied to tin. Specifically, calibrations of the strength-specific elements of the CMMP foundation were developed with a combination of experiments and theory, and then the model was validated experimentally. The first element of the foundation is a multi-phase analytic treatment of the melt temperature and the shear modulus for the solid phases. These models were parameterized for each phase based on ab initio calculations using the software VASP (Vienna Ab initio Simulations Package) based on density functional theory. The shear modulus model for the ambient β phase was validated with ultrasonic sound speed measurements as a function of pressure and temperature. The second element of the foundation is a viscoplastic strength model for the β phase, upon which strength for inaccessible higher-pressure phases can be scaled as necessary. The stress–strain response of tin was measured at strain rates of 10 − 3 to 3 × 10 3 s − 1 and temperatures ranging from 87 to 373 K. The Preston–Tonks–Wallace (PTW) strength model was fit to that data using Bayesian model calibration. For validation, six forward and two reverse Taylor impact experiments were performed at different velocities to measure large plastic deformation of tin at strain rates up to 10 5 s − 1 . The PTW model accurately predicted the deformed shapes of the cylinders, with modest discrepancies attributed to the inability of PTW to capture the effects of twinning and dynamic recrystallization. Some material in the simulations of higher velocity Taylor cylinders reached the melting temperature, thus testing the multiphase model because of the presence of a second phase, the liquid. In simulations using a traditional modeling approach, the abrupt reduction of strength upon melt resulted in poor predictions of the deformed shape and non-physical temperatures. With CMMP, the most deformed material points evolved gradually to a mixed solid–liquid but never a fully liquid state, never fully lost strength, stayed at the melt temperature as the latent heat of fusion was absorbed, and predicted the deformed shape well. [ABSTRACT FROM AUTHOR]

Utilizing thermochemical reactions for thermal energy storage and solar fuel production has been an emerging research topic. Thermal transport properties of the materials are an important parameter that can determine the kinetics and efficiency of thermochemical reactions. With the increasing number of new thermochemical materials (TCMs); however, there is a lack of reliable techniques to monitor the thermal transport property of the materials and their changes as a function of reactions in real time. In this work, we report the in situ monitoring of thermochemical reactions using modulated photothermal radiometry (MPR). The thermal conductivities of two TCMs, namely, calcium hydroxide (Ca(OH)2) and Ba0.15Sr0.85FeO3−δ (BSF1585), were measured as a function of temperature and time using the MPR technique. The measured thermal conductivities were correlated to the reaction. The work has two significant contributions to the research communities. First, it provides a non-invasive diagnostic tool for monitoring the thermal transport properties of TCMs that can potentially be a high-throughput measurement technique conducive to optimizing TCMs, reactors, and related thermal systems. Second, for TCMs that show observable changes in thermal transport properties, a correlation between the measured thermal conductivity and the conversion fraction of the reaction can be established for monitoring the reaction kinetics based on thermal characterization. [ABSTRACT FROM AUTHOR]

A number of internal rotation codes can deal with the combination of one or two internal rotors with one 14N quadrupole nucleus, but once it comes to two 14N nuclei, no such code is available even for the case of one internal rotor. We present here the extension of our internal rotor program called BELGI-2N using the rho-axis method global approach to deal with compounds containing one methyl rotor and two weakly coupling 14N nuclei. To test our new code, we applied it to the microwave data recorded for N-methylimidazole, 2-methylimidazole, 4-methylimidazole, and 5-methylimidazole using a chirped-pulse Fourier transform microwave spectrometer in the 7.0–18.5 GHz frequency range. Compared to the previously published study, BELGI-2N was able to (i) significantly increase the number of assigned and fitted lines, (ii) fit the complete datasets considering both the internal rotation and the 14N nuclear quadrupole coupling effects simultaneously, and (iii) achieve standard deviations within the measurement accuracy for all methylimidazole isomers. [ABSTRACT FROM AUTHOR]

Pick-Up Points (PUPs) represent an alternative delivery option for online purchases. Parcels are delivered at a reduced cost to PUPs and wait until being picked up by customers or returned to the original warehouse if their sojourn time is over. When the chosen PUP is overloaded, the parcel may be refused and delivered to the next available PUP on the carrier tour. This paper presents and compares forecasting approaches for the load of a PUP to help PUP management companies balance delivery flows and reduce PUP overload. The parcel life-cycle has been taken into account in the forecasting process via models of the flow of parcel orders, the parcel delivery delays, and the pick-up process. Model-driven and data-driven approaches are compared in terms of load-prediction accuracy. For the considered example, the best approach (which makes use of the relationship of the load with the delivery and pick-up processes) is able to predict the load up to 4 days ahead with mean absolute errors ranging from 3.16 parcels (1 day ahead) to 8.51 parcels (4 days ahead) for a PUP with an average load of 45 parcels. [ABSTRACT FROM AUTHOR]

Using three exogenous shocks to ex ante litigation risk, including federal judge ideology and two influential judicial precedents, we find that lower shareholder litigation risk reduces a firm's propensity to delist from the U.S. stock markets. The effect is at least partially driven by indirect costs of litigation and that being a private firm can significantly reduce the threat of litigation. Overall, the results suggest that mitigating excessive litigation costs for public firms is crucial to ensure the continued vibrancy of the U.S. stock market. [ABSTRACT FROM AUTHOR]

This paper reports on the application of a near-infrared (NIR) imaging system for visualizing heat transfer dynamics from a bulk gadolinium (Gd) sample to the surrounding water during the magnetization/demagnetization process of the magnetocaloric effect (MCE). The suggested approach relied on the spectral variation in water absorption band at 1150 nm wavelength within the NIR spectrum. An experimental setup integrated a telecentric uniform-illumination system, a halogen lamp, and an NIR camera to enable real-time monitoring of a single magnetization and demagnetization cycle induced by an external magnetic field, which was generated by a permanent-magnet-based magnetic circuit. Two-dimensional absorbance images captured during this cycle clearly depicted the thermal energy generated by the MCE in water. Furthermore, an analysis of the thermal boundary layer and the quantification of heat transfer from Gd to water provided insights into the dynamics over time. These results indicated the potential of our NIR imaging techniques in optimizing thermal–fluid interactions within MCE systems, thereby improving the design and efficiency of magnetic refrigeration systems. [ABSTRACT FROM AUTHOR]

Wurtzite ScxAl1−xN/GaN (x = 0.13–0.18) multi-quantum wells grown by molecular beam epitaxy on c-plane GaN are found to exhibit remarkably strong and narrow near-infrared intersubband absorption in the technologically important 1.8–2.4 μm range. Band structure simulations reveal that, for GaN wells wider than 3 nm, the quantized energies are set by the steep triangular profile of the conduction band caused by intrinsic polarization fields. As a result, the intersubband transition energies provide unique and direct access to essential ScAlN polarization parameters. Measured infrared absorption indicates that the spontaneous polarization difference of the presumed lattice-matched Sc0.18Al0.82N/GaN heterostructure is smaller than the theoretically calculated value. The intersubband transition energies are relatively insensitive to the barrier alloy composition indicating negligible variation of the net polarization field in the probed 0.13–0.18 Sc composition range. [ABSTRACT FROM AUTHOR]

The projector augmented wave (PAW) method of Blöchl linearly maps smooth pseudo wavefunctions to the highly oscillatory all-electron DFT orbitals. Compared to norm-conserving pseudopotentials (NCPP), PAW has the advantage of lower kinetic energy cutoffs and larger grid spacing at the cost of having to solve for non-orthogonal wavefunctions. We earlier developed orthogonal PAW (OPAW) to allow the use of PAW when orthogonal wavefunctions are required. In OPAW, the pseudo wavefunctions are transformed through the efficient application of powers of the PAW overlap operator with essentially no extra cost compared to NCPP methods. Previously, we applied OPAW to DFT. Here, we take the first step to make OPAW viable for post-DFT methods by implementing it in real-time time-dependent (TD) DFT. Using fourth-order Runge–Kutta for the time-propagation, we compare calculations of absorption spectra for various organic and biological molecules and show that very large grid spacings are sufficient, 0.6–0.7 bohr in OPAW-TDDFT rather than the 0.4–0.5 bohr used in traditional NCPP-TDDFT calculations. This reduces the memory and propagation costs by around a factor of 3. Our method would be directly applicable to any post-DFT methods that require time-dependent propagations such as the GW approximation and the Bethe–Salpeter equation. [ABSTRACT FROM AUTHOR]

We set out to explore the unintended effects of human-machine moderation in mitigating harassment within online communities. We examine communities that use a block-list type bot to prevent harassment from the source of harassment. Drawing from social categorization and selective exposure theories, we theorize that employing a machine alongside humans for community moderation will create unintended adverse effects. Specifically, within the moderated focal community, we hypothesize an emboldening effect characterized by an increase in harassment among community members directed at their outgroup members. Additionally, we expect a disengaging effect, that is, a downward trend in the focal community's membership. Finally, in neighboring communities that share the same topic of discussion, we expect a spillover effect, that is, an increase in harassment. Employing Detoxify, a Bidirectional Encoder Representations from Transformers (BERT)-based model, we evaluate harassment scores in the focal community by analyzing 4 million Reddit comments across various communities. These scores serve as inputs for Bayesian Structural Time Series analysis, revealing evidence for both disengaging and spillover effects. For the emboldening effect, we use community-specific keywords in a predefined computer-assisted document classification approach, Keyword Assisted Topic Model (keyATM), to identify the target of harassment. We use mean comparison and regression discontinuity to assess the change in the level of harassment targeting outgroup members before and after the human-machine moderation implementation. [ABSTRACT FROM AUTHOR]

Blockchain (BC) applications in supply chain management (SCM) have recently received extensive attention. It is important to synthesise the extant literature on the field to identify key research themes and navigate potential future directions. This study thus develops an efficient, scalable data-driven review approach that uses text mining and Latent Dirichlet Allocation (LDA)-based topic modelling for automatic content analysis of full-text documents. Our method overcomes the drawbacks of traditional systematic literature reviews using either manual coding or bibliographic analysis for article classifications, which are highly time-consuming and biased when dealing with large amounts of text. 108 papers published between 2017 and 2022 were analysed which identified 10 key research themes, including revenue management, sustainability, traceability, manufacturing system, scheduling in cloud manufacturing, healthcare SCM, anti-counterfeit system, logistics and transportation, system architecture development, and food & agriculture SC. Five future directions are then suggested, including (1) integration of BC and other emerging technologies for global and scalable SCM, (2) crypto-X applications in SCM, (3) BC-enabled closed-loop SCM, (4) the environmental and social impacts of BC-based SCM and (5) decentralised autonomous organisations in SCM. [ABSTRACT FROM AUTHOR]

Alternating current (ac) losses in conductor-on-rounded-core (CORC) cables of YBCO high-temperature superconducting (HTS) tapes are a significant challenge in HTS power applications. This study employs two finite element analysis (FEA) models to investigate the contributions from different ac loss components and provide approaches for reducing ac losses in cables. An FEA model based on the T-A formulation treats the cross section of thin superconducting layers as 1D lines and, therefore, only can predict the ac loss generated by the perpendicular magnetic field. In contrast, the model based on H-formulation can be performed on the actual 2D rectangular cross section HTS tapes to provide the total ac losses generated by magnetic fluxes penetrating from both the edges and surfaces of HTS tapes, although this model requires more computing time and memory. The 1D and 2D simulation models were validated by cross comparing the results from both models and by comparing sub-section and full cross section models. Subsequently, two models relate cable design and operational parameters to the surface and edge losses of a two-layer CORC cable by considering the (1) relative contributions of edge and surface losses to the overall ac losses; (2) effect of the current distribution between inner and outer HTS layers on ac losses; (3) impact of the tape alignment on ac losses in each HTS layer; (4) influence of the thickness of HTS layers on ac losses; (5) effect of size and number of inter-tape gaps on ac losses; and (6) contribution frequency on the ac losses. The research results given in this paper are therefore not only valuable to suggest strategies for reducing ac loss in multi-layer cables but also for developing more accurate and effective methods to calculate ac loss in CORC HTS cables. [ABSTRACT FROM AUTHOR]

For the first time, this paper introduces a Fast Analysis and Prediction (FAP) approach for geometrically nonlinear bending analysis of plates and shells. The proposed approach consists of two phases: fast analysis and prediction using artificial neural networks (ANNs) combined with the Bayesian regularization algorithm. In the first phase (fast analysis), geometrically nonlinear bending analysis of a structure is performed using only several load steps. This enables the efficient computation within a short period of time. In the second phase (prediction using ANNs), the deflections obtained in the first phase are utilized as the data for training the ANNs. The trained networks are then used to quickly predict deflections at any load step. The calculation process in the second phase is also very fast. For the analysis package in the first phase, the formulation of this paper is originated from the literature for geometrically nonlinear analysis of composite shells. High accuracy and efficiency of the FAP approach were demonstrated via solving nonlinear bending problems of plates and shells including an isotropic square plate, a composite cylinder subjected to internal pressure, a FG-CNTRC panel and a pinched cylinder with end diaphragms. The proposed approach offers significantly computational savings (up to 70%) compared to the conventional one. ANNs combined with the Bayesian regularization algorithm, which are proposed for the FAP approach in this work, possess the outstanding advantages compared to many existing neural networks. The FAP approach can be applied to simulations, observations, or experiments where nonlinear responses are present or data is limited. Applying the FAP approach to such areas can significantly save labor, time, and money. [ABSTRACT FROM AUTHOR]

Two-dimensional materials and their combined heterostructures have paved the way for numerous next-generation electronic and optoelectronic applications. Herein, we performed first principles calculations to computationally design the MoSe2/WS2 heterostructure and consider its geometric structure, electronic properties and contact behavior, as well as the effects of the electric fields and strain. Our results show that the MoSe2/WS2 heterostructure is energetically, thermodynamically and mechanically stable. Depending on the stacking configurations, the MoSe2/WS2 heterostructure could form type-I or type-II band alignment. The versatility in contact behavior makes the MoSe2/WS2 heterostructure attractive in electronics and optoelectronics. The combination of the MoSe2/WS2 heterostructure also leads to an enhancement in the adsorption efficiency and the carrier mobility compared with the constituent components. More interestingly, our findings demonstrate that the electric field can induce the transition between type-I and type-II band alignments, as evident by the experimental measurement [J. Kistner-Morris, A. Shi, E. Liu, T. Arp, F. Farahmand, T. Taniguchi, K. Watanabe, V. Aji, C. H. Lui and N. Gabor, Nat. Commun., 2024, 15, 4075]. Additionally, we also find that strain can also induce the transition between type-I and type-II band alignments and lead to the transition from semiconductor to metal in the MoSe2/WS2 heterostructure. Our findings prove that the MoSe2/WS2 heterostructure holds significant potential for developing next-generation electronics. [ABSTRACT FROM AUTHOR]

Chitosan-magnetite nanocomposite (CM) was synthesised using the one-step procedure, reducing the synthesis time and the complexity of the process. The synthesized CM was characterised by using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET), vibrating sample magnetometer (VSM). The nanocomposite was used to remove eriochrome black T (EBT) from the aqueous solution. The effects of pH, adsorption time, initial concentration of EBT, dose, and temperatures were studied. The experiment data were analysed by pseudo-first-order, pseudo-second-order, Elovich, and intra-particle-diffusion kinetic models. Among these models, the pseudo-second-order was the best fit model and the adsorption rate constant of EBT was 0.007 g/mg.min. The adsorption isotherms were studied by fitting the experimental data to the Langmuir, Freundlich, and Temkin models. The results indicated that the Langmuir model was the fittest model for describing the isotherms of the EBT adsorption on CM. When the temperature increased from 293 to 313K, the maximum adsorption capacity of EBT decreased from 291.2 to 83.5 mg/g. The thermodynamic study showed that the ETB adsorption process onto CM was a spontaneous and exothermic process with ∆G0, ∆H0 negative. The EBT dye adsorption mechanism was discussed, involved interactions, such as electrostatic attraction and H-bonding. CM could be regenerated and reused to adsorb anionic dye. [ABSTRACT FROM AUTHOR]

To find a novel resin to remove Co(II), the adsorption behaviour of Co(II) from the simulated acid leaching solution was investigated by ion exchange with AG®50W-X4 resin. Parameters such as reaction time, HCl concentration, and resin concentration affected the loading efficiency of Co(II) by AG®50W-X4 resin were tested. The adsorption behaviour of Co(II) strongly depended on HCl and resin concentration while reaction time was little effect on the loading percentage of Co. The loading behaviour of Co(II) into the resin fitted well with the Langmuir adsorption isotherm and the loading capacity for Co(II) was found at 29.8 mg/g. Moderate HCl solution was effective in eluting Co(II) from the loaded AG®50W-X4 resin. The obtained results investigated that AG®50W-X4 resin was a promising resin to absorb Co(II) from the low acid leaching solution of the spent lithium-ion mobile phone batteries. [ABSTRACT FROM AUTHOR]

The well log data is represented as raw tabular data with diverse and nonlinear features. This poses a challenge for feature learning by machine learning models. The recent popular decision tree-based algorithms, such as random forest (RF), extreme gradient boosting (XGB) are prominent for learning nonlinear relationships of well log data in comparison with other methods of support vector machines (SVMs) and even deep learning models. In this work, we proposed using Tabnet model for direct learning tabular data of well logs. To our knowledge, this is the first time a state-of-the-art transformer-based model of Tabnet has been utilized for this task. The efficiency of Tabnet-based feature embedding is evaluated in two tasks of rock facies classification and learning feature embedding. We prove the efficiency of Tabnet model by experimental results on two small datasets of public Kansas dataset, which has nine wells for training and two wells for testing, and our own-built dataset, which has four wells for training and one well for testing. Although training on the modest amount of well log data, the proposed Tabnet model still promotes better classification efficiency than tree-based models of RF, XGBoost, LightGBM and deep learning models of MLP, CNN-1D, and ResNet-1D. KEY POINTS: Tabnet efficiency for facies classification and learning feature embedding from well log data. A challenge to learn these raw features directly for separating classes of facies. The superiority of the Tabnet network in comparison with other ruling tree-based methods and deep learning models. Facies classification and learning feature embeddings for categorical variables of well logs. [ABSTRACT FROM AUTHOR]

Nowadays, deep neural networks (DNNs) are helpful tools for mammogram classification in breast cancer screening. But, in Vietnam, there is a relatively small number of mammograms for training DNNs. Therefore, this study aims to apply transfer learning techniques to improve the performance of DNN models. In the first step, 10,418 breast cancer images from the Digital Database for Screening Mammography were used for training the CNN model ResNet 34. In the second step, we fine-tune this model on the Hanoi Medical University (HMU) database with 6,248 Vietnamese mammograms. The optimal model of ResNet 34 among these models achieves a macAUC of 0.766 in classifying breast cancer X-ray images into three Breast Imaging-Reporting and Data System (BI-RADS) categories, BI-RADS 045 ('incomplete and malignance'), BI-RADS 1 ('normal'), and BI-RADS 23 ('benign'), when tested on the test dataset. This result is higher than the result of the ResNet 50 model trained only on the X-ray dataset of 7,912 breast cancer images of the HMU dataset, which achieves a macAUC of 0.754. A comparison of the performance of the proposed model of ResNet 34 applying transfer learning with other works shows that our model's evaluation results are higher than those of the compared models. [ABSTRACT FROM AUTHOR]

In recent years, there has been extensive research on detecting damage or identifying changes in stiffness in structures by analyzing their dynamic properties or responses. The fundamental idea is that damage or loss of integrity in a structural system can affect its response to dynamic forces, leading to changes in properties like eigenfrequencies, modal damping ratios, mode shape, and transfer functions. In Vietnam and some other countries in the Southeast Asia region, the prevailing climate conditions, slow economic development, and geographical location have resulted in the construction of predominantly short-span bridges with a limited number of spans. This is primarily because these bridges connect small channels and waterways. This characteristic provides a basis for developing and applying research findings specifically for this group of bridges, as they are seldom encountered and researched in other countries worldwide. This paper presents a damage identification technique for short-span bridges based on changes in the representative power spectral density (RPSD) and the static moment of area (SSM). The proposed method is applied to experimental data obtained from various bridge models, including prestressed concrete, reinforced concrete, and composite steel bridges. It is important to note that changes in RPSD and SSM are independent of traffic conditions on the bridge but instead rely on the structural and material properties of the bridge spans. By utilizing RPSD and SSM, new advancements can be made in assessing the structural condition of bridges using vibration signals. [ABSTRACT FROM AUTHOR]

Road dust samples were collected from 6 cities and provinces in northern Vietnam to evaluate contamination levels and distribution characteristics of 5 toxic elements, including Cu, Zn, Pb, Cd, and As. Total concentrations of 5 elements in road dust samples ranged from 18.4 to 470 (median 96.4) mg/kg, in declining order of Zn > Cu > Pb > As > Cd. Pollution levels in urban road dust from Hanoi (median 266; range 205–366 mg/kg) were generally higher than those measured in samples taken from other industrial areas (median 91.1; range 18.4–470 mg/kg). Our results showed that the emission of some heavy metals from urban areas with high population density and heavy traffic was comparable to or even higher than in manufacturing areas of electronic components, construction materials, and mining. The chemical fractions of heavy metals in road dust were also evaluated. More than 60% of heavy metals are present in the potential mobile phases, indicating that the anthropogenic metals are still in a relatively weakly bound form. These metals can be mobile and bioaccumulative, affecting ecosystems and humans. The geological accumulation indexes indicate moderate contamination of heavy metals in many locations of this study. Cd poses an ecological threat in several urban and industrial sites. There were no serious human health risks associated with heavy metals in road dust. However, relatively high levels of Cu and Pb in road dust imply a health risk for children living in some urban and industrial areas. Further monitoring and risk assessment studies on toxic elements in road dust should be conducted, especially in developing countries' highly urbanised and industrialised areas. [ABSTRACT FROM AUTHOR]

Purpose: This study examines the impact of entrepreneurship education on the social entrepreneurship intentions of undergraduate students with a focus on the mediating effects of individual capital, such as human, social and cultural capital. Design/methodology/approach: This study adopted a quantitative approach with data collected from 392 third- and fourth-year students studying at a private university in Vietnam through a self-administered survey. The data were analysed using partial least squares structural equation modelling. Findings: The results show that entrepreneurship education positively impacts the social entrepreneurship intentions of undergraduate students. Furthermore, this study reveals that social and cultural capital serve as mediators in this relationship, whereas the mediating role of human capital was not supported. Practical implications: The study findings highlight the crucial role of higher education institutions in promoting and implementing formal entrepreneurship education. It also emphasises the importance of supporting enhancement of students' individual capital through social and cultural activities to foster their intentions to engage in social entrepreneurship. Originality/value: This study adds to the current literature on social entrepreneurship intentions by highlighting the significance of entrepreneurship education provided by universities and the roles of individual capital, such as social and cultural capital, in mediating the impact of entrepreneurship education on social entrepreneurship intentions. [ABSTRACT FROM AUTHOR]

Purpose: This research aims to identify the climate for innovation variables and to propose an innovative tool to quantitatively assess the degree of climate for innovation of construction firms. Design/methodology/approach: 14 climate-for-innovation variables were identified from a literature review and discussion with experienced practitioners. After that, a questionnaire survey was developed to collect data. Factor analysis was used to analyze data gathered from 157 completed responses. Then, fuzzy synthetic evaluation (FSE) was employed to assess the degree of climate for innovation in Vietnamese construction firms. Findings: Climate-for-innovation variables were categorized into four factors by factor analysis. The FSE analysis shows leadership is the most critical category of four factors, followed by working culture, organization and employee commitment. The calculation also illustrates that the climate for innovation in Vietnamese construction firms is at a moderate level. Originality/value: This research is one of the first integrated climate for innovation of construction firms in a comprehensive formulation. The formulation provides the decision-makers with a reliable tool to evaluate the degree of climate for innovation, thus having appropriate strategies to develop sustainable innovation performance within their organizations. [ABSTRACT FROM AUTHOR]

Owing to the challenges of antimicrobial resistance, investigations of new antibiotics from medicinal plants are continuously being conducted. Peperomia pellucida is a pantropical plant used in traditional medicine for the treatment of various disorders. From the ethanol extract of a whole P. pellucida plant, one previously undescribed carotane sesquiterpene (pellucarotine), one known carotane sesquiterpene (daucol), and one phenylpropanoid (dillapiol) were isolated and structurally elucidated. Their structures were determined based on 1D and 2D NMR, HR-ESI-Mass, experimental, and computational electronic circular dichroism spectroscopic data and compared with those reported in the literature. Antimicrobial assay results showed that pellucarotine had an anti-infective effect on Candida albicans with an MIC of 512 µg/mL. [ABSTRACT FROM AUTHOR]

This study elucidates to generate a linkage map for Portuguese oysters, Crassostrea angulata, and recognise potential markers linked to economical traits in C. angulata. Genome-wide association studies (GWAS) using 19,475 single nucleotide polymorphisms (SNPs) generated by a genotyping-by-sequencing approach consisting of 647 individuals in two selection generations of C. angulata, consisting of 57 full-sib family of the first generation and 33 full-sib family of the second generation. GWAS identified six significant SNPs linked to whole weight (P < 10−4). These six SNPs explained 10.2% of the total genetic variance of whole weight. Additionally, three SNPs were identified linked to meat yield (i.e., soft tissue weight) and contributed to 9.2% of the total genetic variance for this trait. By linkage analysis on the raw data, a total of 19,475 SNP markers were mapped to 10 linkage groups, with an average density of 19.1 SNPs per cM. This linkage map was developed and potential markers identified for whole weight and soft tissue weight provide a novel resource to characterise the genetic structure of economic traits in C. angulata. [ABSTRACT FROM AUTHOR]

This study aimed to elucidate the parasitic nematode infecting the bile ducts of striped catfish. A total of 1570 fish specimens, weighing between 400.5 and 899.1 g each, were examined. A parasitological analysis revealed that 607 fish samples were infected with nematodes, with typical clinical signs including swollen in both the common bile duct and gallbladder, several white cysts in the common bile ducts, and gallbladders exhibiting a dark green coloration. Examination of the common bile ducts in striped catfish revealed the presence of two distinct parasitic nematode morphotypes. Free-living nematodes were observed residing within the lumen, the central cavity, of the common bile duct. Additionally, larval nematodes were encapsulated within cysts lining the duct wall, suggesting a more chronic parasitic association. The infection rate of worms in the common bile duct was prevalent from November to April, with the most significant infection rate occurring in March (67.1%). The intensity of free-living nematode infection was the peak in March, with a mean of 6.7 ± 1.5 worm/gallbladder, and the peak level of larval nematode encapsulation was in November, with 9.4 ± 3.8 encysted larvae/common bile duct. The highest cumulative fish mortality rate was observed in February (2.1 ± 0.4%). Morphological analysis revealed the roundworms to be white and elongated with a slight narrowing at the mid-esophageal region. The mouth extended posteriorly towards the abdomen, and a well-developed, funnel-shaped esophagus was observed. Further analysis using 18S rRNA gene sequencing confirmed the identity of the parasite within the common bile duct of striped catfish as Cucullanus bourdini. [ABSTRACT FROM AUTHOR]

In this paper we prove the existence of optimal solutions as well as first-order necessary optimality conditions for a distributed optimal control problem governed by the three-dimensional viscous Camassa–Holm equations in bounded domains with the cost function of a quite general form. Particularly, in the box constraints case, the connection between the first-order necessary optimality conditions in the variational inequality form and the Pontryagin minimum principle is also established. [ABSTRACT FROM AUTHOR]

Seepage‐induced backward erosion is a complex and significant issue in geotechnical engineering that threatens the stability of infrastructure. Numerical prediction of the full development of backward erosion, pipe formation and induced failure remains challenging. For the first time, this study addresses this issue by modifying a recently developed five‐phase smoothed particle hydrodynamics (SPH) erosion framework. Full development of backward erosion was subsequently analysed in a rigid flume test and a field‐scale backward erosion‐induced levee failure test. The seepage and erosion analysis provided results consistent with experimental data, including pore water pressure evolution, pipe length and water flux at the exit, demonstrating the good performance of the proposed numerical approach. Key factors influencing backward erosion, such as anisotropic flow and critical hydraulic gradient, are also investigated through a parametric study conducted with the rigid flume test. The results provide a better understanding of the mechanism of backward erosion, pipe formation and the induced post‐failure process. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the total polyphenol content, antioxidant activity and tyrosinase inhibitory activity of ethanol/water extracts of rhizomes of Vietnamese Zingiber officinale, Curcuma longa, Alpinia officinarum Hance, and Boesenbergia pandurata (Roxb.) Schltr. Total polyphenol content was determined by the Folin–Ciocalteu method, antioxidant activity was evaluated through the DPPH (2,2-diphenyl-1-picryl hydrazyl) free radical scavenging method, and tyrosinase inhibitory activity was estimated using the substrate of 3,4-dihydroxy- L -phenylalanine (L -DOPA). Qualitative results showed that all ethanol/water extracts contained phenolic compounds. The total polyphenol content of the extracts was higher than that determined in previous research, of which the Zingiber officinale extract had the highest value (188.52 ± 2.52 mg GAE per g) and the Boesenbergia pandurata (Roxb.) Schltr extract (61.32 ± 1.72 mg GAE per g) had the lowest value. Compared with the positive control substances used, of the four extracts, the Zingiber officinale extract also showed the best ability to inhibit DPPH free radicals with IC50 = 35.04 ± 2.82 μg mL−1, and the Curcuma longa extract showed the best tyrosinase enzyme inhibition ability with IC50 = 26.07 ± 0.79 μg mL−1. [ABSTRACT FROM AUTHOR]

Single-atom-supported metal oxides have attracted extensive interest in energy catalysis, offering a promising avenue for mitigating greenhouse gas emissions and environmental pollution. This study presents a facile synthesis of single-atom Fe-modified Bi2WO6 photocatalysts. By carefully tuning the Fe ratios, the 1.5Fe-Bi2WO6 sample demonstrates exceptional photocatalytic efficiency in CO2 to CO reduction (36.78 μmol g−1). Additionally, an outstanding NO removal performance is also achieved through this photocatalyst with an impressively low conversion of toxic NO2 at just 0.37%. The reaction intermediates and mechanisms governing the photocatalytic reduction of CO2 into CO are elucidated using in situ DRIFTS and in situ XAS techniques. Regarding NO removal, the introduction of Fe single-atoms, along with induced oxygen vacancies, plays a pivotal role in facilitating the transformation of NO and NO2 into nitrate by stabilizing NO and NO2 species. Mechanistic insights into photocatalytic NO oxidation are garnered through scavenger trapping and EPR experiments employing DMPO. This study emphasizes single-atom-supported metal oxide's potential in sustainable chemistry and air purification, providing a promising solution for urgent environmental challenges. [ABSTRACT FROM AUTHOR]

We herein report the fabrication strategy of a robust catalyst for the formic acid electro-oxidation reaction (FAOR) via combining the advantages of a TiO2-related support and the synergistic effects of NiPtCo alloy. With the predominant dehydrogenation pathway, the NiPtCo/Ti0.7W0.3O2 catalyst shows remarkable FAOR mass activity and specific activity of 0.45 A mgMetal−1 and 1.25 mA cm−2, being 3.75- and 4.81-time higher than those of the commercially available Pt/C, respectively. The as-made FAOR electrocatalyst shows superior CO-tolerance and electrocatalytic stability during long-term operation conditions due to the synergistic contributions of each component in the overall catalyst system. [ABSTRACT FROM AUTHOR]