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Co-delivery of chemotherapeutics and immunostimulant or chemoimmunotherapy is an emerging strategy in cancer therapy. The precise control of the targeting and release of agents is critical in this methodology. This article proposes the asynchronous release of the chemotherapeutic agents and immunostimulants to realize the synergistic effect between chemotherapy and immunotherapy. To obtain a proof-of-concept, a co-delivery system was prepared via a drug-delivering-drug (DDD) strategy for cytosolic co-delivery of Poly I:C, a synthetic dsRNA analog to activate RIG-I signaling, and PTX, a commonly used chemotherapeutics, in which pure PTX nanorods were sequentially coated with Poly I:C and mannuronic acid via stimulating the RIG-I signaling axis. The co-delivery system with a diameter of 200 nm enables profound immunogenicity of cancer cells, exhibiting increased secretion of cytokines and chemokines, pronounced immune response in vivo , and significant inhibition of tumor growth. Also, we found that intracellularly sustained release of cytotoxic agents could elicit the immunogenicity of cancer cells. Overall, the intracellular asynchronous release of chemotherapeutics and immunomodulators is a promising strategy to promote the immunogenicity of cancer cells and augment the antitumor immune response. Cytosolic delivery of Poly I:C to cancer cells induces robust immunostimulation via activating RIG-I pathway. Intracellularly sustaining release of cytotoxic agent significantly promotes immunogenicity of cancer cells. [Display omitted] [ABSTRACT FROM AUTHOR]

A novel method for predicting wind pressure time series on structures is proposed by combining long short-term memory network (LSTM) with proper orthogonal decomposition (POD). POD-LSTM predicts the pressure time series on any circumferential locations of a structure using data from limited pressure taps. The wind tunnel test data of pressure on a single square cylinder and the downstream cylinder of two tandem square cylinders is utilized to evaluate the performances of POD-LSTM, LSTM, and POD-BPNN (back-propagation neural network). Results of pressure time series, aerodynamic parameters, and pressure moments are presented. POD-LSTM takes advantage of LSTM in time series prediction and POD in extracting essential features, resulting in a better performance than POD-BPNN and LSTM. The similarity of pressure on nearby taps affects the accuracy of POD-LSTM. A larger error is observed at the rear corners of a single cylinder where intermittent flow reattachment occurs. The predicted results for mean and fluctuating pressure coefficients are satisfactory, but POD-LSTM underestimates the absolute value of skewness and kurtosis at structural surfaces where the non-Gaussian property of pressure is significant. Compared with the uniform flow condition, the prediction accuracy decreases when the structure is in the wake of upstream structures. • A novel method for predicting pressure time series was proposed by combining LSTM with POD. • POD-LSTM successfully predicts the pressure time series under uniform and characteristic wake inflow conditions. • Prediction error is relatively larger at non-Gaussian pressure regions on structures. [ABSTRACT FROM AUTHOR]

Materials used in hydrogen isotopes separation are crucial in modern hydrogen energy field. In this article, a promising material nanoporous palladium was prepared and its relative properties were studied. Nanoporous palladium with pore scale of about 5 nm was fabricated by free dealloying corrosion. Its kinetic and PCT curves of hydrogen/deuterium adsorption at room temperature were tested using a Sievert-type volumetric apparatus. Microstructures were observed with Scanning Electron Microscopy and Atomic Force Microscopy. Crystalline structure was characterized with X-Ray Diffractometer before and after deuterium adsorption. Comparative experiments with spongy palladium that is commonly used in relative industry were also carried out. According to the results, nanoporous palladium shows faster hydrogen/deuterium adsorption rate than spongy palladium, which is due to its nanoporous structure that supplies a large amount of specific surface area. PCT curves of hydrogen/deuterium adsorption in nanoporous palladium among 298–338 K were tested and plateau pressures at different temperatures were obtained. Deuterium/hydrogen isotopes separation factors were calculated using plateau pressures above and were plotted with temperature. It's found that nanoporous palladium shows larger hydrogen isotope separation factors compared with spongy palladium at temperatures no higher than 323 K. These findings illustrate that nanoporous palladium would be an ideal material for hydrogen isotopes separation applications. • Nanoporous palladium with pore scale of about 5 nm was fabricated. • Nanoporous palladium demonstrates fast hydrogen (deuterium) adsorption rate. • Nanoporous palladium shows large deuterium/hydrogen separation factor. • Nanoporous palladium makes a promising separation material for hydrogen isotopes. [ABSTRACT FROM AUTHOR]

Wind tunnel tests are conducted to study the aerodynamic characteristics of two identical square cylinders with variations in the incidence angle at a Reynolds number of Re = 8.0 × 104. The center-to-center spacing (P) ranges from 1.25 to 5.0 times the width of the cylinders (B), and the incidence angle (α) varies from 0° to 90°. The spacing ratio significantly influences the aerodynamics. When the two cylinders are very close, they can be treated as one bluff body for which the vortex sheds only at the wake of the downstream cylinder. With an increasing spacing ratio, the flow finally separates individually from the two cylinders and creates two related vortex shedding patterns. The interference effects of the two cylinders on the aerodynamics changes with an increasing spacing ratio. According to the aerodynamics, the arrangement of two identical square cylinders can be classified by the spacing ratio into three states: closely spaced (P/B < 1.5), moderately spaced (1.5 ≤ P/B ≤ 3) and widely spaced (3 < P/B ≤ 5). The characteristics of the aerodynamics and mechanism of interference effects in the three states are discussed, considering the influence of the incidence angles. • The aerodynamic forces of two identical square cylinders at various incidence angle were investigated in wind tunnel. • Three states were revealed by the spacing ratio:closely spaced state, moderately spaced state and widely spaced state. • The mechanism of interference is discussed based on the aerodynamic forces, pressure distributions, and Strouhal numbers. [ABSTRACT FROM AUTHOR]

CeO 2 thin films were deposited on stainless steel (SS) and indium tin oxide (ITO)-coated glass by simultaneous anodic and cathodic electrodeposition, and the influence of negative potential on the formation of ceria films was studied with scanning electron microscopy, X-ray diffraction, Raman spectroscopy, van der Pauw measurements, UV-visible spectroscopy and X-ray photoelectron spectroscopy. The results show that CeO 2 films on the anode are slightly affected by the potential, but the particle size, crystal orientation, strain, film thickness, resistivity and Ce(III) content of the films on the cathode increases with increasing potential on the SS substrate. Contradictory to the results of the SS cathode, redshift (E d changed from 3.95 eV to 3.56 eV and E i changed from 3.42 eV to 3.04 eV) occurring in the absorption spectrum of CeO 2 deposited on the ITO-coated glass cathode indicates that the content of Ce 3+ in the cathodic films is dependent on the adopted substrates and decreases as the applied potential is increased. [ABSTRACT FROM AUTHOR]

The extreme wind pressure might lead to local or overall structural failures. The physical mechanisms behind extreme pressures on two tandem square cylinders are investigated using large-eddy simulation at a Reynolds number of 8 × 104. The spacing ratio P/B ranges from 1.1 to 5 (P : cylinders' center distance; B : side length). The aerodynamic coefficients, flow patterns, mean and fluctuating pressure coefficients, pressure skewness and kurtosis, and instantaneous flow structures are analyzed. The extreme negative pressures are induced by the intermittent appearance of strong vortices attached to the cylinder surfaces. "Gap vortex" and "wall vortex" are responsible for the extreme pressure at the gap-sides of two cylinders in the single mode (1 < P / B < 2). "Corner vortex" would cause extreme negative pressure near the front corners of the upstream cylinder and the rear corners of both cylinders at most spacings. At the reattached (2 ≤ P / B < 4) and binary (4 ≤ P / B ≤ 5) modes, the Karman vortex released from the rear corner of the downstream cylinders leads to extreme pressure on the rear surface. As the spacing increases, the extreme pressure on non-Gaussian-pressure regions is generally strengthened but the three-dimensionality in vortex structures and instantaneous pressure distributions roughly declines. • Extreme negative pressures likely to be at corners and rear surfaces of twin prisms. • Intermittent attachment of strong vortices to surfaces causes extreme pressures. • Stronger extreme negative pressures at a larger spacing ratio. [ABSTRACT FROM AUTHOR]

Abstract: Eu2+/Dy3+ co-doped high silica glasses with different holding temperatures (T1) and the highest sintering temperatures (T2) were prepared. The emission spectra, infrared absorption spectra, and densities of glass samples show that T1 can greatly influence the shrinkage process of porous glass and T2 decides the residual content of OH groups in sintered samples, which are both important influencing factors on the luminescent properties. The Eu2+/Dy3+ co-doped high silica glass sintered at T1=800°C and T2=1000°C has the highest luminescent intensity for its least residual pores and OH groups. Besides, the theory of pore shrinkage was also referred to explain the experimental results. [Copyright &y& Elsevier]

Shape modification effectively reduces the wind loading and wind-induced vibrations of slender structures. Large-eddy simulation is used to investigate the flow around multiple square-like cylinders at a Reynolds number of 22,000. Based on a standard square cylinder, six square-like cylinders are simulated with sharp/rounded corners and straight/concave/convex sides. The combination of rounded corners and convex sides enables the best aerodynamic performance. Furthermore, a parametric study on the round-convex cylinder is conducted considering a fixed corner radius and various side curvatures B / K (B : nominal side length; K : side radius). The results show that both the aerodynamic characteristics of and the flow features around the cylinder change considerably with varying B / K and that three distinct flow regimes are observed. In Stage I (0 ≤ B / K ≤ 0.71), the flow separates at the front corners, and the aerodynamic forces decrease gradually. In Stage II (0.71 < B / K < 1.00), the shear layer separating at the front corner-side region reattaches to the lateral sides. The fluctuating coefficients rise at B / K = 0.74; thereafter, the aerodynamic forces drop and are minimized at B / K = 1.00. In Stage III (1.00 ≤ B / K ≤ 1.77), flow separates at the lateral sides, and the aerodynamic forces recover gradually. • Rounded corners and convex sides reduce the aerodynamic forces. • Three flow regimes are identified for the round-convex cylinder. • The side curvature B / K = 1.00 enables the best aerodynamic performance. [ABSTRACT FROM AUTHOR]

Wind tunnel experiments on flow interference of adjacent (spacing ratio P / B ​= ​1.75) twin square cylinders in various attack angles α were conducted at a Reynolds number of 8.0 ​× ​104 considering both horizontal and diagonal arrangements of models. Investigations on the mean and fluctuating aerodynamic force coefficients, mean and fluctuating wind pressure coefficients, spanwise correlations, power spectrum densities (PSD) of lift, and Strouhal numbers of two cylinders, as well as the inter-cylinder correlations between them, are presented. The results show that the aerodynamic characteristics of two diagonal cylinders differ significantly from those of horizontal ones. Compared with the single-cylinder, the pressure distributions on adjacent cylinders are dramatically changed, leading to the negative drag, attractive lift, or repulsive lift on the downstream cylinder. At small α , diagonal cylinders present stronger mean drag and higher fluctuating forces than horizontal cylinders do. Besides, a stronger spanwise correlation is found for the diagonal ones. The vortex shedding pattern can be divided into four stages for the horizontal arrangement and six for the diagonal case. PSD curves and Strouhal numbers are similar between two cylinders for both arrangements, suggesting that the two closely spaced cylinders act like one bluff body in the vortex shedding. • Horizontal and diagonal cylinders have quite different aerodynamic properties. • Two closely spaced square cylinders act like one bluff body in vortex shedding. • Negative drag and attractive lift on the downstream cylinder exist at α ​≤ ​30°. [ABSTRACT FROM AUTHOR]

This paper presents a numerical study of the flow around two static staggered circular cylinders at a high subcritical Reynolds number of Re = 1.4 × 105. The center-to-center pitch ratio (P/D) varied from 1.5 to 4, and the incidence angle (β) increased from 0° to 90°. Three critical aerodynamic phenomena at the downstream cylinder—negative drag force, inner lift force, and outer lift force—are successfully simulated. New explanations for the phenomena are proposed. The negative drag force appears at approximately P/D = 1.5–2 and β = 0°–10°, which is ascribed to a recirculation pair with opposite directions and a high-speed gap flow between the cylinders in the tandem and staggered configurations, respectively. The inner lift force happens at about P/D = 1.5–3 and β = 10°, which is due to the combined effects of a stagnation point shift, high-speed gap flow, and rising of the gap-side unsteady separation bubble at the downstream cylinder. The outer lift force occurs at about β = 20° and P/D = 3–4, which is attributed to a gap-side separation point shift from windward to leeward and interactions between the vortices shed from the upstream cylinder and the shear layer of the downstream cylinder. • The flow around two staggered circular cylinders is simulated at a high subcritical Reynolds number of 1.4 × 105. • The relationship between the aerodynamic characteristics and the flow features is established. • New explanations are proposed for the negative drag force, the inner lift force and the outer lift force of downstream cylinder. • The unsteady separation bubble contributes a lot to the inner lift force of the downstream cylinder. • The lower separation point of the downstream cylinder shifts downwards, which contributes to the outer lift force. [ABSTRACT FROM AUTHOR]

The present work investigates the vortex-induced vibration of twin square cylinders at Re = 150 with three restraint conditions. (Ⅰ) the upstream cylinder (UC) is free to oscillate while the downstream cylinder (DC) is fixed; (Ⅱ) both cylinders are free to oscillate, and (Ⅲ) the UC is fixed while the DC is free to oscillate. The centre-to-centre distance between the cylinders is fixed as 4.0 B , and the mass ratio of the cylinder is m * = 3. The computations are performed for the reduced velocity ranging from 1 to 15 under each restraint condition. The flow dynamics are described by the two-dimensional incompressible Navier-Stokes equations and solved numerically using the Ansys Fluent CFD code (based on the finite volume method and SIMPLEC algorithm. It is found that whether the DC oscillates, the UC will exhibit the soft-lock-in phenomenon within the co-shedding regime. At high reduced velocities, the UC re-shows the soft-lock-in phenomenon when the DC is fixed. Whether the UC oscillates, the DC will exhibit the soft-lock-in phenomenon within the reattachment regime. For Case-Ⅱ, the strong vortex falling off the leeward side of the UC leads to a sharp decrease in distance between the two cylinders, and the DC exhibits the soft-lock-in phenomenon again. • Restraint effect on the VIV of twin square cylinders enriches the relevant study. • The dynamic response, flow-induced force and Fluid-structure-interaction with staggered cases are analyzed systematically. • Twin cylinders are allowed to oscillate in streamwise and transverse directions freely. [ABSTRACT FROM AUTHOR]

Nanocrystalline ceria thin films have been prepared by photo-assisted anodic deposition in two kinds of solutions (water and 70% v/v ethanol-water) containing different sodium nitrate concentrations (0, 0.15, 0.20, 0.25 and 0.30 mol l − 1 ) onto 316L surface. The synergistic effect of nitrate content and ethanol on the formation of ceria films was studied with scanning electron microscopy, ellipsometry, X-ray diffraction, and Raman, UV–visible, and X-ray photoelectron spectroscopy. Results show that the current density, film thickness, particle size and Ce( IV ) content increase with increasing nitrate concentration in water solution whereas decrease in 70% v/v ethanol-water solution. When the nitrate concentration is higher than 0.25 mol l − 1 , the positive function of nitrate on the growth of ceria films is more prominent than ethanol. The action mechanism of nitrate on the photoelectrochemical deposition of CeO 2 in two different solutions has been discussed in details. [ABSTRACT FROM AUTHOR]

The uneven distribution of shear forces in shear connectors arranged in multiple rows and columns could cause issues of fatigue and durability in composite structures. In many practical applications, the shear connectors bear not only large shear forces but also considerable tensile forces. To improve the uneven shear distribution in perfobond connector (PBL) groups without significantly damaging their tensile performance, a new orthotropic rubber ring that can be easily installed on PBLs was proposed. Firstly, the tests for the tensile, shear, and combined tensile and shear behavior of PBLs embedded in ultra-high performance concrete (UHPC) with and without orthotropic rubber rings were conducted. The test results showed that orthotropic rubber rings could effectively reduce the shear stiffness of PBLs but inconsiderably affect the tensile performance. Secondly, a refined finite element (FE) model involving the fracture of perforating rebars was established and validated by the test results. The shear and tensile mechanisms of the new rubber ring PBLs were discussed. Further, a parametric study including 240 models was performed to investigate the effects of hole diameters, embedded depths, opening angles of rubber rings, and tensile force ratios. The results indicated that the shear capacity of PBLs decreased almost linearly with tensile force ratios. Finally, the shear capacity equation of PBLs under the effects of tensile forces and rubber rings was proposed by a regression analysis. Besides, an equivalent projected area method was proposed to derive the reduction factor of shear stiffness considering the effects of opening angles of rubber rings and tensile force ratios. • A new orthotropic rubber ring for PBLs can lower shear stiffness without damaging tensile performance. • Failure modes of PBLs embedded in UHPC under combined tensile and shear forces. • Capacity and stiffness equations of PBLs under combined tensile and shear forces. [ABSTRACT FROM AUTHOR]

Vortex-induced vibration (VIV) of twin square cylinders is numerically investigated at Re = 150 with tandem, staggered and side-by-side configurations. Three VIV categories are identified due to dynamic responses, flow-induced forces and flow fields. For Case-Ⅰ (α = 0°), two cylinders only display the typical synchronization region (the reduced velocity of the synchronization region, V r ≈ 5–6). The maximum transverse amplitudes of twin cylinders are 2 times and 2.4 times that of the single one (A y ,max = 0.3 B , B is cylinders' characteristic length), respectively. There is also sizable streamwise oscillation for Cylinder-2 (A x ,max = 0.48 B). Compared to Case-Ⅰ, streamwise and transverse amplitudes of twin cylinders systematically rise for Case-Ⅱ (α = 15°, 30°), where A y ,max and A x ,max of two cylinders is approximately 1.9 times and 2.9 times those in Case-Ⅰ, respectively. Two cylinders exhibit not only a typical synchronization region (V r ≈ 5–6) but also a non-typical synchronization region at high V r ≈ 10–12. Unlike the typical one, Cylinder-2 within the non-typical region shows stronger vortexes, more pronounced vibrations and lower fluctuating lift. For Case-Ⅲ (α = 45°–90°), the flow interference of twin square cylinders mainly occurs in the wake area and marginally affects the dynamic responses. The VIV characteristics of twin cylinders are similar to those of an isolated cylinder. • Configuration effect on the VIV of twin square cylinders enriches the relevant study. • The dynamic response, flow-induced force and Fluid-structure-interaction with staggered cases are analyzed systematically. • Twin cylinders are allowed to oscillate in streamwise and transverse directions freely. [ABSTRACT FROM AUTHOR]

Abstract: Luminescent properties of Ce/Tb/Eu co-doped calcium borosilicate glass were investigated through excitation and emission spectra, fluorescence lifetimes and colorimetric analysis. The spectra results show that the concentration quenching of Eu3+ ions occurs when the concentration of Eu2O3 ranges from 0.75mol% to 1.00mol% and Ce3+, Tb3+ and Eu2+ ions are all the donors which can transfer energy to Eu3+. It can be indicated from the analysis of lifetimes that through nonradiative transition, Tb3+ ions can accept energy from Eu2+ ions and also transfer energy to Eu3+ ions. Furthermore, the colorimetric analysis show that the correlated color temperatures (CCT) of Ce/Tb/Eu co-doped calcium borosilicate glass can be adjusted from cold white to warm white by controlling the concentration of Eu2O3. [Copyright &y& Elsevier]

In practical engineering, concrete structures typically undergo high temperatures and fire spray cooling during the process of fire, and high temperatures will cause changes in the microstructure of concrete. Therefore, studying the fracture mechanical properties of concrete after rapid cooling at high temperatures is more in line with the actual engineering situation. This paper sets five temperature conditions (20°C, 200°C, 400°C, 600°C, and 800°C), and after rapid cooling in a water bath, a hydraulic servo machine is used to conduct three-point bending beam fracture tests on plain concrete (PC) and high performance concrete (HPC). The fracture process and mechanism are analyzed using digital image correlation (DIC) and acoustic emission (AE). The research results indicate that the three-point bending unstable fracture load of PC and HPC decreases with the increase of temperature, with the maximum reduction after 800 ℃ high temperature, reaching 87.5% and 82.2%, respectively. After high temperature, the fracture energy of PC and HPC both showed a trend of first increasing and then decreasing. The ductility index of PC and HPC increases with the increase of temperature. The unstable fracture toughness and initial fracture toughness of PC and HPC decrease with the increase of temperature. By combining DIC and AE technologies, the development and fracture mode of cracks in PC and HPC after rapid cooling at high temperature are analyzed. The results showed that the softening effect of concrete is more significant after high temperature, the crack initiation stage is earlier, and the bearing capacity is lower. Furthermore, modern testing techniques are employed to reveal the mechanism of the impact of high temperature and cooling methods on the mechanical properties of HPC from a microscopic perspective. The research results have important reference value for practical engineering. • This study compares the fracture mechanical properties of PC and HPC after rapid high-temperature cooling. • The development process of HPC cracks after rapid high-temperature cooling is studied using DIC and AE techniques. • The mechanism of degradation of HPC fracture mechanical properties has been revealed through microscopic observation methods. [ABSTRACT FROM AUTHOR]

Different spacing cases (L / B = 2–6) are numerically examined to identify the spacing effect on the two-degree-of-freedom vortex-induced vibration (VIV) of two tandem square cylinders at Re = 150. According to the various vibration responses, force characteristics and flow patterns, spacing cases can be divided into three different situations. At a small spacing (L / B = 2, 2.5), the upstream cylinder (UC) has no traditional lock-in region (the frequency ratio f y / f n ≈ 0.95–1.05, and the reduced velocity V r ≈ 6), and the downstream cylinder (DC) has a narrow lock-in region. However, there is a wide soft-lock-in region (the synchronization region of f y / f n ≈ 0.85) at high reduced velocities (V r ≈ 9.5–12) for both cylinders. In this region, both cylinders experience large-amplitude transverse vibrations, with the UC exhibiting a higher amplitude. At a moderate spacing (L / B = 3, 4), the UC does not exhibit lock-in or soft-lock-in regions, similar to a single cylinder at the same mass ratio, and the DC exhibits a relatively wide lock-in region (V r ≈ 5.5–8) instead of a soft-lock-in region. Notably, two amplitude peaks appear within the lock-in region for the DC depending on V r. At a large spacing (L / B = 5, 6), the amplitude of the DC is typically higher than that of a single cylinder, even within the narrow lock-in region. • Spacing effect on the VIV of two tandem square cylinders enriches the relevant study. • Three different spacing situations with six operating cases are analyzed. • Degrees of freedom are selected as 2. [ABSTRACT FROM AUTHOR]

• Three failure modes of HSS perfobond connectors embedded in UHPC were found in the push-out test. • The effects of hole diameters, plate thicknesses, and steel grades on the transition condition of failure modes were investigated. • An analytical model for the shear capacity of PBLs considering the varying failure modes was proposed, which matched well with the 90 parametric study results. The application of advanced high-performance materials, such as High-Strength Steel (HSS) and Ultra-High Performance Concrete (UHPC), provides innovative concepts for structural designs. To implement lighter, longer-span, and more durable structures, composite structures consisting of HSS and UHPC have been paid more attention recently since their combination might fully develop the superiority of each. Although perfobond connectors (PBLs) were reported to have excellent behavior, most studies focused on the PBLs with conventional materials and dimensions. The failure modes of PBLs with a smaller size embedded in UHPC are unclear. Besides, the current interface design methods are for ordinary composite structures, which could cause an unconservative design for HSS-UHPC composite structures. In this study, the push-out tests of HSS-UHPC PBLs with varying plate thickness and strength were performed. The fracture of perfobond plates, the fracture of perforated rebars accompanied by the yielding of hole walls, and the rebar fracture without hole wall yielding were found as the three failure modes. The failure mode significantly affected the shear strength and slip capacity, and the shear stiffness increased with the plate thickness. Then, the FE models that considered the fracture of perfobond plates and perforated rebars were established and validated. 90 numerical models with different hole diameters, plate thicknesses, and steel grades were built to investigate the transition conditions between the failure modes. Lastly, a shear capacity equation for PBLs considering the varying failure modes was proposed, which matched well with the parametric study results. [ABSTRACT FROM AUTHOR]

2D Boron is an atomically thin layer of boron with both light weight and metallicity, two kinds of potential structures are proposed, namely, a close-packed triangular B layer(denoted B △ hereafter) and a hexagonal voids or vacancies ( Image 2 ) in B layer(denoted Image 4 hereafter) (Evgeni S. et al. Nano Lett. 2012, 12, 2441–2445). Here, we use first-principles calculations to investigate the potential of borophene as an anode material for sodium-ion batteries. It is found that borophene has an adsorption energy to sodium atoms of −1.448 eV for all boron atoms in the plane ( Image 3 ) and −1.731 eV for B Δ . The fully sodiated phase of borophene is Na 0.083 B and Na 0.1 B for B Δ and Image 3 , respectively, which corresponds to a theoretical specific capacity of 248 mAh g −1 (496 mAh g −1 for two sides) for B Δ and 298 mAh g −1 (596 mAh g −1 for two sides) for Image 3 . The energy barrier along the furrow of corrugated borophene is only 12 meV for B Δ , which suggests that sodium diffusion on borophene can be extremely fast for B Δ . In addition, a strong directional anisotropy is observed for sodium diffusion with a 352.5 meV barrier perpendicular to the furrow of B Δ . Finally, both exhibit metallic characteristics during the entire sodiation process, which indicates that the material has excellent electronic conductivity. The findings in this work suggest that as an anode material for sodium-ion batteries, borophene can drastically boost the energy and power density of batteries. [ABSTRACT FROM AUTHOR]

• The static and dynamic mechanical properties test of steel fiber reinforced concrete is carried out. • The influence law and mechanism of steel fiber and strain rate on dynamic mechanical properties of concrete are clarified. • The dynamic constitutive model of steel fiber reinforced concrete is proposed. This paper describes an investigation of the influence of steel fiber on the dynamic compressive behavior of steel fiber reinforced concrete (SFRC) at different strain rates, and reveals the mechanism of its change from the macro and meso levels. Meanwhile, a suitable dynamic constitutive model for SFRC is proposed. Four kinds of steel fiber contents (0 %, 1 %, 2 %, 3 %) and four kinds of high strain rates (40 s−1–220 s−1) were considered in the Split Hopkinson pressure bar (SHPB) test. Based on the designed tests, the failure pattern, the stress–strain curve, and the mechanical characteristic parameters of the SFRC under different loading conditions were obtained. The effects of steel fiber content and strain rate on the dynamic mechanical properties of concretes were analyzed. It is indicated that there are great differences in the failure pattern of the SFRC under different loading conditions. On the one hand, with the increase in the strain rate, the specimen is broken more completely. On the other hand, the reinforcing effect of steel fibers is obvious and as the steel fiber content increases, the crushing degree of the sample decreases significantly. The dynamic compressive strength of the SFRC is most sensitive to the strain rate and reaches its maximum value when the fiber content is 1 %. However, the variation of the peak strain showed no obvious regularity. The reinforcement mechanism of steel fibers was analyzed via the CT scanning technology. The results show that the main factors affecting the mechanical properties of SFRC are fiber content and porosity, but the fiber distribution is almost unaffected. The SFRC dynamic constitutive model was proposed by improving the HJC dynamic constitutive model. In the proposed model, the influence of steel fiber on strength was introduced and the influence term of strain rate was adjusted. The proposed model was verified by applying it to the numerical simulation of the dynamic compression performance of SFRCs and it shows good applicability. The presented research provides a theoretical basis for calculation and analysis of SFRC structures under extreme dynamic loads. [ABSTRACT FROM AUTHOR]