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Board informal hierarchy plays a crucial role in board governance and corporate strategic decision-making. The article empirically examines the impact of board informal hierarchy on corporate digital transformation based on relational contract theory, using a fixed-effects model with Shanghai and Shenzhen A-share listed manufacturing companies from 2012 to 2019 as research subjects. The findings of this study demonstrate a positive correlation between board informal hierarchy and digital transformation. Specifically, the presence of a chairman with the highest rank in the informal hierarchy strengthens this relationship, while the presence of a CEO with the highest rank weakens it. Mechanistic analysis shows that informal hierarchy accelerates digital transformation through three channels: improving board decision-making efficiency, mitigating management myopia, and facilitating information communication. This study extends existing research. On the one hand, this paper explores the drivers of digital transformation in manufacturing firms at the level of corporate governance and board characteristics. The findings provide empirical evidence to support the understanding of transformational change behaviors of manufacturing enterprises in the digital economy. On the other hand, it also opens up the "black box" of the internal operation of the board and provides valuable lessons for strengthening board governance. JEL Classification: D21; M12; Z13. Plain Language Summary: Board Informal Hierarchy and Digital Transformation The article empirically examines the impact of board informal hierarchy on corporate digital transformation based on relational contract theory, using a fixed-effects model with Shanghai and Shenzhen A-share listed manufacturing companies from 2012 to 2019 as research subjects. The findings of this study demonstrate a positive correlation between board informal hierarchy and digital transformation. Specifically, the presence of a chairman with the highest rank in the informal hierarchy strengthens this relationship, while the presence of a CEO with the highest rank weakens it. Mechanistic analysis shows that informal hierarchy accelerates digital transformation through three channels: improving board decision-making efficiency, mitigating management myopia, and facilitating information communication. This study extends existing research. On the one hand, this paper explores the drivers of digital transformation in manufacturing firms at the level of corporate governance and board characteristics. The findings provide empirical evidence to support the understanding of transformational change behaviors of manufacturing enterprises in the digital economy. On the other hand, it also opens up the "black box" of the internal operation of the board and provides valuable lessons for strengthening board governance. [ABSTRACT FROM AUTHOR]

Atherosclerotic plaque formation is characterized by the persistence of lipid-laden macrophages on the inner walls of arteries. Chronic inflammation and imbalanced macrophage function are likely to play a critical role. Herein, we investigated whether bromodomain-containing protein 7 (Brd7), a member of the bromodomain-containing protein family, regulates atherosclerosis, and if so, which mechanisms are responsible for the process. We found that Brd7 is expressed in mouse atherosclerotic plaques, and mostly in macrophages. Inhibition of Brd7 accelerates atherosclerotic lesion formation in ApoE −/− mice by promoting NF-κB–mediated inflammation. Furthermore, Brd7 inhibition alters the phenotype of macrophages and promotes plaque instability, at least partly via STAT6 signaling. Our data define a previously undescribed role of Brd7 in the development of atherosclerosis. [ABSTRACT FROM AUTHOR]

Abstract: Uniform Fe3O4 nanowires could be synthesized via a NaAc-assisted coprecipitation method. The diameter and length of as-prepared nanowires are ~30nm and ~500nm, respectively. The morphology and diameter of the products can be tuned by altering the reaction conditions. The magnetic and microwave absorption properties of Fe3O4 nanowires and nanosheets were also investigated in detail. Magnetic studies revealed that the saturation magnetization (Ms=68.21emu/g) of Fe3O4 nanowires lower than that of the sheet-like ones (96.45emu/g). Electromagnetic and resulting microwave adsorption properties showed the maximum magnitude for Fe3O4 nanowires is −16.67dB at 8.32GHz, which is superiority to that of sheet-like ones (−8.89dB at 10.24GHz). [Copyright &y& Elsevier]

Abstract: Size-controlled Fe3O4 nanoparticles were prepared via a facile solvothermal method by using the mixed surfactants of SDS and PEG as protective reagents. The sizes of the nanoparticles can be varied from 15 to 190nm by adjusting the experimental conditions. The influences of the protective reagents, reaction time, the initial concentration of the reactant, molar ratio of FeCl3 and protective reagents on the size of the produced nanoparticles were studied. The size and morphology of the products were investigated in detail by X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and scanning electron microscopy (SEM). [Copyright &y& Elsevier]

Abstract: Monodisperse Zn ferrite nanospheres and its Ba substitution nanosheets were successfully prepared by a facile solvothermal method. The size, morphology, and structure of the as-prepared products were investigated in detail by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), and inductively coupled plasma atomic emission spectroscopy (ICP-AES). Magnetic studies revealed that Zn ferrite nanospheres are ferrimagnetic with a saturation magnetization of 49.6 emu /g and increased from 49.6 emu /g to 84.2 emu /g when Ba2+ was substituted into Zn ferrite to form BaZn ferrite nanosheets. To explain the variations of morphology and magnetic properties, the strong preferential occupancy of cations in chemically equivalent A and B sites and the metastable cation distribution in nanoparticles are invoked. [Copyright &y& Elsevier]

Abstract: Round-biscuit-like Fe3O4 nanoparticles were successfully prepared in large-scale by a simple solvothermal method. The sizes of the particles can be readily tuned from 15 to 150 nm by adjusting the experimental parameters such as solvothermal temperature, reaction time, the initial concentration of the reactants, and molar ratio of FeCl3 and protective reagents. Structure, morphology and size products were investigated in detail by X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and scanning electron microscopy (SEM). Magnetic studies revealed that the saturation magnetization increases as the particle size increases. [Copyright &y& Elsevier]

BiVO 4 /CdS composites with different morphologies and mass ratios were successfully prepared via a facile deposition-precipitation method by adding different dispersants. Compared with spherical BiVO 4 (BS), sheet-like BiVO 4 nanoarrays (BA) showed higher (020) exposed areas, as confirmed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). X-ray photoelectron spectroscopy (XPS) revealed further details on the microstructure of the composites namely, CdS was deposited on the surface of BiVO 4 forming an S-(111) interface layer. The photocatalytic properties of the samples were tested by studying the degradation of Rhodamine B (RhB) and the sterilization of Escherichia coli (E. coli) under visible-light irradiation. The BAC-60 sample showed the best photocatalytic performance among all the catalysts owing to its: (i) improved high separation efficiency of the photo-induced charge carriers and (ii) high exposure activity of the (020) plane. Electrochemical tests with non-equilibrium carrier injection and free radical trapping experiments are introduced to analyze the mechanism, such as the effects of different crystal planes on the photocatalytic reaction and the flow direction of carriers at the CdS–BiVO 4 interface. • BiVO 4 /CdS composites are successfully prepared by depositing CdS on the surface of BiVO 4 with S-(111) layer as interface. • (020) plane of BiVO 4 is more photocatalytically active. • The initial inactivation of E. coli is due to the decomposition of bacterial proteins with a mass range m/z of 2 - 6 kDa. • The injection of non-equilibrium carrier results in the reversal of the interface current of BiVO 4 /CdS. [ABSTRACT FROM AUTHOR]

• The end-restraint effect in composite beam with URSP connectors is proposed for the first time, and the mechanism of force transfer of URSP composite beams is revealed. • The actual performance of the new type of connectors is investigated using beam tests. • Successfully verified the effectiveness of URSP technology for crack resistance in the negative moment zone of the composite beam. • The key mechanical properties of composite beam with URSP connectors are discussed in depth. The uplift-restricted and slip-permitted (URSP) connector technology is a new composite technology which achieves the purpose of reducing the tensile stress in concrete slab by releasing part of the composite action in the negative moment region. In this paper, it is found that arranging URSP connectors in continuous composite beams has an end-restraint effect, which has a significant impact on the force transfer mechanism of URSP composite beams. Previous studies on URSP technology seldom mention similar constraint effects, which cannot accurately reveal the mechanical behavior of URSP composite beams. In order to properly consider the influence brought by the end-restraint effect, this study uses continuous composite beams to carry out experimental research. Three two-span continuous composite specimens are fabricated and tested in this research. Six aspects of performance are compared and analyzed in detail, including ① cracking load, ② crack distribution and development pattern, ③ interfacial slip behavior, ④ deformation and stiffness, ⑤ internal force redistribution, and ⑥ strain distribution. It is found that the URSP connector can realize the release of part of the composite action, and has a significant effect on the crack control in the negative moment region. Meanwhile, the application of URSP connectors has little effect on the stiffness, bearing capacity and strain of steel beam. [ABSTRACT FROM AUTHOR]

Substructuring approaches possess many superiorities over traditional global approaches in damage identification because large-size global structures are replaced by small and manageable substructures. This paper proposes a substructural time series model for locating and quantifying the damage in complex systems. A substructural autoregressive moving average with exogenous inputs (ARMAX) model is established to extract the frequencies and mode shapes of substructures as indicators for damage detection. The detection of structural damage is essentially an inverse problem, and the damage in structure bears sparse properties. The inverse problem of substructural damage identification is efficiently solved via sparse regularization, and structural damage can be located and quantified through the nonzero terms in the solution vector. The accuracy of the proposed method is demonstrated by the numerical simulation of a frame structure and shaking table test of a shear building structure. As the substructural properties are more sensitive to local structural damage than the global properties, the substructural ARMAX model is quite accurate and efficient to be used in the damage identification of a complex system. [ABSTRACT FROM AUTHOR]

This paper reports the wind tunnel study of the vortex-induced vibration (VIV) of a free-standing steel arch bridge tower with pentagon cross-section. The tests were carried out at different yaw angles β (0°–90°) of wind flow by employing a 1:50 scaled aeroelastic model. A series of aerodynamic measures were studied to mitigate the VIV of the tower at the most unfavorable yaw angle. Effects of turbulence intensity and structural damping on the VIV performance of the tower were evaluated. A sleeve-type eddy current damper (ECD) for increasing the structural damping of aeroelastic model was designed for reserved emergency measures. Experimental results indicate that the VIV occurs for a few yaw angles at wind velocity of 15–18 m/s and the maximum VIV amplitude happens for β = 35°. The aerodynamic measures are effective for some yaw angles but become invalid for other yaw angles. Compared to those in smooth flow, the VIV amplitude drops by 65% for a turbulence intensity of 8.5%. The VIV of the tower can be effectively suppressed by the eddy current damper which provides additional damping to the aeroelastic model. The sleeve-type eddy current damper is shown to be a convenient device to adjust the damping for aeroelastic models. • VIV of the steel arch tower occurs for the fundamental longitudinal mode. • The obvious VIV mitigation effects were observed installing several aerodynamic measures in the 35° yaw angle. • The proposed sleeve-type eddy current damper is able to provide additional damping in the aeroelastic model. [ABSTRACT FROM AUTHOR]

In this study, aerodynamic interference effects (AIE) on the vibration response, aerostatic coefficient (AC) and vortex-induced vibration (VIV) mechanism of the triple-separated decks under different incoming wind directions and vertical distances were investigated via wind tunnel tests and numerical simulations, respectively. The test results show that the AIE increases the displacement of VIV, and the VIV responses reaches maximum value under S/H = −1.0 (S is the vertical distance between the centers of RB and HB decks, and H is the height of RB deck) when the RB deck is on the windward side (the maximum displacements of VIV are 193.86% and 37.30% higher than the case of single RB deck and S/H = 0.0, respectively). The pressure distribution and flow structure show that the scale of vortex that alternately shed off from the tail of the deck becomes stronger and the fluctuating pressure coefficient increases under AIE, which increase the VIV amplitude of the RB deck and cause the VIV of HB decks. The experimental and numerical results indicated that the aerostatic coefficients (AC) of the leeward girder are more affected by the AIE. The interference factor (IF) of drag coefficient (C D) is far less than 1.0 under the case of F-5 (S/H = 0.0). • The aerodynamic interference effects (AIE) on the vibration responses and aerostatic coefficients of two parallel bridge with triple-separated decks are investigated by wind tunnel tests and numerical simulations. • The effects of incoming wind direction and vertical distance on AIE are considered. • The vortex-induced vibration (VIV) mechanism under AIE is analyzed by the pressure distribution and the static flow structure. [ABSTRACT FROM AUTHOR]

Single-phase silver antimonite have quite low oxidation and reduction potential because of the easy recombination of photogenerated electrons and holes. In the study, a novel ternary graphene@Ag/AgSb2O5.8 (G @Ag/ASO) visible-light-driven photocatalyst was successfully synthesized by a simple hydrothermal method. The morphology, structure, and chemical composition of G @Ag/ASO and its sinters at different temperatures in the air atmosphere were systematically characterized by a range of techniques. Reaction laws of the composites in the sintering process have been revealed based on the Ellingham diagram. The photocatalytic degradation of rhodamine B (RhB) dye and tetracycline hydrochloride (OTC-HCl) by the as-synthesized photocatalyst was investigated under visible light irradiation. The G@Ag/ASO-500 (the sinter at 500°C) exhibits degradation efficiency of 80% for RhB and 85% for OTC-HCl in 120 min, higher than those for AgSb2O5.8 (20% and 24%, respectively). The graphene-enhanced Ag-loaded AgSb2O5.8 model is proposed and reasonably accounts for the high-efficiency electron-hole transfer mechanism through four contact potentials and the crucial role of graphene sheets on the surface of the composites. The present study provides a new perspective for enhancing photocatalytic performance. [ABSTRACT FROM AUTHOR]

Abstract: We demonstrated that ZnFe2O4/polypyrrole core-shell nanoparticles could be facilely synthesized via in situ chemical oxidative polymerization of pyrrole monomers on the surface of ZnFe2O4 nanoparticles. The shell thickness of core-shell nanoparticles could be easily controlled by adjusting the amount of pyrrole monomers. The phase structures, morphologies and properties of the as-prepared products were investigated by XRD, TEM, SEM, VSM, and FTIR spectra. Magnetic studies revealed that the saturation magnetization (M s) and coercivity (H c) of ZnFe2O4/PPy core-shell nanoparticles is 17.8emu/g and 130Oe, respectively. The electromagnetic characteristics of products showed that ZnFe2O4/PPy core-shell nanoparticles exhibit excellent microwave absorption performance than ZnFe2O4 nanoparticles, such as more powerful absorbing property and wider electromagnetic wave absorbing frequency band due to the proper matching of the permittivity and the permeability of ZnFe2O4/PPy core-shell nanoparticles. [Copyright &y& Elsevier]

Abstract: Inorganic nanoparticles with controlled size and shape are technologically important due to the strong correlation between these parameters and magnetic, electrical, and catalytic properties. Herein we demonstrated that under appropriate conditions, rodlike α-FeOOH (goethite) and porous fusiform α-Fe2O3 (hematite) uniform nanocrystallines could be selectively synthesized in large quantities via a facile surfactant sodium dodecyl sulfate (SDS) assisted hydrothermal synthetic route. The morphology and structure of the final products were investigated in detail by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and selected area electron diffraction (SAED). The probable formation mechanism of the α-FeOOH and α-Fe2O3 uniform nanoparticles was discussed on the basis of the experimental results. [Copyright &y& Elsevier]

The visible-light-responsive composite photocatalyst is beneficial to improve the solar energy utilization efficiency through the coupling of narrow bandgap materials. In this work, CdS nanowires were prepared by hydrothermal method, and then BiOBr/CdS composite materials with different mass ratios were successfully prepared by a simple two-step sonography-precipitation method using CdS nanowires as a deposition template. The photocatalysts were characterized by XRD, SEM, XPS, TEM, and other methods. Rhodamine B (RhB) was used as a model pollutant to evaluate the photocatalytic activity of BiOBr/CdS catalysts with different mass ratios. The photocatalytic test results show that the composite photocatalyst containing 60% BiOBr has the highest photocatalytic activity, which indicates that it is related to the decrease in photogenerated charge recombination rate. Subsequently, the electrochemical and physical methods were used to illustrate the electron transfer mechanism and the main active center of the as-prepared samples. Free radical capture experiments reveal that holes are the main active species in the photocatalytic process of composite samples. BiOBr/CdS composite photocatalyst was prepared by a simple precipitation method using dispersed one-dimensional CdS nanowires as a template. BiOBr/CdS heterostructure combined adsorption and catalysis to degrade RhB molecules more efficiently. Free radical trapping experiments reveal that holes are the main active species in the photocatalytic process of composite samples. [ABSTRACT FROM AUTHOR]

Ag/Ag1.69Sb2.27O6.25 sesame-hollow-ball-type nanocomposites were prepared via a facile one-step hydrothermal method at 400 K. Power X-ray diffraction analysis shows that all diffraction peaks were well consistent with JCPDS card no: 89-6552 of Ag1.69Sb2.27O6.25. Scanning electron microscopy and high-resolution transmission electron microscopy images of the composites indicate that some smaller metallic Ag particles with size∼18.3 nm uniformly dense on the surface of Ag1.69Sb2.27O6.25 hollow nanospheres with a mean size of about 170 nm, producing Ag/Ag1.69Sb2.27O6.25 hollow-sesame-ball nanocomposites. The surface chemical state of Ag/Ag1.69Sb2.27O6.25 is investigated by XPS, and all peaks of Ag 3d, O 1s, and Sb 3d show their different chemical states. The BET surface area of the sample is 7.268 m2/g, and the pore sizes of nanocomposites are more than 5 nm. The light absorption property of as-prepared materials is studied by UV-vis/DRS, and the adsorption band is located at 445 nm, and the estimated energy band gap (Eg) is 2.55 eV. The calculated partial φ-pH diagrams in the Ag-H2O system at 400 K predict that the Ag+ ion can react with H2 to form metallic Ag. [ABSTRACT FROM AUTHOR]

The metastable α-Ag 2 MoO 4 was usually prepared under high pressure conditions, but it was successfully prepared by epitaxial growth on WO 3 nanosheets at room temperature under normal pressure in this work. The interfacial structure of α-Ag 2 MoO 4 /WO 3 (AW) was characterized by XRD, SEM, TEM, and Raman spectra to explain the process of phase transformation from the β phase to the α phase. The photocatalytic activities were evaluated by the degradation of methylene blue and Escherichia coli. The results indicate that AW-60 exhibits the best photocatalytic activity. The enhancement in photocatalytic performance is mainly due to the photogenerated electron flow between the components from WO 3 to Ag 2 MoO 4 in AW-60. The initial inactivation of E. coli is due to the decomposition of macromolecules with a typical mass range m / z of 2–7 kDa. The corresponding photocatalytic mechanism was proposed and confirmed by the measurements, such as BET, fluorescence spectrum, free radical trapping and the ζ potential of WO 3 and AW-60. • α-Ag2MoO4 was successfully prepared by epitaxial growth on the {100} plane family of WO3. • Under normal pressure due to lattice matching. • The sample with WO3/α-Ag2MoO4 mass ratio of 2:3 exhibited the best visible light-driven. • Photocatalytic activity. • The electron transfer mechanism in α-Ag2MoO4/WO3 was discussed. [ABSTRACT FROM AUTHOR]

Abstract: Size-controlled nickel ferrite nanoparticles could be successfully synthesized via a simple solvothermal method by using ethylene glycol as solvent and NaAc as electrostatic stabilization. The size of the nanoparticles can be easily controlled from 6 to 170nm by adjusting the experimental parameters such as reaction duration, initial concentration of the reactants, amount of protective reagents, and the type of acetates. The structure, size, morphology, and property of final products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and vibrating sample magnetometer (VSM). The investigation on magnetic properties of nickel ferrite nanoparticles indicates that coercivity and magnetization values are directly influenced by the size of final products. [Copyright &y& Elsevier]

Abstract: Sea urchin-like nanorod-based nickel and cobalt selenides nanocrystals have been selective synthesized via a hydrothermal reduction route in which hydrated nickel chloride and hydrated cobalt chloride were employed to supply Ni and Co source and aqueous hydrazine (N2H4·H2O) was used as reducing agent. The composition, morphology, and structure of final products could be easily controlled by adjusting the molar ratios of reactants and process parameters such as hydrothermal time. The morphology and phase structure of the final products have been investigated by X-ray diffraction, transmission electron microscopy, and scanning electron microscopy. The probable formation mechanism of the sea urchin-like nanorod-based nickel and cobalt selenides nanocrystals was discussed on the basis of the experimental results. [Copyright &y& Elsevier]

As an effective method to solve the environmental crisis and energy reserve problems, visible light-driven photocatalysts have attracted widespread attention. Various semiconductor materials (such as WO 3 , CdS, g-C 3 N 4 , Ag 3 PO 4 and BiVO 4) have been used as photocatalysts. Therefore, in this work, CdS/C 3 N 4 composite photocatalysts were prepared by simple co-precipitation method to improve the performance of CdS, and Rhodamine B (RhB) was used to evaluate the photocatalytic activity. The results show that the composite photocatalyst containing 20% CdS has the highest photocatalytic activity. In addition, the effects of different temperatures on the properties of the samples were investigated by heat treatment. It shows that the properties of 20% CdS/C 3 N 4 (CS-20) are greatly improved after heat treatment, due to the multiphase structure. CS-x series compounds were successfully prepared by depositing CdS nanoparticles on the surface of C 3 N 4 nanosheets, CS-20 having the highest photocatalytic activity. Heat treatment significantly affects the activity of composite samples with a 30% performance improvement, 300 °C being the optimal temperature. [Display omitted] • CS-x series compounds were successfully prepared by depositing CdS nanoparticles on the surface of C 3 N 4 nanosheets. • The Z-scheme mechanism is comfirmed for the photocatalytic process over the C 3 N 4 -CdS system. • The change of interface structure leads to the improvement of photocatalytic performance through heat treatment. [ABSTRACT FROM AUTHOR]