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Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A highly stable and overall water splitting electrocatalyst (NF/FeNiP-CoP@NC) featuring porous configuration, numerous heterogeneous interfaces, obvious vacancies and doping defects, and abundant active species in a hierarchical heterostructure is reported, which is fabricated by a hydrothermal reaction-ion exchange-phosphorization technique. [Display omitted] • Hollow porous cubic FeNiP-CoP@NC loaded on nickel foam is prepared. • The NF/FeNiP-CoP@NC inherits excellent OER, HER, and OWS performance. • DFT confirms that the unique structure promotes the overall OWS performance. Multimetal phosphides derived from metal-organic frameworks (MOFs) have garnered significant interest owing to their distinct electronic configurations and abundant active sites. However, developing robust and efficient catalysts based on metal phosphides for overall water splitting (OWS) remains challenging. Herein, we present an approach for synthesizing a self-supporting hollow porous cubic FeNiP-CoP@NC catalyst on a nickel foam (NF) substrate. Through ion exchange, the reconstruction chemistry transforms the FeNi-MOF nanospheres into intricate hollow porous FeNi-MOF-Co nanocubes. After phosphorization, numerous N, P co-doped carbon-coated FeNiP-CoP nanoparticles were tightly embedded within a two-dimensional (2D) carbon matrix. The NF/FeNiP-CoP@NC heterostructure retained a porous configuration, numerous heterogeneous interfaces, distinct defects, and a rich composition of active sites. Moreover, incorporating Co and the resulting structural evolution facilitated the electron transfer in FeNiP-CoP@NC, enhancing the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) processes. Consequently, the NF/FeNiP-CoP@NC catalyst demonstrated very low overpotentials of 78 mV for OER and 254 mV for HER in an alkaline medium. It also exhibited excellent long-term stability at various potentials (@10 mA cm−2, @20 mA cm−2, and @50 mA cm−2). As an overall water splitting cell, it required only 1.478 V to drive a current density of 50 mA cm−2 and demonstrated long-term stability. Density functional theory (DFT) calculations revealed a synergistic effect between multimetal phosphides, enhancing the intrinsic OER and HER activities of FeNiP-CoP@NC. This work not only elucidates the role of heteroatom induction in structural reconstruction but also highlights the importance of electronic structure modulation. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Managing the level-of-detail (LOD) in architectural models is crucial yet challenging, particularly for effective representation and visualization of buildings. Traditional approaches often fail to deliver controllable detail alongside semantic consistency, especially when dealing with noisy and inconsistent inputs. We address these limitations with Co-LOD, a new approach specifically designed for effective LOD management in architectural modeling. Co-LOD employs shape co-analysis to standardize geometric structures across multiple buildings, facilitating the progressive and consistent generation of LODs. This method allows for precise detailing in both individual models and model collections, ensuring semantic integrity. Extensive experiments demonstrate that Co-LOD effectively applies accurate LOD across a variety of architectural inputs, consistently delivering superior detail and quality in LOD representations. [ABSTRACT FROM AUTHOR]

Metal‐organic hybrid catalysts with highly tunable single‐sites are promising for oxygen‐evolution reaction (OER), but molecular‐scale understanding of underlying reaction mechanisms still remain elusive on these bulk materials. Herein, we report a direct construction of heterogenized molecular complexes stabilized on carbon substrates via coordinating Fe−Ni sites with four aromatic carboxylate ligands (FeNi‐Lx). The ligands‐tuning π‐π stacking interaction between aromatic carboxylate ligands and carbon supports promote the oxidative charge accumulation on Fe−Ni sites via fast electron transferring, thus the optimized FeNi‐Lx rendering a mass activity of 6680 A gFe/Ni−1 at 0.3 V overpotential. In situ characteristics and theoretical analysis demonstrate that the OH− nucleophilic attack on hypervalent iron sites induce the reconstruction of active Fe−O−Ni species, accompanying with fast valence increasing. Whereas, during OER, the unexpected valence reduction of Fe−O−Ni sites would be attributed to the oxygen‐generating from OOH* intermediates. These findings would establish an essential understanding of the origin of active centers in molecular complexes catalysts for oxygen‐evolution. [ABSTRACT FROM AUTHOR]

Transition metal sulfides, particularly heterostructures, represent a promising class of electrocatalysts for two electron oxygen reduction (2e− ORR), however, understanding the dynamic structural evolution of these catalysts during alkaline ORR remains relatively unexplored. Herein, NiS2/In2.77S4 heterostructure was synthesized as a precatalyst and through a series of comprehensive ex situ and in situ characterizations, including X‐ray absorption spectroscopy, Raman spectroscopy, transient photo‐induced voltage measurements, electron energy loss spectroscopy, and spherical aberration‐corrected electron microscopy, it was revealed that nickel/indium (oxy)hydroxides (NiOOH/In(OH)3) could be evolved from the initial NiS2/In2.77S4 via both electrochemical and chemical‐driven methods. The electrochemical‐driven phase featured abundant bridging oxygen‐deficient [NiO6]‐[InO6] units at the interfaces of NiOOH/In(OH)3, facilitating a synergistic effect between active Ni and In sites, thus enabling an enhanced alkaline 2e− ORR capability than that of chemical‐driven process. Remarkably, electrochemically induced NiOOH/In(OH)3 exhibited exceptional performance, achieving H2O2 selectivity of >90 % across the wide potential window (up to 0.4 V) with a peak selectivity of >99 %. Notably, within the three‐electrode flow cell, a current density of 200 mA cm−2 was sustained over 20 h, together with an impressive Faradaic efficiency of ~90 % during the whole cycle process. [ABSTRACT FROM AUTHOR]

Metal‐organic frameworks (MOFs) have emerged as promising pre‐catalysts for oxygen evolution reaction (OER) due to their marvelous structural reconstruction process in strongly alkaline media. However, targeting design MOF structures to achieve excellent OER performance of reconstructed products is a challenge. Here, a strategic defect engineering is used to promote the OER performance of reconstructed products. Briefly, modified linkers with monocarboxylic acids (ferrocene carboxylic acid, FcCA) are incorporated into MOF (NiBDC‐FcCA), leading to its stepwise reconstruction into Fe‐doped Ni(OH)2 and NiOOH during the OER process, with the oxygen vacancy and strategic doping of metal Fe persisting throughout the multi‐step reconstruction. Benefiting from the synergistic interaction of oxygen vacancies and Fe doping, NiBDC‐FcCA delivers the extremely enhanced current density at 1.6 V versus reversible hydrogen electrode by ≈9 times compared with that of NiBDC. Moreover, the optimized NiBDC‐FcCA/Fe foam exhibits excellent OER catalytic activity and stability with a low overpotential of 250 mV at 200 mA cm−2 and negligible activity decay after 1200 h at 1 A cm−2. Density function theory calculations reveal that Fe doping weakens the interaction of oxygen intermediate with Ni sites, favoring the formation of OOH* to accelerate the OER process. [ABSTRACT FROM AUTHOR]

The inefficiency of electrocatalysts for water splitting in neutral media stems from a comprehensive impact of poor intrinsic activity, a limited number of active sites, and inadequate mass transport. Herein, hierarchical ultrathin NiCo2Se4 nanosheets are synthesized by the selenization of NiCo2O4 porous nanoneedles. Theoretical and experimental investigations reveal that the intrinsic hydrogen evolution reaction (HER) activity primarily originate from the NiCo2Se4, whereas the high oxygen evolution reaction (OER) performance is related to the NiCoOOH due to the structural reconstruction. The abundant Se and O vacancies introduced by atomically thin nanostructure modulate the electronic structure of NiCo2Se4 and NiCoOOH, thereby improving the intrinsic HER and OER activities, respectively. COMSOL simulation demonstrate the edges of extended nanosheets from the main body significantly promote the charge aggregation, boosting the reduction and oxidation current during HER/OER process. This charge aggregation effect notably exceeds the tip effect for the nanoneedle, highlighting the unique advantage of the hierarchical nanosheet structure. Benefiting from abundant vacancies and unique nanostructure, the hierarchical ultrathin nanosheet simultaneously improve the thermodynamics and kinetics of the electrocatalyst. The optimized samples display an overpotential of 92 mV for HER and 214 mV for OER at 100 mA cm−2, significantly surpassing the performance of currently reported HER/OER catalysts in neutral media. [ABSTRACT FROM AUTHOR]

In response to the challenges of numerous knowledge points and fragmented concepts in the structural chemistry course, as well as the difficulty for students to establish a disciplinary framework and a comprehensive knowledge system, this paper proposed a logical framework and knowledge graph, based on the thematic thread of "Schrödinger equation approximation models - core concepts - simple applications". This framework includes six branches: particle in box model, single electron hydrogen-like atoms, multi-electron atoms, H2 + molecular, H2 molecules, and multi-atom molecules. By reconstructing fragmented knowledge and forming a complete knowledge chain, this approach aims to help students understand the logical relationships, generation context and interconnections of important concepts, and provides them with a context for knowledge transfer, ultimately facilitating their understanding and application of knowledge. [ABSTRACT FROM AUTHOR]

Highlights Co and Cl co-doped NiS is an efficient bifunctional electrocatalyst for converting plastic waste into formate and hydrogen with high efficiency and selectivity Dopants regulate the electronic property and accelerate structural reconstruction of NiS for the core ethylene glycol (PET monomer) oxidation reaction PET hydrolysate electrolysis can produce hydrogen gas at an average rate of 50.26 mmol h−1 at 1.7 V

Based on the field observations and tectono-sedimentary analysis, we suggest reconstruction of the geological evolution from case study of Northern Tunisia since the Eocene age. The reconstruction of the structural architecture of this region can be aided by knowing the spatiotemporal occurrence and the deformation of the Oligo‒Early Miocene deposits. In the research area, two depositional basin types that coexisted but in different tectonic settings were seen in the reconstruction of Oligo‒Early Miocene successions. In Northern Tunisia, the Late Eocene shortening episode led to a thin-skinned deformation that produced irregular basement topography. During the Oligo‒Early Miocene subduction process, the earliest lithofacies of the Maghrebian Numidian flysch deposited in deep marine offshore environment. Synchronously in the onshore, the second lithofacies of Fortuna were deposited in NW-trending extensional structures after a rifting episode that characterized north-eastern Tunisia (ante-nappes). During the Middle Miocene, the curving fore-arc of subduction between Africa and the Mesomediterranean Microplate dominated northern Tunisia. As a result, the Numidian basin was raised, resulting in thrust sheets in northwestern part of Tunisia, while the extensional structures supporting the Fortuna succession were closed and created push-up structures following transpressional deformation along the NW‒SE boundary faults. Continental collision has occurred in northern Tunisia since the Late Miocene, resulting in shortening structures, some elevated areas, and sedimentary gaps encompassing a substantial portion of the study area. [ABSTRACT FROM AUTHOR]

In recent years, the research and development of high-speed trains has advanced rapidly. The main development trends of high-speed trains are higher speeds, lower energy consumption, higher safety, and better environmental protection. The realization of a lightweight high-speed car body is one of the key features in the development trend of high-speed trains. Firstly, the basic dimensions of the car body's geometric model are determined according to the external dimensions of the body of a CRH EMU, and the specific topology optimization design domain is selected to establish the finite element analysis model; secondly, the strength and modal analyses of the topology optimization design domain are carried out to check the accuracy of the design domain and provide a comparative analysis for subsequent design. Then, the variables, constraints, and objective functions of the topology optimization design are determined to establish the mathematical model of topology optimization, and the design domain is calculated for topology optimization under single and multiple conditions, respectively. Finally, based on the topology optimization calculation results, truss-type reconstruction modeling is carried out for the car body's side walls, roof, underframe, end walls, and other parts. Compared with the conventional EMU body structure, the weight of the reconstructed body structure is reduced by about 18%. The results of the finite element analysis of the reconstructed car-body structure prove the reliability and safety of the structure, indicating that the reconstructed car-body scheme meets the corresponding performance indicators. [ABSTRACT FROM AUTHOR]

Electrocatalytic biomass valorization coupled with hydrogen production provides an efficient and economical way to achieve a zero‐carbon economy. Ni‐based electrocatalysts are promising candidates due to their intrinsic redox capabilities, but the rational design of active Ni site coordination is still a huge challenge. Herein, the combined strategies of surface reconstruction and heteroatom doping are adopted to modify Ni3S2 pre‐catalysts and the obtained bimetallic catalyst exhibits superior electrocatalytic performance toward 5‐hydroxymethylfurfural (HMF) oxidation to 2,5‐furanedicarboxylic acid (FDCA). Specifically, the oxysulfide‐coordinated amorphous NiOOH (NiOOH‐SOx) active phase is in situ constructed following the anionic regulation mechanism, which endows numerous defects and unsaturated sites for anodic HMF oxidation. Cu heteroatom doping further modulates the electronic structure of active sites with abundant Lewis acidic sites, offering advanced capability for HMF adsorption. Several operando characterization techniques (in situ Raman, infrared, and electrochemical impedance spectroscopies) are performed to disclose the reaction pathway and structure‐activity‐potential relationship. Theoretical results further demonstrate that Cu doping and oxyanionic regulation effectively modulate the local coordination environment of Ni sites and correspondingly tailor the intermediate adsorption behavior and then promote the reaction kinetics. Moreover, a two‐electrode system is assembled to pair HMF oxidation with cathode hydrogen production, demonstrating better energy conversion efficiency. [ABSTRACT FROM AUTHOR]

Highlights A bimetallic lanthanum-nickel oxysulfide based on a La2O2S prototype was developed as a precatalyst for the electrochemical alkaline oxygen evolution reaction (OER). The in situ, ex situ, and theoretical investigations demonstrated that the precatalyst underwent a deep OER-driven reconstruction into a porous heterostructure where NiOOH nanodomains were uniformly separated and confined by La(OH)3 barrier. Oxyanion (SO4 2−) was steadily adsorbed on the surface of this in situ reconstructed NiOOH/La(OH)3 heterostructure, enabling it for enhanced OER activity and durability.

The anodic oxygen evolution reaction (OER) can be combined with various cathodic reactions to enable the electrochemical synthesis of diverse chemicals and fuels, particularly in water electrolysis for hydrogen production. It is however exhibiting a high overpotential due to the sluggish four-electron transfer process, which is considered the decisive reaction in energy conversion systems. In recent years, metal-organic frameworks (MOFs) have emerged as the ideal catalysts for accelerating OER. This is primarily because of their orderly porous architecture, structural tailorability, and compositional diversity. This review systematically summarizes the recent research progress in pristine MOF electrocatalysts for OER, which covers the construction strategies and electrocatalytic performance of more than eight types of MOFs. Additionally, the partial/complete structural reconstructions and their effects on MOF-based OER electrocatalysts are highlighted. In particular, the development process of "discovery, explanation, and utilization" for the structural reconstructions of MOF electrocatalysts is outlined. Furthermore, the catalytic mechanisms are elaborated in detail, aiming to provide insight into the rational design and performance optimization of MOF-based OER electrocatalysts. The challenges and future perspectives of MOF-based OER electrocatalysts for industrial applications are also discussed. [ABSTRACT FROM AUTHOR]

Quick‐charge technology is of great significance for the development of aqueous zinc‐ion batteries. In this study, an unreported in situ electrochemical amorphization mechanism is highlighted to unlock the ultrafast‐kinetics electrode. Multiple characterizations, density functional theory calculation, and molecular dynamic simulation are applied to uncover the storage mechanism of electrodes, as well as the evolution of structure, and reaction kinetics after reconstruction. As revealed, the long‐range ordered ZnV2O4 crystalline can be reconstructed to a short‐range ordered Zn0.44V2O4 electrode, which exhibits significantly improved active sites, shortened diffusion path, and enhanced zinc ions capture ability. Notably, by pairing with the modified Zn anode, it can display ultrahigh rate capability (212 mAh g−1 at 50 A g−1) with a maximum power density of 23.2 kW kg−1, as well as good cycle performance (217.2 mAh g−1 after 3000 cycles at 20 A g−1). Unexpectedly, such reconstructed amorphous electrodes can also retain superior storage capability even at cryogenic conditions. A high specific capacity of 251 mAh g−1 can be delivered at −25°C and 1 A g−1, as well as an 84.3% capacity retention after 500 cycles. This brand‐new in‐situ electrochemical amorphization mechanism is expected to provide new insight into understanding the high‐performance aqueous zinc‐ion batteries. [ABSTRACT FROM AUTHOR]

Highlights: Co and Cl co-doped NiS is an efficient bifunctional electrocatalyst for converting plastic waste into formate and hydrogen with high efficiency and selectivity Dopants regulate the electronic property and accelerate structural reconstruction of NiS for the core ethylene glycol (PET monomer) oxidation reaction PET hydrolysate electrolysis can produce hydrogen gas at an average rate of 50.26 mmol h−1 at 1.7 V Electro-upcycling of plastic waste into value-added chemicals/fuels is an attractive and sustainable way for plastic waste management. Recently, electrocatalytically converting polyethylene terephthalate (PET) into formate and hydrogen has aroused great interest, while developing low-cost catalysts with high efficiency and selectivity for the central ethylene glycol (PET monomer) oxidation reaction (EGOR) remains a challenge. Herein, a high-performance nickel sulfide catalyst for plastic waste electro-upcycling is designed by a cobalt and chloride co-doping strategy. Benefiting from the interconnected ultrathin nanosheet architecture, dual dopants induced up-shifting d band centre and facilitated in situ structural reconstruction, the Co and Cl co-doped Ni3S2 (Co, Cl-NiS) outperforms the single-doped and undoped analogues for EGOR. The self-evolved sulfide@oxyhydroxide heterostructure catalyzes EG-to-formate conversion with high Faradic efficiency (> 92%) and selectivity (> 91%) at high current densities (> 400 mA cm−2). Besides producing formate, the bifunctional Co, Cl-NiS-assisted PET hydrolysate electrolyzer can achieve a high hydrogen production rate of 50.26 mmol h−1 in 2 M KOH, at 1.7 V. This study not only demonstrates a dual-doping strategy to engineer cost-effective bifunctional catalysts for electrochemical conversion processes, but also provides a green and sustainable way for plastic waste upcycling and simultaneous energy-saving hydrogen production. [ABSTRACT FROM AUTHOR]

Transition metal‐based oxyhydroxides (MOOH) derived from the irreversible structural reconstruction of precatalysts are often acknowledged as the real catalytic species for the oxygen evolution reaction (OER). Typically, the reconstruction‐derived MOOH would exhibit superior OER activity compared to their directly synthesized counterparts, despite being fundamentally similar in chemistry. As such, structural reconstruction has emerged as a promising strategy to boost the catalytic activity of electrocatalysts. However, the in‐depth understanding of the origin of the superior OER activity of reconstructed materials still remains ambiguous, which significantly hinders the further developments of highly efficient electrocatalysts based on structural reconstruction chemistry. In this review, a comprehensive overview of the structural reconstruction behaviors in the reported reconstruction‐derived electrocatalysts is provided and the intrinsic chemical and structural origins of their high efficiency toward OER are unveiled. The fundamentals of structural reconstruction mechanisms, along with the recommended characterization techniques for the understanding of the dynamic structural reconstruction process and analyzing the structure of real catalytic species are also interpreted. Finally, in view of structural reconstruction chemistry, the potential perspectives to facilitate the design and synthesis of highly efficient and durable OER electrocatalyst are presented. [ABSTRACT FROM AUTHOR]

Highlights: A bimetallic lanthanum-nickel oxysulfide based on a La2O2S prototype was developed as a precatalyst for the electrochemical alkaline oxygen evolution reaction (OER). The in situ, ex situ, and theoretical investigations demonstrated that the precatalyst underwent a deep OER-driven reconstruction into a porous heterostructure where NiOOH nanodomains were uniformly separated and confined by La(OH)3 barrier. Oxyanion (SO42−) was steadily adsorbed on the surface of this in situ reconstructed NiOOH/La(OH)3 heterostructure, enabling it for enhanced OER activity and durability. Efficient and durable oxygen evolution reaction (OER) requires the electrocatalyst to bear abundant active sites, optimized electronic structure as well as robust component and mechanical stability. Herein, a bimetallic lanthanum-nickel oxysulfide with rich oxygen vacancies based on the La2O2S prototype is fabricated as a binder-free precatalyst for alkaline OER. The combination of advanced in situ and ex situ characterizations with theoretical calculation uncovers the synergistic effect among La, Ni, O, and S species during OER, which assures the adsorption and stabilization of the oxyanion SO 4 2 - onto the surface of the deeply reconstructed porous heterostructure composed of confining NiOOH nanodomains by La(OH)3 barrier. Such coupling, confinement, porosity and immobilization enable notable improvement in active site accessibility, phase stability, mass diffusion capability and the intrinsic Gibbs free energy of oxygen-containing intermediates. The optimized electrocatalyst delivers exceptional alkaline OER activity and durability, outperforming most of the Ni-based benchmark OER electrocatalysts. [ABSTRACT FROM AUTHOR]

Although α‐CsPbI3 is regarded as an attractive optical luminophore, it is readily degraded to the optically inactive δ‐phase under ambient conditions. Here, we present a simple approach to revive degraded ("optically sick") α‐CsPbI3 through "medication" with thiol‐containing ligands. The effect of different types of thiols is systematically studied through optical spectroscopy. The structural reconstruction of degraded α‐CsPbI3 nanocrystals to cubic crystals in the presence of thiol‐containing ligands is visualized through high‐resolution transmission electron microscopy and supported by X‐ray diffraction analysis. We found that 1‐dodecanethiol (DSH) effectively revives degraded CsPbI3 and results in high immunity towards moisture and oxygen, hitherto unreported. DSH facilitates the passivation of surface defects and etching of degraded Cs4PbI6 phase, thus reverting them back to the cubic CsPbI3 phase, leading to enhanced PL and environmental stability. [ABSTRACT FROM AUTHOR]

Electrochemical water splitting coupled with renewable energy offers a promising avenue for energy conversion and storage, but it is also extremely suppressed by the sluggish kinetics of oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). Herein, a multi‐layer architecture strategy was utilized by the in situ growth for cobalt phosphate of Hopeite‐like phase (Co‐H) on NiCo‐layered double hydroxide (NiCo‐LDH) to prepare a self‐supported electrode (Co‐H/NiCo@NF). The Co‐H formed over the NiCo‐LDH shows a unique sea urchin‐like morphology. The Co‐H/NiCo@NF displays excellent HER and OER activity, requiring only overpotentials of 180 mV and 350 mV to deliver 100 mA cm−2, consequently, be capable to generate an appealing cell potential of 1.76 V for overall water splitting at the corresponding current density. In addition, the prepared Co‐H/NiCo@NF has long‐term stability against 500 mA cm−2 and exhibits a trend of increased activity, which may associate with the structural reconstructions to form new phases and the strong bonding between layers. These findings demonstrate that the multi‐layer architecture with fine‐component modulation is a promising strategy for the development of robust and efficient cobalt phosphate electrocatalysts, and the role of multi‐layer in the evolution of structural reconstructions deserves further investigation. [ABSTRACT FROM AUTHOR]

The high-quality reutilization of waste styrene–butadiene–styrene copolymer (SBS) modified asphalt mixtures is a difficult issue in the field of highways today, and the main reason is that conventional rejuvenation technology fails to achieve the effective rejuvenation of aged SBS in binder, causing significant deterioration in the high-temperature performance of the rejuvenated mixture. In view of this, this study proposed a physicochemical rejuvenation process using a reactive single-component polyurethane (PU) prepolymer as the repairing substance for structural reconstruction and aromatic oil (AO) as a common rejuvenator used to supplement the lost light fractions of asphalt molecules in aged SBSmB, according to the characteristics of oxidative degradation products of SBS. The joint rejuvenation of aged SBS modified bitumen (aSBSmB) by PU and AO was investigated based on Fourier transform infrared Spectroscopy, Brookfield rotational viscosity, linear amplitude sweep, and dynamic shear rheometer tests. The results show that 3 wt% PU can completely react with the oxidation degradation products of SBS and rebuild its structure, while AO mainly acted as an inert component to increase the content of aromatic components, thereby reasonably adjusting the compatibility of chemical components of aSBSmB. Compared with the PU reaction-rejuvenated binder, the 3 wt% PU/10 wt% AO rejuvenated binder had a lower high-temperature viscosity for better workability. The chemical reaction between PU and SBS degradation products dominated in the high-temperature stability of rejuvenated SBSmB and had a negative impact on its fatigue resistance, while the joint rejuvenation of 3 wt% PU and 10 wt% AO not only gave a better high-temperature property to aged SBSmB but could also have the capacity to improve its fatigue resistance. Compared to virgin SBSmB, PU/AO rejuvenated SBSmB has comparative low-temperature viscoelastic behavior characteristics and a much better resistance to medium-high-temperature elastic deformation. [ABSTRACT FROM AUTHOR]

The oxygen vacancies and interface reconstruction synergistically enhance the piezo-photocatalytic performance of Bi 2 MoO 6-x -TiO 2 , which promotes the efficient degradation of gatifloxacin to small molecular structure after multi-step reaction. [Display omitted] • Successfully prepared a heterojunction Bi 2 MoO 6-x -TiO 2. • Bi 2 MoO 6-x -TiO 2 exhibits excellent piezo-photocatalytic degradation performance. • Oxygen vacancies induce the formation of Mo (Bi 2 MoO 6-x)-O (TiO 2) bonds at the interface. • Compressive stress enhances interfacial polarization and promotes electron transfer. • Compressive stress adjusts the d-band center to enhance adsorption performance. Construction of heterojunction piezo-photocatalysts is a promising approach to improve catalytic performance for solving environmental pollution issues. However, the mechanism of the synergistic effect of defects and piezoelectric fields on the interface polarization, charge transfer, and active sites in heterojunctions still needs to be further explored. Here, oxygen vacancy-rich Bi 2 MoO 6 (VBMO) and TiO 2 (TO) were combined into an S-scheme heterojunction (VBMO-xTO) by hydrothermal method for piezo-photocatalytic degradation of gatifloxacin (GAT). Experimental and theoretical results confirm that oxygen vacancies induce the formation of Mo (VBMO)-O (TO) bonds at the interface, which in turn aggravates the internal reconstruction of the heterojunction. Simultaneously, the formed interface bonds strengthen the interface bonding force, improve its piezoelectric polarization, and acts as an interface electron bridge to promote charge transfer. In addition, under the action of ultrasound, the piezoelectric field generated by the compressive stress regulates the electron distribution of the heterojunction and enhances its adsorption performance. Benefiting from the synergistic reinforcement mechanism, VBMO-15TO exhibits excellent piezo-photocatalytic degradation of GAT, and the degradation rate is 92.5 % in only 6 min. This study provides a reference for understanding the effect of defects on the piezoelectric properties of heterojunctions. [ABSTRACT FROM AUTHOR]

In recent years, the research and development of high-speed trains has advanced rapidly. The main development trends of high-speed trains are higher speeds, lower energy consumption, higher safety, and better environmental protection. The realization of a lightweight high-speed car body is one of the key features in the development trend of high-speed trains. Firstly, the basic dimensions of the car body’s geometric model are determined according to the external dimensions of the body of a CRH EMU, and the specific topology optimization design domain is selected to establish the finite element analysis model; secondly, the strength and modal analyses of the topology optimization design domain are carried out to check the accuracy of the design domain and provide a comparative analysis for subsequent design. Then, the variables, constraints, and objective functions of the topology optimization design are determined to establish the mathematical model of topology optimization, and the design domain is calculated for topology optimization under single and multiple conditions, respectively. Finally, based on the topology optimization calculation results, truss-type reconstruction modeling is carried out for the car body’s side walls, roof, underframe, end walls, and other parts. Compared with the conventional EMU body structure, the weight of the reconstructed body structure is reduced by about 18%. The results of the finite element analysis of the reconstructed car-body structure prove the reliability and safety of the structure, indicating that the reconstructed car-body scheme meets the corresponding performance indicators.

Abstract Electrochemical water splitting coupled with renewable energy offers a promising avenue for energy conversion and storage, but it is also extremely suppressed by the sluggish kinetics of oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). Herein, a multi‐layer architecture strategy was utilized by the in situ growth for cobalt phosphate of Hopeite‐like phase (Co‐H) on NiCo‐layered double hydroxide (NiCo‐LDH) to prepare a self‐supported electrode (Co‐H/NiCo@NF). The Co‐H formed over the NiCo‐LDH shows a unique sea urchin‐like morphology. The Co‐H/NiCo@NF displays excellent HER and OER activity, requiring only overpotentials of 180 mV and 350 mV to deliver 100 mA cm−2, consequently, be capable to generate an appealing cell potential of 1.76 V for overall water splitting at the corresponding current density. In addition, the prepared Co‐H/NiCo@NF has long‐term stability against 500 mA cm−2 and exhibits a trend of increased activity, which may associate with the structural reconstructions to form new phases and the strong bonding between layers. These findings demonstrate that the multi‐layer architecture with fine‐component modulation is a promising strategy for the development of robust and efficient cobalt phosphate electrocatalysts, and the role of multi‐layer in the evolution of structural reconstructions deserves further investigation.

Electrochemical nitrate reduction reaction (NO 3 RR) offers a promising technology for the synthesis of ammonia (NH 3 ) and removal of nitrate in wastewater. Herin, we fabricate a series of Fe 3 C nanoparticles in controllable pyridinic-N doped graphene (Fe 3 C@NG-X) by a self-sacrificing template method for the NO 3 RR. Fe 3 C@NG-10 exhibits high catalytic performance with a Faradaic efficiency (FE) of 94.03 % toward NH 3 production at -0.5 V vs. Reversible hydrogen electrode (RHE) and an NH 3 yield rate of 477.73 mmol h -1  g cat -1 concentration range (12.5-500 mM). During the electrocatalytic process, the material experienced structural reconstruction, forming Fe/Fe 3 - concentration range (12.5-500 mM). During the electrocatalytic process, the material experienced structural reconstruction, forming Fe/Fe 3 C@NG-X heterojunction. Experimental investigations demonstrate that the remarkable electrocatalytic activity is attributed to the high proportion of pyridinic-N content, and the reconstruction further enhances the overall reduction process., (© 2025 Wiley-VCH GmbH.)

Mixed transition‐metals (TM) based catalysts have shown huge promise for water splitting. Conventional synthesis of nanomaterials is strongly constrained by room‐temperature equilibria and Ostwald ripening. Ultra‐fast temperature cycling enables the synthesis of metastable metallic phases of high entropy alloy nanoparticles, which later transform to oxide/hydroxide nanoparticles upon use in aqueous electrolytes. Herein, an in situ synthesis of non‐noble metal high entropy oxide (HEO) catalysts on carbon fibers by rapid Joule heating and quenching is reported. Different compositions of ternary to senary (FeNiCoCrMnV) HEO nanoparticles show higher activity towards catalyzing the oxygen evolution reaction (OER) compared to a noble metal IrO2 catalyst. The synthesized HEO also show two orders of magnitude higher stability than IrO2, due to stronger carbide‐mediated intimacy with the substrate, activated through the OER process. Alloying elements Cr, Mn and V affect OER activity by promoting different oxidation states of the catalytically active TM (Fe, Ni and Co). Dissolution of less stable elements (Mn, V and Cr) leads to enhancements of OER activity. Dynamic structural and chemical perturbations of HEO oxide nanoparticles activate under OER conditions, leading to enlargement in ECSA by forming mixed single atom catalysts and ultra‐fine oxyhydroxide nanoparticles HEOs. [ABSTRACT FROM AUTHOR]

How in situ structural reconstructions affect the hydrogen evolution reaction (HER) activity of small Pd clusters is a long-standing problem in the field of heterogeneous catalysis. Herein, we reveal the structural evolution of Pdn (n = 6, 19, 44) clusters under the HER environment via stochastic global potential energy surface searching. We theoretically demonstrated that the HER activity of Pdn clusters first increases and then decreases under long-term working conditions. The intrinsic nature of these phenomenons includes interior H formations and structural reconstructions caused by the supersaturated adsorption of H atoms. This proves that carefully adjusting the hydrogenation degree of Pd clusters is a good strategy for improving the HER's catalytic performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Identification of structural reconstructions of catalysts are discussed. • The external and internal triggers of catalyst reconstruction are discussed. • In situ techniques and theoretical calculation to track reconstruction are discussed. • Strategies to manipulate the reconstructing behavior of catalysts are proposed. Advancing the development of CO 2 hydrogenation reaction to address the environmental challenges stemming from excessive CO 2 emissions requires the rational design of outstanding catalysts. The severe conditions of CO 2 hydrogenation reaction often result in the structural reconstruction of the catalyst. For catalysts, the identification of structural reconstructions, understanding the structure–performance relationships and the manipulation of reconstruction are critical issues. However, practical reactions often involve complex reconstructive behaviors (the dynamic changes of phase, morphology, interface, and chemical state) in catalysts. In this review, we discuss the fundamental types of catalyst reconstruction behavior and the correlation between reconstruction behavior and catalytic performance. Subsequently, in situ characterization techniques and theoretical simulation calculations for monitoring the reconstruction behavior under operational conditions were introduced. The external and internal triggers of catalyst structural reconstruction are further discussed. Finally, the strategies for manipulating catalyst reconstruction are proposed. From the perspective of active site evolution, it can stabilize the active site in the reaction and maintain high activity for a long time. From the point of view of electronic structure, the enhancement of electron transfer creates a prominent charge density gradient, resulting in a change in the adsorption site and capacity of the adsorbed species. This review provides new insights into the structural reconstruction and true active sites of CO 2 hydrogenation catalysts, offering guidance for the rational design of advanced catalysts. [ABSTRACT FROM AUTHOR]

Excellent OER catalysts can enhance the efficiency of hydrogen production from electrolytic water. The development of low-cost, abundant, and highly efficient catalysts remains crucial for the electrolytic hydrogen production industry. In this work, we have developed a highly efficient and cost-effective stainless steel-based OER catalyst using a strategy combining anodic corrosion and structural reconstruction. This approach is not only simple and easy to scale up production, but more importantly, it can also achieve controllable switching of lattice oxygen evolution mechanism (LOM). Specifically, in a 1 M KOH electrolyte, this catalyst achieves current densities of 500 mA/cm² and 1000 mA/cm² with remarkably low overpotentials of only 347 mV and 382 mV, respectively. Moreover, the catalyst exhibits exceptional stability even under high industrial current densities. In-situ differential electrochemical mass spectrometry (DEMS) experiments provide direct evidence of the transition from the adsorbate evolution mechanism (AEM) to the LOM. Through comprehensive characterizations and density functional theory (DFT) calculations, we have elucidated the underlying mechanism responsible for the improved performance and identified key factors influencing the induction of the LOM. This work provides support and new insights for the design and preparation of high-performance steel-based electrolytic water catalysts. In this work, we have developed a highly efficient and cost-effective stainless steel-based OER catalyst using a strategy combining anodic corrosion and structural reconstruction. This approach is not only simple and easy to scale up production, but more importantly, it can also achieve controllable switching of lattice oxygen evolution mechanism (LOM). Our study demonstrates that the SS-AC-SR exhibits remarkable OER performance, with impressively low overpotentials of 229 mV, 347 mV and 382 mV at current densities of 10, 500 and 1000 mA/cm2, respectively, in 1 M KOH. Furthermore, the catalyst demonstrates excellent stability even under high industrial current densities, showcasing its potential for industrial-scale green hydrogen production. [Display omitted] [ABSTRACT FROM AUTHOR]

Body fluid homeostasis is critical to survival. The integrity of the hypothalamo-neurohypophysial system (HNS) is an important basis of the precise regulation of body fluid metabolism and arginine vasopressin (AVP) hormone release. Clinically, some patients with central diabetes insipidus (CDI) due to HNS lesions can experience recovery compensation of body fluid metabolism. However, whether the hypothalamus has the potential for structural plasticity and self-repair under pathological conditions remains unclear. Here, we report the repair and reconstruction of a new neurohypophysis-like structure in the hypothalamic median eminence (ME) after pituitary stalk electrical lesion (PEL). We show that activated and proliferating adult neural progenitor cells differentiate into new mature neurons, which then integrate with remodeled AVP fibers to reconstruct the local AVP hormone release neural circuit in the ME after PEL. We found that the transcription factor of NK2 homeobox 1 (NKX2.1) and the sonic hedgehog signaling pathway, mediated by NKX2.1, are the key regulators of adult hypothalamic neurogenesis. Taken together, our study provides evidence that adult ME neurogenesis is involved in the structural reconstruction of the AVP release circuit and eventually restores body fluid metabolic homeostasis during hypothalamic self-repair. [ABSTRACT FROM AUTHOR]

Electrochemical structural reconstruction of catalysts may generate real active sites that differ from the initial catalyst, but is often ignored. Herein, combining in situ and ex situ techniques, it is identified that the bismuth nanosheets (NS) dotted with large numbers of coordinatively unsaturated pit sites is produced via the in situ structural reconstruction of Bi(OH)3 NS. Such reconstructed Bi NS shows greatly improved catalytic activity toward CO2 electroreduction, with a 2.6‐fold increase in current density compared with intact Bi NS, high Faradaic efficiency for HCOO− production (>95%), and an extraordinary turnover frequency of 0.35 s−1 at −0.98 VRHE. In addition, it delivers industrial‐relevant current density of 325 mA cm−2 without compromising selectivity in a flow cell. The mechanistic studies demonstrate that these coordinatively unsaturated sites acting as the real active sites favor the stabilization of key intermediate *OCHO, which thus facilitate the reaction kinetics for HCOO− production. This work not only provides a unique perspective on the construction of efficient catalysts for CO2 electroreduction, but also implies the importance in recognition of structural reconstruction. [ABSTRACT FROM AUTHOR]

Based on the low‐cost and relatively high catalytic activity, considerable efforts have been devoted towards developing redox‐active transition metal (TM)‐oxygen electrocatalysts for the alkaline oxygen evolution reaction (OER) while the role of redox‐inactive alkaline earth metals has often been neglected in OER. Herein, for the first time, we developed a novel ternary intermetallic CaFe6Ge6 precatalyst, whose surface rapidly transforms into a porous ultrathin Ca−Fe−O heteroshell structure during alkaline OER through the oxidative leaching of surficial Ge. Benefiting from synergistic effects, this highly efficient OER‐active material with distinct Ca−Fe−O layers has a large electrochemical surface area and more exposed active Fe sites than a Ca‐free FeOx phase. Also, the presence of Ca in Ca−Fe−O is responsible for the enhanced transport and activation of hydroxyls and related OER reaction intermediate as unequivocally illustrated by a combination of quasi in‐situ Raman spectroscopy and various ex‐situ methods. [ABSTRACT FROM AUTHOR]

Structural reconstruction is a process commonly observed for Cu‐based catalysts in electrochemical CO2 reduction. The Cu‐based precatalysts with structural complexity often undergo sophisticated structural reconstruction processes, which may offer opportunities for enhancing the electrosynthesis of multicarbon products (C2+ products) but remain largely uncertain due to various new structural features possibly arising during the processes. In this work, the Cu2O superparticles with an assembly structure are demonstrated to undergo complicated structure evolution under electrochemical reduction condition, enabling highly selective CO2‐to‐C2+ products conversion in electrocatalysis. As revealed by electron microscopic characterization together with in situ X‐ray absorption spectroscopy and Raman spectroscopy, the building blocks inside the superparticle fuse to generate numerous grain boundaries while those in the outer shell detach to form nanogap structures that can efficiently confine OH− to induce high local pH. Such a combination of unique structural features with local reaction environment offers two important factors for facilitating C−C coupling. Consequently, the Cu2O superparticle‐derived catalyst achieves high faradaic efficiencies of 53.2% for C2H4 and 74.2% for C2+ products, surpassing the performance of geometrically simpler Cu2O cube‐derived catalyst and most reported Cu electrocatalysts under comparable conditions. This work provides insights for rationally designing highly selective CO2 reduction electrocatalysts by controlling structural reconstruction. [ABSTRACT FROM AUTHOR]

Carboxylic acid-based metal-organic frameworks (MOFs) are normally passed for the "pre-catalysts" for oxygen evolution reaction (OER) due to the hydroxides constructed in-situ during its alkaline hydrolysis process (AHP) in lye. Whereas, it remains a mystery that they show advantageous activity over prototypical hydroxides when they are directly acted as OER catalysts. Herein, we propose for the first time that the steric hindrance effect of Nafion can induce enhanced catalytic activity of such MOFs. Different from conventional catalysts without AHP, the Nafion with 3D structure weakens the AHP of Co-MOF nanoribbons, thus forming small size and low crystallinity species (cobalt hydroxide) with more active sites. And the existence of Nafion also optimizes its electronic structure, which is confirmed by transmission electron microscopy (TEM), in-situ UV absorption spectra, in-situ Raman spectroscopy and so on. Compared with Co-MOF-K obtained by directly immersing the Co-MOF nanoribbons in 1.0 M KOH, the Co-MOF-NK obtained by AHP of Co-MOF mixed with Nafion shows better catalytic activity. Based on the above inspiration, we realized the low overpotential of 268 mV at 10 mA·cm−2 by preparing CoFe-MOF-NK. This work provides a new understanding of the structural reconstruction of MOFs in the field of electrocatalysis. [ABSTRACT FROM AUTHOR]

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Aqueous zinc-ion batteries (AZIBs) have received comprehensive attention as promising candidates for large-scale energy storage owing to high security, low cost, and environmental friendliness. Developing appropriate cathode materials is of great significance for high-efficiency Zn2+ storage. Herein, we proposed an efficient in-situ electrochemical pretreatment strategy to unlock the potential of non-electrochemically active spinel MnV 2 O 4 via an irreversible phase reconstruction from crystalline structure to short-range ordered amorphous state. Specifically, the reconstructed electrodes not only deliver abundant active sites for Zn2+ ions accommodation, but also shorten diffusion paths for rapid reaction kinetics, thus achieving superior electrochemical properties. As revealed, the optimized electrodes present a prominent specific capacity of 445 mA h g−1 at 0.1 A g−1, a high capacity retention of 73.1 % over 2000 cycles at 5 A g−1, as well as exceptional energy density of 335 W h kg−1 and power density of 176 W kg−1 based on the mass of cathode. In addition, the reaction mechanism during Zn2+ ions storage process is systematically investigated by ex-situ X-ray diffraction and X-ray photoelectron spectroscopy. This in-situ electrochemical conversion mechanism sheds light on a new methodology of designing desirable cathode materials for aqueous ion batteries. The table of contents shows that the in-situ electrochemical pretreatment strategy is able to unlock the potential of non-electrochemically active spinel MnV 2 O 4 via an irreversible phase reconstruction from crystalline structure to amorphous state with abundant active sites and short diffusion paths, resulting in superior energy and power density for Zn2+ ions storage. [Display omitted] • In-situ electrochemical strategy is effective to active MnV 2 O 4 for Zn2+ storage. • The irreversible phase transition from crystalline to amorphous is investigated. • The reconstructed MnV 2 O 4 cathode exhibits excellent electrochemical performances. [ABSTRACT FROM AUTHOR]

A facile strategy is developed to synthesize NiFe-MIL-88A electrocatalysts with high efficient electrocatalytic performance, the introduction of Ni atoms effectively modulates the electronic structure of the bimetallic MOF. [Display omitted] • A facile strategy is developed to synthesize NiFe-MIL-88A@NF electrocatalyst. • NiFe-MIL-88A@NF electrode exhibits excellent electrocatalytic activity and stability. • The introduction of Ni can modulate the d-band center and ƒ e of the NiFe bimetallic MOF to enhance the adsorption capacity for intermediates. Oxygen Evolution Reaction (OER) is a critical half-reaction that hinders water decomposition due to its sluggish kinetics. Developing efficient, stable electrocatalysts for OER is crucial for addressing the challenges in energy crisis and green hydrogen production. Compared to single-metal Metal-Organic Frameworks (MOFs), synergistic interactions between metal ions in bimetallic MOFs provide sufficient space for tuning the electronic structure and oxygen-containing intermediate adsorption energies, and therefore bimetallic MOFs shows great potential in enhancing the OER kinetics. In this work, NiFe-MIL-88A nanosheets were synthesized on nickel foam via a facile one-step hydrothermal method. The catalyst exhibited exceptional OER performance in 1.0 M KOH solution. Notably, it achieved a current density of 50 mA cm−2 at a low overpotential of 220 mV and displayed a Tafel slope of 43.2 mV/dec. Furthermore, it had impressive electrocatalytic durability suitable for commercial applications. This work elucidates the performance enhancement of NiFe bimetallic MOF from the perspective of electron migration. In-situ Raman spectroscopy was adopted to investigate the structural reconfiguration of the catalyst to reveal the true catalytic active sites. First-principle calculation demonstrate that introduction of Ni atoms with low electronegativity is conducive to optimizing the catalytic d-band center and ƒ e value. This work provides insights for the designing bimetallic MOFs with superior OER performance. [ABSTRACT FROM AUTHOR]

Constructing heterojunctions has emerged as a widely embraced strategy for augmenting piezo-photocatalytic activities. However, the synergistic pressure response, the construction of charge transfer, polar direction sites and active site are often left in the basket. Here, the carboxylated C 3 N 4 and Bi 2 MoO 6 S-scheme heterostructure was elaborately designed for piezo-photocatalytic nitrogen oxidation towards nitric acid. Extensive research evidence proves that Bi-COOH interaction between Bi 2 MoO 6 and g-C 3 N 4 leads to the occurrence of polarity interaction and structural reconstruction. Those initiatives facilitate the efficient distribution of charges and acts as a pathway for carrier migration, thereby promoting charge transfer and the large intrinsic dipole moment. Furthermore, the combination of polarity interaction and structural reconstruction strengthens N 2 polarization and electron transfer, facilitating the breaking of N N bonds and reducing activation energy. Consequently, the optimal BCO-3 catalyst revealed outstanding nitric acid production rates of 5930 μg g−1 h−1 under the stimulation of ultrasonic and light illumination, which is 3.66 times higher than that of C 3 N 4 -Bi 2 MoO 6 heterostructure and superiors to various piezo-photocatalysts. Our research endeavors present promising prospects for the design of advanced catalysts and contribute to a profound comprehension of molecular activation processes in heterojunction. [Display omitted] • Synergistic polarity interaction and structural reconstruction in Bi 2 MoO 6 / carboxylated C 3 N 4 heterojunction. • Bi-COOH interaction leads to the occurrence of polarity interaction and structural reconstruction. • Bi-COOH interaction facilitate the efficient distribution of charges and acts as a pathway for carrier migration. • It strengthens the polarization, activation, and adsorption of N 2. • Bi 2 MoO 6 /C 3 N 4 exhibited excellent piezo-photocatalytic activity and stability. [ABSTRACT FROM AUTHOR]

Electrooxidation of organics using electrons as oxidants is a clean approach to produce commodity chemicals. However, designing an electrocatalyst with superior performance at low cell voltage remains a challenge. In this study, a series of V S -Co@Co 9 S 8 electrocatalysts were fabricated by thermal reduction method using MOFs as templates. The catalytic oxidation performance and reaction mechanism of such specimens for benzyl alcohol were comprehensively analyzed by electrochemical measurement method and ex-situ structure characterization. The results show that Co@Co 9 S 8 -30 M has a unique three-dimensional (3D) micro cubic structure with abundant S vacancy (V S). These features accelerate the electrons and substrate transfer as well as provide plentiful active sites for benzyl alcohol electrooxidation reaction (BAOR). Consequently, the Co@Co 9 S 8 -30 M presented outstanding catalytic activity. The overpotential of 10 mA cm−2 (η 10) was only 265.4 mV for BAOR. The conversion rate and benzoic acid selectivity were achieved to 72% and 90%, respectively. Particularly, the formation rate of benzoic acid was 7.247 mmol·g cat.−1·h−1. Moreover, the Co@Co 9 S 8 -30 M exhibited superior durability over 135 h. The coordination number of octahedral metal sites in Co 9 S 8 did not match the number of Co 3 d orbital electrons, resulting in the weakening of bonding strength between Co and S elements. Thus, the Co@Co 9 S 8 was reconstructed to Co 3 O 4 @CoOOH. Based on this assessment, the Co 3 O 4 @CoOOH was the active site of BAOR. This work provides theoretical guidance for the design of Co-based catalysts. [Display omitted] [ABSTRACT FROM AUTHOR]

Metal‐organic frameworks (MOFs) have been widely studied for electrochemical CO2 reduction reaction (CO2RR). However, the application of negative potential tends to trigger its structural reconstruction and component alteration. It is of great significance to study the relationship between the structural evolution of MOF‐derived materials and product selectivity under the reaction conditions. Herein, we fabricate a HKUST‐1 thin film on carbon fiber paper by a facile electrodeposition approach to investigate the variation of CO2RR activity with HKUST‐1 structural reconstruction. During the CO2RR process, the HKUST‐1 reconstructs into two structures successively over time: 3D nanospheres composed of numerous small fragments and 3D nano‐network composed of cross‐linked nanobelts in different directions. The former shows a better catalytic activity due to more active sites, lower charge transfer resistance and higher Cu+/Cu0 ratio. The optimum Faradaic efficiency (FE) of C2 products (ethylene and ethanol) reaches 58.6 % at −0.98 V versus reversible hydrogen electrode (RHE). [ABSTRACT FROM AUTHOR]

Injured bone tissues can be healed with bone grafts, but this procedure may cause intense pain to the patient. A slow and localized delivery of nonsteroidal anti-inflammatory drugs (NSAIDs) could help to reduce the pain without affecting bone regeneration. The objective of the present study was to use [Mg-Al]-layered double hydroxide (LDH) as a matrix for controlled release of sodium naproxen (NAP). This system could be applied in biomaterial formulations (such as bone grafts) to achieve a local delivery of naproxen. [Mg-Al]-LDH successfully incorporated up to 80% (w/w) of naproxen by the structural reconstruction route, with the [Mg-Al]-LDH interlayer space increasing by 0.55 nm, corresponding to the drug molecule size. The evaluation of the naproxen release kinetics showed that 40% of the drug was delivered over 48 h in aqueous medium (pH 7.4 ± 0.1), indicating the potential of [Mg-Al]-LDH/NAP for local release of naproxen at adequate concentrations. Kinetic modeling showed that the naproxen release process was closely related to the Higuchi model, which considers the drug release as a diffusional process based on Fick's law. The chemical stability of NAP after the release tests was verified by 1H NMR. The [Mg-Al]-LDH/NAP also exhibited low cytotoxicity toward fibroblast cells (L929 cell line), without modifications in their morphology and adhesion capacity. These results describe a suitable approach for preparing efficient systems for local delivery of nonsteroidal anti-inflammatory drugs for biomedical applications. [ABSTRACT FROM AUTHOR]

The natural structure of columnar jointed rock mass (CJRM) is complex because it was formed during the cooling process of volcanic rock. In CJRM, both the structures of columns and columnar joints are oriented, and the exact mechanical properties are difficult to obtain due to the lack of testing samples that correspond to natural rock masses. Therefore, this brings challenges for underground engineering construction related to CJRM. The reconstruction of CJRM is an effective method that can be used to resolve this problem. However, using an artificial method means that it is difficult to consider the detail of structures, such as irregular columns, columnar joints, and microcracks in columns. With the development of 3D printing (3DP) technology, a useful method for the accurate reconstruction of CJRM has been provided. In this paper, based on laboratory and in situ tests, the structural characteristics and mechanical properties of CJRM in Baihetan Hydropower Station will be investigated. Then, based on the accurate structural reconstruction of CJRM that considers the similarity constant between in situ and laboratory tests, the mechanical anisotropy and failure modes of 3DP CJRM specimens will be investigated. The results show that 3DP is an effective method for reconstructing the structures of CJRM and that it is necessary to consider the detail of the structures, such as the irregularity of columns, columnar joints, and microcracks. In addition, the unfavorable loading angles between the axis of the column and loading direction were obtained. The 3DP results presented in this paper could provide a reference to help understand the structural characteristics of CJRM. [ABSTRACT FROM AUTHOR]