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Graph Transformers (GTs) have achieved impressive results on various graph-related tasks. However, the huge computational cost of GTs hinders their deployment and application, especially in resource-constrained environments. Therefore, in this paper, we explore the feasibility of sparsifying GTs, a significant yet under-explored topic. We first discuss the redundancy of GTs based on the characteristics of existing GT models, and then propose a comprehensive G raph T ransformer SP arsification (GTSP) framework that helps to reduce the computational complexity of GTs from four dimensions: the input graph data, attention heads, model layers, and model weights. Specifically, GTSP designs differentiable masks for each individual compressible component, enabling effective end-to-end pruning. We examine our GTSP through extensive experiments on prominent GTs, including GraphTrans, Graphormer, and GraphGPS. The experimental results demonstrate that GTSP effectively reduces computational costs, with only marginal decreases in accuracy or, in some instances, even improvements. For example, GTSP results in a 30% reduction in Floating Point Operations while contributing to a 1.8% increase in Area Under the Curve accuracy on the OGBG-HIV dataset. Furthermore, we provide several insights on the characteristics of attention heads and the behavior of attention mechanisms, all of which have immense potential to inspire future research endeavors in this domain. Our code is available at https://github.com/LiuChuang0059/GTSP. [ABSTRACT FROM AUTHOR]

The corrosion in 3.5 wt% NaCl solution caused a mitigated weight loss of the aluminum alloy 7050 (AA7050) under cavitation erosion condition. The mechanism was observed using high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electro back-scattered diffraction (EBSD), and potentiodynamic polarization. Both in deionized water and in 3.5 wt% NaCl solution, the cavitation erosion degradation of the AA7050 was mainly attributed to fatigue fracture like peeling off of surface layer materials. The corrosion significantly mitigated the weight loss of AA7050 under cavitation erosion condition because the loose surface oxide film (generated by corrosion) dissipated the cavitation impact energy and therefore alleviated the stress concentration on the alloy surface. • The effects of corrosion on the cavitation erosion of the aluminum alloy 7050 (AA7050) was studied. • Corrosion generated protective oxide film was the crucial factor in the cavitation erosion resistance of the AA7050. • Dislocation lines tended to concentrate at the grain boundaries and at the second phase boundaries during cavitation erosion. • Under a cavitation erosion condition, the stress on the surface of the AA7050 was mitigated by corrosion. [ABSTRACT FROM AUTHOR]

As dynamic graphs have become indispensable in numerous fields due to their capacity to represent evolving relationships over time, there has been a concomitant increase in the development of Temporal Graph Neural Networks (TGNNs). When training TGNNs for dynamic graph link prediction, the commonly used negative sampling method often produces starkly contrasting samples, which can lead the model to overfit these pronounced differences and compromise its ability to generalize effectively to new data. To address this challenge, we introduce an innovative negative sampling approach named Enhanced Negative Sampling (ENS). This strategy takes into account two pervasive traits observed in dynamic graphs: (1) Historical dependence, indicating that nodes frequently reestablish connections they held in the past, and (2) Temporal proximity preference, which posits that nodes are more inclined to connect with those they have recently interacted with. Specifically, our technique employs a designed scheduling function to strategically control the progression of difficulty of the negative samples throughout the training. This ensures that the training progresses in a balanced manner, becoming incrementally challenging, and thereby enhancing TGNNs' proficiency in predicting links within dynamic graphs. In our empirical evaluation across multiple datasets, we discerned that our ENS, when integrated as a modular component, notably augments the performance of four SOTA baselines. Additionally, we further investigated the applicability of ENS in handling dynamic graphs of varied attributes. Our code is available at https://github.com/qqaazxddrr/ENS. [ABSTRACT FROM AUTHOR]

Here, we report the synthesis of activated NiCo LDH to immobilize Pt, Ir and Rh single atoms for hydrogen evolution reaction. The Pt/A-NiCo LDH electrocatalyst exhibits the highest catalytic ability with a low overpotential of 16 mV to achieve a current density of 10 mA cm−2 and a mass activity about 24.8-fold that of commercial Pt/C. The results suggest that the Pt single atom catalyst can not only accelerate the Volmer steps in alkaline media, but also optimize the hydrogen adsorption process, improving the HER catalytic activity. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to clarify the effect of compressive stress on cavitation-erosion corrosion behavior of 304 stainless steel. Design/methodology/approach: Compressive stresses of 60 MPa and 120 MPa were applied to 304 stainless steel through a self-designed loading device, and cavitation erosion-corrosion tests were performed using an ultrasonically vibratory apparatus. Scanning electron microscope and X-ray diffraction were used to analyze the microstructure evolution, and corrosion behavior was studied by electrochemical analysis. Findings: The cavitation weight loss of 304 stainless steel decreased with the compressive stress. After cavitation corroded for 8 h, the weight loss for the specimen with 120 MPa compressive stress was 5.11 mg/cm2, which was reduced by 56.7% from that of the specimen without loading stress (11.79 mg/cm2). The reason can be attributed to that compressive stress promoted the deformation-induced martensitic transformation during the cavitation process, which could not only provide a cushioning effect by absorbing cavitation impact energy but also improve the hardness of 304 stainless steel. Originality/value: Compressive stress was found to restrain the cavitation damage on 304 stainless steel, and the corresponding mechanism was proposed. [ABSTRACT FROM AUTHOR]

Ion exchange membranes (IEMs) play important roles in energy generation and storage field, such as fuel cell, flow battery, however, a major barrier in the way of large‐scale application is the high cost of membranes (e.g., Nafion membranes price generally exceeds USD$ 200 m−2). The membrane‐less technology is one of the promising approaches to solve the problem and thus has attracted much attention and been explored in a variety of research paths. This review introduces one of the representative membrane‐less battery types, Biphasic membrane‐less redox batteries that eliminate the IEMs according to the principle of solvent immiscibility and realizes the phase splitting in a thermodynamically stable state. It is systematically classified and summarizes their performances as well as the problems they are suffering from, and then several effective solutions are proposed based on the modification of electrodes and electrolytes. Finally, special attention is given to the challenges and prospects of Biphasic membrane‐less redox batteries, which could contribute to the development of membrane‐less batteries. [ABSTRACT FROM AUTHOR]

Background: Solitary fibrous tumor of the pleura (SFTP) is a rare mesenchymal tumor that arises at various sites and typically originates from the pleura. Most patients with SFTPs are asymptomatic, unless the tumor is large. Approximately 20% of SFTP cases are malignant. There are few reports on imaging diagnoses and interventional treatments of SFTP. Here, we report a case of a giant SFTP that exhibited malignant behavior and underwent successful resection after embolization of the main supply artery of the tumor.Case Presentation: We report a clinical case of a giant SFTP in a 66-year-old Chinese female patient complaining of chest tightness and cough for more than 2 months. Ten years ago, the patient had undergone a chest CT scan at a local hospital for cough. Computed tomography (CT) had revealed a mass in the right thoracic region, which was misdiagnosed as a pulmonary abscess by CT-guided biopsy. Therefore, the patient did not receive appropriate/complete treatment at that time. She was hospitalized again, because CT showed significant enlargement of the right thoracic mass, which caused her obvious symptoms of discomfort. The pathological results of CT-guided biopsy at our hospital confirmed SFTP. Considering the large size of the tumor and the rich blood supply, some of the main blood vessels were treated with embolization before surgical resection. A large tumor, about 23 cm × 16 cm × 15 cm in size, was then successfully removed by thoracic surgery. The diagnosis of malignant SFTP was confirmed by surgical pathology and immunohistochemistry.Conclusion: Imaging findings of SFTPs are not characteristic, especially when a tumor is large, the diagnosis is difficult, and the final diagnosis still depends on histological and immunohistochemical examinations. The two-stage surgical treatment described here, which involves first embolization of the main supplying artery of the large tumor and then complete surgical resection, is effective and safe for SFTPs. Whether needle biopsy or vascular embolization is performed, intervention plays a crucial role in the diagnosis and treatment of patients with SFTPs. [ABSTRACT FROM AUTHOR]

Facilitating the cleavage of a NN bond and suppressing the competition hydrogen evolution reaction is essential, and but still remains a challenge in nitrogen reduction reaction (NRR). Crystal phase tailoring is an effective approach to optimize the energy barrier during the NRR process to improve the catalytic efficiency. Herein, a boron‐doping strategy to induce phase transfer from hexagonal Mo2C to cubic Mo2C for regulating the electronic structure and catalytic properties of electrocatalysts toward NRR is reported. The B doped cubic Mo2C is found to increase the exposure of active sites, regulate the d band center of Mo for enhancing the adsorption and activation of nitrogen, and reduce the energy barrier of NRR pathway, giving rise to a high ammonia yield of 52.1 μg h−1 mg−1 at −0.6 V versus reversible hydrogen electrode under ambient conditions. More importantly, the hydrogen adsorption on the surface of electrocatalyst is significantly inhibited due to the B‐doping, further improving the faradic efficiency to 36.9%, which is 4 times that of hexagonal Mo2C (9%). This work not only sheds light on the atomic‐scale design of efficient NRR electrocatalysts, but also provides a promising avenue for synchronizing the catalytic activity and selectivity for catalytic reactions. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to study the effect of Hg2+ on the corrosion behavior of Al–2%Zn coatings on AA5083 in 3.5 Wt.% NaCl solution. Design/methodology/approach: Potentiodynamic polarization and electrochemical impedance spectroscopy are used to investigate the effect of Hg2+ on the corrosion behavior. The surface and cross-sectional morphology are characterized by scanning electron microscopy and energy dispersive spectroscopy (EDS) to further reveal the corrosion mechanism of Hg2+. Findings: The results show that the corrosion behavior of the coating changes significantly as the concentration of Hg2+ increases from 5 to 30 μg/L. The corrosion production film can inhibit the corrosion process when Hg2+ concentration is in the range of 0.5–5 μg/L, while Hg2+ can promote the corrosion process significantly when its concentration reaches to 30 μg/L. The generation rate of dense oxide film on the coating surface is faster than dissolution rate when the concentration of Hg2+ is in the range of 0–5 μg/L, which makes the coating "self-healing" and thus slightly slows down the corrosion rate. The EDS analysis shows that excessive Hg2+ are preferentially deposited at locations with inhomogeneous electrochemical properties, which in turn accelerates corrosion. Originality/value: The corrosion resistance of Al-based coatings is significantly affected by Hg2+ in seawater. Thus, it is important to explain the corrosion mechanism of Al–2%Zn coatings under the combined effect of Hg2+ and Cl− in 3.5 Wt.% NaCl solution. [ABSTRACT FROM AUTHOR]

Transition metal chalcogenides (TMCs) have been identified as pre‐electrocatalysts for the oxygen evolution reaction (OER) and the high valent TMs in the in situ generated oxyhydroxides are considered to be the real OER catalytic center. However, the role of chalcogens for OER process has been ignored and not fully elucidated. Herein, it is discovered that about 2.8–3.5% of chalcogens remain in as oxidized derivatives at a steady state, which plays a vital role for enhancing the catalytic activity. A facile and spontaneous sulfurizing method is developed to synthesize sulfur‐doped NiCo‐(oxy)hydroxysulfides (NCOSH) nanosheets, in which the sulfur can directly bond with high‐valence TMs and keep them stable for OER catalysis. Theoretical and experimental results suggest that the S‐coordination in NCOSH can cause bond length strengthening and electronic modulation between TM‐S and TM‐O, thus enhancing the oxidation activity and stability of high‐valence TMs in NCOSH. Consequently, the as‐obtained NCOSH exhibits superior bifunctional activities and durability for oxygen electrocatalytic reactions, and also serves as a superb air cathode in rechargeable solid state Zn‐air batteries. This work sheds light on the rational design of (oxy)hydroxysulfides as efficient electrocatalysts and gains deeper fundamental insights on the enhancing mechanism of S in oxyhydroxysulfides for diverse electrochemical applications. [ABSTRACT FROM AUTHOR]

The application of NaCl-based aluminum-air batteries is limited due to the passivation of the aluminum anode. In an effort to solve this problem, this work studied the influence of different concentrations of Ga3+ additives on the discharge behavior of Al in the NaCl electrolyte. The results of both experiments and theoretical calculations have shown that commercial purity aluminum could be significantly activated by Ga3+. Based on microstructure observations and electrochemical impedance spectroscopy, the influence activation mechanism of Ga3+ on the discharge behavior of commercial purity Al is clarified. The addition of Ga3+ biased the surface charge of aluminum along the activation direction, forming activation sites, and then destroyed the surface passivation film. Due to the formation of a gallium–aluminum amalgam, the Al-air battery had the best discharge characteristics in the electrolyte with 0.2 M Ga3+, and its discharge voltage reached 0.9734 V with a remarkable increase compared with that of NaCl solution (0.4228 V). Therefore, Ga3+ additive is a promising choice for NaCl-based Al-air batteries to improve their discharge voltage. [ABSTRACT FROM AUTHOR]

Long-time thermal batteries with high specific energy are crucial for improving the fast response ability of long-range weapons. Due to its high capacity, safety, and stability, the new sulfide cathode has attracted extensive attention. In this study, an FeS2@CoS2 composite cathode with a core–shell structure was prepared via a combination of hydrothermal and high-temperature vulcanization processes. The novel FeS2@CoS2 cathode not only delivers a high discharge voltage and output capacity, but also has high thermal stability and excellent conductivity. Benefiting from the synergistic effect of FeS2 and CoS2, the as-synthesized cathode yields a high specific capacity. At a large current density of 1 A/cm2, the utilization rate of FeS2@CoS2 cathode material can reach 72.33%, which is 8.23% higher than that of FeS2. Moreover, the maximum output capacity is up to 902 As/g, with a utilization rate of 79.02% at 500 mA/cm2. This novel design strategy holds great promise for the development and application of high-performance thermal batteries in the future. [ABSTRACT FROM AUTHOR]

The construction of binary metal Pd‐based catalysts is an effective strategy to enhance the activity of methanol oxidation reaction. Herein, atomically dispersed Ir single atoms doped to cuboctahedral Pd nanoparticles (Ir‐SAs/Pd) as efficient catalysts for alkaline methanol oxidation are prepared via a simple chemical reduction method. The synthetic Ir‐SAs/Pd catalysts exhibit the outstanding mass activity of about 1717.3 mA mgPd−1 compared with pure Pd and commercial Pd/C in electrooxidation for methanol. Meanwhile, the introduction of Ir single atoms enhances the CO tolerance of Pd nanoparticles to a large extent. On the basis of density functional theory results, the enhanced catalytic performance and CO tolerance rely on the effective improvement of the electron dominance near Fermi level and the negative shift of the d‐band center for Pd as a result of the electron redistribution between Pd and Ir atoms. This article will provide new insight into the design of high‐performance binary metal catalysts for methanol oxidation in alkaline media. [ABSTRACT FROM AUTHOR]

A facile and efficient approach to manufacturing optical devices with a plane graphene-coupled microfiber structure is proposed—attaching the optical microfiber onto a monolayer graphene-coated polydimethylsiloxane substrate. Such devices exhibit strong light–graphene interaction via the evanescent fields of the guided light in microfibers and show evident optical polarization and polarization-dependent saturable absorption effect. When the monolayer graphene with propagation distance is 2.5 mm, and the microfiber diameter is 3.9 μm, the polarization extinction ratio can reach up to 31.0 dB with the light wavelength at 1550 nm. The transmission in TM modes could be increased continuously by increasing the input power of light at 980 nm. The transmission with 3 and 10 dB modulation depths in TM modes could be achieved via 980 nm pump power of 15.1 and 66.1 mW, respectively, which is advantageous over unpolarized graphene-coupled microfiber devices. The proposed microfiber on graphene structure could efficiently integrate optical waveguides with two-dimensional materials, with great potential applications in optical polarizers, all-optical modulators, mode-locked fiber lasers, and sensors, especially for all-fiber systems. [ABSTRACT FROM AUTHOR]

Improving Pt catalytic activity and minimizing its usage as well as enhancing its stability is highly desirable for oxidation of methanol and ammonia in the field of electrocatalysis. Herein, the nanoporous Pt with coral‐like nanowires morphology/carbon fiber cloth electrocatalyst is reported, which is synthesized via a simple electrodeposition approach using phytantriol lyotropic liquid crystals as template. The obtained electrode with 3D coral‐like Pt nanowires architecture is composed of the orderly in situ grown Pt nanowires, and each individual Pt nanowire possesses a large number of nanopores. As expected, coral‐like Pt nanowires electrodes possess high electrochemical surface area of 43.1 m2 g‐1, almost twice that (25.4 m2 g‐1) of commercial Pt/C, and thus display superior catalytic activity of 343.1 mA mg‐1 and 72.0 mA mg‐1 toward methanol and ammonia oxidation, much higher than that of the commercial Pt/C (173.7 mA mg‐1 and 26.2 mA mg‐1), respectively. Additionally, the retention rates of oxidation peak current of coral‐like Pt nanowires electrode toward both methanol and ammonia oxidation after accelerated 100 cycles test achieve 82.1% and 85.6%, respectively, indicating the excellent stability of coral‐like Pt nanowires electrode. [ABSTRACT FROM AUTHOR]

Abundant surface structural defects can endow electrocatalysts with extraordinary physical and chemical characteristics. Herein, metastable Pd nanoparticles (NPs) with abundant twin boundaries (TBs) and atomic steps (ASs) anchored on a carbon substrate (TS‐Pd/C) are directly synthesized by a solid‐state thermal shock (TS) strategy. Molecular dynamics simulation indicates that the transient super cooling procedure after the TS synthesis can boost the formation of TBs. Benefitting from the abundant TBs and ASs, these metastable Pd NPs can serve as an advanced electrocatalyst for the ethanol oxidation reaction (EOR) with superior reactivity, stability, and CO tolerance in alkaline solutions, which far exceeds that of commercial Pd/C. The first‐principles calculations suggest that the defect structure dominated by TBs can achieve the spatial separation of the optimal adsorption sites for CO and OH. The CO can concentrate at optimal surface sites to minimize the number of poisoned active sites. The strong adsorption of OH can accelerate the EOR process and jointly promote the improvement of electrocatalytic reactivity. [ABSTRACT FROM AUTHOR]

Owing to its unique atomic arrangement and electronic structure, metallic glass (MG) has been widely investigated in the field of energy storage and conversion. In the past few decades, multiple strategies have been developed to synthesize bulk and nanosized MG based materials. Here, combining the structure–activity relationship of MG with electrochemical reaction kinetics, the substantial progress of glass structures in electrocatalytic processes are highlighted, including the hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction, methanol oxidation reaction, carbon dioxide reduction reaction, and nitrogen fixation. Meanwhile, applications of MG materials in energy storage devices, like supercapacitors and lithium‐ion batteries, are also introduced in detail. Finally, challenges and possibilities for reasonable design of highly‐efficient MG‐based electrode materials are proposed. The integration of high‐throughput methods, artificial intelligence technology, as well as advanced characterization techniques is fundamental to screen materials with remarkable performance. This review aims to deepen the understanding of the relationship between electronic structure and electrochemical performance, providing guidance for rational design of functional MG materials with outstanding activity, selectivity, and durability. [ABSTRACT FROM AUTHOR]

• Proposes a novel Multi-agent based IoT Network (MBIN) 5G architecture. • Introduces the intelligent cloud-based radio access technology to IoT services. • Presents the Advanced Cloud-Enabled Double Auction (ACEDA) system. Amid the rapid advancement of wireless network technologies, the forthcoming ubiquity of the Internet of Things (IoT) necessitates the development of sophisticated architectural frameworks and algorithms capable of handling the associated spectrum management complexities. This study proposes an innovative Mobile Broadband Internet of Things (MBIN) architecture, designed to facilitate efficient progression of the impending IoT revolution. The centerpiece of this architecture is a ground-breaking Advanced Cloud-Enabled Double Auction (ACEDA) algorithm. Deployed within the MBIN framework, this mechanism optimizes the sharing of spectrum resources, thereby enhancing the performance of the IoT structure. Theoretical grounding, algorithmic implementation, simulation results, and user satisfaction analysis are discussed in-depth to validate the efficacy of this approach. [ABSTRACT FROM AUTHOR]

Since boron powder has the highest volume energy density, it has long been desired for use as fuel in aerospace and other fields. However, boron has poor ignition performance and low combustion efficiency due to uneven microstructure and oxide layers of boron. Here, we report a facile strategy to prepare zero-dimensional boron nanospheres from micrometer-scale amorphous boron through ultrasound-assisted in-situ stabilization of heteroatoms for inhibition of boron oxide layer by using hexachlorocyclotriphosphazene (HCCP) and 4,4′-sulfonyldiphenol (BPS) polycondensation and carbonization. The diameter of the obtained boron nanospheres was in the range of 500–800 nm, which is the smallest reported diameter of regular boron nanoparticles. The initial reaction temperature of CPZS@B-1.0 decreased from 791.1 to 641.7 °C, and the ignition delay time of 20 wt% CPZS@B-1.0/RP-3 nanofluid fuel decreased to 393 ms. The addition of CPZS@B promoted RP-3 oxidation at both low temperatures (<200 °C) and high temperatures (>200 °C) by in-situ FTIR analysis. Notably, the prepared zero-dimensional nano-boron exhibited removal of surface oxidation and complete combustion degree (from 42.06 % to 80.36 %). This work provides a new method for the preparation of nano-boron and a solution for increasing the fuel energy density of hydrocarbon fuels. [Display omitted] • Zero-dimensional boron nanospheres were prepared through ultrasound-assisted in-situ stabilization of heteroatoms. • The diameter of the zero-dimensional boron is currently the smallest reported diameter of regular boron nanoparticles. • 20 wt% CPZS@B-1.0/RP-3 nanofluid fuel exhibited excellent ignition and considerably enhanced combustion performance. • Dual functional catalysis of the coated CPZS layer for both boron and RP-3 was proposed. [ABSTRACT FROM AUTHOR]

While amorphous metal oxides exhibit potential advantages in terms of energy conversion and storage, they undergo unavoidable and uncontrollable reconstruction during electrocatalysis. Monitoring the probable reconstruction of catalytic materials during operation is crucial for identifying the practical active sites. In this study, the amorphous In-doped SnO x (a-In-SnO x) was selected for the in-situ reconstruction of highly active structures. In/ex-situ electron microscopy revealed that the intricate reconstruction of a-In-SnO x could be divided into three states: initial, activated, and deactivated. The a-In-SnO x reconstructed amorphous–crystalline In-doped SnO 2 heterostructure for highly efficient CO 2 electroreduction. Benefiting from the heterostructure, the amorphous-crystalline In-doped SnO 2 (a/c-In-SnO 2) exhibited potential CO 2 RR performance with a maximum Faraday efficiency of 94.6% at −1.0 V (vs. RHE) and a current density of 209 mA cm–2 at −1.4 V (vs. RHE). This work represents significant advancements in design of active amorphous–crystalline heterostructures during the reconstruction process and establishes a dynamic evolution mechanism. [Display omitted] • An amorphous engineering strategy was explored for developing advanced electrocatalysts for CO 2 RR. • A universal regulation for the reconstruction process of amorphous materials during CO 2 RR was summarized. • A dynamic structure-function relationship was established on the amorphous In-SnO x with three states. • The in-situ formed amorphous–crystalline In-SnO 2 heterostructure was demonstrated to be highly active for CO 2 RR. [ABSTRACT FROM AUTHOR]

Dendritic growth is a common behavior during the electrodeposition of zinc, which degrades the compactness and thickness uniformity of the zinc film. In this work, a series of quaternary ammonium compounds (QAC) with different non-polar groups (based on the number of carbon atoms in non-polar groups represented as C1, C4, C8, C12 and C16, respectively) were introduced into the basic electrolyte to inhibit the zinc dendritic growth. The results showed that the deposition of zinc became smoother with the increase of non-polar group length, which was attributed to the fact that the non-polar groups of the additive limit the random diffusion of Zn2+ and changed the adsorption state of the surface, so that a uniform zinc film was obtained. Meanwhile, the Zn-Zn symmetric cells with the addition of C8 achieved a stable cycle time of over 600 h. But with the further increase of length (C12 and C16), the migration of Zn2+ to the electrode surface became extremely difficult for strong steric hindrance, resulting in a rough deposition morphology. • The non-polar groups of the selected additives have a hindering effect on zinc ions. • Regulating the hydrocarbon chain length of the nonpolar group of the additive change the zinc film morphology. • The additive with appropriate hydrocarbon chain length obtain uniform zinc deposition. [ABSTRACT FROM AUTHOR]

A structure of {[(Co-DLC)/DLC] X } n Multilayered Nanocomposite Films (MNF) is designed by inserting pure DLC high-resistance layers into Co-DLC nanocomposite film, which consists of alternating Co-DLC and DLC layers were prepared by magnetron sputtering. The electrochemical behavior and magnetic property of the films are modulated by varying the number of deposition cycles (n) and the thickness of one single-cycle (X). The electrochemical results show that this MNF structure significantly improves the corrosion resistance of the films owing to the clear interfaces, which block the micropores penetrating the films. Compared to the co-sputtering film, as the number of cycles n increases to 7, the corrosion resistance is enhanced by one order of magnitude from 2.3 × 104 to 2.2 × 105 Ω·cm2. However, the interfaces between the Co-DLC and DLC layer become blurred when the thickness of one single-cycle X is lower than 30 nm, and the corrosion resistance decreases to 3.7 × 104 Ω·cm2. In terms of magnetism, the multilayer structure helps to regulate the homogeneity of Co particle size. As X increases from 30 to 100 nm, the Co particle size increases from 2.7 to 4.7 nm, and the saturation magnetization intensity (M s) of superparamagnetic property in the films increases from 2.8 to 8.2 mT. As X increases, the remanent magnetization ratio (M r / M s) decreases and reaches 0.011 at X = 100 nm, which is about one order of magnitude smaller than that of the co-sputtering film. This result indicates that the MNF have better superparamagnetic property. It is noteworthy that {[(Co-DLC)/DLC] X } n MNF with X ranging from 100 to 40 nm and n ranging from 3 to 7 can achieve high corrosion resistance and superparamagnetic property, simultaneously. • {[(Co-DLC)/DLC] X } n multilayered nanocomposite films (MNF) are constructed. • Micropores are blocked by multilayer interfaces to improve corrosion resistance. • High anticorrosion and superparamagnetic property are achieved, simultaneously. [ABSTRACT FROM AUTHOR]

Industrial manufacturing, agricultural production, and domestic waste have led to severe environmental pollution, significantly impacting human health and the environment. The analysis of complex organic pollutants in aquatic environments is an inevitable issue in environmental monitoring. This paper introduces a tapered fiber ring sensor based on mid-infrared fiber evanescent wave spectroscopy (MIR-FEWS), which is one of the emerging technologies for detecting the food and chemical industry, environmental monitoring, battery chemistry, and medical applications. The sensor was prepared by tapering and bending a Ge 10 As 30 Se 38 Te 22 (GAST) infrared fiber. The influence of parameters such as waist diameter (d w), bending radius (r b), and bending circles (c b) on the sensor performance was discussed with the COMSOL simulation results. The optimal performance sensor with parameters d w = 50 µm, r b = 0.5 mm, and c b = 4 has a sensitivity of 1.490 ± 0.024 a.u./vol% and a limit of detection (LoD) of 0.058 ± 0.001 vol% for ethanol (CH 3 CH 2 OH) solutions. The hydrophobicity of the GAST fiber improves the sensitivity for detecting benzaldehyde (C 6 H 5 CHO) in the benzyl alcohol (C 6 H 5 CH 2 OH) and C 6 H 5 CHO aqueous solution. Finally, we successfully identified three organic compounds, C 6 H 5 CH 2 OH, C 6 H 5 CHO, and acetonitrile (CH 3 CN) in the wastewater and determined their concentrations as 0.460 ± 0.015 vol%, 0.176 ± 0.007 vol%, and 1.091 ± 0.024 vol%, respectively. The optical fiber sensor has great application potential in the field of multi-component organic matter analysis. • Infrared fiber ring sensor with high sensitivity (1.490 a.u./vol%) and low LoD (0.058 vol%) for ethanol is invented. • Qualitative and quantitative analysis of VOCs in wastewater are realized by infrared fiber ring sensor. • Compared with ATR-FTIR technique, infrared fiber ring sensor has higher sensitivity and lower LoD. • The strong hydrophobicity of the fiber improves the sensitivity to detect aldehydes. [ABSTRACT FROM AUTHOR]

The microstructural transformation, strengthening and stress corrosion cracking (SCC) mechanism upon brazing and subsequent artificial aging in the novel multi-layered sheets with adequate strength and corrosion resistance were clarified using comprehensive characterization methods, electrochemical measurements and slow strain tensile tests. The microstructure and overall strength of the brazed sheets was improved significantly due to the formation of various precipitates in the AA6A02 core after post-weld aging. The top layers can provide sacrificial protection to the core due to its more negative potential and higher localized corrosion reactivity caused by the large number of micro-galvanic couples formed between intermetallic particles and the substrate, thus increasing the corrosion resistance of the sheets. The galvanic effect and cathodic protection to the core diminished with increased aging time. The peak-aging and over-aging treatments led to reduced corrosion resistance and increased SCC susceptibility, attributing to the reduced potential difference and inefficient cathodic protection effect between the core and clad caused by full deposition of precipitates and severe intergranular corrosion of the core. • Effect of microstructural transformation on strengthening and corrosion mechanism of the novel multi-layered sheets are clarified. • Increased SCC sensitivity and reduced corrosion resistance due to peak-aging and over-aging. • Ineffective cathodic protection to the core after PA and OA. • SCC mechanisms are proposed and discussed. [ABSTRACT FROM AUTHOR]

Modulating the morphology of metal-organic frameworks (MOFs) has been identified as an effective strategy for enhancing the electrocatalytic performance of CO 2 reduction reactions (CO 2 RR). In this study, CAU-17 MOFs ([Bi(BTC)(H 2 O)]·2 H 2 O·MeOH) were prepared via a sonication-assisted method at room temperature, which is considered a simpler technique compared to the conventional hydrothermal method. Additionally, the morphology of CAU-17 MOFs was further regulated by incorporating a rare-earth metal (La), resulting in the observation of two distinct structures, i.e. CAU-17 hexagonal prism (CAU-17-HP) and CAU-17 layer (CAU-17-Layer). Compared to CAU-17-HP, CAU-17-Layer exhibits an excellent selectivity towards formate with the maximum Faradaic efficiency of 95.5% at − 1.1 V RHE in an H-cell. Subsequently, the limited catalytic activity of CAU-17-Layer was boosted by anchoring nano CeO 2 onto its surfaces (CeO 2 @CAU-17-Layer). The as-prepared composite catalyst demonstrated outstanding performance in the conversion of CO 2 to formate, with a current density surpassing − 100 mA cm-2 at potentials more negative than − 1.0 V RHE and reaching − 200 mA cm-2 at − 1.5 V RHE in a flow cell. This study demonstrates the significant potential of morphology-engineered and rare-earth metals composited MOFs in facilitating highly efficient reduction of CO 2. • Bismuth-based metal-organic frameworks (CAU-17 MOFs) were prepared via a sonication-assisted method at room temperature. • The morphology of CAU-17 MOFs was regulated by rare-earth metal (La). • Morphology engineering boosted the catalytic performance of CAU-17-MOFs. • When incorporating nano-CeO 2 into CAU-17-Layer, the current density reached − 200 mA cm-2 at − 1.5 V RHE. [ABSTRACT FROM AUTHOR]

• The effect of bending deformation on the corrosion behavior is discussed from the microstructure evolution and stress distribution. • Bending deformation causes stress concentration on both sides of the cross-sectional samples. • Discontinuous Si particles in non-brazed samples are unfavorable to the development of intergranular corrosion. • Si "needles" in brazed samples provide effective propagation path for intergranular corrosion. This study provides an insight into the effect of bending deformation on the corrosion behavior of non-brazed and brazed AA4343/AA4047/AA3003/AA4047/AA4343 composite sheet from the rolling direction (RD) and the transverse direction (TD) cross sections, by combining electrochemical measurements, scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD) techniques. Grain size had a greater effect on the corrosion resistance, as compared with the textures. Localized corrosion initiated from intermetallic particles (IMPs) for both non-brazed and brazed samples whether bending or not. After bending deformation, stress concentrations at the outer layer were found in non-brazed and brazed samples. For non-brazed samples, bending deformation had little effect on the corrosion behavior due to the absence of intergranular corrosion (IGC). For brazed samples, Si "needles" provided effective corrosion propagation path, leading to a reduction of corrosion resistance. [Display omitted] [ABSTRACT FROM AUTHOR]

• Co-ZnO non-uniform film structure is realized by adjusting sputtering pressure. • Suppression of Co clusters is obtained at high sputtering pressure. • High magnetoresistance and low-field sensitivity are simultaneously achieved. Co-ZnO metal–semiconductor nanocomposite films have become the focus of attention in recent years since their magnetoresistance (MR) effect at room temperature (RT). In this study, non-uniform Co-ZnO nanocomposite films were prepared by magnetron co-sputtering method. With sputtering pressure increasing, the formation of ferromagnetic Co clusters is suppressed effectively, and the metallic-state superparamagnetic Co particles are dispersed, which form the tunneling transport paths in the Co-ZnO films at high Co content. As the sputtering pressure increases from 0.3 Pa to 1.2 Pa, the RT -MR value of the films increases from 0.41 % to 11.85 %, and the saturation magnetization of the films rises from 6.3 kGs to 7.3 kGs and then decreases to 6.7 kGs. It is noteworthy that the low-field MR field sensitivity at 1000 Oe is enhanced by about 10 times from 0.5 Pa to 1.2 Pa. This provides a reference for the application of low-magnetic field detectors. [ABSTRACT FROM AUTHOR]

[Display omitted] • ZnO resistive switching film is prepared by one-step hydrothermal method. • Application of electric field can promote the formation of oxygen-vacancy in film. • High-low resistive switching behavior of film varies with oxygen vacancy content. ZnO resistive switching films were prepared on the surface of SS304 using hydrothermal method combined with heat treatment. The surface and cross-sectional morphology, composition, oxygen vacancy content and semiconductor type of ZnO films were characterized. The corrosion resistance and resistance switching properties of ZnO films were determined by electrochemical methods. The oxygen vacancy formation energy, surface adsorption energy and diffusion barrier of ZnO system were calculated using first-principles. The results show that the samples with 0.5 mol/L Zn2+ and 4 mol/L NaOH have the best performance, and its corrosion resistance efficiency can reach more than 99.5 %. Calculations show that the ZnO film containing oxygen vacancies still prevents the entry of Cl−, and applied electric field promotes the formation of oxygen vacancies and conductive filaments. Thus, polarization-immersion treatment can adjust the oxygen vacancy content in film, which enables film to switch between high and low resistance states, realizing the cyclic resistance-switching performance of film and greatly extending service life. [ABSTRACT FROM AUTHOR]

The effect of a 150 °C/144 h sensitization treatment on the localized corrosion of AA5083-O in a simulated dynamic seawater/air interface zone was investigated using electrochemical measurements and advanced characterization techniques. Sensitization resulted in an increase in the amount and the size of Al-Fe-Mn intermetallic particles (IMPs) in AA5083-O, and promoted the precipitation of β-Al 3 Mg 2 at grain boundaries in the AA5083-O. Severe pitting corrosion occurred on sensitized AA5083-O in the seawater/air interface zone, an uneven and loose surface film appeared in the presence of β-Al 3 Mg 2. • The effects of sensitization on localized corrosion of AA5083 in a dynamic seawater/air interface were investigated. • Sensitization increased the number and the size of Al-Fe-Mn intermetallic particles (IMPs). • Sensitization promoted β-Al 3 Mg 2 precipitation at the grain boundaries. • A loose and uneven surface film was induced on the sensitized AA5083-O. • Severe pitting corrosion occurred on sensitized AA5083-O exposed to the seawater/air interface zone. [ABSTRACT FROM AUTHOR]

The unique electronic structure and diverse elemental composition of high-entropy materials (HEMs) have already showcased remarkable properties in the realm of oxygen evolution reaction (OER). Despite this, the active sites and reaction pathways of HEMs have yet to be fully understood. Our findings indicate that the addition of Fe in HEMs results in a more positive valence state of metals, leading to the enhancement of the covalent characteristic of the M-O bond. Additionally, the predominant oxygen 2p orbitals near the Fermi level enables lattice oxygen to function as an OER center. Guided by theoretical calculations, we synthesized a nanoporous NiFeCoMnOOH (np-NiFeCoMnOOH) electrocatalyst exhibited a low overpotential of 194 mV at 10 mA cm−2 and long-term stability of 120 h at 100 mA cm−2. These results offer insights into the reaction mechanisms of HEM electrocatalysts and may guide future studies in designing high-entropy electrocatalysts with superior activity. Theoretical calculations guided the synthesis of np-NiFeCoMnOOH free-standing composite electrodes exhibiting strong LOM pathway selectivity in the OER process and scrutinizes the reaction pathway transition mechanism, which from AEM to LOM, and the source of excellent OER activity. [Display omitted] • Calculations validate the possibility and causes of pathway transformations of high-entropy OER catalysts. • Multiple active sites and two reaction pathways have been investigated. • np-NiFeCoMnOOH electrode exhibits a low overpotential of 194 mV at 10 mA cm−2 and long-term stability of 120 h at 100 mA cm−2. [ABSTRACT FROM AUTHOR]

In this study, the influence of different aging temperatures on the tensile ductility and Intergranular Corrosion (IGC) performance was investigated by using SEM, TEM, U2-net, DL-EPR, and EIS. The U2-net was employed for efficient and accurate identification of the Laves phase in the alloy 625. In parallel, an extensive analysis was conducted to assess the influence of Laves phase precipitation on the tensile ductility of the alloy. Additionally, an investigation into the precipitated phase was undertaken to explore the correlation between tensile ductility and IGC. The research findings indicate that with increasing aging temperature (from 873 K to 993 K), the elongation initially slightly increases, then sharply decreases, and finally slightly increases again. Simultaneously, the sensitivity to Intergranular Corrosion first increases and then slightly decreases. Additionally, the trained U2-Net achieved an average accuracy rate of 99.3% on the validation dataset, demonstrating that deep learning networks can effectively and rapidly identify Laves phases in SEM images. DL-EPR results reveal a certain correlation between high Ra values and low elongation. [Display omitted] • Innovative use of U2-net for efficient Laves phase identification in 625 alloy. • Quantitative study on Laves impact: model modifications reduce errors in assessing tensile toughness for 625 alloy. • DL-EPR reveals: low 625 alloy tensile toughness corresponds to high intergranular corrosion susceptibility. [ABSTRACT FROM AUTHOR]

The development of new catalysts is an urgent task in chemistry research because of the increasing demands for higher productivity and efficiency in modern industrial chemistry. High‐throughput (HT) technologies have emerged as powerful accelerators for the discovery of new catalytic materials. Generally, HT techniques involve HT computational screening of catalytic materials and HT experimental approaches. Significant progress has been made in discovering and optimizing catalysts, which demonstrates the speed and economic advantages of HT methods in a matter of process within days and even hours, in contrast with traditional time‐consuming trial and error experiments. From this perspective, the key processes of HT technologies for building a catalysts library are highlighted, including the virtual lab construction based on informatics tools and experimental data lab involving the following processes: 1) design of experiments; 2) reactants prepared manually or automatically; 3) constructing reactor that can well control the variations including materials diversity and reaction conditions (e.g., temperature and reaction time); 4) parallel characterization of fabricated catalysts. Moreover, the correlation between virtual lab and experimental data is discussed to inspire explorations in this field. Furthermore, several remaining challenges of HT technologies accompanied by possible research directions are presented to promote efforts in catalysts library creation. [ABSTRACT FROM AUTHOR]

Purpose: Nickel-aluminum bronze (NAB) has been widely used in ship propellers. It is always subjected to local micro-plastic deformation in service environments. This paper aims to study the influence of plastic deformation on the mechanical strength and corrosion resistance of NAB in 3.5 Wt.% NaCl solution. Design/methodology/approach: Scanning electron microscope and X-ray diffraction were used to analyze the microstructure of NAB alloy with different plastic deformations. Mechanical properties of the sample were measured by tensile experiment, and corrosion behavior was studied by electrochemical measurements and the long-term immersion corrosion test. Findings: Results showed that the plastic deformation caused lattice distortion but did not change the microstructure of NAB alloy. Microhardness and yield strength of NAB were significantly improved with the increase of deformation. The lattice distortion accelerated the formation of corrosion product film, which made the deformed alloy show a more positive open-circuit potential and an increased Rp. However, during the long-term immersion corrosion, the corrosion resistance of NAB alloys deteriorated with the increase of plastic deformation. This is because larger plastic deformation brought about higher internal stress in corrosion product film, which resulted in the premature peeling of the film and the loss of its protective effect on the alloy substrate. Originality/value: Tensile plastic deformations were found to cause a decline in the corrosion resistance of NAB. And the mechanism was clarified from the evolution of corrosion products during the corrosion process. [ABSTRACT FROM AUTHOR]

Abstract: In electroless copper plating baths using hypophosphite as the reducing agent, nickel ions was used to catalyze hypophosphite oxidation. However, the color of the copper deposits was dark or brown and the electrical resistivity was much higher than that obtained from formaldehyde baths. Polyethylene glycol (PEG) and K4Fe(CN)6 were used to improve the microstructure and properties of copper deposits obtained from electroless copper plating bath using hypophosphite as the reducing agent. The effects of PEG concentration on the deposition rate, the microstructure, morphology and electrical resistivity of the copper deposits, and the electrochemical reactions of hypophosphite (oxidation) and cupric ion (reduction) were investigated. The traces of hydrogen escaping from the deposits surface disappeared and the color of the copper deposits changed from dark-brown to dark red when the PEG concentration was 1.67×10−5 M or more. The deposition rate increased and the electrical resistivity of the copper deposits decreased slightly with the addition of PEG to the plating solution. The electrical resistivity of copper deposits decreased to 2.85μΩ cm with 1.67×10−5 M PEG and 4.70×10−6 M K4Fe(CN)6 in the bath. Larger grain size and higher (220) plane orientation were obtained with the increase of PEG concentration in the bath. The electrochemical current–voltage results showed that PEG accelerated the catalytic oxidation of hypophosphite at active nickel sites and had little effect on the reduction reaction of cupric ions on the deposit surface by adsorption on the electrode. [Copyright &y& Elsevier]

Abstract: A new kind of immobilized trypsin reactor based on sub-micron skeletal polymer monolith has been developed. Covalent immobilization of trypsin on this support was performed using the epoxide functional groups in either a one- or a multi-step reaction. The proteolytic activity of the immobilized trypsin was measured by monitoring the formation of N-α-benzoyl-l-arginine (BA) which is the digestion product of a substrate N-α-benzoyl-l-arginine ethyl ester (BAEE). Results showed that the digestion speed was about 300 times faster than that performed in free solution. The performance of such an enzyme reactor was further demonstrated by digesting protein myoglobin. It has been found that the protein digestion could be achieved in 88s at 30°C, which is comparable to 24h digestion in solution at 37°C. Furthermore, the immobilized trypsin exhibits increased stability even after continuous use compared to that in free solution. The present monolithic enzyme-reactor provides a promising platform for the proteomic research. [Copyright &y& Elsevier]

Abstract: Continuous alumina coating on multi-walled carbon nanotubes (MWCNTs) was successfully prepared by a new method of chemical precipitation using aluminum nitrate and ammonia as starting materials. Structure and morphology of the alumina/multi-walled carbon nanotubes (Al2O3/MWCNTs) composites were characterized by transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), infrared spectra (IR), thermo gravimetric analysis (TG), differential thermal analysis (DTA) and N2 adsorption–desorption. The results show that polyvinyl alcohol (PVA) modification on the surface of MWCNTs contributes to form continuous alumina coating, γ-Al2O3 layers with thickness of 1–3nm cover the surface of MWCNTs and the original structure of MWCNTs is retained during the coating process. [Copyright &y& Elsevier]

Abstract: Alumina nanofibers were successfully synthesized in mercury media at room temperature. Structure and morphology of the nanofibers were characterized by TEM, EDX, FESEM, XRD, TG, DTA and N2 adsorption–desorption. The results show that the as-grown alumina nanofibers are amorphous, and have diameters of 5–15nm and lengths up to several micrometers. After calcinated at 850°C for 2h, the amorphous alumina nanofibers convert to γ-Al2O3 nanofibers. The mechanism for the growth of alumina nanofibers was discussed and a model representing the growth process was presented. During the process, mercury will be produced by metathesis reaction of HgCl2 and Al, Al atoms continuously dissolve into mercury and diffuse to amalgam/air interface, and then Al atoms react with oxygen and water in air, finally alumina nanofibers can be formed. [Copyright &y& Elsevier]

The tandem type permeable reactive barriers-like reactor recovers Pb(II), As(III) and Zn(II) from the lead–zinc mine wastewater by combining hierarchical partitions and three targeted adsorption mediums. The device exhibits high-efficient removal and selective recovery capabilities for metals, as well as widely applicable to various wastewater inflow conditions. [Display omitted] • A novel combined tandem permeable reactive barriers-like reactor was reported. • Heavy metals in mining wastewater are removed sequentially and high-efficiently. • Each metal can be recycled due to the selective adsorption of the reactor medium. • The combined reactor performs steadily and efficiently under practical conditions. The resource treatment of mine wastewater with low-concentrations heavy metal ions is desirable for the sustainability of the metallurgical industries, but is challenging. In this study, we developed a novel combined tandem type permeable reactive barriers-like (PRBs-like) technology with implanted targeted adsorbents to achieve the selective removal of metals from mining wastewater. In the continuous flow test, the PRBs-like enable the content of lead, arsenate and zinc ions in 790 mL of actual mine effluent to reach below the Chinese pollutant discharge standards for lead and zinc industries (GB2546-2010) within 6 h. The expected ability of the reactor benefits from the outstanding mass transfer of the three adsorbents, tannic acid based polymer (TABP), cerium oxide (CeO 2) and zero-valent iron (ZVI), with capacities of 116.6, 87.5 and 61.8 mg g−1 for lead, arsenic and zinc ions at an equilibration time of 20 min. Noteworthy, TABP features a strong affinity for lead, as well as CeO 2 for arsenate, which is favorable to the aggregation of a single species metal in the corresponding reaction partition. In addition, factors including different flow rates, pH and reaction media distances on the performance of PRBs-like were investigated, demonstrating excellent adaptability of the tandem reactor to the wastewater environment. And long-term experiments showed the high stability and efficiency of the operation of the reactor. The graded combined device and the targeted adsorbent were first integrated in this work to point out a high-efficiency pathway, which can recycle the heavy metals in mine wastewater. [ABSTRACT FROM AUTHOR]

The tandem type permeable reactive barriers-like reactor recovers Pb(II), As(III) and Zn(II) from the lead–zinc mine wastewater by combining hierarchical partitions and three targeted adsorption mediums. The device exhibits high-efficient removal and selective recovery capabilities for metals, as well as widely applicable to various wastewater inflow conditions. [Display omitted] • A novel combined tandem permeable reactive barriers-like reactor was reported. • Heavy metals in mining wastewater are removed sequentially and high-efficiently. • Each metal can be recycled due to the selective adsorption of the reactor medium. • The combined reactor performs steadily and efficiently under practical conditions. The resource treatment of mine wastewater with low-concentrations heavy metal ions is desirable for the sustainability of the metallurgical industries, but is challenging. In this study, we developed a novel combined tandem type permeable reactive barriers-like (PRBs-like) technology with implanted targeted adsorbents to achieve the selective removal of metals from mining wastewater. In the continuous flow test, the PRBs-like enable the content of lead, arsenate and zinc ions in 790 mL of actual mine effluent to reach below the Chinese pollutant discharge standards for lead and zinc industries (GB2546-2010) within 6 h. The expected ability of the reactor benefits from the outstanding mass transfer of the three adsorbents, tannic acid based polymer (TABP), cerium oxide (CeO 2) and zero-valent iron (ZVI), with capacities of 116.6, 87.5 and 61.8 mg g−1 for lead, arsenic and zinc ions at an equilibration time of 20 min. Noteworthy, TABP features a strong affinity for lead, as well as CeO 2 for arsenate, which is favorable to the aggregation of a single species metal in the corresponding reaction partition. In addition, factors including different flow rates, pH and reaction media distances on the performance of PRBs-like were investigated, demonstrating excellent adaptability of the tandem reactor to the wastewater environment. And long-term experiments showed the high stability and efficiency of the operation of the reactor. The graded combined device and the targeted adsorbent were first integrated in this work to point out a high-efficiency pathway, which can recycle the heavy metals in mine wastewater. [ABSTRACT FROM AUTHOR]

Abstract: Ni–graphite composites were prepared by electroforming technology in a nickel sulphamate solution with graphite particles in suspension. The influence of graphite content, load and rotating speed on the properties of friction and wear was studied. The study indicates that wear resistance is improved to a critical value as graphite content increases, and then becomes worse. Both friction coefficient and wear mass loss increase with increasing load and rotating speed. The mechanism is transferred from abrasive wear for pure Ni to delaminating wear for Ni-graphite composites. [Copyright &y& Elsevier]

Abstract: Ni–SiC metal matrix composites with two kinds of SiC content were prepared by electroforming in a nickel sulphamate bath. Tensile strength and microstructure of the composites before and after heat treatment were investigated. The maximum of tensile strength was obtained after heat treatment at 300 °C×24 h. The values were 641 N/mm2 and 701 N/mm2 respectively. The complete reaction between nickel and SiC particles can produce shrinkage pores in the interface. The volume of shrinkage pores was equal to 8% of the volume of SiC particles in the composites. The interfacial reaction products were composed of Ni3Si and a little amount of Ni31Si12 after heat treatment at 600 °C×24 h. The fracture evolution went though microcracks initiation, growth and coalescence. Cracking of the matrix, debonding of Ni–SiC interfaces and cracking of particles were three types of cracking modes for Ni–SiC composites. [Copyright &y& Elsevier]

Rational design of bifunctional efficient electrocatalysts for both oxygen reduction (ORR) and oxygen evolution reactions (OER) is desirable—while highly challenging—for development of rechargeable metal–air batteries. Herein, an efficient bifunctional electrocatalyst is designed and fabricated by encapsulating Co nanoparticles in interconnected N‐doped hollow porous carbon nanofibers (designated as Co@N‐C/PCNF) using an ultrafast high‐temperature shock technology. Benefiting from the synergistic effect and intrinsic activity of the CoNC moiety, as well as porous structure of carbon nanofibers, the Co@N‐C/PCNF composite shows high bifunctional electrocatalytic activities for both OER (289 mV at 10 mA cm−2) and ORR (half‐wave potential of 0.85 V). The CoNC moiety in the composite can modulate the local environmental and electrical structure of the catalysts, thus optimizing the adsorption/desorption kinetics and decreasing the reaction barriers for promoting the reversible oxygen electrocatalysis. Co@N‐C/PCNF‐based aqueous Zn–air batteries (AZAB) provide high power density of 292 mW cm−2, and the assembled flexible ZAB can power wearable devices. [ABSTRACT FROM AUTHOR]

Graph Neural Networks (GNNs), such as GCN, GraphSAGE, GAT, and SGC, have achieved state-of-the-art performance on a wide range of graph-based tasks. These models all use a technique called neighborhood aggregation, in which the embedding of each node is updated by aggregating the embeddings of its neighbors. However, not all information aggregated from neighbors is beneficial. In some cases, a portion of the neighbor information may be harmful to the downstream tasks. For the high-quality aggregation of beneficial information, we propose a flexible method EGAI (Enhancing Graph neural networks by a high-quality Aggregation of beneficial Information). The core concept of this method is to filter out the redundant and harmful information by removing specific edges during each training epoch. The practical and theoretical motivations, considerations, and strategies related to this method are discussed in detail. EGAI is a general method that can be combined with many backbone models (e.g., GCN, GraphSAGE, GAT, and SGC) to enhance their performance in the node classification task. In addition, EGAI reduces the convergence speed of over-smoothing that occurs when models are deepened. Extensive experiments on three real-world networks demonstrate that EGAI indeed improves the performance for both shallow and deep GNN models, and to some extent, mitigates over-smoothing. The code is available at https://github.com/liucoo/egai. [ABSTRACT FROM AUTHOR]

With the low redox potential of −3.04 V (vs SHE) and ultrahigh theoretical capacity of 3862 mAh g−1, lithium metal has been considered as promising anode material. However, lithium metal battery has ever suffered a trough in the past few decades due to its safety issues. Over the years, the limited energy density of the lithium‐ion battery cannot meet the growing demands of the advanced energy storage devices. Therefore, lithium metal anodes receive renewed attention, which have the potential to achieve high‐energy batteries. In this review, the history of the lithium anode is reviewed first. Then the failure mechanism of the lithium anode is analyzed, including dendrite, dead lithium, corrosion, and volume expansion of the lithium anode. Further, the strategies to alleviate the lithium anode issues in recent years are discussed emphatically. Eventually, remaining challenges of these strategies and possible research directions of lithium‐anode modification are presented to inspire innovation of lithium anode. [ABSTRACT FROM AUTHOR]

Recently, magnetic metal-semiconductor nanocomposite films with a uniform superparamagnetic structure have attracted increasing interest in negative magnetoresistance (MR) properties at room temperature (RT). In this work, we have designed and prepared an original nonuniform structure with coexistence of size-distributed ferromagnetic Co clusters and superparamagnetic Co particles in Co–ZnO nanocomposite films, with Co content between 41 and 65 at.%. The film with 49 at.% Co shows a large RT negative MR with a maximum value of over 9.5%. As Co content increasing, the ferromagnetic Co clusters grow both in quantity and size. Meanwhile, the curves of normalized MR become broader, and the peaks of the normalized MR field sensitivity (FS) shift to higher fields. It is noteworthy that the increase in ferromagnetic Co clusters can effectively modulate the MR FS, which is reasonably explained by establishing a mechanism model with the localized magnetization flux effect and inhomogeneous current paths based on size-distributed ferromagnetic Co clusters. This nonuniform structure can be extended to other nanocomposite materials for the modulation of MR FS by microstructure control in various application scenarios. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to study the effect of temperature on the process and kinetic parameters of the hydrogen evolution reaction of X80 under cathodic protection (CP) in 3.5% NaCl solution. Design/methodology/approach: Potentiodynamic polarization combined with the hydrogen permeation test is used to analyze the hydrogen evolution reaction (HER) process and the rate-determining step for which is diagnosed through the electrochemical impedance spectrum method. Then, the influence of temperature on kinetic parameters of HER can be known from the results obtained by using the Iver-Pickering-Zamenzadeh model for data analysis. Findings: The results show that the HER proceeds through Volmer–Tafel route with the Volmer reaction acting as the rate-controlling step; Increasing temperature gives a higher activity of the HER on X80, it also accelerates the hydrogen desorption and diffusion of hydrogen into the metal. Originality/value: There exist few studies on the topic of how temperature affects the HER process. It is imperative to conduct a relevant study to give some instruction in cathodic protection system design and this paper fulfills this need. [ABSTRACT FROM AUTHOR]

• The Fe 3 O 4 @ZnAlCe-MoO 4 -LDHs composite was synthesized by co-precipitation method. • The composite possesses soluble Cl−/magnetic field responsive properties. • The composite has high corrosion inhibition efficiency for Q235 steel. • The nanovehicle Fe 3 O 4 @ZnAlCe-MoO 4 -LDHs can be regenerated and recycled. A novel dual-stimuli-responsive inhibitor nanovehicle Fe 3 O 4 @ZnAlCe-MoO 4 -LDHs was synthesized via a facile double-drop co-precipitation method. The obtained Fe 3 O 4 @ZnAlCe-MoO 4 -LDHs presents well-defined hierarchical core–shell structure with MoO 4 2− corrosion inhibitor intercalated lamellar ZnAlCe-LDHs nanocrystals of ~30 nm assembling closely to Fe 3 O 4 microspheres surface, possessing moderate inhibitor loading of 9.72% and strong superparamagnetism. The release results reveal that in the same NaCl solution, the rel eq (equilibrium release amount, 49.1%) and t 0.5 (the time for release fraction of 50%, 4.5 h) were delayed much by magnetic field relative to non-magnetic field case (51.6%, 2.5 h). And the rel eq decreased with magnetic field strength, accompanied by the prolongation of t 0.5 , up to 6 h under a 1350 Gs magnet. Similarly, with keeping the magnetic field unvaried, the decline of NaCl solution concentration led to lower rel eq and longer t 0.5. The kinetic fittings displayed that for all cases, the release process is inclusive of interlayer diffusion between LDHs layers (path I), interparticle diffusion among stacked LDHs crystals (path II) and diffusion between magnetic nanoparticles (path III). Compared to non-magnetic field, diffusion difficulties of path III was greatly enhanced under magnetic field. While for low-Cl− concentration system, the path I were limited effectively. Thus these two stimulus response factors can be used to regulate release behavior. Meanwhile, the protection efficiency of the nanovehicle for Q235 steel is higher than 88% because of the formation of inhibition film (ferrous or iron molybdate and hydroxide of zinc and cerium) on Q235 surface and the reduction of Cl− concentration in the solution via ion exchange. Moreover, the nanovehicle, presenting outstanding structural and magnetic stabilities, can be regenerated by a series of experiments, owning appreciable recycling performance and good anticorrosion activity in six recycles. [ABSTRACT FROM AUTHOR]

The hollow Fe 3 O 4 microspheres were firstly synthesized by solvothermal method. And then Fe 3 O 4 /MBT nanocomposite inhibitor was obtained by loading 2-mercaptobenzothiazole (MBT) inhibitor under negative vacuum impregnation treatment and characterized using transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, nitrogen adsorption-desorption isotherms and vibrating sample magnetometer. The release behavior of MBT and inhibition behavior of Fe 3 O 4 /MBT nanocomposite under different magnetic field (MF) strength were evaluated by UV–vis spectroscopy, electrochemical techniques and immersion tests. The results show that the synthesized superparamagnetic Fe 3 O 4 /MBT nanocomposite shows high MBT loading capacity of 55.4 %. Under the application of MF, the release behavior of MBT from Fe 3 O 4 /MBT is dominated by Fickian diffusion and diffusion among magnetic nanoparticles, and the release rate and inhibition efficiency are less than that of without MF under the same release time. The nanocomposite has a good inhibition effect for carbon steel in NaCl solution with maximum inhibition efficiency of 95.7 %, and also possesses excellent recycling stability with loading capacity of 45.1 % and inhibition efficiency of 78.8 % after five cycles. [ABSTRACT FROM AUTHOR]

Tuning the electronic states near the Fermi level can effectively facilitate the reaction kinetics. However, elucidating the role of a specific electronic state of metal oxide in simultaneously regulating the CO2 electroreduction reaction (CO2RR) and competing hydrogen evolution reaction (HER) is still rare, making it difficult to accurately predict the practical CO2RR performance. Herein, replacing the Zn site by heteroatoms with different outer electrons (Mo and Cu) is found to tune both occupied and unoccupied orbitals near the Fermi level of ZnO. Moreover, the different electronic states significantly modulate both CO2RR and HER activity with a totally inverse trend, thus dramatically tuning the practical CO2RR performance. In parallel, the correlation between electronic states, reaction free energies and practical activity is demonstrated. This work provides a possibility for engineering efficient CO2RR eletrocatalysts through tunable composition and electronic structures. [ABSTRACT FROM AUTHOR]