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[Display omitted] The use of low-cost and effective cocatalyst is a potential strategy to optimize the effectiveness of photoelectrochemical (PEC) water splitting. In this study, tungsten phosphide (WP) is introduced as a remarkably active cocatalyst to enhance the PEC efficiency of a Bi 2 WO 6 photoanode. The onset potential of Bi 2 WO 6 /WP demonstrates a negative shift, while the photocurrent density demonstrates a significant 5.5-fold increase compared to that of unmodified Bi 2 WO 6 at 1.23 V RHE (reversible hydrogen electrode). The loading of WP cocatalyst facilitates the rapid transfer of holes, increasing the range of visible light absorption, the water adsorption ability as well as promoting the separation of photogenerated electrons and holes via the built-in electric field between Bi 2 WO 6 and WP. This study proposes a strategy to hinder the recombination of electron-hole pairs by using WP cocatalyst as a hole capture agent, improve the photoelectric conversion efficiency, and enhance the overall photoelectrochemical properties of Bi 2 WO 6 photoanode. [ABSTRACT FROM AUTHOR]

Aging and thermal runaway are two significant reasons why lithium-ion batteries are struggling to become more widely available. Aging at different temperatures causes differences in the aging mechanism and thermal runaway behaviour of lithium-ion batteries. In this paper, four sets of commercial lithium-ion batteries are aged at 25 °C, 40 °C, 60 °C and 80 °C respectively for 100 cycles. Then the morphology and composition of the electrodes and separators are analysed in order to reveal the mechanism of changes in electrical performance and thermal stability due to aging at different temperatures. The differences in the decomposition products of the solid electrolyte intermediate (SEI) layer are an important factor in inducing changes in thermal runaway behaviour. At 60 °C, the accumulation of SEI decomposition products results in thicker SEI layers and shorter thermal runaway times. At 80 °C, the SEI decomposition products are heavily transformed into particles with a loose structure, generating a large amount of gas in the process, which further leads to the rupture of the aluminium-plastic film and the evaporation of the electrolyte, with a longer duration of thermal runaway and a lower maximum temperature. [Display omitted] [ABSTRACT FROM AUTHOR]

The interfacial bonding strength of Ti/steel clad plates is a crucial factor that affects their application. However, the effect of the surface state, which is a significant determinant, is often neglected. In this study, various surface treatment processes were employed to create different surface states based on the hot-rolling of double-layer steel billets, and the effects and mechanisms of these surface states on the bonding performance of hot-rolled Ti/steel clad plates were systematically examined. The results showed that the Ti/steel clad plates pretreated with a louver wheel exhibited the highest bonding performance, with the average bonding strength peaking at 328.67 MPa and stabilising at approximately 300 MPa. This strength was approximately 50 % greater than that achieved with wire brush treatment and significantly surpassed the results obtained with sanding belts and diamond grinding discs. The analysis of the surface properties and microstructural characteristics revealed that various surface treatments led to different levels of work hardening and lattice distortion at the surface, and the interface bonding strength depended on the degree of matching between these factors. Proper surface hardening can promote the transformation of lattice distortion energy into a diffusion-driving force of elements on both sides of the interface during rolling, enabling sufficient diffusion of elements on both sides of the interface and obtaining good interface bonding performance. A phenomenological prediction mechanism-based model was established to quantify the relationship between the surface state and the bonding strength. This study elucidats the mechanism by which the surface state of materials influences the interfacial bonding performance of hot-rolled Ti/steel clad plates. These findings have significant implications for enhancing the interfacial properties of these composite plates and for selecting suitable pre-rolling surface treatment processes. [Display omitted] • This work studied the effect of surface states during the rolling compounding process. • The appropriate surface pretreatment process for rolling Ti-steel clad plates was identified and verified. • Surface pretreatment led to surface hardening and the accumulation of lattice distortions. • The interfacial bonding mechanism of hot-rolled Ti-steel clad plates based on surface states was elucidated. • A lattice distortion energy-hardening-diffusion based phenomenological model was proposed. [ABSTRACT FROM AUTHOR]

Thermal runaway (TR) of Li-ion batteries (LIBs) presents a disastrous safety hazard and a significant barrier to the wider adoption of electric vehicles (EVs). Internal short circuit (ISC) induced by mechanical abuse is one of the causes of battery TR. This paper uses hemispherical indentation tests to trigger ISC in the battery at different temperatures and studies the battery deformation and fracture mode. Results show as the initial temperature increases, the battery hardness and strength decrease, and the fracture mode of the laminar structure changes from shear fracture to localized rupture. In the shear fracture mode, the ISC homogeneously heats the battery, and it does not directly trigger TR. In the localized rupture mode, the ISC is only induced at the layers close to the indenter and generates a hot spot exceeding 200 °C, leading to the initiation of TR. Therefore, the mechanical properties of batteries under different conditions need to be studied in more detail to develop batteries that are safer under mechanical abuse. • Three deformation phases: Compaction and plasticity, destabilization, and collapse. • The hardness and strength of the battery decrease as the temperature increases. • The deformation is concentrated locally at higher temperatures. • Shear fracture at low temperatures and localized rupture at high temperatures. • Shear fracture causes gradual heating, and localized rupture directly triggers TR. [ABSTRACT FROM AUTHOR]

When lithium-ion batteries (LIBs) are subjected to thermal, electrical, or mechanical abuse during use or transport, thermal runaway may occur, which can result in fire and explosion. Fine water mist has attracted considerable attention as an efficient, environmentally friendly fire extinguishing medium. We used fine water mist containing a compound additive to suppress the TR of LIBs and studied the effect of different types of additives at various concentrations on TR. The compound additive consisted of urea, fatty alcohol polyoxyethylene ether (AEO-9), nonionic fluorine surfactant (FC-4430), and dimethyl methylphosphonate (DMMP). The optimal concentration of each component was obtained. An orthogonal experiment based on these optimal concentrations was conducted to determine the additive with the strongest inhibition effect. Fine water mist with this low conductivity compound additive can inhibit TR effectively and reduce the short-circuit damage of batteries without TR caused by water immersion. [ABSTRACT FROM AUTHOR]

Bismuth ferrite (BiFeO 3) holds great potentials in the photoelectrocatalysis due to the advantages of low cost, narrow band gap and good chemical stability. However, the photoelectrochemical performance of BiFeO 3 is usually inhibited by the poor charge carrier transport. Here, we report the flame annealing synthesized Sm3+ doped BiFeO 3 photocathodes for efficient hydrogen production. Greatly enhanced water reduction activity was found in doped samples. The Bi 0.95 Sm 0.05 FeO 3 composition exhibited largest photocurrent density of 0.1061 mA cm−2 at 0 V vs. RHE in 0.5 M Na 2 SO 4 , which was 5.6 times higher than that of the pristine BiFeO 3. Mott-Schottky analysis and electrochemical impedance spectra proved that the Bi3+substitution increased the charge carrier concentration and facilitated the charge migration. Incident photon-to-electron conversion efficiency (IPCE) value for Bi 0.95 Sm 0.05 FeO 3 film (∼6.39% at 325 nm) was approximately ten times higher than that of undoped sample. The high performance can be ascribed to the rational Sm3+ doping, which can improve visible light absorption ability, facilitate the charge carrier transport kinetics and hinder the recombination of photogenerated carriers. Our work provides a facile cation doping with rare earth ions to improve the photoelectrochemical performances. [ABSTRACT FROM AUTHOR]

The thermal runaway (TR) of lithium-ion batteries (LIBs) hinders the development of new energy vehicles (NEVs) because its extrusion-state characteristics remain unclear. Here, 100% state of charge (SOC) pouch LIBs are heated under extrusion, for triggering TR. The battery temperature, voltage, and deformation during the TR are recorded, and a high-speed infrared camera is used along with a high-definition camera for capturing the TR's flame evolution process. The battery thickness gradually decreases with increasing the temperature of a squeezed-state battery, until dropping abruptly at the TR onset. In the squeezed state, smoke is produced for a shorter time, the TR jet intensity significantly increases, and the wreckage exhibits a tight block structure. The TR onset occurs faster for higher squeezing pressures, the jet fire duration is shorter, while the flame temperature and area increase. The maximal temperature of the battery surface increases first and then drops, and the mechanism of the TR gradually changes from heating to internal circuit shorting. For squeezing pressures under 5000 N, the TR onset temperature increases slightly compare with the non-squeezed state, and then decreases to approximately 100 °C as the pressure approaches 5000 N. [Display omitted] • Heating the battery in a squeezed state causes thermal runaway (TR). • The initial temperature of the TR under the squeeze state is reduced. • The TR in the squeezed state is accompanied by violent injection. • The danger of the battery TR in a squeezed state increase. [ABSTRACT FROM AUTHOR]

As the core of blockchain technology, the consensus mechanism ensures the safe and stable operation of the blockchain system. According to the more complex traceability of data when sharing cross-system and cross-chain, the paper proposes the Layered Cross-Chain Practical Byzantine Fault Tolerance (LC-PBFT) suitable for cross-chain scenarios to ensure the secure traceability of data in the process of cross-chain data traceability. Firstly, in a single chain, the initial reputation value is set according to the success rate and efficiency of the nodes in the historical transactions in the chain, the reputation ranking of the nodes in the chain is realized by the improved PageRank algorithm, and delegated nodes are selected to participate in the cross-chain consensus based on reputation ranking. Then, the forest topology is sorted according to the contribution of the consensus nodes in the cross-chain system, and the consensus results from the child nodes are quickly verified by aggregation signature, which prevents the parent node from tampering with the consensus results of the child nodes. Meanwhile, the consensus process between the sibling nodes in the same layer and the view switching protocol when the master node fails are given. Finally, the performance of the LC-PBFT consensus algorithm is analyzed, and its advantages in performance such as throughput are verified by simulation. Compared with the Practical Byzantine Fault Tolerance (PBFT) algorithm, the consensus latency of the LC-PBFT consensus algorithm is reduced by 50.17%, and the throughput is improved by 19.37%. [ABSTRACT FROM AUTHOR]

We establish an attractor bifurcation theorem and prove a global dynamic bifurcation theorem for positive solutions of evolution equations in ordered Banach spaces. These results may give a new insight into some fundamental problems in mathematical biology such as the persistence and the reproducing numbers of species. [ABSTRACT FROM AUTHOR]

• Primary aging mechanism changes from "dead lithium" to SEI growth at low temperature. • "Dead lithium" causes more capacity fading than SEI growth at low temperature cycle. • Plated lithium is inhomogeneity during long low temperature cycle. • Plated lithium is consumed at high temperature cycle after low temperature cycle. • Charge current affects battery aging at high temperature after low temperature most. Lithium plating is an important issue for lithium-ion battery safety and cycle life that can be caused by cycle at low temperature. In this study, we investigated battery aging over an extended low-temperature cycle and at high temperature after the low-temperature cycle. Nondestructive and destructive analysis methods were used to study battery electrochemical dynamics and changes to the materials, and the results indicated that battery aging over the extended low-temperature cycle could be divided into two stages. The mechanism of the first stage is that of "dead lithium," which causes significant capacity fading, whereas that of the second stage is solid electrolyte interphase (SEI) growth. It was also found that plated lithium accelerates battery aging at high temperature; part of it is intercalated into anode, another part of it reacts with the electrolyte, thus consuming the plated lithium. Thus, electrolyte decomposition and SEI growth are the primary aging mechanisms at high temperature after low-temperature cycling. The plated lithium content and charge/discharge rate affected plated lithium consumption during the high-temperature cycle. Plated lithium was not depleted for the battery with significant amounts of plated lithium or upon charging with high current and discharging with both high and low current when the state of health (SOH) decreased to 70%. The factors affecting battery aging ranked in order of importance are charge current > plated lithium content > high temperature > discharge current. [Display omitted] [ABSTRACT FROM AUTHOR]

Thermal runaway (TR) propagation of lithium-ion batteries (LIBs) in air may cause fire, and argon can effectively inhibit LIBs with TR propagation. The oxygen concentration and gas flow rate are the important factors affecting the TR propagation. Hence, an experimental device for LIBs with TR propagation in air and argon environments in a confined space was established, and a series of experiments were carried out. Subsequently, the critical conditions of oxygen concentration and gas flow rate that inhibit the TR propagation of the cell are investigated. The study found that LIBs with TR propagation occur in an air environment, while argon gas has a good effect on inhibiting LIBs with TR propagation. The critical oxygen concentration for LIBs with TR propagation in an argon environment is between 2.5 and 5%. The critical gas flow rates for LIBs with TR propagation are greater than 24 L min−1 under air and are between 18 and 24 L min−1 under argon. It is firmly believed that this work can provide useful inspirations for the TR suppression of LIBs. [ABSTRACT FROM AUTHOR]

• BiFeO 3 /Bi 2 O 3 composite was successfully fabricated by a facile flame annealing. • The formation of Bi 2 O 3 improves the PEC performance. • The maximum photocurrent of BiFeO 3 /Bi 2 O 3 is two times larger than BiFeO 3. • High PEC performance was attributed to improved light absorption and active sites. BiFeO 3 -based ferroelectrics are promising photoelectrodes for photoelectrochemical (PEC) water splitting. To further enhance its photoelectrocatalytic activity, BiFeO 3 /Bi 2 O 3 composite is designed by a simple and cost-effective flame annealing process in this work. The obtained BiFeO 3 /Bi 2 O 3 photocathode achieves a photocurrent density of −0.21 mA/cm−2 at 0.38 V RHE , with a 160 mV positive shift of the onset potential. Furthermore, the photon-to-current efficiency of BiFeO 3 /Bi 2 O 3 displays an obvious enhancement. The improved PEC performance is due to the formation of composite, which reduces the recombination of carriers, promotes interfacial charge transfer and provides more active sites. Our work provides a promising approach to improve the performance of ferroelectric photoelectrodes. [ABSTRACT FROM AUTHOR]

Abstract: In this study, the performance and exhaust emissions of diesel engine fueled with diesel from direct coal liquefaction (DDCL)–biodiesel blends consisting of 0%, 20% and 40% biodiesel are investigated. In order to decrease nitric oxides (NOX) and soot emissions, retarded injection and cooled exhaust gas recirculation (EGR) strategies are introduced. Experiments are conducted on a four-cylinder, four-stroke, direct injected diesel engine without any modification. It is found that compared with pure DDCL, DDCL–biodiesel blends can reduce maximum pressure rise rate and gain lower combustion noise and mechanical load of diesel engine. In addition, there is hardly any difference for combustion phase between test fuels. Both exhaust emissions and fuel consumption are reduced due to the improved combustion by fuel properties of biodiesel, such as cetane number and fuel oxygen. When EGR rate is increased to 40%, with an increment of biodiesel in blends, NOX, carbon monoxide (CO) and equivalent brake specific fuel consumption (BSFC) are still decreased, and soot emission is increased. Anyway, both exhaust emissions and equivalent fuel consumption are controlled to a quite low level under retarded injection for DDCL–biodiesel blends. [Copyright &y& Elsevier]

Highlights: [•] Diesel from direct coal liquefaction was studied on a common rail diesel engine. [•] Multiple-injection was introduced to decrease NOX and soot emissions. [•] Retarded main injection can reduce combustion noise and NOX, and causes a soot hump. [•] Injection strategy should be calibrated carefully to reduce NOX and soot. [ABSTRACT FROM AUTHOR]

In response to the local path planning issue encountered by Autonomous Underwater Vehicle (AUV) during autonomous navigation when facing sudden threats or obstacles, a rapid path planning repair solution based on the IRRT*-VSRP method is proposed in this paper. This method combines an enhanced RRT* algorithm with a threat-based variable step-size receding horizon predictive strategy, effectively reducing the search space in three-dimensional environments. Its notable features include rapid local path repair and generation, thereby improving the success rate and efficiency of planning. Simulation results demonstrate that the IRRT*-VSRP algorithm significantly reduces the time required for planning repair and enhances the directionality of tree expansion, rendering it suitable for complex underwater three-dimensional environments and enhancing the efficiency of AUV planning repair. [ABSTRACT FROM AUTHOR]

In this study, oxygen vacancies were introduced into the hematite (α-Fe 2 O 3) photoanode via a simple and rapid butane flame annealing method. The presence of oxygen vacancies were demonstrated by high-resolution transmission electron microscopy (HRTEM), electron paramagnetic resonance (EPR) and X-ray photoelectron spectroscopy (XPS). The photocurrent density of optimum α-Fe 2 O 3 electrodes was 0.67 mA cm-2 at 1.23 V RHE , about 2.7 times higher than that of N 2 annealed electrode. Our study showed that butane flame annealing process can introduce oxygen vacancies defects in Fe 2 O 3 electrodes, which would improve carrier transfer efficiency, increase electron density, enhance water oxidation activity, and narrow the light optical bandgap. The use of butane flame annealing is a simple and effective strategy to enhance the PEC performance of hematite thin films. • Fe 2 O 3 photoanodes with oxygen vacancies were successfully synthesized through butane flame annealing. • Oxygen vacancies can improve charge transfer efficiency and increase the utilization rate of photogenerated holes at the interface. • The method of annealing with butane flame is simple and time-saving. • The FA-Fe 2 O 3 electrode achievs a light current density of 0.67 mA cm-2 at 1.23 V RHE. [ABSTRACT FROM AUTHOR]