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HMF is converted into high-value-added FDCA with NiSeO3@(CoSeO3)4heterojunction catalyst linking to H2production via Co-Ni paired site.

Energy storage devices are the hub of a multi-energy complementary distributed energy system. Hydrated salts are the most suitable phase change material for energy storage devices, but subcooling is the main obstacle to their application. Nucleation requires a driving force so the use of nucleating agents alone does not reduce subcooling to a very low level. To address this issue, this paper first screened nucleating agents and then further reduced the subcooling of sodium acetate trihydrate in conjunction with stirring or direct current. The effects of rotor mass, rotational speed, direct current voltage, and electrode material on nucleation were analyzed. Finally, the stability of the composite phase change material in the presence of simultaneous stirring and energization was analyzed. The results showed that the addition of 1.5% in weight of disodium hydrogen phosphate dodecahydrate to sodium acetate trihydrate can reduce the subcooling to about 2.3°C. Continued addition of stirring or electricity can reduce the subcooling of sodium acetate trihydrate to within 0.5°C or even eliminate it. The higher the momentum of the stirring, the better the improvement in subcooling, phase separation, and thermal conductivity. The higher the direct current voltage, the better the nucleation effect, but the electrode life will be lower. The silver electrode has the best nucleation effect. No new material was produced in the solution after 100 cycles in the presence of both stirring and direct current. The melting point of the phase change material was increased by 0.2°C and the latent heat value decreased by 1.8%, still with good stability. The trace of deionized water should be added to the phase change material in subsequent studies to compensate for the consumption of water by the anodic elution.

In this study, we investigate the existence and stability of in-phase and out-of-phase dissipative solitons in a dual-waveguide lattice with linear localized gain and nonlinear losses under both focusing and defocusing nonlinearities. Numerical results reveal that both types of dissipative solitons bifurcate from the linear amplified modes, and their nonlinear propagation constant changes to a real value when nonlinearity, linear localized gain, and nonlinear losses coexist. We find that increasing the linear gain coefficient leads to an increase in the power and propagation constant of both types of dissipative solitons. For defocusing nonlinearity, in-phase solitons are stable across their entire existence region, while focusing nonlinearity confines them to a small stable region near the lower cutoff value in the propagation constant. In contrast, out-of-phase solitons have a significantly larger stable region under focusing nonlinearity compared to defocusing nonlinearity. The stability regions of both types of dissipative solitons increase with increasing nonlinear losses coefficient. Additionally, we validate the results of linear stability analysis for dissipative solitons using propagation simulations, showing perfect agreement between the two methods.

The effect of final rolling temperature ranging from 962 to 696 °C on as-rolled high-Mn austenitic low-temperature steel was investigated using scanning electron microscopy, electron backscatter diffraction, transmission electron microscopy, and X-ray diffraction. The microstructure of the experimental steel remained austenite without suffering ferrite phase transformation, even when produced with a final rolling temperature as low as 696 °C. A decrease in the final rolling temperature of the steel was accompanied by a decrease in grain size from 20.2 to 6.0 μm, accompanied by an increase in dislocation density from 3.01 × 1014to 10.9 × 1014 m−2. In addition, M23C6carbides precipitated at the grain boundaries when the final rolling temperature was below 782 °C. Grain refinement and increased dislocation density significantly enhanced the strength of the material. However, an increase in the intragranular dislocation density compromised grain deformation ability. Moreover, the precipitation of M23C6reduced the plasticity and toughness of the material. Considering the balance between yield strength and low-temperature toughness, the optimal final rolling temperature was 898 °C; this produced a material with a yield strength of approximately 507 MPa and a low-temperature impact energy absorption of approximately 143 J.

Antibiotics Prophylaxis to prevent capsular contracture in prosthesis-based breast surgery is common in clinical practice. However, there is currently a dearth of high-quality evidence concerning the effectiveness of antibiotic usage in this field. To identify all pertinent studies prior to January 2023, a comprehensive literature search was conducted in the PubMed, Embase, Web of Science, Cochrane Library, and Medline databases. The extracted data was then subjected to meta-analysis. Fourteen studies were retained in the analysis. According to the results, perioperative antibiotic prophylaxis did not reduce the risk of capsular contracture (RR 1.15, 95% CI 0.82–1.59, p= 0.55) or surgical-site infection (RD 0.01, 95% CI − 0.01 to 0.03, p= 0.59) compared to nonantibiotic prophylaxis. There was no statistically significant difference between extended antibiotic prophylaxis and perioperative antibiotic prophylaxis in terms of preventing capsular contracture, whether calculated by patient numbers (RD 0.01, 95% CI − 0.01 to 0.02, p= 0.87) or by total procedures (RD 0.00, 95% CI − 0.00 to 0.01, p= 0.88), or controlling surgical-site infection (RR 1.05, 95% CI 0.77–1.44, p= 0.27). Additionally, topical antibiotic irrigation did not decrease the risk of infection (RR 0.61, 95% CI 0.34–1.08, p= 0.29) and capsular contracture, regardless of patient number (RR 0.41, 95% CI 0.27–0.63, p= 0.18) or total number of procedures (RR 1.29, 95% CI 0.73–2.28, p< 0.01). Current evidence revealed that both systemic and topical antibiotic prophylaxis may not provide benefits in preventing capsular contracture in prosthesis-based breast surgery. When the occurrence of surgical-site infections is minimized to the greatest extent, the administration of additional antibiotics for reducing capsular contracture should be carefully and judiciously considered.

Shale reservoirs are characterized by an abundance of nanoscale porosities and microfractures. The states of fluid occurrence and flow behaviors within nanoconfined spaces necessitate novel research approaches, as traditional percolation mathematical models are inadequate for accurately depicting these phenomena. This study takes the Gulong shale reservoir in China as the subject of its research. Initially, the unique mixed wetting characteristics of the Gulong shale reservoir are examined and characterized using actual micropore images. Subsequently, the occurrence and flow behavior of oil within the nanoscale bedding fractures under various wettability scenarios are described through a combination of microscopic pore image and molecular dynamics simulations. Ultimately, a mathematical model is established that depicts the velocity distribution of oil and its apparent permeability. This study findings indicate that when the scale of the shale bedding fractures is less than 100 nm, the impact of the nanoconfinement effect is significant and cannot be overlooked. In this scenario, the state of oil occurrence and its flow behavior are influenced by the initial oil-wet surface area on the mixed wetting walls. The study quantifies the velocity and density distribution of oil in mixed wetting nanoscale shale bedding fractures through a mathematical model, providing a crucial theoretical basis for upscaling from the nanoscale to the macroscale.

ABSTRACTBackgroundThis study aimed to adopt the conventional signal detection methods to explore a new way of risk identification and to mine important drug risks from the perspective of big data based on Zhenjiang Adverse Event Reporting System (ZAERS).Research design and methodsData were extracted from ZAERS database between 2012 and 2022. The risks of all the reported drug event combinations were identified at the preferred term level and the standardized MedDRA query level using disproportionality analysis. Then, we conducted signal assessment according to the descriptions of drug labels.ResultsIn total 41,473 ADE were reported and there were 12 risky signals. Signal assessment indicates the suspected causal associations in clindamycin-taste and smell disorders, valsartan-hepatic enzyme increased and valsartan-edema peripheral; the specific manifestations of allergic reactions triggered by clindamycin, cefotaxime, cefazodime, ShexiangZhuanggu plaster, ShexiangZhuifeng plaster, and Yanhuning need to be refined in drug labels. In addition, the drug labels of NiuHuangShangQing tablet/capsule, Fuyanxiao capsule, and BiYanLing tablet should be improved.ConclusionsIn this study, we attempted a new way to find potential drug risks using small spontaneous reporting data. Our findings also suggested the need for more precise identification of allergic risks and the improvement of traditional Chinese medicine labels.

Conventional ocean wave observation instruments are powered by batteries, limiting the continuous observation time. Besides, the waste of batteries brings environmental contaminations. Triboelectric nanogenerators (TENGs) can reveal ocean wave information through their electrical output, taking the triboelectric charge as the information carrier. However, charge amplification is necessary, consuming additional energy. Herein, taking the photons rather than electrons as the information carrier, we developed a fully self-powered natural light-enabled sensing system for ocean wave monitoring by coupling two rotary-freestanding sliding TENGs (RFS-TENGs) and a polymer network liquid crystal (PNLC)-triggered optical system. The natural light is modulated by the PNLC driven by ocean wave-induced friction. With the assistance of a one-way bearing, the rise and fall of the wave will trigger different RFS-TENGs to power the PNLC in different voltage drops, leading to different transmitted natural light intensities. The wave height information can be obtained through the number of pulse signals with the same trough light intensity, while the wave period can be obtained through the duration between the same two sets of pulse signals. The effectiveness of the developed sensing paradigm in practical applications was verified by flume-based experiments, with the highest accuracies of 90.7% in wave height and 99.8% in wave period.

Reconfigurable intelligent surface (RIS) holds great promise as communication aid which is capable of controlling the electromagnetic propagation environment by adjusting the phase shift of reflective elements. However, in RIS-assisted multi-user wireless communication systems, channel estimation is challenging due to the inclusion of a large number of passive reflective elements within the RIS. To address this problem, we take advantage of the sparsity inherent in multi-user cascade channels and propose a novel cascade channel estimation strategy with low pilot overhead. Specifically, inspired by matrix vectorization and total variational regularization, we estimate the cascaded sparse channels by following Sparse Bayesian Learning (SBL) inference after vectorizing the channel matrix. By introducing regularization to virtual angle-domain sparse channel hyperparameter priors during hyperparameter updates, which penalize non-zero and zero regions of sparse channels differently, thereby enhance the sparseness objective exploited by SBL, this innovation results in a significant reduction in pilot overhead. We then perform SBL inference by updating hyperparameters in parallel using an Expectation-Maximization-based segment alternating optimization method. Simulation results demonstrate the effectiveness of our proposed algorithm that it can substantially reduce the pilot overhead.

ABSTRACTFor point clusters, the conflict and crowding of map symbols is an inevitable problem during the transition from large to small scales. The cartographic generalization involved in this problem as a spatial decision-making process is usually related to the analysis of spatial context, the choice of abstraction operators, and the judgment of the resulting data quality. The rules summarized by traditional generalization methods usually require manual setting of conditions or thresholds and sometimes encounter special cases that make it difficult to directly match certain rules or integrate different rules together. An alternative method is using a data-driven strategy under AI technology background to simulate cartographer behaviors through typical sample training, such as deep learning. The integration of cartography domain knowledge and deep learning is a better choice to settle generalization decisions. This study uses a combination of domain knowledge and a data-driven approach to introduce graph neural networks into point cluster generalization. First, we construct a virtual graph structure of point clusters using Delaunay triangulation, secondly, we extract spatial features, contextual features, and attributes of each point separately, and then propose a generalization model based on the TAGCN network. Finally, this model is trained with the manually generalized sample to realize the automatic point cluster generalization. The results demonstrate that the proposed model is valid and efficient for point cluster generalization and that this algorithm can better maintain various characteristics of the point cluster in both the local area and the overall map compared to other methods.

Change detection (CD) is an increasingly popular research direction in the field of remote sensing (RS). With the rapid development of RS, the resolution of RS images is gradually improving, which also puts forward higher requirements for the generalization ability of CD models. Due to its excellent feature extraction capabilities, convolutional neural networks (CNNs) have achieved great success in CD tasks in the past. However, CNN cannot model remote context, which also limits its performance on CD. In contrast, Transformer does well in modeling remote contextual information. To make an end, in order to make full use of the advantages of both, we fully combine CNN and Transformer and propose multiscale and multisupervised hierarchical network for RS Image CD, called DMSHNet. First, we introduce multiple convolution kernels of different sizes in the Siamese encoder to help DMSHNet perceive information of different scales. Second, we develop the change information enhancement module (CIEM), which mainly generates differential features at different layers. CIEM uses simple absolute value subtraction and atrous convolution to highlight changing information and suppress unchanged information in different ranges. Third, we propose multisupervised and multiscale cascade module (DMSCM), which integrates multilayer differential features generated by CIEM on the basis of fully considering local information, global information, and multiscale information. We have conducted sufficient experiments on four public datasets, and the experimental results show that our DMSHNet achieves excellent performance. Our source code is available at https://github.com/ahlpc/DMSHNet.git.

The hot-working behavior of high-Mn austenitic steel for liquefied natural gas carriers at the deformation temperature in the range of 1073–1273 K and the strain rate in the range of 0.01–10 s−1was studied on a Gleeble-3800 thermomechanical simulator using a compression test. Electron backscatter diffraction was used to study the microstructure after deformation. Under each deformation condition, a peak stress appears in the stress-strain curve, which conforms to traditional dynamic recrystallization hot-working flow stress curves. A hyperbolic sine-law-type constitutive equation was established to predict the peak stress. The thermal deformation activation energy was 414.19 kJ/mol, and the stress index nwas 4.94. The texture of the deformed grains consisted of strong <110> and weak <100> fibers along the compression direction. The main recrystallization mechanism was discontinuous dynamic recrystallization. The grain size of the discontinuous dynamic recrystallization grains tended to increase with increasing deformation temperature or decreasing strain rate. Processing maps were drawn based on the dynamic material model. At high deformation temperatures, the power consumption factor of dynamic recovery was greater than that of dynamic recrystallization, whereas at low deformation temperatures, the power consumption factor of discontinuous dynamic recrystallization was greater than that of dynamic recovery. There are two flow instability regions in the processing maps, 1243–1273 K/1-10 s−1and 1073–1203 K/0.05–10 s−1. The formation of a ‘necklace microstructure’ was the main cause of deformation instability. The optimized process parameters for industrial production were 1243–1273 K/1-10 s−1.

Electronic ink (E‐ink) displays have become increasingly popular in e‐books due to their paper‐like appearance, readability in direct sunlight, low power consumption, and flexible sizing. However, the slow switching speed of bistable LCDs and E‐ink limits their ability to play animations. This paper proposes a novel method for fabricating fast‐ switching bistable liquid crystal displays capable of playing animations. The research is based on a new type of bistable LCD technology that achieves lower driving voltages than existing E‐ink displays. The research team has significant experience developing bistable displays and has invented many new technologies in their laboratory. The proposed technology combines the benefits of bistable displays with the ability to play animations, a significant advancement in display technology.

Gadolinium chelates for tumor magnetic resonance imaging (MRI) face challenges such as inadequate sensitivity, lack of selectivity, and risk of Gd leakage. This study presents a single-atom Gd nano-contrast agent (Gd-SA) that enhances tumor MRI. Isolated Gd atoms coordinated by six N atoms and two O atoms are atomically dispersed on a hollow carbon nanosphere, allowing the maximum utilization of Gd atoms with reduced risk of toxic Gd ion leakage. Owning to the large surface area and fast exchange of relaxed water molecules, Gd-SA shows excellent T1-weighted magnetic resonance enhancement with a r1value of 11.05 mM–1s–1at 7 T, which is 3.6 times that of the commercial gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA). In vivoMRI results show that the Gd-SA has a higher spatial resolution and a wider imaging time window for tumors than Gd-DTPA, with low hematological, hepatic, and nephric toxicities. These advantages demonstrate the great potential of single-atom Gd-based nanomaterials as safe, efficient, and long-term MRI contrast agents for cancer diagnosis.

The high temperature melting and sintering of Cu powder will seriously limit the coverage of graphene on the surface of Cu powder during the in-situgeneration of graphene. To solve this problem, MgO was added as a dispersant preventing Cu powders from bonding together due to surface melting during the chemical vapor deposition. The results show that the graphene/Cu powder prepared by this method had higher coverage, and the graphene/Cu composite sintered had better mechanical and anti-corrosion properties. It was attributed to the grain refinement strengthening effect and dislocation strengthening effect by the introduction of graphene. Meanwhile, graphene reduced the coverage of CuCl during Cl−corrosion. Therefore, this method provided a new idea for the preparation of high strength and high corrosion-resistant graphene/Cu composites.

The most common electronic paper technology is E‐ink, which enables many novel applications such as e‐readers, watches and electronic shelf labels. However, due to the TFT backplane driving and complex production processes, the cost of this technology is high, which limits its popularity. Recently, a low‐cost π‐bistable twist nematic (π‐BTN) liquid crystal display with a high pretilt angle is proposed. It has the same structure and production method as an ordinary liquid crystal display. Passive driving enables the manufacture of high‐resolution bistable displays without the use of thin‐film transistors. Compared with the current bistable twist nematic display technology, the high pretilt angles structure helps to achieve a lowvoltage and fast‐respond bistable display. This wide viewing angle, high contrast and TFT‐free display is a promising candidate for flexible displays.

Due to their unique surface characteristics, oil-water separation membranes with superhydrophilic and underwater superoleophobic properties have promising applications in oil-water separation processes. However, the microstructure and chemical composition of the material surfaces are prone to degradation in harsh environments. This article employs nanosecond laser etching to improve the deposition quality of fumed SiO2for the fabrication of superhydrophilic and underwater superoleophobic separation membranes. Various analytical methods are used to characterize the separation membranes. Nanosecond laser etching creates rough, ripple-like microstructures on stainless steel mesh, which not only enhances the deposition of fumed SiO2but also minimizes the interaction between solids and oil. This results in improved wetting characteristics and underwater oil repellency, significantly boosting both the performance and durability of the membrane. The prepared separation membrane demonstrated an average separation efficiency of 99.4% across five different oil-water mixtures, with all separation fluxes exceeding 58000L·m⁻²·h⁻¹. After soaking in an acid-base solution for 15 days and undergoing 25 friction tests, the underwater oil contact angle was maintained at 156.3°, demonstrating high separation efficiency and outstanding stability, with significant potential for application, particularly in harsh environments.

A poly(DOL)-based quasi-solid electrolyte for sodium metal batteries is prepared by in-situ polymerization, and the crucial roles of FEC on forming stable SEI and preventing interfacial side reactions are demonstrated.

Pulsewidth modulated (PWM) current-source converters (CSCs) have been attractive for high-power adjustable-speed machine systems with low carrier ratios. However, the high-order nonlinear model of CSC-fed machine systems, the distinct digital delay from the low carrier ratios, and the cross-coupling caused by coordinate transformation bring great challenges to design of high-performance stator current controller for such kind of machine systems. Firstly, this article derives the discrete-time complex-vector model for the CSC-fed permanent-magnet ac (PMAC) machine system with low carrier ratios considering the distinct digital delay and cross-coupling effect mentioned above. On that basis, the stator current controller is proposed with the modified controller parameters and the compensation technique to improve both dynamic performance and stability of the CSC-fed PMAC machine systems with low carrier ratios. The theoretical analysis and controller design process have been presented in detail to provide a guide for the model derivation and controller design. The experiments on a laboratory prototype are conducted to verify the effectiveness of the developed modeling and controller.

In this paper, based on the double strip silicon nitride platform, we designed and fabricated a low loss continuously tunable broadband optical delay line, which contains a 5-bit optical switched delay line and a single tunable optical ring resonator working at “off-resonance”. Optical double sideband modulation link measurement results show it can achieve continuous delay tuning of 395.5 ps and in-band delay fluctuations of about 4 ps and 1 ps were obtained in 8 GHz and 5 GHz working bandwidths, respectively. In addition, the proposed optical delay line has a low on-chip insertion loss of 3 dB and a very low optical loss delay ratio of 0.0022 dB/ps. Moreover, it's delay tuning range can be easily increased by cascading more thermo-optic switches. The delay bandwidth can be expanded by adopting the optical single sideband modulation or increasing the FSR of the optical ring resonator. This integrated tunable optical delay line with good overall performances and expand ability shows great potential for microwave photonic applications.

In this paper, the small-signal stability of a DC current flow controller (CFC) integrated meshed multi-terminal HVDC (MTDC) system is investigated with unique contributions: (1) The dynamics of a multi-line CFC, interconnected voltage- source converters (VSCs) and the DC transmission lines are considered in the small-signal modelling. (2) The switching effect of the capacitive components in the π-type DC transmission lines is identified. The comparative studies of modelling the DC transmission lines using π-type/T-type equivalent circuit are conducted. (3) The impact of the CFC on the AC side of the MTDC system is taken into account with analysis of the critical short-circuit ratio (CSCR) through root-locus analysis and participation factors. The relationship of the SCR with VSC outer-loop control and power transfer is analyzed. (4) The influence of the CFC control system/structural parameters on the small-signal stability of the entire system is investigated. The relationship of the CFC integration with the VSC outer-loop control is analyzed. The adjustment of single/multiple parameters for enhancing the system stability and a sequential parameter tuning approach for multiple parameters are explained. The effectiveness of the proposed method applied in different MTDC systems with CFC is verified. It would be useful for the configuration and parametric design of the CFC integrated meshed MTDC systems.

Silicon optical switching delay line (OSDL) chip, which composed of optical switches cascaded with optical waveguides of different lengths, has the merits of broadband true time delay and high delay accuracy, and is one of the key components in microwave photonic beamforming system. Due to the inevitable manufacturing errors of silicon photonic chips, the driving voltages of the “through” and “cross” states of each optical switch in OSDL need to be calibrated separately to ensure properly switching among different delay states. In general, additional optical power monitor taps or variable optical attenuators (VOAs) can be added into OSDL to achieve the switching voltage calibration processes of all the optical switches. However, adding additional optical power monitor taps after each optical switch will increase the extra loss of the delay line, also the I/O ports will be greatly increased. Introducing silicon VOAs based on carrier injection in each delay stage of the silicon OSDL will increase the manufacturing cost and control complexity. Therefore, a simple and non-invasive calibration technique for all the optical switches in OSDL chip is greatly needed. Here, based on the interferograms induced by the cascade unbalanced Mach-Zehnder interferences formed in OSDL, we propose a simple and effective calibration method for silicon OSDL chip without introducing additional components. As a proof of concept, we calibrated and measured all the delay states of a 5-Bit silicon OSDL chip, and the measured results agree well with those obtained with optical power monitor taps.

One of the primary objectives in chemistry research is to observe atomic motions during reactions in real time. Although X-ray free-electron lasers (XFELs) have facilitated the capture of reaction intermediates using time-resolved serial femtosecond crystallography (TR-SFX), only a few natural photoactive proteins have been investigated using this method, mostly due to the lack of suitable phototriggers. Here we report the genetic encoding of a xanthone amino acid (FXO), as an efficient phototrigger, into a rationally designed human liver fatty-acid binding protein mutant (termed XOM), which undergoes photo-induced C–H bond transformation with high selectivity and quantum efficiency. We solved the structures of XOM before and 10–300 ns after flash illumination, at 1.55–1.70 Å resolutions, and captured the elusive excited-state intermediates responsible for precise C–H bond activation. We expect that most redox enzymes can now be investigated by TR-SFX, using our method, to reveal reaction intermediates key for their efficiency and selectivity.

In this paper, the control methodology of the common capacitor voltage and the DC current flow controller (DC CFC) under self-fault conditions are investigated with the following two contributions. (1) A selection method of the common capacitor voltage based on various specific control requirements with explicit control margins of the DC line currents is proposed with analytic derivations of two-line/three-line DC CFCs in the meshed three-terminal/four-terminal high-voltage direct current grids (HVDC), respectively. (2) The impact of different self-faults of the DC CFC on the control performance of the DC line currents is analyzed with a simplified topology with unidirectional current flow presented. Case studies are conducted in the time-domain simulation environment PSCAD/EMTDC and the results justify the effectiveness of the theoretical analysis. The proposed common capacitor voltage control method and self-fault analysis would be useful for practical applications of the DC CFC under both steady and transient states.

The design of solid-state electrolyte (SSE) entails controlling not only its bulk structure but also the internal (e.g., grain boundary and pore) and heterophase (e.g., anode-SSE reaction layer) interfaces. Moreover, defects are integral for establishing both the initial all-solid-state battery (ASSB) cell performance and its ultimate cycling lifetime. This topical review discusses 5 highly promising inorganic lithium-, sodium-, and potassium-based SSEs, providing case studies of strategies to enhance ionic conductivity, tune the internal and heterophase interfaces, and prevent dendrites and deleterious side reactions. The primary focus is on garnet LLZO (Li7La3Zr2O12), argyrodite (Li6AS5X, A = P, Sb and X = Cl, Br, I), Na3AB4(A = P, Sb, As and B = S, Se), and NASICON-type electrolytes, with several exploratory potassium systems being presented as well. The article begins with a discussion of the superionic conduction mechanisms, which is assisted by defects, topology, correlation, and disorder. The discussion then shifts to the thermodynamic or kinetic phase stability of metastable SSEs, followed by the SSE internal interfaces (pores and grain boundaries), and finally the complex microstructure associated with the reactive boundaries between the SSE and the metal anode and the SSE and the high-voltage ceramic cathode. This review explores why SSE systems with highly promising bulk ionic conductivity values do not demonstrate comparable performance in full cells. A major cause is the cycling-induced formation of ionically insulating but electrically conducting new phases at both the anode and the cathode. For the SSEs that do not rapidly decompose when contacting the anode, site-specific variations in ionic conductivity/electrical resistivity lead to growth of metal dendrites. In each electrolyte class, creative fabrication strategies have been employed to minimize, but not fully eliminate, new phase formation and dendrites, creating ample opportunities for additional analytical and synthesis-focused research. The emphasis of the discussion is on the bulk doping strategies for SSEs, emerging simulation and characterization findings in relation to SSE performance and cell failure, and new synthesis approaches and cell architectures to improve cycling stability. Throughout the article, outstanding scientific questions are identified, and future research directions are proposed.

Objective Emerging evidence has indicated that excessive reactive oxygen species (ROS) have detrimental effects on osteoarthritis (OA). This study aimed to elucidate the effects of melatonin (MT), an antioxidant indolamine secreted from the pineal gland, on chondrocyte senescence and cartilage degeneration, thereby clarifying the underlying mechanisms of ROS-induced OA pathogenesis.Design Hydrogen peroxide (H2O2) was used to induce oxidative stress in rat chondrocytes. ROS levels were evaluated using cytometry and immunofluorescence. Cell viability was detected using the Cell Counting Kit-8 (CCK-8) assay. Western blotting and qPCR (Quantiative Real-Time Polymerase Chain Reaction) were used to examine apoptosis and autophagy. For in vivoexperiments, male Sprague-Dawley rats were randomly divided into a sham-operated group, DMM (destabilization of the medial meniscus) surgery group, and surgery groups that received melatonin. Knee joints were collected and stained for histological analysis.Results The data demonstrated that melatonin treatment significantly suppressed H2O2-induced matrix degradation and apoptosis, and maintained mitochondrial redox homeostasis. In addition, an enhancement of autophagic flux was observed through western blotting. These findings corresponded with activation of the AMPK/Foxo3 signaling pathways upon melatonin treatment. Histological staining and transmission electron microscopy (TEM) micrographs also demonstrated that melatonin alleviated cartilage ossification and chondrocyte hypertrophy in vivo.Conclusions Our results indicated that melatonin protected chondrocytes via mitochondrial redox homeostasis and autophagy. The effects of melatonin on senescence may apply to other age-related diseases. Thus, melatonin may have multiple potential therapeutic applications.

AbstractIn nature, competing species often achieve coexistence through niche differentiation. We examined this phenomenon for Pachycrepoideus vindemmiaeand Spalangia endius(Hymenoptera: Pteromalidae), two species of pupal parasitoids that are considered biological control agents of house fly, Musca domestica(Diptera: Muscidae). We examined the ability of each species, alone and in combination, to locate host pupae buried at different depths (0, 1, 2, 4, and 6 cm) in three types of substrate (sand, dry wheat bran, and spent fly diet). We then evaluated the competitiveness of each species by allowing first one species, then the other species, to parasitise host individuals within time periods ranging from less than 2 hours to 96 hours of each other. Spalangia endiusexhibited greater ability than did P. vindemmiaeto locate host pupae buried at depths below one centimetre. Conversely, P. vindemmiaeexhibited a greater competitive ability, being more likely to emerge from pupae co-parasitised by S. endius, regardless of oviposition interval or sequence. Our findings suggest that these two parasitoid species coexist through niche differentiation. Our findings also indicate that to increase the effectiveness of biological control, the environmental conditions and risk of interspecific competition should be considered when selecting parasitoid species for release.

Fluid-solid interaction (FSI) poses a significant challenge in engineering applications. Due to the presence of off-diagonal coupling terms in the matrices, it is difficult to use explicit time integration method directly. Consequently, the whole system often needs to be solved using implicit method, albeit at the expense of considerably increased computational cost. In this paper, an innovative approach, namely an explicit-implicit hybrid scaled boundary finite element method (SBFEM), is proposed to mitigate this issue. In this method, the implicit time integration scheme is employed to tackle the coupling part between solid and fluid, while the remainder of the system is solved directly by explicit time integration. The solid and fluid domains are both discretized by an automatic quadtree mesh generation, ensuring efficient mesh size transitions and facilitating local mesh refinement near the interface. An overlapping zone is constructed near the interface for data exchange between the explicit and implicit schemes, which is derived directly from the quadtree data structure. The elements in the quadtree mesh are treated as general polygons formulated by the SBFEM. As a result, the proposed method capitalizes on the advantages of both implicit and explicit techniques, leading to enhanced computational efficiency. Combining the quadtree mesh with the explicit-implicit hybrid SBFEM allows for the simulation of wave propagation in FSI system with complex geometric shapes and boundary conditions. Benchmark tests are conducted to verify the accuracy of the proposed method, followed by a vibration analysis of an underwater cavity to demonstrate its engineering applicability. [ABSTRACT FROM AUTHOR]

In order to realize the real-time electromagnetic transient simulation of grid-connected photovoltaic power generation system with small time step, a heterogeneous multiplexed parallel real-time simulation method based on field programmable gate array (FPGA) and central processor is studied. According to the simulation accuracy requirements of the high and low frequency decoupling module, a differentiated simulation step size is used to solve the problem, and a 1us/50us FPGA-CPU multi-rate real-time simulation platform is constructed, in which the FPGA simulation part meets the real-time requirements of small-step transient simulation through the optimization of the response matching method and the EMTP algorithm, the offline simulation results are compared with Simulink, and the model before and after optimization is analyzed, the real-time electromagnetic transient simulation results are compared with Simulink, and the model before and after optimization is analyzed. By comparing the offline simulation results with Simulink and analyzing the FPGA resource consumption before and after model optimization, the accuracy and real-time performance of the co-simulation method for real-time simulation of grid-connected photovoltaic systems are verified.

Air-flow sensing is essential in broad applications of weather forecasting, ocean monitoring, gas leakage alarming, and health monitoring. However, in severe environments where electrical power supply and cable connection are not available, the sensing of air flow in a self-powered way is a challenging issue. In this work, we reported a tribo-induced smart reflector to achieve the self-powered wireless sensing of the air flow by combining an aerodynamics-driven triboelectric nanogenerator (TENG) and a silver-coated polymer network liquid crystal. Upon being driven by the air flow, the developed reflector performed specular and diffused reflectance without and with charging by the TENG, respectively, enabling wireless sensing through mechanical–electrical–optical signal conversion. In the developed sensing paradigm, the sensing module can be fully self-powered without the need of signal pre-amplification, which is electrically separated from the light source and detection modules without cable connections. The applications of self-powered wireless wind speed sensing and breath monitoring were performed to demonstrate the effectiveness of the developed paradigm toward self-powered wireless sensing nodes in the internet of things.

The optoelectronic oscillator (OEO) generates low-phase noise and high-frequency microwave signals thanks to a high Q-factor cavity with long and low-loss fiber delay. Traditionally, for the desired mode selection from the ultradense cavity modes, a narrowband electrical filter is needed, whose frequency tuning is very limited. On the other hand, for a tunable OEO offered by a microwave photonic filter (MPF), a paradox existed between the large number of cavity modes and the wide MPF bandwidth. Here, we achieve a tunable OEO using the mode-selection mechanism of parity-time symmetry, which overcomes the paradox. A high Q-factor silicon nitride microdisk resonator (Si_3N_4 MDR) is introduced to achieve frequency filtering and tuning. Moreover, the experimental results reveal that the tunable OEO generates a signal range from 3 GHz to 20 GHz with a phase noise about −120dBc/Hz at a 10 kHz offset frequency.

The DC current flow controller (CFC) has capability of enhancing the control freedom of current/power flow in multi-terminal DC (MTDC) grids and solving the barrier of uncontrollability of DC branch currents. The control margins of the DC branch currents can be further improved if the power flow reversal is achieved with the DC CFC. An improved DC CFC (I-DCCFC) utilized in the meshed MTDC (M2TDC) grid is investigated with three contributions: (1) Regarding a traditional DC CFC (T-DCCFC), its operational mode and operating principle are analysed. The fact that T-DCCFC only has singular quadrant operation capability, which constrains the power flow reversal, is explained. (2) The I-DCCFC with double quadrants operation capability is presented. Its operating principle with power flow reversal capability is analysed. (3) Based on the control strategy of the T-DCCFC, the control strategy of the I-DCCFC is developed and the ability to isolate the DC fault is analysed. The simulation model of a three-terminal M2TDC grid with the I-DCCFC is established in PSCAD/EMTDC. The effectiveness of the I-DCCFC in controlling the DC branch currents with power flow reversal capability and fault isolation under the fault condition is verified by the simulation results. As the I-DCCFC inherits the modular design concept with strong scalability, it can be expanded into an improved multi-line DC CFC according to the actual demands.

The most common electronic paper technology is E‐ink, which enables many novel applications such as e‐readers, watches and electronic shelf labels. However, due to the TFT backplane driving and complex production processes, the cost of this technology is high, which limits its popularity. Recently, a low‐cost π‐bistable twist nematic (π‐BTN) liquid crystal display with a high pretilt angle is proposed. It has the same structure and production method as an ordinary liquid crystal display. Passive driving enables the manufacture of high‐resolution bistable displays without the use of thin‐film transistors. Compared with the current bistable twist nematic display technology, the high pretilt angles structure helps to achieve a low‐voltage and fast‐respond bistable display. This wide viewing angle, high contrast and TFT‐free display is a promising candidate for flexible displays.

Potassium metal serves as the anode in emerging potassium metal batteries (KMBs). It also serves as the counter electrode for potassium ion battery (KIB) half-cells, with its reliable performance being critical for assessing the working electrode material. This first-of-its-kind critical Account focuses on the dual challenge of controlling the potassium metal-substrate and the potassium metal–electrolyte interface so as to prevent dendrites. The discussion begins with a comparison of the physical and chemical properties of K metal anodes versus the much oft studied Li and Na metal anodes. Based on established descriptions for root causes of dendrites, the problem should be less severe for K than for Li or Na, while in fact the opposite is observed. The key reason that the K metal surface rapidly becomes dendritic in common electrolytes is its unstable solid electrolyte interphase (SEI). An unstable SEI layer is defined as being non-self-passivating. No SEI is perfectly stable during cycling, and all SEI structures are heterogeneous both vertically and horizontally relative to the electrolyte interface. The difference between a “stable” and an “unstable” SEI may be viewed as the relative degree to which during cycling it thickens and becomes further heterogeneous. The unstable SEI on K metal leads to a number of interrelated problems, such as low cycling Coulombic efficiency (CE), a severe impedance rise, large overpotentials, and possibly electrical shorting, all of which have been reported to occur as early as in the first 10 plating/stripping cycles. Many of the traditional “interface fixes” employed for Li and Na metal anodes, such as various artificial SEIs, surface membranes, barrier layers, secondary separators, etc., have not been attempted or optimized for the case of K. This is an important area for further exploration, with an understanding that success may come harder with K than with Li due to K-based SEI reactivity with both ether and ester solvents.

We combined advanced TEM (HRTEM, HAADF, EELS) with solid-state (SS)MAS NMR and electroanalytical techniques (GITT, etc.) to understand the site-specific sodiation of selenium (Se) encapsulated in a nanoporous carbon host. The architecture employed is representative of a wide number of electrochemically stable and rate-capable Se-based sodium metal battery (SMB) cathodes. SSNMR demonstrates that during the first sodiation, the Se chains are progressively cut to form an amorphous mixture of polyselenides of varying lengths, with no evidence for discrete phase transitions during sodiation. It also shows that Se nearest the carbon pore surface is sodiated first, leading to the formation of a core–shell compositional profile. HRTEM indicates that the vast majority of the pore-confined Se is amorphous, with the only localized presence of nanocrystalline equilibrium Na2Se2(hcp) and Na2Se (fcc). A nanoscale fracture of terminally sodiated Na–Se is observed by HAADF, with SSNMR, indicating a physical separation of some Se from the carbon host after the first cycle. GITT reveals a 3-fold increase in Na+diffusivity at cycle 2, which may be explained by the creation of extra interfaces. These combined findings highlight the complex phenomenology of electrochemical phase transformations in nanoconfined materials, which may profoundly differ from their “free” counterparts.

Herein, a strategy is presented for improving the electrochemical performance of a LiNixCoyMn1–x–yO2layered oxide involving the coating of rock salt-type LiTiO2on the surface via a hydrothermal method followed by a calcination process. A thickness of approximately 10 nm of LiTiO2coated on the surface of LiNi0.5Co0.2Mn0.3O2(NCM523) has been achieved, and the optimal molar ratio (LiTiO2/NCM523) is found to be 1.0 mol %. The LiTiO2@LiNi0.5Co0.2Mn0.3O2when used as a cathode material exhibits not only a higher capacity retention but also a more enhanced rate performance in comparison with that of pristine NCM523. The LiTiO2layer protects the NCM523 active particles from being eroded by the electrolyte and reduces the volume change of the electrode active particles before and after lithium-ion intercalation/deintercalation during cycling. These new findings contribute toward the design of a stable structured nickel-based cathode material for lithium-ion batteries.

Unraveling the essence of electronic structure effected by d-d orbital coupling of transition metal and methanol oxidation reaction (MOR) performance can fundamentally guide high efficient catalyst design. Herein, density functional theory (DFT) calculations were performed at first to study the d–d orbital interaction of metallic PtPdCu, revealing that the incorporation of Pd and Cu atoms into Pt system can enhance d-d electron interaction viacapturing antibonding orbital electrons of Pt to fill the surrounding Pd and Cu atoms. Under the theoretical guidance, PtPdCu medium entropy alloy aerogels (PtPdCu MEAAs) catalysts have been designed and systematically screened for MOR under acid, alkaline and neutral electrolyte. Furthermore, DFT calculation and in-situfourier transform infrared spectroscopy analysis indicate that PtPdCu MEAAs follow the direct pathway viaformate as the reactive intermediate to be directly oxidized to CO2. For practical direct methanol fuel cells (DMFCs), the PtPdCu MEAAs-integrated ultra-thin catalyst layer (4∼5 μm thickness) as anode exhibits higher peak power density of 35 mW/cm2than commercial Pt/C of 20 mW/cm2(∼40 μm thickness) under the similar noble metal loading and an impressive stability retention at a 50-mA/cm2constant current for 10 h. This work clearly proves that optimizing the intermediate adsorption capacity viad-d orbital coupling is an effective strategy to design highly efficient catalysts for DMFCs.

Layered transition metal dichalcogenides (TMDs) have exhibited huge potential as anode materials for sodium-ion batteries. Most of them usually store sodium via an intercalation–conversion mechanism, but niobium sulfide (NbS2) may be an exception. Herein, through in situ transmission electron microscopy, we carefully investigated the insertion behaviors of Na ions in NbS2and directly visualized anisotropic sodiation kinetics. Lattice-resolution imaging coupled with density functional theory calculations reveals the preferential diffusion of Na ions within layers of NbS2, accompanied by observable interlayer lattice expansion. Impressively, the Na-inserted layers can still withstand in situ mechanical testing. Further in situ observation vertical to the a/bplane of NbS2tracked the illusive conversion reaction, which could result from interlayer gliding or wrinkling associated with stress accumulation. In situ electron diffraction measurements ruled out the possibility of such a conversion mechanism and identified a phase transition from pristine 3R–NbS2to 2H–NaNbS2. Therefore, the NbS2anode stores Na ions via only the intercalation mechanism, which conceptually differs from the well-known intercalation–conversion mechanism of typical TMDs. These findings not only decipher the whole sodiation process of the NbS2anode but also provide valuable reference for unraveling the precise sodium storage mechanism in other TMDs.

Carbon dioxide (CO2) adsorption is a critical step to curbing carbon emissions from fossil fuel combustion. Among various options, transition metal oxides have received extensive attention as promising CO2adsorbents due to their affordability and sustainability for large-scale use. Here, the nature of binding interactions between CO2molecules and cationic scandium oxides of different sizes, i.e., ScO+, Sc2O2+, and Sc3O4+, is investigated by mass-selective infrared photodissociation spectroscopy combined with quantum chemical calculations. The well-accepted electrostatic considerations failed to provide explanations for the trend in the binding strengths and variations in the binding orientations between CO2and metal sites of cationic scandium oxides. The importance of orbital interactions in the driving forces for CO2adsorption on cationic scandium oxides was revealed by energy decomposition analyses. A molecular surface property, known as the local electron attachment energy, is introduced to elucidate the binding affinity and orientation-specific reactivity of cationic scandium oxides upon the CO2attachment. This study not only reveals the governing factor in the binding behaviors of CO2adsorption on cationic scandium oxides but also serves as an archetype for predicting and rationalizing favorable binding sites and orientations in extended surface–adsorbate systems.

The catalytic transformation of CO2into valuable products has garnered wide interest owing to both economic and environmental benefits, in which the chemical fixation of CO2into carbonate structures represents a crucial step that occurs on the adsorbed catalyst surfaces. Transition metal oxides with acidic and basic active sites have exhibited potential in promoting the carbonation of weakly bound CO2molecules. Here, the interactions between CO2molecules and the Sc3O4+cation in the gas phase are investigated by using infrared photodissociation spectroscopy in conjunction with quantum chemical calculations. Both end-on and various carbonate-containing configurations, including center and bridge carbonate structures, have been theoretically identified for the CO2-coordinated ion–molecule complexes. Based on the comparison between the experimental spectra and simulated spectra of low-lying isomers in the CO2antisymmetric stretching vibrational frequency region, isomers characterized by a bridge carbonate core structure are demonstrated to be the major contributors to the observed spectra. Examination of potential energy surfaces reveals lower energy barriers and simpler reaction routes for the conversion of molecularly bound CO2into a bridge carbonate moiety, providing reasonable explanations for their prevalence in the experiments.

This work affords new insights into energy storage mechanisms of Sb anode and valuable guidance for targeted optimization of alloy-typed anodes (not limited to Sb) toward advanced potassium-ion batteries.

Exploring novel hole transporting materials (HTMs) with high hole mobility and eco-friendly processability are imperative for the commercialization of perovskite solar cells (PSCs). However, there is a “trade-off” that the introduction of large-conjugated units aiming to ensure high hole mobility, inevitably compromises the green-solvent solubility of HTMs. In this work, a hybrid strategy of rigidity and flexibility is proposed, in which the conjugated unit is assembled by the rigid binaphthylamine core, and the amide-bond constitutes the flexible backbone. Polar solubilizing units ethylenedioxythiophene and thiophene are used as bridges to construct two kinds of polymers, cited as EDOT-SMe and T-SMe, respectively. Both polymers achieve high hole mobility, well-matched energy levels and efficient defect passivation effect toward the perovskite films. When processing the HTM films with the green solvent (2-methylanisole), the corresponding PSCs deliver fill factors as high as 82.7% for EDOT-SMe and 81.9% for T-SMe, respectively. Consequently, PCEs of 20.25% for EDOT-SMe and 20.09% for T-SMe are realized, outperforming that of commercial polymer poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA, 19.71%). Moreover, PSCs with these polyamides achieve good long-term stability. This work paves a new path for exploring efficient and green-solvent processable polymeric HTMs.

Energy storage devices are poised to take center stage in future distributed energy systems. Currently, the primary obstacles hindering the widespread adoption of hydrated salts in phase change accumulators are issues related to phase separation and thermal conductivity during extended cycling periods. In this study, we address these challenges by introducing deionized water into the mix and carefully controlling the material's layer height. We conducted a thorough investigation of the optimal interaction ratios and analyzed the resulting improvements in thermal storage capacity and cycling stability. To mitigate the phase separation problem, we incorporated deionized water while precisely regulating the material's layer height. This approach effectively allows the aqueous layer of the hydrated salt phase change material to make contact with or even cover the anhydrous salt layer, resolving the phase separation issue. The addition of a small amount of water destroys the original hydrogen bonding network of sodium acetate trihydrate to reduce its heat storage capacity, but the latent heat value is still at a high level. Moreover, the phase change material exhibits remarkable stability and heat storage capacity when maintained at a 2 cm layer height with 3 % deionized water. After 500 cycles, the latent heat value only experienced a minimal decrease of 0.78 %, demonstrating excellent cycle stability. In practical applications, it is essential to avoid phase separation in phase change materials by appropriately adjusting the material layer height or increasing the water content as needed when implementing them in heat accumulators. Additionally, our study proposes the use of a layered fin structure for heat accumulators, which was validated through Fluent simulations. These layered fins are exceptionally well-suited for directing heat transfer within the accumulator, offering superior heat transfer performance compared to other non-continuous fin structures.

Flower-like Co3O4hierarchical microspheres composed of self-assembled porous nanoplates were prepared by employing Pluronic F127 block-copolymer as template. The samples were characterized by powder X-ray diffraction(PXRD), scanning/transmission electron microscopy(SEM/TEM), and nitrogen adsorption-desorption at 77 K. The results show that the catalytic activity of Co3O4nanoflowers for the combustion of ventilation air methane is higher than that of commercial Co3O4. The superior catalytic performance of this material can be related to its dominantly exposed {112} crystal planes and higher content of surface Co3+.

The ever-growing demands of Li-ion batteries (LIBs) for high-energy and long-life applications, such as electrical vehicles, have prompted great research interest. Herein, by applying an interesting one-step high-temperature mixing method under hydrothermal conditions, ultrathin V3O7·H2O@C nanoribbons with good crystallinity and robust configuration are in situ synthesized as promising cathode materials of high-energy, high-power, and long-life LIBs. Their capacity is up to 319 mA h/g at a current density of 100 mA/g. Moreover, the capacity of 262 mA h/g can be delivered at 500 mA/g, and 94% of capacity can be retained after 100 cycles. Even at a large current density of 3000 mA/g, they can still deliver a high capacity of 165 mA h/g, and 119% of the initial capacity can be kept after 600 cycles. Importantly, their energy density is up to 800 Wh/kg, which is 48–60% higher than those of conventional cathode materials (such as LiCoO2, LiMn2O4, and LiFePO4), and they can maintain an energy density of 355 Wh/kg at a high power density of 8000 W/kg. Furthermore, based on ex situ X-ray diffraction and X-ray photoelectron spectroscopy technology, their exact charge–discharge behavior is reasonably described for the first time. Excitingly, it is found for the first time that the as-synthesized V3O7·H2O@C nanoribbons are also great promising cathode materials for Na-ion batteries.

Fire flooding (FF) has been one of the important thermal enhanced-oil-recovery technologies in developing heavy oil reservoir. Many scholars have carried out laboratory studies on the complex oil-displacement mechanism due to the complex physical and chemical reactions for fire flooding. However, almost no one had given an equation expression of gas injection and production during fire-flooding process. Therefore, the FF and flue gas flooding (FGF) experiments of one-dimensional combustion tubes were conducted. The oil-recovery differences of FF and FGF experiments under the same conditions were calculated, and a high linear correlation was found. The results showed that the FF effects were mainly affected by the flue-gas when the gas injection was low, and the combustion-front expansion (CFE) effects made the main contribution when the gas injection was high. The gas injection, water and liquid production were logarithmically treated and compared with the oil production. It was found a strong linear relationship between the two sets of experiments, and the linear relationship was stronger in the FGF experiment. Among all the linear relationships, the logarithm of water production and oil production had the strongest linear relationship. Based on this understanding, the water and oil production were connected from flue gas in FF process, and a novel FF equation was derived and obtained. Finally, the production curves on site of the two typical FF cases and the fitting curves of the FF equation were descripted and compared. The results showed that the novel equation can reflect and forecast the field performance by FF process in developing heavy oil reservoir.