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Lithium-ion batteries (LIBs) are widely used in electric vehicles and energy storage systems, making accurate state transition monitoring a key research topic. This paper presents a characterization method for large-format LIBs based on phased-array ultrasonic technology (PAUT). A finite element model of a large-format aluminum shell lithium-ion battery is developed on the basis of ultrasonic wave propagation in multilayer porous media. Simulations and comparative analyses of phased array ultrasonic imaging are conducted for various operating conditions and abnormal gas generation. A 40 Ah ternary lithium battery (NCMB) is tested at a 0.5C charge-discharge rate, with the state of charge (SOC) and ultrasonic data extracted. The relationship between ultrasonic signals and phased array images is established through simulation and experimental comparisons. To estimate the SOC, a fully connected neural network (FCNN) model is designed and trained, achieving an error of less than 4%. Additionally, phased array imaging, which is conducted every 5 s during overcharging and overdischarging, reveals that gas bubbles form at 0.9 V and increase significantly at 0.2 V. This research provides a new method for battery state characterization. [ABSTRACT FROM AUTHOR]

The commercialization of sodium batteries faces many challenges, one of which is the lack of suitable high-quality separators. Herein, we presented a novel natural silkworm cocoon-derived separator (SCS) obtained from the cocoon inner membrane after a simple degumming process. A Na||Na symmetric cell assembled with this separator can be stably cycled for over 400 h under test conditions of 0.5 mA cm−2–0.5 mAh cm−2. Moreover, the Na||SCS||Na3V2(PO4)3 full cell exhibits an initial capacity of 79.3 mAh g−1 at 10 C and a capacity retention of 93.6% after 1000 cycles, which far exceeded the 57.5 mAh g−1 and 42.1% of the full cell using a commercial glass fiber separator (GFS). The structural origin of this excellent electrochemical performance lies in the fact that cationic functional groups (such as amino groups) on silkworm proteins can de-solvate Na-ions by anchoring the ClO4− solvent sheath, thereby enhancing the transference number, transport kinetics and deposition/dissolution properties of Na-ions. In addition, the SCS has significantly better mechanical properties and thinness indexes than the commercial GFS, and, coupled with the advantages of being natural, cheap, non-polluting and degradable, it is expected to be used as a commercialized sodium battery separator material. [ABSTRACT FROM AUTHOR]

The rapid development of the Internet of Vehicles using centralized systems faces significant challenges, including reliability and security vulnerabilities and high latency. This paper introduces a blockchain-enabled authentication and communication network for scalable IoV to enhance security, reduce latency, and relieve the dependency on centralized infrastructures. The network applies blockchain-enabled domain name services and mutual authentication for fault tolerance consensus, such as PBFT and RAFT, featuring a primary layer of road side units and edge servers for inter-vehicle communication and a sub-layer within each vehicle for intra-vehicle communication. The study evaluates various scenarios and assesses roadside unit availability based on random distribution along vehicle routes. This paper also discusses the legal issues involved in the proposed model, highlighting that the IoV system should be governed by a contract-based decentralized IoV system comprising both smart contracts and traditional contracts. This model offers a novel approach to developing a decentralized, secure, efficient, and ethical IoV ecosystem, advancing autonomous and reliable vehicular networks. [ABSTRACT FROM AUTHOR]

Pedestrian Dead Reckoning (PDR) is a promising algorithm for indoor positioning. However, the accuracy of PDR degrades due to the accumulated error, especially in multi-floor buildings. This paper introduces a three-dimensional (3D) positioning method based on terrain feature matching to reduce the influence of accumulated errors in multi-floor scenes. The proposed calibration method involves two steps: motion pattern recognition and position matching-based calibration. The motion pattern recognition aims to detect different motion patterns, i.e., taking the stairs or horizontal walking, from the streaming data. Then, stair entrances and corridor corners are matched with transition points of motion patterns and pedestrian turning points, respectively. After matching, calibration is performed to eliminate the accumulated errors. By carrying out experiments on a two-floor closed-loop path with a walking distance about 145 m, it is shown that this method can effectively reduce the accumulated error of PDR, achieving accurate 3D positioning. The average error is reduced from 6.60 m to 1.37 m. [ABSTRACT FROM AUTHOR]

Fingermarks play an important role in document identification. At the same time, fingermarks on paper documents are often accompanied by signatures and background text, which introduce noise to the original fingermark textures and increase the difficulty of detection. A signed fingermark detection method based on deep residual networks and a decision-level fusion strategy was proposed to defend against spoofing attacks from fake fingermarks. Firstly, the multi-scale structure was introduced in the residual module, which improved the network's depth and breadth without increasing the parameters. Then, the multi-probability label strategy was refined and employed to enhance the local encoding ability of the feature extraction. A score fusion strategy was designed, with weights allocated based on the difference in signed interference levels of local image blocks. Finally, a model fusion strategy based on evidence theory was suggested, which improved detection accuracy by leveraging complementarity between models. A large-scale fingermark database was established, which included real fingermarks made from real fingers and fake fingermarks made from various materials, and this was divided into two sub databases: signed and unsigned. The experimental results show that the proposed method achieves 96.16% accuracy based on the fingerprint dataset of the global liveness detection competition called LivDet2017 and achieves 99.30% accuracy based on the signed fingermark database, while it has good resistance to spoofing attacks from unknown materials. [ABSTRACT FROM AUTHOR]

Live prey is characterized by balanced rich nutrients and high palatability and is widely used for the seedling cultivation of freshwater dark sleeper (Odontobutis potamophila) larvae. In this study, we evaluated the effects of four groups of paired feeding regimens (group C (Daphnia magna), group L (Limnodrilus hoffmeisteri), group H (Hypophthalmichthys molitrix fry), and group M (mixed groups C, L, and H)) on glycolipid and energy metabolism in O. potamophila larvae. We observed that fatty acid synthase (FAS) and sterol-regulatory-element-binding protein-1 (SREBP-1) mRNA levels were significantly lower in group H when compared to mRNA levels in the other three groups (p < 0.05) and that carnitine palmitoyltransferase 1α (CPT1-α) mRNA levels were significantly lower in group L when compared to group M (p < 0.05). Relative glucokinase (GK) expression levels were significantly lower in group M when compared to the other three groups (p < 0.05). Using proteomics, we analyzed and compared groups H and L and identified 457 differentially expressed proteins (DEPs), of which 151 were significantly up-regulated and 306 were significantly down-regulated. In the comparison of group M with groups C, L, and H, we found significant enrichment in glycolytic processes, the endoplasmic reticulum lumen, NAD binding, intermediate filaments, and nutrient reservoir activity. Our results provide a theoretical guidance for bait selection during larvae cultivation stages in carnivorous fish. [ABSTRACT FROM AUTHOR]

This study investigates the dividend optimization problem in the entropy regularization framework in the continuous-time reinforcement learning setting. The exploratory HJB is established, and the optimal exploratory dividend policy is a truncated exponential distribution. We show that, for suitable choices of the maximal dividend-paying rate and the temperature parameter, the value function of the exploratory dividend optimization problem can be significantly different from the value function in the classical dividend optimization problem. In particular, the value function of the exploratory dividend optimization problem can be classified into three cases based on its monotonicity. Additionally, numerical examples are presented to show the effect of the temperature parameter on the solution. Our results suggest that insurance companies can adopt new exploratory dividend payout strategies in unknown market environments. [ABSTRACT FROM AUTHOR]

Electro-optic modulator (EOM) is one of the key devices of high-speed optical fiber communication systems and ultra-wideband microwave photonic systems. Silicon–organic hybrid (SOH) integration platform combines the advantages of silicon photonics and organic materials, providing a high electro-optic effect and compact structure for photonic integrated devices. In this paper, we present an SOH-integrated EOM with comprehensive investigation of EOM structure design, silicon waveguide fabrication with Slot structure, on-chip poling of organic electro-optic material, and characterization of EO modulation response. The SOH-integrated EOM is measured with 3 dB bandwidth of over 50 GHz and half-wave voltage length product of 0.26 V·cm. Furthermore, we demonstrate a microwave photonics phase shifter by using the fabricated SOH-integrated dual parallel Mach–Zehnder modulator. The phase shift range of 410° is completed from 8 GHz to 26 GHz with a power consumption of less than 38 mW. [ABSTRACT FROM AUTHOR]

Sonar images are inherently affected by speckle noise, which degrades image quality and hinders image exploitation. Despeckling is an important pre-processing task that aims to remove such noise so as to improve the accuracy of analysis tasks on sonar images. In this paper, we propose a novel transformer-based generative adversarial network named SID-TGAN for sonar image despeckling. In the SID-TGAN framework, transformer and convolutional blocks are used to extract global and local features, which are further integrated into the generator and discriminator networks for feature fusion and enhancement. By leveraging adversarial training, SID-TGAN learns more comprehensive representations of sonar images and shows outstanding performance in speckle denoising. Meanwhile, SID-TGAN introduces a new adversarial loss function that combines image content, local texture style, and global similarity to reduce image distortion and information loss during training. Finally, we compare SID-TGAN with state-of-the-art despeckling methods on one image dataset with synthetic optical noise and four real sonar image datasets. The results show that it achieves significantly better despeckling performance than existing methods on all five datasets. [ABSTRACT FROM AUTHOR]

With the continuous development of the world's aerospace industry, countries have put forward higher requirements for thermal protection materials for aerospace vehicles. As a nano porous material with ultra-low thermal conductivity, aerogel has attracted more and more attention in the thermal insulation application of aerospace vehicles. At present, the summary of aerogel used in aerospace thermal protection applications is not comprehensive. Therefore, this paper summarizes the research status of various types of aerogels for thermal protection (oxide aerogels, organic aerogels, etc.), summarizes the hot issues in the current research of various types of aerogels for thermal protection, and puts forward suggestions for the future development of various aerogels. For oxide aerogels, it is necessary to further increase their use temperature and inhibit the sintering of high-temperature resistant components. For organic aerogels, it is necessary to focus on improving the anti-ablation, thermal insulation, and mechanical properties in long-term aerobic high-temperature environments, and on this basis, find cheap raw materials to reduce costs. For carbon aerogels, it is necessary to further explore the balanced relationship between oxidation resistance, mechanics, and thermal insulation properties of materials. The purpose of this paper is to provide a reference for the further development of more efficient and reliable aerogel materials for aerospace applications in the future. [ABSTRACT FROM AUTHOR]

The existing tunnel will inevitably be disturbed when the new subway station is constructed cross under it at zero distance. Three innovative construction schemes were proposed, their effects on deformation control were compared by numerical simulations, and the mechanism of the influence of different tunnel support and excavation methods on the deformation control in them was further explored in order to seek a better scheme in this paper. The results show that the settlement of the existing tunnel in Scheme I (L-type beam + full-face excavation) is the greatest, and that the one in Scheme III (temporary steel column + double-pilot tunnel) is the smallest, but the settlement during excavation changes significantly, along with the large deformation on the side walls of the undercrossing area. Scheme III is not recommended because it is difficult to control and the construction effect is mediocre. Due to the existence of a large free face, the settlement of both sides of the existing tunnel is larger when the L-type beam supports the tunnel, and the bottom of the middle wall bears large compressive stress. The settlement of the existing tunnel excavated by the double-pilot tunneling method is less than that of the full-face tunneling method under the same tunneling support method, and the increase in settlement during the tunneling with the L-type beams is greater than that with the pier columns. In comprehensive consideration, Scheme II (pier column + double-pilot tunnel method) or combined pier column + double-pilot tunnel can control the deformation better. [ABSTRACT FROM AUTHOR]

A nano-SiO2 inorganic insulation layer was coated on the surface of FeSi magnetic powder via in situ fluidised vapour deposition. The surface was then coated with organosilicon resin to form an inorganic/organic double-insulating layer. Post-forming and annealing, a ferrosilicon magnetic powder core was prepared. The effects of organosilicon resin content and pressing pressure on the permeability and loss of the ferrosilicon magnetic core were studied. When the ferrosilicon magnetic core was doubly insulated with SiO2/silicone resin, the silicone resin content increased, the insulation coating gradually thickens, and the saturation magnetic-induction intensity of the magnet gradually decreases; the density and effective permeability showed a trend of increasing first and then decreasing. Increasing the forming pressure can reduce the loss of the core, thereby improving the performance of the core and increasing the permeability without damaging the double-cladding layer. In the powder with the optimised silicone resin content (1.5 wt.%), the magnetic properties of the magnetic core were maximised after preparation at 1500 MPa followed by heat treatment at 773 K. The saturation magnetisation was 187.5 emu/g and the resistivity and permeability reached 10.5 Ω·cm and 49.6, respectively, at 100 mT and 50 kHz. The total loss was 905 mW/cm3. [ABSTRACT FROM AUTHOR]

The global temperature gradually decreased from the Cretaceous Santonian to Campanian, while angiosperms evolved rapidly and gradually became dominant. The Songliao Basin, NE China, contains abundant fossil palynomorphs from the Santonian to Campanian age. A thorough investigation of fossil palynomorphs in borehole ZKY2-1 of the SW Songliao Basin was performed, reconstructing the vegetation and paleoclimate transition from the Santonian–earliest Campanian (lower Nenjiang Formation) to the late Campanian (Sifangtai Formation). Eighty form-genera from borehole ZKY2-1 have been identified. Three palynomorph assemblages were identified: the Schizaeoisporites–Cyathidites–Inaperturopollenites assemblage, Schizaeoisporites–Classopollis–Retitricolporites assemblage, and Schizaeoisporites–Aquilapollenites–Tricolporopollenits assemblage, from bottom to top. Based on palynological analysis from ZKY2-1 and other boreholes in the Songliao Basin, angiosperm pollen proportion in the Sifangtai Formation is significantly higher than in the lower Nenjiang Formation, indicating rapid angiosperm spread from late Santonian to Campanian. Palynological records indicate relatively humid climate during this period; the content of cool palynological types increased from the lower Nenjiang Formation to the Sifangtai Formation, suggesting a transition from warm to cool climate during the late Santonian–earliest Campanian to the late Campanian. The new palynological evidence from the Songliao Basin reveals a global cooling on land and sea during the late Santonian–Campanian period. This climate change may further promote angiosperm spread during the Late Cretaceous period. [ABSTRACT FROM AUTHOR]

To reveal how CaF2 improves the dissolution ratios of aluminum and iron ions in coal gangue, CaF2 and hydrochloric acid are used to extract Al3+ and Fe3+ from the coal gangue calcined powder. The leaching ratios of Al3+ and Fe3+ are measured, and the filter residues are analyzed by BET, XRD, and SEM. The results show that adding 3% CaF2 could increase the extraction ratio of Al3+ from 62.96% to 92.10% under optimized conditions, and that of Fe3+ is increased from 85.12% to 95.73%. The mechanism of CaF2 as an auxiliary to improve the leaching ratio of Fe3+ is that HF reacts with the thin layers of gangue calcined powder containing silica to form soluble SiF4, thus forming pores that promote the diffusion of H+ and inner ions, improving the leaching ratios of Al3+ and Fe3+. Finally, the CaF2-assisted acid leaching process is optimized. The results showed that it is efficient and feasible to extract Al3+ and Fe3+ with the assistance of CaF2 and that HF has a catalytic effect in the reaction system. This work provides a reference for the next step of actual production. [ABSTRACT FROM AUTHOR]

Reference 1 Kong D., Zhou Z., Song S., Feng S., Lian M., Jiang R. Preparation of Poly Aluminum-Ferric Chloride (PAFC) Coagulant by Extracting Aluminum and Iron Ions from High Iron Content Coal Gangue. SEM image of the gangue" was lost. Preparation of Poly Aluminum-Ferric Chloride (PAFC) Coagulant by Extracting Aluminum and Iron Ions from High Iron Content Coal Gangue. [Extracted from the article]

Efficient and selective removal of 90Sr is an important process for the safe use of nuclear energy. Herein, we investigate and assess the Sr2+ adsorption properties of a metal-organic framework UiO-66-(COOH)2 functionalized by non-bonded carboxylic groups. This MOF is an exciting class of free carboxylic functionalized MOFs that combine chemical stability with gas sorption, dye elimination, and conductivity. Specifically, we show that uniformly distributed carboxyl and water stability make it accessible for loading Sr2+ without structural changes. The FTIR spectroscopy, PXRD analysis, XPS, and SEM-EDS studies show excellent stability as well as the strong affinity between -COOH active site and Sr2+. This strong coordination interaction guarantees a high adsorption capacity of 114 mg g−1 within 5 h (pH 5 and 298 K). Combined kinetic and thermodynamic studies show that the surface complexation is strong chemisorption and cost-effective spontaneous process (ΔG = −5.49 kJ mol−1~−2.16 kJ mol−1). The fact that UiO-66-(COOH)2 not only possesses a high adsorption capacity, but also enables selectivity to Sr2+ in the presence of similar radius ions Na+ and K+, prefigures its great potential for the practical treatment of radioactive Sr2+ in polluted water. [ABSTRACT FROM AUTHOR]

Extracting valuable elements from coal gangue is an important method for the utilization of coal gangue. In order to obtain the suitable technological conditions and the acid leaching kinetic model of leaching aluminum and iron ions from high-iron and low-aluminum coal gangue, the effects of calcination temperature, calcination time, and acid types on the leaching results of aluminum and iron ions are studied. The results show that when the gangue is calcined at 675 °C for 1 h, then the calcined gangue powder is leached by 6 mol/L hydrochloric acid at 93 °C for 4 h, the leaching ratio of iron ions is more than 90%, and that of aluminum ions is more than 60%. Furthermore, the acid leaching kinetic equations at 30 °C, 50 °C, 70 °C, and 90 °C are studied by three kinetic models, and the apparent activation energies of the reactions are calculated by the Arrhenius formula. The results show that the leaching behavior of aluminum and iron ions conformed to the "mixing control" model equation: "(1 − x)−1/3 − 1 + 1/3ln(1 − x) = kt + b". The apparent activation energies of aluminum and iron ions are 55.5 kJ/mol and 55.8 kJ/mol, respectively. All these indicate that the acid leaching process is controlled by the "mixing control". [ABSTRACT FROM AUTHOR]

Ulcerative colitis (UC) is a relapsing and remitting inflammatory disease. Probiotics have a potential beneficial effect on the prevention of UC onset and relapse in clinical trials. Lactobacillus rhamnosus GG (L. rhamnosus GG) have shown clinical benefits on UC patients, however, the precise mechanisms are unknown. The aim of this study is to explore the effect of extracellular vesicles released from L. rhamnosus GG (LGG-EVs) on dextran sulfate sodium (DSS)-induced colitis and propose the underlying mechanism of LGG-EVs for protecting against colitis. The results showed that LGG-EVs could prevent colonic tissue damage and shortening of the colon (p < 0.01), and ameliorate intestinal inflammation by inhibiting TLR4-NF-κB-NLRP3 axis activation. Consistently, the pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, IL-2) were suppressed effectively upon LGG-EVs treatment (p < 0.05). The 16S rRNA sequencing showed that LGG-EVs administration could reshape the gut microbiota in DSS-induced colitis mice, which further alters the metabolism pathways of gut microbiota. These findings propose a novel perspective of L. rhamnosus GG in attenuating inflammation mediated by extracellular vesicles and offer consideration for developing oral gavage of LGG-EVs for colitis therapies. [ABSTRACT FROM AUTHOR]

Biochar is a kind of carbon-rich material formed by pyrolysis of biomass at high temperature in the absence or limitation of oxygen. It has abundant pore structure and a large surface area, which could be considered the beneficial characteristics for electrodes of microbial electrochemical systems. In this study, reed was used as the raw material of biochar and six biochar-based electrode materials were obtained by three methods, including one-step biochar cathodes (BC 800 and BC 700), biochar/polyethylene composite cathodes (BP 5:5 and BP 6:4), and biochar/polyaniline/hot-melt adhesive composite cathode (BPP 5:1:4 and BPP 4:1:5). The basic physical properties and electrochemical properties of the self-made biochar electrode materials were characterized. Selected biochar-based electrode materials were used as the cathode of sediment microbial electrochemical reactors. The reactor with pure biochar electrode (BC 800) achieves a maximum output power density of 9.15 ± 0.02 mW/m2, which increases the output power by nearly 80% compared with carbon felt. When using a biochar/polyaniline/hot-melt adhesive (BPP 5:1:4) composite cathode, the output power was increased by 2.33 times. Under the premise of ensuring the molding of the material, the higher the content of biochar, the better the electrochemical performance of the electrodes. The treatment of reed powder before pyrolysis is an important factor for the molding of biochar. The one-step molding biochar cathode had satisfactory performance in sediment microbial electrochemical systems. By exploring the biochar-based electrode, waste biomass could be reused, which is beneficial for the environment. [ABSTRACT FROM AUTHOR]

Object detection is an essential computer vision task that aims to detect target objects from an image. The traditional models are insufficient to generate a high-quality anchor box. To solve the problem, we propose a novel joint model called guided anchoring Region proposal networks and Cascading Grid Region Convolutional Neural Networks (RCGrid R-CNN), enhancing the ability of object detection. Our proposed model design is a joint object detection algorithm containing an anchor-based and an anchor-free branch in parallel and symmetry. In the anchor-based, we use nine-point spatial information fusion to obtain better anchor box location and introduce the shape prediction method of Guided Anchoring Region Proposal Networks (GA-RPN) to enhance the accuracy of the predicted anchor box. In the anchor-free branch, we introduce the Feature Selective Anchor-Free module (FSAF) to reduce the overlapping anchor boxes to obtain a more accurate anchor box. Furthermore, inspired by cascading theory, we cascade the new-designed detectors to improve the ability of object detection by setting a gradually increasing Intersection over Union (IoU) threshold. Compared with typical baseline models, we comprehensively evaluated our model by conducting experiments on two open datasets: Pascal VOC2007 and COCO2017. The experimental results demonstrate the effectiveness of RCGrid R-CNN in producing a high-quality anchor box. [ABSTRACT FROM AUTHOR]

Joint named entity recognition and relation extraction is an essential natural language processing task that aims to identify entities and extract the corresponding relations in an end-to-end manner. At present, compared with the named entity recognition task, the relation extraction task performs poorly on complex text. To solve this problem, we proposed a novel joint model named extracting Entity-Relations viaImproved Graph Attention networks (ERIGAT), which enhances the ability of the relation extraction task. In our proposed model, we introduced the graph attention network to extract entities and relations after graph embedding based on constructing symmetry relations. To mitigate the over-smoothing problem of graph convolutional networks, inspired by matrix factorization, we improved the graph attention network by designing a new multi-head attention mechanism and sharing attention parameters. To enhance the model robustness, we adopted the adversarial training to generate adversarial samples for training by adding tiny perturbations. Comparing with typical baseline models, we comprehensively evaluated our model by conducting experiments on an open domain dataset (CoNLL04) and a medical domain dataset (ADE). The experimental results demonstrate the effectiveness of ERIGAT in extracting entity and relation information. [ABSTRACT FROM AUTHOR]

Poly aluminum-ferric Chloride (PAFC) is a new type of high efficiency coagulant. In this study, high iron type gangue is used as a main raw material. It is calcined at 675 °C for 1 h and 3% CaF 2 is added to the calcined powder and reacted with 20% hydrochloric acid at 93 °C for 4 h. The leaching ratio of aluminum ions is 90% and that of iron ions is 91%. After Fe 2+ ions are oxidized in the filtrate, CaCO 3 is used to adjust the pH of the filtrate to 0.7. The microwave power is adjusted to 80 W and the filtrate is radiated for 5 min. After being aged for 24 h, PAFC product is obtained. The prepared PAFC is used to treat mine water and compared with the results of PAC and PAF, the turbidity removal ratio of PAFC is 99.6%, which is greater than 96.4% of PAC and 93.7% of PAF. PAFC is a mixture with different degrees of polymerization. It demonstrates that extracting aluminum and iron ions from high iron content gangue to prepare PAFC by microwave is efficient and feasible.