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Hydrated vanadium oxide (V 2 O 5 ·nH 2 O) is promising cathode candidates for aqueous rechargeable Zn-ion batteries (ZIBs) owing to its high theoretical specific capacity, abundant resources and environmentally friendly. However, the higher charge density of Zn2+ lead to its structural instability, cyclic degradation and sluggish Zn2+ diffusion kinetics. Herein, rare earth metal ions intercalated into the interlayer of V 2 O 5 ·nH 2 O materials (abbreviated as RE-VOH) are successfully synthesized to expand interlayer spacing and stabilize the layered structure via a simple sol-gel method, among, the yttrium ion intercalated V 2 O 5 ·nH 2 O (Y–VOH) exhibits a honeycomb porous microstructure and a remarkably enlarged interlayer distance (13.6 Å), which can not only increase the contact area between the electrode material and the electrolyte but also offer rapid diffusion channel for Zn2+. Meanwhile, the problem of vanadium dissolution of cathode materials is inhibited by the electrolyte additive strategy through adding suitable vanadium oxide sol to aqueous electrolyte, furthermore, the zinc anode modification strategy in electroplating process inhibits the formation of zinc dendrites. Benefitting from the synergistic effect of modification design for the ZIBs systems of cathode, electrolyte and anode, the overall electrochemical performance of Y–VOH electrode is significantly improved, delivering a large specific capacity of 337 mAh g−1 at the current density of 500 mA g−1 and excellent rate capability of 170 mAh g−1 at 10 A g−1, along with an outstanding capacity retention of 90 % over 3000 cycles. Additionally, systematical ex situ characterizations prove the (de)intercalation reversibility of Zn2+ storage mechanism for the Y–VOH cathode. This research may provide a new way for exploiting high performance vanadium-based materials for aqueous ZIBs. • Rare earth metal ion pre-intercalation expands layer spacing and enhances ion transfer kinetics of V 2 O 5 ·nH 2 O. • The dual strategies of electrolyte additive and zinc anode modification improves cycling stability. [ABSTRACT FROM AUTHOR]

Compound faults diagnosis of locomotive bearings are still a challenge especially when the multi-fault impulses share the common resonant frequency. In this paper, an adaptive filtering enhanced windowed correlated kurtosis (WCK) method is proposed to isolate and identify each fault mode. A concept termed flexible analytical wavelet transform (FAWT) spectrum is defined to construct proper FAWT basis such that high signal-to-noise (SNR) is obtained in the filtered signal. Further, WCK is applied on the denoised signals to successively isolate each fault mode and determine the defects number. The performance of the proposed method is validated via analyzing experiment measurements from the locomotive bearings subjected to two local roller defects and three local outer race damages. • Flexible analytical wavelet transform spectrum defined for adaptive filtering. • Windowed correlated kurtosis algorithm is proposed for identifying each fault mode. • The effectiveness of the method is tested by experimental measurements. [ABSTRACT FROM AUTHOR]

To reduce the ship roll motion, an adaptive robust fin controller based on a feedforward neural network is proposed. The dynamics of the fin actuator is considered in the plant of a roll-fin cascaded system with uncertainties which refer to as the modeling errors and the environmental disturbance induced by waves. An on-line feedforward neural network is constructed to account for the uncertainties. Lyapunov design is employed to obtain the fin stabilizer with guaranteed robustness. Simulation results demonstrate the validity of the controller designed and the superior performance over a conventional PD controller. [ABSTRACT FROM AUTHOR]

Penetrating brain injury is 1 type of traumatic brain injury. Brain abscess is a common complication after penetrating brain injury, and fragments increase the risk of occurrence of brain abscess. It is uncommon to see the migration of bone fragments in the brain in clinical cases. We report a rare case of brain abscess with migration of bone fragments after traumatic brain injury. [ABSTRACT FROM AUTHOR]

• The results show that the maximum absorption rate at the resonant wavelength increases from 0.0109 corresponding to Fermi energy level 0.2 ev to 0.1276 corresponding to 0.8 ev, which is improved by nearly 12 times. • When the other parameters are unchanged and the relaxation time is increased from 0.1 ps to 1.0 ps, the maximum value of the absorption peak increases from 0.0162 to 0.1155. • This paper also compares the double-symmetric "arrow" type structure on the basis of this structure. The absorption spectrum of this structure shows a double peak phenomenon, which can achieve the purpose of selective absorption. The research results have certain guiding significance and important reference value for the design of graphene-based programmable perfect terahertz absorbers, and can be applied to the fields of label-free biomedical sensing, photodetectors and photonic device design. A tunable selective absorber consisting of a periodic "arrow" shaped graphene array that operates in the far infrared and terahertz range is proposed. It is achieved by depositing a set of graphene "arrow" shaped ribbon on a SiO 2 dielectric spacer layer. The absorption characteristics of the structure are investigated by the Finite Difference Time Domain (FDTD) method. The results show that the maximum pure absorption rate at the resonant wavelength increases from 1.09% corresponding to Fermi energy level 0.2 eV to 12.76% corresponding to 0.8 eV, which is improved by nearly 12 times. Moreover, the relaxation time is increased from 0.1 ps to 1.0 ps with the other parameters are unchanged, and the maximum value of the pure graphene absorption peak increases from 1.62% to 11.55%. Moreover, the resonance wavelengths of the absorber possess angle insensitivity, nevertheless the absorption peak intensity is sensitive to the angle of incidence. In addition, this paper also compares the double-symmetric "arrow" shaped structure on the basis of this structure. The absorption spectrum of the structure shows a double peak phenomenon, which can achieve the purpose of selective absorption. The research results have certain guiding significance and important reference value for the design of next–generation graphene-based perfect terahertz absorbers, and the design can be applied to the fields of label-free biomedical sensing, photodetectors and photonic devices. [ABSTRACT FROM AUTHOR]

In this study, the influence of ultrasound-assisted resting at different power on the rheological properties, water distribution and structural characteristics of dough with 50 % surimi as well as the texture, cooking and microstructure characteristics of the surimi-wheat noodles were investigated. Compared with the fermentation control (FC) noodles, the microstructure, cooking and texture characteristics of noodles (≤24.00 W/L) were significantly (p < 0.05) improved after ultrasonic treating. As the increasing of ultrasonic power, compared to FC, the creep strain, recovery strain, semi-bound water, and free sulfhydryl (SH) contents of surimi-wheat dough decreased at first and then increased significantly (p < 0.05). The α-helix and β-turn content of dough increased at first and then decreased after ultrasonic treatment, while the β-sheet was reversed. The surimi-wheat dough network structure was improved by ultrasonic treatment, with the densest and continuous pore size in 21.33 W/L, but the dough structure was broken and loose (>21.33 W/L), which consisted of the hardness, elasticity, chewiness, resistant and cooked quality of surimi-wheat noodles. This work elucidated the effect of ultrasonic power on the performance of surimi-wheat dough, and the optimal ultrasound power was obtained, thereby improving the nutritional properties and the quality of surimi-wheat noodles. [ABSTRACT FROM AUTHOR]

• A fault signal detection method based on object detection is proposed. • Using the fault feature regions (FFRs) to detect the bearing fault impact features. • Realizing the compound fault diagnosis of bearing with single fault data. • Showing the superior performance of accuracy and efficiency of fault diagnosis. Bearing faults of rotating machinery are common compound faults, and diverse fault categories are coupled, which makes it challenging to achieve state monitoring. For this purpose, a fault diagnosis method based on fault feature region (FFR) detection for bearings is proposed. The key point is an FFR proposal network for several regions with fault features from training samples. This process only uses the single fault data. These obtained regions are used as the training dataset of a module based on a deep belief network. In the application, if the output probabilities satisfy the discrimination terms, then an untrained compound fault state is output. Furthermore, the bearing compound fault dataset is employed to assess the diagnosis performance. The results reveal that the diagnosis accuracy of compound faults and the overall accuracy exceeds 80%. This fascinating discovery proves the superiority of the proposed approach to achieving compound fault diagnosis for rolling bearings. [ABSTRACT FROM AUTHOR]

• Quasi-core-shell APP vertically deposited by thermochromic Salen lamellas was bioinspired designed. • MAPP@Salen disclosed an unprecedentedly low triggering temperature of 120 °C and time of 1 s. • An isomerization of Salen to cis-keto and vertically alignment accounted for ultra-sensitiveness. • Model coating with MAPP@Salen presented a 0.3 s responsive time at 250 oC and remote monitoring. • Fire-alarming coating possessed an improved fire protection and moisture resistance. Aiming to integrate a low-temperature, ultrasensitive and wireless remote-monitoring fire alarming with a fire suppression into a commercialized system, in view of a heat-induced tailored isomerization of Salen molecules and sunflower configuration for a heat capturing, we constructed a quasi-core-shell MAPP@Salen with silaned ammonia polyphosphate guiding a vertical deposition of Salen lamellas assembly. Resultantly, MAPP@Salen demonstrated an ultralow triggering temperature of 120 °C and 1 s time at 250 oC with a remarkable color from yellow to dark red. A Salen isomerization and its vertical alignment on MAPP accounted for an ultra-sensitiveness feature. A model acrylic coating with MAPP@Salen presented a 0.3 s responsive time at 250 °C as well as instant (0.5 s) and unstopped warning once flame approached. A wireless signal communication system via a color recognition algorithm and 4 G IoT was realized. Additionally, the coating provided >10 min and ultrastrong intumescent fire protection via a Salen-participative charring optimization as well as well-persevered structural integrity after a long-term water attack. The fire-alarming capability was retained as well. This work pertaining to a bio-inspired hierarchical assembly integrates a low-temperature ultra-sensitive fire alarming and an optimized fire resistance for commercial all-time-scale fire retardants in multi-scenario universal applications. [Display omitted] [ABSTRACT FROM AUTHOR]

• A Bi-directional deep belief network is developed for bearings fault diagnosis. • Quantum genetic algorithm is utilized to get the optimal model. • The effectiveness of the proposed method is verified on a printing press platform. Intelligent fault diagnosis model based on machine learning algorithm has extensive application, while the unsatisfied training data quality leads to the lower accuracy of intelligent fault diagnosis and inferior generalization performance. To address this problem, a method called Bi-directional deep belief network (Bi-DBN) is developed for fault diagnosis of rolling bearings. The forward training part of Bi-DBN can learn the fault features from the original vibration signals first, and then the reverse generation part synthesizes samples according to the weight sharing by the forward training part. The noise time-shift layer is innovatively introduced to reduce the similarity between the synthesized sample and the original sample. Finally, Quantum genetic algorithm (QGA) is applied to optimize the key parameters of Bi-DBN to improve the feature learning efficiency. The experimental results of rolling bearing signals indicate that the developed method significantly limits the effect of training data quality on the diagnosis accuracy. [ABSTRACT FROM AUTHOR]

Ni catalysts with preferred orientation and microsphere were fabricated by a facile one-step pulsed voltage electrodeposition (PVE) method, while the crystal plane orientation and catalytic activity for borohydride oxidation reaction (BOR) were researched systematically. The results indicate that adjusting pulse anode potential can effectively regulate the morphology and crystal plane preferred orientation of Ni catalysts. The optimal Ni-PVE 0.15 catalyst exhibits the highest catalytic activity, stability, and fuel efficiency to BOR. The improvement of catalytic activity of Ni and fuel efficiency is attributed to the more exposure of the (220) crystal plane, which blocks the competing hydrogen evolution reaction (HER), increases the intrinsic activity of the catalytic sites to BOR, and strengthens the adsorption of escaping hydrogen to further electrooxidation. Meanwhile, the no-cracks feature of the microsphere increases the active sites and avoids the shedding of catalysts. The derived insights are important for the design of efficient nickel catalysts for practical applications of direct borohydride fuel cells. [Display omitted] • The microsphere Ni catalyst with a highly preferred orientation of (220) plane was prepared by pulse electrodeposition. • Pulsed anode potential can control the morphology and structure of Ni. • The (220) crystal plane benefits the adsorption of borohydride, capture of H 2 , and inhibition of HER. • Ni-PVE 0.15 catalyst demonstrates excellent activity to BOR with high stability and efficiency. [ABSTRACT FROM AUTHOR]

The effects of the differently charged anions, NaCl, NaBr, NaI, Na 2 SO 4 , and Na 3 PO 4 on the gel properties and structure of the fucoidan/κ-carrageenan mixed gel (FC) were investigated using the rheometer, texture analyzer, LF-NMR, Cryo-SEM, FT-IR, and XRD. At a certain concentration, Cl− and Br− could stabilize the helical conformation of the gel through electrostatic shielding. The addition of SO 4 2− and PO 4 3− would reduce the strength of the gel. And I− would soften the gel. With increasing anion concentration, the electrostatic repulsion between FUC and KC was gradually enhanced. The FUC dispersions remained liquid after the addition of anions, while FC gelled depending on the type and concentration of anions. The elastic modulus increased with increasing concentration of NaCl and NaBr, but decreased with increasing concentration of NaI, Na 2 SO 4 , and Na 3 PO 4. Moreover, the addition of anions promoted the water migration of FC, as reflected by the T 23 relaxation time changing from high to low and the significantly higher migration of NaCl and NaBr than NaI and Na 2 SO 4. The pores of the gel microstructure change from disordered to uniform. The FT-IR and XRD results were well related to the structural changes. There is electrostatic repulsion between anion and FC, and the binding ability of FC to monovalent anions and trivalent anions is better than that of divalent anions. Overall, this study could provide a theoretical basis for the design and development of FUC-based gels. [Display omitted] • Different anions affected the formation of fucoidan/κ-carrageenan mixed gel. • Cl− and Br− promoted the formation of the gel network. • I− decreased the gel strength by the formation of flexible joints. • SO 4 2− and PO 4 3− reduced the connection areas between the molecules. [ABSTRACT FROM AUTHOR]

• Successfully developed a facile route to synthesize core-shell Bi@NC nanorods. • Core-shell Bi@NC nanorods were firstly applied as anode for MIBs. • Micropores in carbon matrix mitigate the large volume change of inner core Bi. • Excellent Mg storage performance, especially in rate performance. The rechargeable magnesium batteries are potentially applicable in large-scale energy storage systems because of the low costs and rich sources. But the alternative anodes for magnesium ion batteries have not been fully developed. In this work, a novel bismuth-carbon composite with bismuth nanorods anchored in nitrogen-doped mesoporous carbon matrix (Bi@NC), was prepared as anode for magnesium ion batteries by carbonizing the dopamine-coated bismuth metal precursors. The matrix facilitated the magnesiation/de-magnesiation of bismuth due to its highly electronic conductive network. Moreover, it restrained the aggregation of bismuth nanorods and serves as a buffer layer to alleviate the mechanical strain of bismuth nanorods upon magnesium insertion/extraction. As the anode for magnesium ion batteries, the Bi@NC core-shell nanorods delivered a reversible capacity of 360 mAh g−1 at the current density of 100 mA g−1, and 87 % of the initial capacity was achieved after 100 cycles. The standout rate performance is 275 mAh g−1 at the current density of 1 A g−1. Such a good electrochemical property demonstrated the great application potential of Bi@NC as anode in magnesium ion batteries. [Display omitted] [ABSTRACT FROM AUTHOR]