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All‐solid‐state battery (ASSB) is a potential future energy storage technology to power the future world. However, the solid–solid contacts among the various components in ASSB often require a high stack pressure which is unrealistic in practical applications. Here it is shown that by carbon‐coating Sb2Se3 (Sb2Se3@C) nanorods, a record low stack pressure is attained, and the Sb2Se3@C electrode exhibits outstanding performance of 862 mAh g−1 over 50 cycles at 0.1 A g−1 when it is operated at 5 MPa stack pressure in an ASSB using LiIn anode and Li10Si0.3PS6.7Cl1.8 solid‐state electrolytes. Furthermore, a record high active material loading (the mass fraction of Sb2Se3@C being 0.7 in composite cathode) is achieved, and the Sb2Se3@C based ASSB delivers a reversible capacity of 2.6 mAh cm−2 at 0.1 A g−1 after 100 cycles. This work provides a strategy to significantly increase the cathode active material loading and dramatically reduce the stack pressure of ASSBs, which brings it one step closer toward the practical implementation of ASSBs for energy storage applications. [ABSTRACT FROM AUTHOR]

Magnetic fluid and magnetorheological fluid are two of the most effective magnetic media seals, yet the sealing effectiveness of both has not been compared systematically. To investigate the differences between magnetic fluid and magnetorheological fluid seals, a comparative experimental device is proposed to study the sealing mechanism and performance of the two sealing media at different temperatures. Numerical simulation is used to study the magnetic field distribution of the comparative experimental device and calculate the theoretical pressure resistance (PR) of the two sealing media, respectively. The correctness of the theoretical PR formula of the magnetic media seals with additional temperature coefficient is verified by the comparative experimental results. The results show that the number of resumptions of the magnetorheological fluid film decreases with increasing temperature, while the magnetic fluid film consistently undergoes only one recovery. In addition, the self-healing capability and PR of magnetorheological fluid seals are better than that of magnetic fluid seals, and it is less affected by temperature and has stronger temperature adaptability. [ABSTRACT FROM AUTHOR]

Unpiloted technology requires attitude measurement from global positioning system to adjust the moving direction of car. However, the measurement result from the satellites suffer from fluctuation, which reduces the control ability of system. Thus, we propose our novel algorithm. First, it builds double difference observation equation based the measurements from two satellites. Second, the least squares algorithm is utilized to calculate double difference integer ambiguity. Third, it constructs the length of baseline to calculate baseline vector, which improves the solution success rate of integer ambiguity and reduces frequency of mutation occurs in attitude angle solving process. Finally, baseline vector is employed to solve the attitude angle of unpiloted car. The extensive experimental results demonstrate that the success rate of the attitude reach 95% within 2° of error under the constraint of the baseline, and the error of the attitude is less than 1° under the dynamic condition. [ABSTRACT FROM AUTHOR]

The Industrial Metaverse provides unparalleled prospects for increasing productivity and efficiency across multiple sectors. As wireless sensor networks play an important role in data collection and transmission within this ecosystem, preserving context privacy becomes critical to protecting sensitive information. This paper investigates the issue of context privacy preservation for user validation via AccesSensor in the Industrial Metaverse and presents a technological method to address it. We explore the need for context privacy, look at existing privacy preservation solutions, and propose novel user validation methods that are customized to the Industrial Metaverse's access system. This method is evaluated on time-based efficiency, privacy method and bandwidth utilization. Our method performs better as compared to the DPSensor. Our research seeks to provide insights and recommendations for developing strong privacy protection methods in wireless sensor networks that operate within the Industrial Metaverse ecosystem. [ABSTRACT FROM AUTHOR]

Accretion of black holes at near-Eddington or super-Eddington rates represents the most powerful episode driving black hole growth, potentially occurring across various types of objects. However, the physics governing accretion and jet–disk coupling in such states remains unclear, primarily due to the difficulty in detecting associated jets, which may emit extremely weakly or exhibit episodic behavior. Only a few near/super-Eddington systems have demonstrated radio activity, and it remains uncertain whether jets exist and what their properties are in super-Eddington active galactic nuclei (AGNs) and ultraluminous X-ray sources. This uncertainty stems mainly from the complex radio emission mix, which includes contributions from jets, star formation activity, photoionized gas, accretion disk wind, and coronal activity. In this work, we conducted high-resolution, very long baseline interferometry observations to investigate jets in the highly accreting narrow-line Seyfert I system I Zw 1. Our observations successfully revealed small-scale jets (with a linear size of ∼45 pc) at both 1.5 and 5 GHz, based on the high radio brightness temperature, radio morphology, and spectral index distribution. Additionally, the parsec-scale jet observed in I Zw 1 displays a knotted morphology reminiscent of other sources accreting at similar rates. In summary, the high accretion rates and jet properties observed in the AGN I Zw 1 may support the AGN/X-ray binary analogy in this extreme state. [ABSTRACT FROM AUTHOR]

The IrRh@C ZIF-8 catalysts capable of oxidizing H 2 , CO, or a combination of the two is fabricated through the secondary high temperature annealing. Benefiting from the closely located single atom sites to the nanoparticles, CO on the metal nanoparticles could be efficiently removed, thus conferring the catalysts with excellent H 2 oxidation performance in CO presence that has not been possible before. This work opens up a new avenue to conquer the formidable poisoning issue of PEMFCs. [Display omitted] Nanosized Pt catalysts are the catalyst-of-choice for proton exchange membrane fuel cell (PEMFC) anode, but are limited by their extreme sensitivity to CO in parts per million (ppm) level, thereby making the use of ultrapure H 2 a prerequisite to ensure acceptable performance. Herein, we confront the CO poisoning issue by bringing the Ir/Rh single atom sites to synergistically working with their metallic counterparts. In presence of 1000 ppm CO, the catalyst represents not only undisturbed H 2 oxidation reaction (HOR) catalytic behavior in electrochemical cell, but also unparalleled peak power density at 643 mW cm−2 in single cell, 27-fold in mass activity of the best PtRu/C catalysts available. Pre-poisoning experiments and surface-enhanced Raman scattering spectroscopy (SERS) and calculation results in combine suggest the presence of adjacent Ir/Rh single atom sites (SASs) to the nanoparticles (NPs) as the origin for this prominent catalytic behavior. The single sites not only exhibit superb CO oxidation performance by themselves, but can also scavenge the CO adsorbed on approximated NPs via supplying reactive OH* species. We open up a new route here to conquer the formidable CO poisoning issue through single atom and nanoparticle synergistic catalysis, and pave the way towards a more robust PEMFC future. [ABSTRACT FROM AUTHOR]

To investigate the sealing mechanism and performance of the symmetric magnetic fluid seal (SMFS) with occlusal pole teeth (OPT), an experimental device was designed. The impact of magnetic fluid volumes and groove widths on the sealing mechanism and performance of the SMFS-OPT was investigated under different environments. Combining experimental results and numerical analyses, the applicability of the magnetic fluid sealing theoretical pressure resistance formula to SMFS-OPT is verified. The results show that low magnetic fluid volume and a large groove width prolong the differential pressure reduction process, thereby reducing the pressure resistance of the sealing device. Increasing the volume of the magnetic fluid increases the sealing device's self-healing rate but does not change the trend of the number of ruptures' impact on the pressure resistance. [ABSTRACT FROM AUTHOR]

[Display omitted] Healable electronic skins, an essential component for future soft robotics, implantable bioelectronics, and smart wearable systems, necessitate self-healable and pliable materials that exhibit functionality at intricate interfaces. Although a plethora of self-healable materials have been developed, the fabrication of highly conformal biocompatible functional materials on complex biological surfaces remains a formidable challenge. Inspired by regenerative properties of skin, we present the self-assembled transfer-printable liquid metal epidermis (SALME), which possesses autonomous self-healing capabilities at the oil–water interface. SALME comprises a layer of surfactant-grafted liquid metal nanodroplets that spontaneously assemble at the oil–water interface within a few seconds. This unique self-assembly property facilitates rapid restoration (<10 s) of SALME following mechanical damage. In addition to its self-healing ability, SALME exhibits excellent shear resistance and can be seamlessly transferred to arbitrary hydrophilic/hydrophobic curved surfaces. The transferred SALME effectively preserves submicron-scale surface textures on biological substrates, thus displaying tremendous potential for future epidermal bioelectronics. [ABSTRACT FROM AUTHOR]

To investigate the influence of temperature on the pressure transfer mechanism and failure mechanism for magnetic fluid seal (MFS) with opposite pole teeth (OPT), a sealing device with water circulation channel was designed. Sealing mechanism and performance of the sealing device at different temperatures were experimentally investigated under gas and vacuum environments, respectively, and comparison with the experimental results at normal temperature. Theoretical pressure resistance was calculated according to the theoretical pressure resistance formula for MFS with temperature coefficient. The results show that temperature affects the trend of pressure difference variation for the MFS-OPT. As temperature decreases, self-stability of the magnetic fluid film improves, while pressure resistance and self-healing capability of the MFS-OPT become more pronounced. [ABSTRACT FROM AUTHOR]

In the alkaline hydrogen evolution reaction (HER), the dissociation energy barrier of water, and the easy adsorption of OH on the catalyst are key factors that limit the catalytic activity. This work proposes a novel competing adsorption mechanism driven by dz2 electrons in the context of the alkaline HER. The high concentration of oxygen vacancies in Co doped SrRuO3 (V‐SRCO) results in the electron filling in the Ru 4dz2 orbital. Under alkaline conditions, the V‐SRCO exhibits a low overpotential of only 57.8 mV with a Tafel slope of 35 mV dec−1. Moreover, it exhibits sustained high activity for 60 h. The high HER activity of V‐SRCO can be attributed to the presence of a single electron in the dz2 orbital, which reduces the energy barrier for water dissociation. More importantly, the active electrons in the dz2 orbital can inject into the antibonding orbitals of OH, creating an unfavorable environment for OH adsorption on the catalyst. This work provides favorable conditions for efficient HER. [ABSTRACT FROM AUTHOR]

Highly efficient near‐infrared (NIR) emitters have significant applications in medical and optoelectronic fields, but the development stays a great challenge due to the energy gap law. Here, we report two NIR phosphorescent Ir(III) complexes which display emission peaks around 730 nm with a narrow full width at half maximum of only 43 nm. Therefore, pure NIR luminescence can be obtained without having a very long emission wavelength, thus alleviating the restriction of the energy gap law, and obtaining impressively high photoluminescence quantum yield up to 0.70. More importantly, the pure NIR organic light‐emitting diode (OLED) fabricated by the solution‐processed mothed shows outstanding device performance with the highest external quantum efficiency of 16.43 %, which sets a new record for solution‐processed NIR‐OLEDs based on different emitters. This work sheds light on the development of Ir(III) complexes with narrowband emissions as highly efficient pure NIR‐emitters. [ABSTRACT FROM AUTHOR]

Highly efficient near‐infrared (NIR) emitters have significant applications in medical and optoelectronic fields, but the development stays a great challenge due to the energy gap law. Here, we report two NIR phosphorescent Ir(III) complexes which display emission peaks around 730 nm with a narrow full width at half maximum of only 43 nm. Therefore, pure NIR luminescence can be obtained without having a very long emission wavelength, thus alleviating the restriction of the energy gap law, and obtaining impressively high photoluminescence quantum yield up to 0.70. More importantly, the pure NIR organic light‐emitting diode (OLED) fabricated by the solution‐processed mothed shows outstanding device performance with the highest external quantum efficiency of 16.43 %, which sets a new record for solution‐processed NIR‐OLEDs based on different emitters. This work sheds light on the development of Ir(III) complexes with narrowband emissions as highly efficient pure NIR‐emitters. [ABSTRACT FROM AUTHOR]

This paper presents an improved quantum dialogue protocol based on the HHL algorithm. In this protocol, Alice and Bob want to transmit their classical information to each other. Combining the HHL algorithm and quantum linear equation ensures that eavesdroppers cannot steal the data of communicators. In addition, communicators will connect come HHL quantum circuit constructed in this scheme with the swap test circuit to calculate the solution rather than directly measuring the result, which can improve the solution speed. Security analysis shows that this scheme is more secure than other general quantum dialogue schemes, and it can realize information protection in extreme cases, with good security and higher transmission efficiency. [ABSTRACT FROM AUTHOR]

Exploring the semiconductor materials with suitable gap and chemical stability is the key to developing solar-blind ultraviolet photodetectors with high stability, responsivity, and detectivity. However, available materials are limited currently, hindering the development of solar-blind detectors greatly. Rare earth oxides (Yb2O3) have the bandgap and high-dielectric constants suitable for solar-blind detection, but its potential of being applied to broadband gap semiconductors has not been deeply studied. Therefore, to activate the semiconductor characteristics of Yb2O3, this work builds a p-Gr/i-Yb2O3/n-Si heterojunction solar-blind ultraviolet photodetector by introducing single-layer graphene. Through tests, this device has an absorption cutoff wavelength of 271 nm, which can almost cover the entire solar-blind ultraviolet band, and a high responsivity of 9.78 mA/W under 0 V bias with the rise and fall time as short as 87 and 73 ms, respectively. This work not only prepares a high-performance solar-blind UV photodetector but also presents the potential application of Yb2O3 in the solar-blind ultraviolet light detection. The high-dielectric performance of rare earth oxides makes it expected to be used for the photoelectric chip unit in future integrated circuit. [ABSTRACT FROM AUTHOR]

We present radio very long baseline interferometry (VLBI) and X-ray studies of the starburst galaxy NGC 3628. The VLBI observation at 1.5 GHz reveals seven compact (0.7−7 pc) radio sources in the central ∼250 pc region of NGC 3628. Based on their morphology, high radio-brightness temperatures (105–107 K), and steep radio spectra, none of these seven sources can be associated with active galactic nuclei (AGNs); instead, they can be identified as supernova remnants (SNRs), with three of them appearing consistent with partial shells. Notably, one of them (W2) is likely a nascent radio supernova (SN) and appears to be consistent with the star formation rate of NGC 3628 when assuming a canonical initial mass function. The VLBI observation provides the first precise measurement of the diameter of the radio sources in NGC 3628, which allow us to fit a well-constrained radio surface brightness—diameter (Σ– D) correlation by including the detected SNRs. Furthermore, future VLBI observations can be conducted to measure the expansion velocity of the detected SNRs. In addition to our radio VLBI study, we analyze Chandra and XMM-Newton spectra of NGC 3628. The spectral fitting indicates that the SNR activities could well account for the observed X-ray emissions. Along with the Chandra X-ray image, it further reveals that the X-ray emission is likely maintained by the galactic-scale outflow triggered by SN activities. These results provide strong evidence that SN-triggered activities play a critical role in generating both radio and X-ray emissions in NGC 3628. [ABSTRACT FROM AUTHOR]

This article presents a dual‐band filtering power amplifier (DB‐FPA) with extended passband bandwidths and wide stopband rejection, which is helpful in reducing the number of microwave components in the dual‐band radio frequency front end, resulting in compact circuit size and low loss. In the designed DB‐FPA, a wideband low‐pass filter is applied as the input matching network (IMN) to provide wideband impedance matching and good stopband rejection, while a dual‐band filtering impedance transformation is adopted as the output matching network (OMN) to provide dual‐band impedance matchings and filtering responses simultaneously. Specifically, the IMN is constructed by high‐impedance transmission‐line sections and low‐impedance open‐circuit stubs. The OMN is designed based on the specific external quality factors and coupling coefficients during two bands, resulting in dual‐band impedance transformations and dual‐band filtering responses. Then, based on the above IMN and OMN, the design procedure of the presented DB‐FPA is summarised. To verify the proposed idea, a novel DB‐FPA has been fabricated and measured. During the two frequency bands, the measured maximum power added efficiencies are 55.11% and 47.78% within 33.0 dBm input power, while the measured peak gains are 15.4 and 14.0 dB within 15.0 dBm input power. [ABSTRACT FROM AUTHOR]

This paper investigates the failure mechanism of a divergent magnetic fluid seal (MFS) with staggered pole teeth (SPT). By pole teeth, we mean the teeth machined on the inner ring surface of the pole pieces, which have a magnetic field gathering effect. A sealing apparatus capable of directly visualizing the surface deformation of the magnetic fluid film is developed, and the sealing mechanism is studied through experiments. The magnetic field distribution of the sealing apparatus is numerically analyzed to calculate its theoretical value, and this is compared against the experimental observations. The impacts of the eccentricity distance of the axial pole teeth and the addition of magnetic insulation materials on the pressure resistance of the MFS–SPT structure are investigated. The results show that, during the pressure loading process, the magnetic fluid moves to the low-pressure side. When the seal fails, micro-leakage and complete leakage occur successively in the MFS–SPT structure. There is good agreement between the experimental and theoretical pressure resistance of a divergent MFS–SPT. As the eccentricity distance of the axial pole teeth increases, the pressure resistance of the divergent MFS–SPT is enhanced. The sealing performance of the divergent MFS–SPT structure is improved when a magnetic insulation material is added to the grooves of the axial teeth. [ABSTRACT FROM AUTHOR]

In recent years, the behavior recognition technology based on Wi-Fi devices has been favored by many researchers. Existing Wi-Fi-based human behavior recognition technology mainly uses classification algorithms to construct classification models, which has problems such as inaccurate behavior segmentation, failure to extract deep-level features from the original data and design classification models matching the proposed features in the process of behavior recognition. In order to solve above problems, this paper proposes a window variance comparison method by combining the adaptive thresholds calculated to achieve effective segmentation of multiple discontinuous human behaviors, then uses the short-time Fourier algorithm to extract time-frequency features of individual behavior, and extracts the graph structure data from the autocorrelation matrix of time-frequency features and the features themselves. A graph neural network is built for behavior recognition. The experimental results show that the segmentation accuracy of the behavior segmentation method in the two scenes is 0.964 and 0.993, which is better than the existing threshold-based behavior segmentation methods. In addition, this paper extracts graph structure data by spectral energy change method and builds behavior recognition model by using graph neural network, and the recognition accuracy is significantly improved compared with the traditional classification algorithm. [ABSTRACT FROM AUTHOR]

Sensor fusion is a technique that combines information from multiple sensors in order to improve the accuracy and reliability of the data being collected. In the context of teleoperation control of an anthropomorphic robotic arm, sensor fusion technology can be used to enhance the precise control of anthropomorphic robotic arms by combining data from multiple sensors, such as cameras, data gloves, force sensors, etc. By fusing and processing this sensing information, it can enable real-time control of anthropomorphic robotic arms and dexterous hands, replicating the motion of human manipulators. In this paper, we present a sensor fusion-based teleoperation control system for the anthropomorphic robotic arm and dexterous hand, which utilizes a filter to fuse data from multiple sensors in real-time. As such, the real-time perceived human arms motion posture information is analyzed and processed, and wireless communication is used to intelligently and flexibly control the anthropomorphic robotic arm and dexterous hand. Finally, the user is able to manage the anthropomorphic operation function in a stable and reliable manner. We also discussed the implementation and experimental evaluation of the system, showing that it is able to achieve improved performance and stability compared to traditional teleoperation control methods. [ABSTRACT FROM AUTHOR]

An indoor vibrational dissolution scouring test was designed to investigate the effects of vibrational frequency, vibrational acceleration, environmental temperature, and dissolution medium on the dissolution characteristics of cement-stabilized macadam base material during water erosion. The results showed that the dissolution damage effect exists in cement-stabilized macadam, and dissolution is an important evaluation index of its base failure. The amount of calcium ion (Ca2+) dissolution and pH of cement stabilized gravel increased with increasing vibrational time. When the vibrational frequency was in the range of 80–180 Hz , the amount of dissolved Ca2+ and the pH of the solution first increased, and then decreased with the vibrational frequency. The Ca2+ concentration and pH of the solution reached their maximum at 140 Hz for 10 h. Of the four vibrational dissolution factors considered, vibrational acceleration produced the largest degree of dissolution of cement-stabilized macadam. The leached Ca2+ concentration increased with increasing temperature of the dissolution medium and the concentration of ammonium chloride (NH4Cl) solution, while increasing pH decreased dissolution. [ABSTRACT FROM AUTHOR]

Atractylodes macrocephala Koidz (AMK) is an expensive edible Chinese herb with medicinal properties. Its economic value and medicinal properties are closely related to its geographical origin. In this study, a method based on stable isotopes and multiple elements combined with chemometrics was developed to identify the geographical origin of AMK. Five stable isotope ratios, including δ2H, δ18O, δ13C, δ15N, and δ34S, and 41 elements in 281 AMK samples from 10 regions were analyzed. An analysis of variance of stable isotope ratios and elements revealed that the δ2H, δ18O, Mg, Ca, and rare‐earth element concentrations in AMK from different geographical regions were significantly different. Orthogonal partial least squares discriminant analysis proved that Ca, K, Mg, and Na can be used for classifying (variable importance >1) and accurately identifying AMK from Panan, Xianfeng, and other areas with 100% discrimination accuracy. In addition, we achieved a good identification of protected geographic indication products of similar quality. This method realized the geographical discrimination of AMK from different producing areas and could potentially control the fair trade of AMK. Practical Application: The quality of AMK is highly dependent on its geographical origin. Confusion over the origin of AMK impacts consumer rights. This study developed an accurate and effective classification method based on stable isotopes and multiple elements to ascertain the geographical origin of AMK, thereby providing an effective method for determining its quality. [ABSTRACT FROM AUTHOR]

With the ongoing progress in updating electrode materials and electrolyte components, the performance of lithium‐ion batteries (LIBs) has been greatly improved in the past decades. Specifically, density functional theory (DFT) calculations have emerged as a convenient and reliable strategy, especially to comprehend the origin for the improved electrochemical performances induced by certain reagent. Herein, DFT calculations have been utilized to analyze the plausibility of electrolyte additives for six groups of heterocyclic molecules (including N‐, O‐, S‐, N,O‐, S,N/O‐containing cyclic structures, and other cyclic ones, with 110 molecules in total). VC was used as the reference, as we aim to develop the additives with higher reductivity and high‐voltage stability etc. than that of VC. With the filter of LUMO, HOMO, HOMO‐LUMO gap, and Li+ binding energies, 6 molecules were finally screened out. The synthesis of one sulfate‐containing structure (i. e. 85) and its improved electrochemical performance of LIBs supports the theoretical prediction. [ABSTRACT FROM AUTHOR]

Quantum teleportation is a hot topic of extensive research at present, and bidirectional quantum teleportation is one of the important research directions. In this paper, we propose a scheme to realize controlled bidirectional quantum teleportation by using a six-particle as the quantum channel. In this scheme, the communication parties Alice and Bob need to cooperate to send and receive unknown arbitrary particle states, which can’t achieve the purpose alone. During the transmission, Alice and Bob only need to perform simple Bell state measurement and single-particle measurement, and the measurement steps are few. Finally, the purpose can be achieved by performing some appropriate unitary transformations. We validate the scheme on the IBM Quantum Experiment platform and the feasibility by data. In terms of security, we discuss the method of ensuring communication security when this scheme is subjected to external and internal attacks. Finally, we compare it with other bidirectional quantum teleportation schemes, our scheme consumes fewer quantum resources and classical resources, operates fewer times, and has higher transmission efficiency, which fully highlights the advantages of this scheme. [ABSTRACT FROM AUTHOR]

Herein, a divergent stepped magnetic fluid seal with a single magnetic source is designed to improve the pressure capability of ordinary magnetic fluid seal under small clearance. To explore the effects of injection volume, axial clearance, radial clearance, axial tooth number and radial tooth number on divergent stepped magnetic fluid seal, the pressure capability of magnetic fluid seal with an ordinary structure was comparatively analyzed through experimentation. According to the experimental results, there is no leakage or ejection of magnetic fluid from the sealing device when the critical pressure of divergent stepped magnetic fluid sealing is reached. The divergent stepped magnetic fluid seal structure performs better in pressure resistance the magnetic fluid seal with an ordinary structure. Also, the existence of axial teeth in the stepped magnetic fluid sealing structure leads to an increase in polar teeth, which not only extends the leakage path of the sealing medium but also exacerbates energy loss for the magnetic fluid carried by the sealed medium. This is effective in improving the pressure resistance of the magnetic fluid seal. When the axial tooth number reaches or exceeds the radial tooth number and the axial clearance falls below the radial clearance, the divergent stepped magnetic fluid seal with small clearance has a pressure capability that is 4.1–6 times higher than the critical pressure of ordinary magnetic fluid seal. When the axial clearance exceeds the radial clearance and the axial tooth number falls below the radial tooth number, the divergent stepped magnetic fluid seal has a critical pressure that is 1.9–3.6 times higher than that of conventional magnetic fluid seal. [ABSTRACT FROM AUTHOR]

The optimal supplementation of lipid nutrients in the diet showed crucial physiological functions in gonadal development and maturation in adult female aquatic animals. Four isonitrogenous and isolipidic diets with no extra lecithin supplementation (control), 2% soybean lecithin (SL), egg yolk lecithin (EL), or krill oil (KO) supplementation were formulated for Cherax quadricarinatus (72.32 ± 3.58 g). Ovary development and physiological characteristics of crayfish were evaluated after a 10-week feeding trial. The results indicated that SL, EL, or KO supplementation all significantly increased the gonadosomatic index, especially in the KO group. Crayfish fed the diet with SL showed the highest hepatosomatic index compared with those fed the other experimental diets. KO was more efficient than SL and EL in promoting triacylglycerol and cholesterol deposition in the ovary and hepatopancreas but also showed the lowest concentration of low-density lipoprotein cholesterol in the serum. KO significantly increased yolk granule deposition and accelerated oocyte maturation than other experimental groups. Furthermore, dietary phospholipids significantly enhanced the gonad-stimulating hormone concentration in the ovary and reduced the secretion of gonad-inhibiting hormones in the eyestalk. KO supplementation also significantly improved organic antioxidant capacity. From the ovarian lipidomics results, phosphatidylcholine and phosphatidylethanolamine are two main glycerophospholipids that respond to different dietary phospholipids. Polyunsaturated fatty acids (especially C18:2n-6, C18:3n-3, C20:4n-6, C20:5n-3, and C22:6n-3) were pivotal participants during ovarian development of crayfish regardless of lipid type. Combined with the ovarian transcriptome, the best positive function of KO was due to activated steroid hormone biosynthesis, sphingolipid signaling, retinol metabolism, lipolysis, starch and sucrose metabolism, vitamin digestion and absorption, and pancreatic secretion. As a consequence, dietary supplementation with SL, EL, or KO all improved the ovarian development quality of C. quadricarinatus, especially KO, which was the optimum choice for promoting ovary development in adult female C. quadricarinatus. [ABSTRACT FROM AUTHOR]

We conducted a Very Long Baseline Array (VLBA) observation of the low mass active galactic nucleus (AGN) in galaxy NGC 4293 (z  = 0.003). The object is associated with a low-ionization nuclear emission-line region (LINER). Its black hole mass is estimated as ∼105 or |${\sim}10^7 \, \mathrm{M}_\odot$|⁠. The VLBA 1.5 GHz image shows an inverse symmetric structure with two discrete radio blobs separated by an angular distance of ∼120 mas, corresponding to ∼7 parsec. Furthermore, its integrated radio spectrum has a turnover at the frequency of ∼0.44 GHz. Based on the compactness and spectrum, the nuclear radio source in NGC 4293 belongs to a sample of (megahertz) peaked spectrum (PS/MPS) radio sources with compact symmetric morphologies. NGC 4293 has 1.4 GHz radio power of only |${\sim}10^{20}\, \mathrm{W\, Hz^{-1}}$| with the VLBA observation, which is consistent with local AGNs but lower than the current PS samples. One of the two blobs has a steep radio spectrum α = −0.62 ± 0.08 (S ν ∝ ν+α), while the other one has an inverted spectrum α = 0.32 ± 0.10. The VLBA 1.5 GHz luminosity ratio of the two blobs is 3.23 and both blobs show lateral-flowing structures where the hotspots reside at the edge of each radio lobe. This can be explained as jet interactions with dense circumnuclear medium. We estimate the black hole mass of NGC 4293 through the Fundamental Plane of black hole activity, which constrains the black hole mass to be |${\lesssim}10^6\, \mathrm{M}_\odot$|⁠. It supports that the object is a low-mass AGN and a potential candidate for accreting and ejecting IMBHs. [ABSTRACT FROM AUTHOR]

Multiply twinned icosahedrons possess a diversity of unique functionalities well‐suited to various applications, such as thermoelectric conversion. Regarding chalcogenide icosahedron, an unconventional yet promising thermoelectric candidate, disclosing its growth mechanism is rather challenging. This study uncovers the formation mechanism of thermoelectric Cu5+3xFe1‐xS4 (0 ≤ x ≤ 0.4) core‐shell nano‐icosahedrons, which is distinct from that of well‐known metal icosahedrons. Electron microscopy and molecular dynamics simulations reveal that the evolution into icosahedrons, stemming from the fivefold twin formation in the center of Cu5FeS4 particle aggregates, is accompanied by the gradual formation of Fe‐rich orthorhombic‐structured core and Cu‐rich cubic‐structured shell, which provides a peculiar stress relaxation mechanism. Further identified by density functional theory calculations, Fe atoms have the tendency to transform cubic Cu5FeS4 to its orthorhombic phase and in turn result in varied crystal structures and lattice parameters in the core and shell. Importantly, by adjusting the Cu/Fe ratio of the precursors, the stress‐releasing process and potential energy of icosahedrons are controllably tuned, generating Cu5+3xFe1‐xS4 icosahedrons with tunable diameters. Accordingly, a significantly enhanced thermoelectric zT of 0.90, the largest value for Cu5FeS4, is realized. This study will shed light on the design strategy for Cu‐based ternary chalcogenide icosahedrons with enhanced thermoelectric properties. [ABSTRACT FROM AUTHOR]

Gossypol is a polyphenolic toxic secondary metabolite derived from cotton. Free gossypol in cotton meal is remarkably harmful to animals. Furthermore, microbial degradation of gossypol produces metabolites that reduce feed quality. We adopted an enzymatic method to degrade free gossypol safely and effectively. We cloned the gene cce001a encoding carboxylesterase (CarE) into pPICZαA and transformed it into Pichia pastoris GS115. The target protein was successfully obtained, and CarE CCE001a could effectively degrade free gossypol with a degradation rate of 89%. When esterase was added, the exposed toxic groups of gossypol reacted with different amino acids and amines to form bound gossypol, generating substances with (M + H) m/z ratios of 560.15, 600.25, and 713.46. The molecular formula was C27H28O13, C34H36N2O6, and C47H59N3O3. The observed instability of the hydroxyl groups caused the substitution and shedding of the group, forming a substance with m/z of 488.26 and molecular formula C31H36O5. These properties render the CarE CCE001a a valid candidate for the detoxification of cotton meal. Furthermore, the findings help elucidate the degradation process of gossypol in vitro. [ABSTRACT FROM AUTHOR]

Microbial degradation techniques are often considered an environmentally friendly and cost-effective strategy for reducing gossypol toxicity. However, the mechanism by which Candida tropicalis degrades gossypol remains unclear. In the current study, we aimed to establish the mechanisms of biodegradation and adaptation mechanisms by C. tropicalis ZD-3. The toxicological evaluation results revealed that ZD-3 adapts to gossypol primarily by activating the antioxidant defense system to alleviate the oxidative stress response induced by gossypol. Transcriptomic analyses further suggested that ZD-3 protects against gossypol toxicity via cell wall remodeling. The intracellular enzyme CTRG_04744 gene was significantly up-regulated under gossypol stress, and then expressed in Pichia pastoris. The purified AKR_Z1 degraded 92 % of gossypol within 48 h. In addition, the aldehyde group of gossypol was effectively eliminated to achieve the desired detoxification. Collectively, these results provide theoretical guidance for the continued development of bio-efficient strategies capable of degrading gossypol. [Display omitted] [ABSTRACT FROM AUTHOR]

• The strategy based on the combination of equivalent medium theory and A-star algorithm implemented the customization of the selective emitters. • A-star algorithm was adopted for efficient and enlightening optimization of 2 or 3 parameters. • Based on the critical coupling theory, the mechanism of parameters and material changes on the performance of MDM structures were expounded. Metal-dielectric-metal (MDM) structure can selectively emit infrared wave because of the local plasma resonance; it has attracted intensive attentions in sensor, radiative cooling and many other fields. However, it remains challenging to efficiently design a customized near-ideal selective emitter. In this work, a concise design method that combined equivalent medium theory with A-star algorithm was developed for the reversed design of the MDM structure. This strategy for designing and optimizing the MDM structure, implemented the customization of the selective emitters. Meanwhile, design efficiency was improved by ∼10 times. A variety of near-ideal selective infrared emitters at 6 μm were designed based on different materials. The essence of structural parameter or material change was to adjust the radiation damping and dissipative damping of the structure to regulate the spectral radiation characteristics, such as emissivity peak and full width at half maximum (FWHM). The Q-factor of the high-performance selective emitter depends on the higher loss tangent of metals. Both the computational method and the concluded results of this work would provide enlightenment for future design of MDM structures intended for many cutting-edge applications, such as infrared sensing and radiative cooling. [ABSTRACT FROM AUTHOR]

As wind turbine blades increase in size and flexibility, the structural deformation becomes more pronounced and significantly influences the aerodynamic performance of the wind turbine. This paper introduces a fluid-structure interaction (FSI) analysis model that employs the actuator line technique and equivalent beam theory to assess the aeroelastic behaviour of wind turbines under various inflow scenarios. After validating the FSI model, it is used to simulate the aeroelastic responses of the NREL 5 MW wind turbine under various inflow conditions. The aerodynamic loads, structural dynamic responses, and wake field characteristics are thoroughly analysed, detailing the effects of various inflow conditions, such as wind speed and inflow type, on the aeroelasticity of the wind turbine. The findings reveal that blade deformation reduces average aerodynamic loads under various inflow conditions, with the effect intensifying at higher wind speeds. Blade deformation's impact is more profound on aerodynamic thrust than on aerodynamic power, and it significantly influences the variation amplitude of aerodynamic loads rather than their average values. Additionally, with increasing wind speed, blade deformation notably increases wake velocity and reduces wake field turbulence intensity. Under turbulent inflow, however, the rise in wake velocity due to blade deformation diminishes, while turbulence intensity increases, comparing with uniform and shear inflow conditions. • An elastic actuator line model is developed to assess the aeroelastic behaviour of wind turbines. • Effects of wind speed and inflow type on the aeroelasticity of the wind turbine are thoroughly examined. • As wind speed increases, blade deformation enhances wake velocity and diminishes turbulence intensity in the wake field. [ABSTRACT FROM AUTHOR]

Phonon energies at finite temperatures shift away from their harmonic values due to anharmonicity. In this paper, we have realized the rigorous calculation of phonon energy shifts of silicon by three- and four-phonon scattering from first principles. The anharmonic fourth-order force constants are calculated by considering up to the fifth nearest neighbors. The results agree reasonably well with available data from inelastic neutron scattering throughout the Brillouin zone. Surprisingly, the frequency shifts of optical phonon modes near the Γ point are sensitive to the cutoff radius of the fourth-order force constants, in contrast to the four-phonon scattering rates, which nearly saturate when considering the second nearest neighbors. We have also compared the results with ab initio molecular dynamics simulations and found that the higher order of anharmonicity is important for optical phonons. Our work provides critical insight into the anharmonic phonon frequency shift and will have a significant impact on the thermal and optical applications. [ABSTRACT FROM AUTHOR]

The electron–phonon coupling (EPC) in semiconductors is typically much weaker than phonon–phonon scattering and its effect on lattice thermal conductivity κl has long been considered negligible. Herein, using first‐principle calculations, it is discovered that the EPC can be significant or even dominant over the intrinsic phonon–phonon scattering via doping in 2D semiconductor hexagonal boron phosphorus (h‐BP). Filling electron pocket till van Hove singularity gradually strengthens the EPC and consequently diminishes the room‐temperature κl by 25% and 80% for monolayer and bilayer h‐BP, respectively. Strikingly, at high doping levels, the EPC drives phonon transport in bilayer h‐BP to an anomalous regime where κl becomes nearly temperature (T) independent deviated from the intrinsic 1/T trend. This distinctive behavior is governed by the joint effects of horizontal mirror symmetry breaking, and weak phonon–phonon scattering stemming from the predominance of normal processes. Further considering electronic contributions, the abnormal T‐independent thermal conductivity is still reserved, thereby facilitating the experimental exploration of EPC effect on κl. This study unveils the exotic thermal transport phenomenon in one‐atom‐thick 2D semiconductors and offers a unique avenue to manipulate heat flow by externally controlling the EPC, which calls for future experimental verification. [ABSTRACT FROM AUTHOR]

NGC 4395 is a dwarf galaxy at a distance of about 4.3 Mpc (scale: ∼0.021 pc mas−1). It hosts an intermediate-mass black hole (IMBH) with a mass between ∼104 and ∼105 solar masses. The early radio observations of NGC 4395 with the very long baseline interferometry (VLBI) network, High Sensitivity Array (HSA), at 1.4 GHz in 2005 showed that its nucleus has a sub-mJy outflow-like feature (E) extending over 15 mas. To probe the possibility of the feature E as a continuous jet with a base physically coupled with the accretion disc, we performed deep VLBI observations with the European VLBI Network (EVN) at 5 GHz, and analysed the archival data obtained with the HSA at 1.4 GHz in 2008, NSF's Karl G. Jansky Very Large Array (VLA) at 12–18 GHz and the Atacama Large Millimetre/submillimetre Array (ALMA) at 237 GHz. The feature E displays more diffuse structure in the HSA image of 2008 and has no compact substructure detected in the EVN image. Together with the optically thin steep spectrum and the extremely large angular offset (about 220 mas) from the accurate optical Gaia position, we explain the feature E as nuclear shocks likely formed by the IMBH's episodic ejection or wide-angle outflow. The VLA and ALMA observations find a sub-mJy pc-scale diffuse feature, possibly tracing a thermal free–free emission region near the IMBH. There is no detection of a jet base at the IMBH position in the VLBI maps. The non-detections give an extremely low luminosity of ≤4.7 × 1033 erg s−1 at 5 GHz and indicate no evidence of a disc-jet coupling on sub-pc scales. [ABSTRACT FROM AUTHOR]

In this paper, we study the nonlinear Choquard equation { − Δ u + λ u = (I 2 ∗ | u | p) | u | p − 2 u in Ω , u ∈ H 0 1 (Ω) , where Ω ⊂ R N is an unbounded domain, ∂ Ω ≠ ∅ is bounded, λ ∈ R + , p = 2 if N = 3, 4, 5 or 2 < p < 7 3 if N = 3. By global compactness analysis, we show that the problem has at least one positive high energy solution. [ABSTRACT FROM AUTHOR]

SUMMARY: Alternating current preheating can effectively heat the cell while preventing lithium deposition. However, its application in real situation is limited by availability of negative electrode impedance and generation of sinusoidal alternating current (SAC). Based on the fact that negative electrode impedance is dominant in full cell impedance at low temperatures, the strategy of replacing the negative electrode impedance with the full cell impedance is proposed. Generating SAC on vehicle is costly, and may not be the most efficient waveshape in preheating the cell. The strategy of substituting SAC using square wave alternating current (SWAC) is further proposed. Based on the former strategy, applicability boundaries of preventing lithium deposition in terms of frequency and maximum permissible current amplitude for SWAC are provided. Its effectiveness is checked using an 18 650 cell. Neither apparent lithium deposition nor life degradation is exhibited after repeated preheating of 600 min. The preheating rate with different current waveshapes are experimentally compared. The SWAC has larger preheating capability and can warm up the cell in shorter time. To further improve the preheating rate, a temperature‐adaptive profile is developed according to the applicability boundaries, successfully preheating an 18 650 cell from −20°C to 6°C in 540 s. [ABSTRACT FROM AUTHOR]

X-shaped radio galaxies (XRGs) are those that exhibit two pairs of unaligned radio lobes (main radio lobes and wings). One of the promising models for the peculiar morphology is jet reorientation. To clarify this, we conducted a 5 GHz observation with the European VLBI Network (EVN) of XRG J0725+5835, which resembles the archetypal binary active galactic nuclei (AGNs) 0402+379 in radio morphology, but it is larger in angular size. In our observation, two milliarcsecond-scale radio components with nonthermal radio emission are detected. Each of them coincides with an optical counterpart with similar photometric redshift and (optical and infrared) magnitude, corresponding to dual active nuclei. Furthermore, with the improved Very Large Array (VLA) images, we find a bridge between the two radio cores and a jet bending in the region surrounding the companion galaxy. This further supports the interplay between the main and companion galaxies. In addition, we also report the discovery of an arcsecond-scale jet in the companion. Given the projected separation of ∼100 kpc between the main and companion galaxies, XRG J0725+5835 is likely associated with a dual jetted-AGN system. In both EVN and VLA observations, we find signatures that the jet is changing its direction, which is likely responsible for the X-shaped morphology. For the origin of jet reorientation, several scenarios are discussed. [ABSTRACT FROM AUTHOR]

In this paper, we consider the existence of normalized solutions to the following system: −Δu + V1(x)u + λu = μ1u3 + βv2u and −Δv + V2(x)v + λv = μ2v3 + βu2v in R 3 , under the mass constraint ∫ R 3 u 2 + v 2 = ρ 2 , where ρ is prescribed, μi, β > 0 (i = 1, 2), and λ ∈ R appears as a Lagrange multiplier. Then, by a min–max argument, we show the existence of fully nontrivial normalized solutions under various conditions on the potential V i : R 3 → R (i = 1 , 2). [ABSTRACT FROM AUTHOR]

Caching popular contents at edge networks (such as small-cell base stations) has been proposed to deal with the ever-growing mobile traffic. At the meantime, recommendation system is able to shape user demands for further prompting caching gain. In this paper, we study a multi-antenna multi-cell edge network employing transmit beamforming with caching-aware recommendation and user association. We first establish a framework for the joint problem of beamforming, user association, content caching and recommendation to minimize the content transmission delay of mobile users, by specifying a set of necessary conditions for all four component functions of the network. The resulting optimization problem corresponds to a non-convex, multi-timescale, and mixed-integer programming problem, which is hard to handle. To deal with the difficulty in solving the joint optimization problem by the direct formulation, we equivalently decompose it into three sub-problems. Then, we develop a computationally-efficient iterative algorithm to obtain the sub-optimal solution, where the three subproblems are tackled iteratively. Simulation results are conducted to demonstrate that the proposed algorithm can obtain lower transmission delay than baseline schemes. [ABSTRACT FROM AUTHOR]

Summary: The performance of the lithium‐ion battery decreases significantly at low temperature and it generally requires preheating before usage. Based on the constant‐voltage‐discharge(CVD) preheating method, a series of experimental studies on the preheating efficiency (PE) and energy consumption ratio (ECR) of an aluminum‐rich high discharge rate ternary lithium‐ion battery at low temperature were carried out. The influences of discharge voltage, state of charge (SOC), ambient temperature on the PE, and ECR were investigated in details. The effect of CVD on battery aging was also investigated. The experimental results showed that CVD preheating had a good preheating performance. Under the same experimental conditions, the PE increases with the decrease of discharge voltage and the increase of ambient temperature, but decreases with the decrease of SOC. The ECR decreases with the discharge voltage decreasing and ambient temperature increasing, but increases with the SOC decreasing. The results also showed that energy for external work (Q1) and energy released to the external environment (Q3) takes up a large proportion of total energy under different preheating parameters during the preheating process, which is a possible way to improve the CVD efficiency. At last, the battery aging is found to increase with the preheating voltage decreasing. After 300 preheating cycles, the maximum reduction of battery capacity is about 5.64% for the 2.3 V CVD case. [ABSTRACT FROM AUTHOR]

Formic acid decomposition (FAD) is one of the most promising routes for rapid hydrogen (H2) production. Extensive efforts have been taken to develop efficient catalysts, which calls for the simultaneous regulation of the electronic structure and particle size of the catalyst. The former factor determines the intrinsic performance, while the latter corresponds to the active site utilization. Here, an effective preparation strategy, pre-nucleation coupled with in situ reduction, is developed to realize and well-tune both surface electronic states and particle size of the pallidum (Pd) catalyst. Benefiting from the structural merits, the as-prepared catalyst exhibits high mass-specific activity of 8.94 molH2/(gPd·h) with few carbon monoxide (CO) molecules, and the activation energy could reach a value as small as 33.1 kJ/mol. The work not only affords a highly competitive FAD catalyst but also paves a new avenue to the synthesis of ultra-fine metal nanoparticles with tailorable electronic structures. [ABSTRACT FROM AUTHOR]

The general design equations are derived for arbitrary odd-way Bagley polygon power divider (BPPD) with filtering response and notch band. Firstly, conditions are derived to achieve a perfect input port impedance matching at centre frequency. Then, the formulas of introduced transmission zeros (TZs) are obtained for high-frequency selectivity, wide upper stopband and notch band. Based on the deduced equations, wideband BPPD (WBPPD), filtering BPPD (FBPPD) and FBPPD integrating notch band (FBPPD-N) with arbitrary odd-way power splitting are designed. Finally, a FBPPD-N with a wide passband bandwidth is fabricated and measured to verify the presented ideal. The experimental results indicate that the proposed FBPPD-N has compact size, high-frequency selectivity, wide upper stopband and required notch band. Consequently, the presented general design equations can provide effective guidance for the design of arbitrary odd-way power splitting FBPPD-N. [ABSTRACT FROM AUTHOR]

In order to solve the leakage problem of rotating machinery under the condition of large clearance, a new type of divergent magnetic fluid sealing device with secondary magnetic source was designed. The magnetic field distribution in the clearance of the magnetic fluid seal was simulated by the finite element method of magnetic field, and the theoretical value of the sealing pressure resistance was calculated according to the pressure resistance theory of the divergent magnetic fluid seal. The influences of the volume of magnetic fluid injection, the number of teeth, the clearance, and the eccentricity of the rotating shaft on the pressure resistance abilities of divergent magnetic fluid seal were studied by experimental method and compared with the pressure resistance experimental value of ordinary magnetic fluid seal. The results showed that when the injection volume of magnetic fluid is more than 3 ml, the sealing pressure resistance ability of the magnetic fluid does increase greatly and tends to be stable gradually. The saturated magnetic fluid injection volume of divergent magnetic fluid seal with large clearance is 3 ml. With the increase of radial teeth, the pressure resistance ability of magnetic fluid seal first increases and then decreases. With the increase of axial teeth, the pressure resistance ability of magnetic fluid seal also increases. With the increase of radial clearance, the pressure resistance value of magnetic fluid seal first increases and then decreases. With the increase of axial clearance, the pressure resistance value of magnetic fluid seal decreases. The pressure resistance ability of divergent magnetic fluid seal is significantly higher than that of ordinary magnetic fluid seal. [ABSTRACT FROM AUTHOR]

Proton‐exchange membrane fuel cells (PEMFCs) are limited by their extreme sensitivity to trace‐level CO impurities, thus setting a strict requirement for H2 purity and excluding the possibility to directly use cheap crude hydrogen as fuel. Herein, we report a proof‐of‐concept study, in which a novel catalyst comprising both Ir particles and Ir single‐atom sites (IrNP@IrSA‐N‐C) addresses the CO poisoning issue. The Ir single‐atom sites are found not only to be good CO oxidizing sites, but also excel in scavenging the CO molecules adsorbed on Ir particles in close proximity, thereby enabling the Ir particles to reserve partial active sites towards H2 oxidation. The interplay between Ir nanoparticles and Ir single‐atom centers confers the catalyst with both excellent H2 oxidation activity (1.19 W cm−2) and excellent CO electro‐oxidation activity (85 mW cm−2) in PEMFCs; the catalyst also tolerates CO in H2/CO mixture gas at a level that is two times better than that of the current best PtRu/C catalyst. [ABSTRACT FROM AUTHOR]

Proton‐exchange membrane fuel cells (PEMFCs) are limited by their extreme sensitivity to trace‐level CO impurities, thus setting a strict requirement for H2 purity and excluding the possibility to directly use cheap crude hydrogen as fuel. Herein, we report a proof‐of‐concept study, in which a novel catalyst comprising both Ir particles and Ir single‐atom sites (IrNP@IrSA‐N‐C) addresses the CO poisoning issue. The Ir single‐atom sites are found not only to be good CO oxidizing sites, but also excel in scavenging the CO molecules adsorbed on Ir particles in close proximity, thereby enabling the Ir particles to reserve partial active sites towards H2 oxidation. The interplay between Ir nanoparticles and Ir single‐atom centers confers the catalyst with both excellent H2 oxidation activity (1.19 W cm−2) and excellent CO electro‐oxidation activity (85 mW cm−2) in PEMFCs; the catalyst also tolerates CO in H2/CO mixture gas at a level that is two times better than that of the current best PtRu/C catalyst. [ABSTRACT FROM AUTHOR]

Proton‐exchange membrane fuel cells (PEMFCs) are limited by their extreme sensitivity to trace‐level CO impurities, thus setting a strict requirement for H2 purity and excluding the possibility to directly use cheap crude hydrogen as fuel. Herein, we report a proof‐of‐concept study, in which a novel catalyst comprising both Ir particles and Ir single‐atom sites (IrNP@IrSA‐N‐C) addresses the CO poisoning issue. The Ir single‐atom sites are found not only to be good CO oxidizing sites, but also excel in scavenging the CO molecules adsorbed on Ir particles in close proximity, thereby enabling the Ir particles to reserve partial active sites towards H2 oxidation. The interplay between Ir nanoparticles and Ir single‐atom centers confers the catalyst with both excellent H2 oxidation activity (1.19 W cm−2) and excellent CO electro‐oxidation activity (85 mW cm−2) in PEMFCs; the catalyst also tolerates CO in H2/CO mixture gas at a level that is two times better than that of the current best PtRu/C catalyst. [ABSTRACT FROM AUTHOR]

In order to solve the problem of reciprocating seal for hydraulic cylinder, a new structure of Magnetorheological fluid (MRF) reciprocating seal with increasing width of pole teeth and pole piece was designed. The theoretical analysis of MRF reciprocating seal is carried out. The magnetic field intensity distribution in the sealing gap of MRF reciprocating seal was analyzed by finite element method. According to the pressure capability formula of MRF, the theoretical pressure capability is calculated. The influences of structure parameters such as the number of magnetic sources, sealing gap height, pole teeth length, the ratio of permanent magnet height to its length, the ratio of pole piece height to shaft radius on the sealing capabilities were studied. The results showed that the pressure capability of MRF reciprocating seal increases with the increase of the number of magnetic sources and with the decrease of the sealing gap height. With the increase of the pole tooth length, the pressure capability of the reciprocating seal increases. With the increase of the ratio of permanent magnet height to its length, the pressure capability of the reciprocating seal increases first and then decreases. With the increase of the ratio of the pole piece height to shaft radius, the pressure capability of the MRF reciprocating seal increases first and then decreases. [ABSTRACT FROM AUTHOR]