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Soluble aluminum alloy materials used in underground operational tools are synthesized via a high-temperature smelting process. The microstructure and composition distribution of the alloy were analyzed using X-ray diffraction, metallographic microscopy, and scanning electron microscopy with energy-dispersive X-ray and electron backscatter diffraction techniques. The mechanical properties were evaluated using a universal testing machine and hardness tester, while solubility assessments were conducted in a constant-temperature water bath. This study focuses on the plasticity and dissolution characteristics of Al-Mg-Ga-Sn-In alloys with varying Mg contents. The tensile strength (σb) of the alloy was 181.99 MPa, with an elongation (δ) of 27.49% and cross-sectional shrinkage (φ) of 11.67% at a magnesium content of 3.0 wt.%. Additionally, in the compressive test, the compressive yield strength (σsc) was recorded at 188.32 MPa, while the compression rate (δ) was 27.06% and the section expansion rate (φ) was 138.66%. Furthermore, the alloy demonstrated the ability to dissolve spontaneously in water at 90 °C, exhibiting an average dissolution rate of 1.0 g·h−1cm−2 and a maximum dissolution rate of 3.25 g·h−1cm−2 after 12.0 h. Consequently, this alloy composition not only satisfies the requirements for rapid solubility but also exhibits favorable plasticity, providing a novel reference for the selection of soluble aluminum alloy materials. [ABSTRACT FROM AUTHOR]

Retinal disorders are a major cause of irreversible vision loss, which can be mitigated through accurate and early diagnosis. Conventionally, fundus images are used as the gold diagnosis standard in detecting retinal diseases. In recent years, more and more researchers have employed deep learning methods for diagnosing ophthalmic diseases using fundus photography datasets. Among the studies, most of them focus on diagnosing a single disease in fundus images, making it still challenging for the diagnosis of multiple diseases. In this paper, we propose a framework that combines ResNet and Transformer for multi-label classification of retinal disease. This model employs ResNet to extract image features, utilizes Transformer to capture global information, and enhances the relationships between categories through learnable label embedding. On the publicly available Ocular Disease Intelligent Recognition (ODIR-5 k) dataset, the proposed method achieves a mean average precision of 92.86%, an area under the curve (AUC) of 97.27%, and a recall of 90.62%, which outperforms other state-of-the-art approaches for the multi-label classification. The proposed method represents a significant advancement in the field of retinal disease diagnosis, offering a more accurate, efficient, and comprehensive model for the detection of multiple retinal conditions. [ABSTRACT FROM AUTHOR]

Soil electrical conductivity has been extensively investigated in the fields of precision agriculture, geophysical mapping, and soil property mapping. However, the understanding of soil electro-osmotic conductivity is currently limited. Comprehensive insight into soil electro-osmotic conductivity is crucial for an accurately designing the electro-osmosis technique, which is widely accepted as a highly promising method for disposing soft soils with high water content. To fill this knowledge gap, a series of laboratory experiments was conducted using Hangzhou sludge. Four factors, including electrode material, potential gradient, soil water content, and pore water salinity, were investigated in terms of their influence on electrical conductivity of the electro-osmotically treated soil. Results show that during the electro-osmosis process, the soil electro-osmotic conductivity initially slightly increases and then decreases. The impact of electrode materials on soil electro-osmotic conductivity was minimal, whereas a high potential gradient was observed to generate low soil electro-osmotic conductivity. Furthermore, this conductivity was found to be linearly correlated with real-time water content. The slope of the correlation was also significantly influenced by the initial water content of the soil. Under different levels of pore water salinity, the soil electro-osmotic conductivity first increases to a peak and then decreases to a residual value. The soil electro-osmotic conductivity are observed to have a linear relationship with pore water salinity. These implications are closely linked to the soil conduction mechanism. Based on the foregoing findings, limiting the calculations to the pore water-induced conduction during the main stages of the electro-osmosis process is recommended. Furthermore, linear predictive relationships between soil electro-osmotic conductivity and the corresponding level of soil water content as well as between the soil electro-osmotic conductivity and the pore water salinity should be used in simplified calculation of the electro-osmosis process. The parameters involved in these relationships can be accurately determined through laboratory experiments. [ABSTRACT FROM AUTHOR]

The development of the textile and apparel (T&A) industry has led to an increasing focus on recycling used products. Remanufactured product quality raises consumer concerns, and blockchain can effectively solve this problem. We establish a closed-loop supply chain (CLSC) in which a manufacturer, a retailer, or a third-party recycler collects used T&A products to examine the most efficient recycling mode with and without blockchain and the impact of blockchain on CLSC decisions. The results show that (1) if the manufacturer's recycling cost coefficient is relatively low, used T&A products are collected directly by the manufacturer. Otherwise, the responsibility for recycling used T&A products falls to the retailer or the third-party recycler. It is noteworthy that the manufacturer's choice of recycling mode remains unchanged whether a blockchain is implemented or not. (2) The implementation of blockchain by the manufacturer and the retailer can increase profits and consumers also benefit when the cost of validating blockchain units remains below a certain threshold. (3) When the recycling cost coefficient exceeds a certain threshold, the implementation of blockchain increases prices and recycling rates. These findings offer CLSC members' management insights into how to select the optimal recycling mode and the consequences of implementing blockchain. [ABSTRACT FROM AUTHOR]

Taking advantage of multimaterial additive manufacturing, this work demonstrates a kind of polarization‐maintaining metasurface (MS) for spin‐decoupled beam shaping. The wavefronts of the two spin states, i.e., the left‐hand circular polarization (LHCP) and the right‐hand circular polarization (RHCP), can be independently manipulated while the output spin state remains the same as the input. The meta‐atom is implemented with dual‐polarized antennas at the top and the bottom with phase delay lines connecting them. The dual‐polarized antenna on the receiving side is fixed to receive the LHCP/RHCP incident waves, while the dual‐polarized transmitting antenna is rotated, providing the opposite phase shifts for the LHCP and RHCP. The absolute value of the phase shift is the same as the transmitting antenna's rotation angle. Meanwhile, varying the length of phase delay lines introduces 2π phase shifts for both LHCP and RHCP inputs. Thus, combining the two phase‐shifting degrees of freedom, the LHCP and RHCP wavefronts can be independently controlled while the polarization is not flipped after transmitting through the MS. One MS produces vortex beams with different topological charges for LHCP and RHCP. The other achieves spin‐decoupled focusing. The multilayered MSs are conveniently printed using multimaterial additive manufacturing without postprocessing. [ABSTRACT FROM AUTHOR]

Two-dimensional numerical simulations are performed to investigate the interactions between a rotating detonation combustor (RDC) and turbine. The flowfield structure and coupling characteristics are analyzed under different equivalent ratios. Furthermore, the formation mechanism of the detonation wave direction is illustrated. Results show that although RDCs increase the average turbine work, they enhance the flowfield oscillation and maintain the quasi-periodic fluctuation in the turbine work. Compared to counter-clockwise propagation, the pressure oscillation attenuation and total pressure loss through the turbine guide vane increase when the detonation wave propagates clockwise. When the detonation wave height is low, RDCs are more prone to quenching due to the impact of reflected waves. After re-ignition, the detonation wave direction is unrelated to the initial ignition direction and is random. Introduction of deflecting wedges into RDCs enables the automatic control of the detonation wave direction but causes extra total pressure loss of at least 3.6%. • Two-dimensional simulations of rotating detonation combustor with one-stage turbine. • Coupling characteristics between rotating detonation combustor and turbine. • Formation mechanism of the detonation wave direction under turbine influence. • Automatic control of detonation wave direction by introducing deflecting wedges. [ABSTRACT FROM AUTHOR]

This article proposes 3D printed broadband transmissive metasurfaces for spin‐decoupled wavefront shaping based on a versatile broadband cross‐polarization rotation meta‐atom. A meta‐atom combining broadband cross‐linear polarization dynamic phase and Pancharatnam–Berry (P–B) phase is demonstrated to realize spin‐decoupled beam shaping. The meta‐atom is built in an antenna‐circuit‐antenna fashion. Stacked patch antennas are used here as both the receiving and transmitting antennas because they can achieve wide bandwidth and good impedance matching to free space. By carefully selecting the phase delay lines' path, the meta‐atom converts the x‐polarized or y‐polarized linear incident wave to its cross‐polarization with the co‐polarized components suppressed. The function also leads to the spin conversion for the circularly polarized incident wave. Thus, P–B phase‐shifting will be introduced when the meta‐atom is rotated. In addition, the transmission line provides the same dynamic phase delay for both left‐ and right‐hand circular polarization (LHCP and RHCP) incident waves. Then, combining the two different phase‐shifting methods, i.e., the P–B phase and dynamic phase, the LHCP and RHCP wavefront can be fully decoupled. Two different metasurfaces achieving spin‐decoupled anomalous refraction carrying orbital angular momentum (OAM) with different topological charges are simulated and experimentally verified for demonstration. [ABSTRACT FROM AUTHOR]

This study aimed to develop a soluble aluminum alloy material for isolation tools, characterized by high hardness, high tensile strength, and low dissolution rate. To achieve this, the Al-Zn-Mg-Ga-In-Sn soluble aluminum alloy was cast at high temperatures using a medium frequency metal induction melting furnace. The effects of different aging heat treatment processes on the mechanical properties and dissolution performance of the Al-Zn-Mg-Ga-In-Sn soluble aluminum alloy, which had undergone a solution heat treatment at 470℃ for 12 hours followed by air cooling to 25℃, were investigated. The results indicated that after aging heat treatment at 175℃ for 2 hours followed by air cooling to 25℃, the alloy exhibited uniform grain size, averaging 35±2μm. The precipitated phase Mg 2 Sn had an average size of 7.6±1.0 μm, with fewer in number, primarily located at the grain boundaries. Furthermore, the alloy demonstrated excellent mechanical properties, including a tensile strength of 334±1 MPa, yield strength of 226±1 MPa, and elongation of 16.6±0.5 %. Additionally, its hardness reached 91±3 HB. The dissolution rate in 90℃ distilled water was 1.6±1.0 g·h−1·cm−2, with the alloy surface showing relatively uniform dissolution characteristics during the process, and a dissolution depth of 741±5 μm. • Al-Zn-Mg-Ga-In-Sn soluble aluminum alloy can be completely dissolved in aqueous solutions. • The alloy undergoes dual heat treatment of solid solution and aging. • The alloy has a high hardness of 91± 3HB. • Using this soluble material to prepare sealing tools can significantly improve the mining rate. • This composite heat treatment process provides a new direction for the modification of soluble aluminum alloy materials. [ABSTRACT FROM AUTHOR]

The ceramic composites were designed through the regulation of the composition and temperature in the in-situ oxidized SiC/Al–Mg–Si composites process. The evolutions of the phase and microstructure were studied by X-ray Diffraction(XRD), Scanning Electron Microscope (SEM), and Transmission Electron Microscope(TEM) in different alloy addition and heating temperature. The products of in-situ oxidized SiC/Al–Mg–Si composites showed similar compositions due to high oxidation resistance on SiC since the heated temperature was below 1500 °C. Alloy addition dislodges the oxide shell on SiC. It promoted the oxidation of SiC, providing the sustained-release Si source to form the cordierite, mullite, and forsterite. Moissanite/spinel, mullite/spinel, and cordierite/spinel were obtained by controlling temperature or adding alloy. The mullite rods formed in 20% alloy addition samples at 1350 °C was detected. The step-like microstructure revealed that grains abide by a layer growth mechanism. The bending strength was enhanced from 13.83 ± 3.6 MPa to 22.32 ± 4.3 MPa by eutectic melting, which increased with the alloy addition and elevated temperature. [ABSTRACT FROM AUTHOR]

Arbitrarily manipulating the polarization and wavefront of electromagnetic waves using ultrathin and highly efficient devices is desirable for many systems. Ultrathin broadband polarization‐insensitive transmissive metasurfaces, which can achieve the same polarization conversion and wavefront shaping for arbitrary linearly polarized incident waves, are proposed. The meta‐atom is composed of a transmitting antenna and a receiving antenna with a group of phase delay lines connecting them. The rotation of the transmitting antenna introduces the polarization conversion, and the different lengths of the transmission lines provide [−π, π] phase shift for wavefront shaping. Both the polarization conversion and wavefront shaping functions are polarization insensitive. Differential feeding is applied to both the transmitting and the receiving patch antennas to improve the transmission efficiency. The prototypes are conveniently printed by using the additive manufacturing technique. Two polarization‐insensitive metasurfaces are designed and measured to demonstrate. One of them produces vortex beams with 90° polarization conversion, and the other achieves anomalous refraction with 45° polarization conversion. [ABSTRACT FROM AUTHOR]

This article presents 3-D printed metal-only dual-band millimeter-wave circularly polarized (CP) reflectarrays (RAs). The RAs’ unit cell (UC) is made of an anisotropic metal brick mounted on a full metal ground. In-plane rotating the metal brick introduces geometric Pancharatnam–Berry (PB) phase shifting, and vertically adjusting the position of the UC provides propagation phase shifting. The geometric PB and propagation phase shifting offer two different degrees of freedom, enabling independent wavefront shaping of CP wave over dual-band. Specifically, the low-band CP beam shaping solely depends on the propagation phase. In contrast, the high-band CP beam shaping depends on the geometric PB and the propagation phases. The coupling issue between dual-band is minimal because of the unique dual-band phase-shifting methods. In addition, 3-D printed dual-band left-hand CP (LHCP) horn antennas are designed, printed, and used as the feed. To demonstrate, two RA antennas with different dual-band CP beam directions are fabricated and measured. [ABSTRACT FROM AUTHOR]

This communication proposes an additively manufactured metal-only millimeter-wave dual circularly polarized (CP) reflectarray with independent control of polarizations. A metal-only right-hand CP (RHCP) antenna is designed and used as the reflectarray’s phase-shifting unit cell (UC). The RHCP UC is immune to the LHCP incidence, and the UC directly reflects the LHCP incidence into free space. Thus, the phase shifting of the LHCP wave solely depends on the rotation angle of the UC. For the RHCP incidence, it is received by the RHCP UC first and induced into the metal waveguide. Then, the energy is reflected by the ground of the metal waveguide and reradiated into free space with RHCP. Thus, the phase shifting of the RHCP wave is determined by the rotation angle of the UC and the length of the metal waveguide. By properly selecting the rotation angle of the UC and the length of the metal waveguide, RHCP and LHCP can be independently manipulated. To demonstrate, two reflectarray antennas with different LHCP and RHCP beam directions are fabricated using additive manufacturing and experimentally verified. [ABSTRACT FROM AUTHOR]

Coarse-grained reconfigurable architecture (CGRA) is a promising programmable hardware with high power-efficiency and high performance. However, compiling and optimizing loops with irregular branches on CGRAs is a challenge to fulfill the performance potential. Existing predication techniques, such as partial predication (PP) and full predication (FP), conservatively implement software pipeline with a static initiation interval (II) obtained from the maximum graph, and thus only parts of the graph in each loop iteration will be actually executed, resulting in underexploited performance. To exploit more loop-level parallelism for irregular branches, this article proposes a novel dynamic-II pipeline (DIP) scheme, which realizes a pipeline with variable II by accommodating multiple iterations of short path in one static configuration. Since the DIP scheme is effective to only certain types of branches, this article designs a hybrid compilation framework integrating other complementary methods, which selects the appropriate method for source programs according to a proposed performance evaluation model. Experimental results show that: 1) the hybrid compilation framework can effectively extract branch features, correctly choose and implement corresponding branch processing methods within acceptable compile time and 2) as compared to PP and FP, DIP brings a significant total execution time (TET) reduction by 27.21% and 22.04% on average when the execution probability of a short branch is 50%. [ABSTRACT FROM AUTHOR]

Chinese mollusk mariculture plays a key role in boosting ocean carbon sink capacity through biological processes, supported by large-scale production. However, its full potential remains underutilized due to the absence of comprehensive efficiency evaluations. This interdisciplinary study applies a three-stage approach to assess the carbon sink efficiency of Chinese mollusk mariculture, with a focus on regional variations across nine coastal provinces from 2012 to 2022. The results show that environmental variables and statistical noise distort efficiency scores, leading to overestimation in six provinces and underestimation in three. After adjusting for these influences, regional disparities in efficiency become more apparent. High-production provinces such as Shandong, Fujian, and Guangdong exhibit higher efficiency, while low-production provinces like Hainan show diminished performance. Although there is a positive correlation between production volume and carbon sink efficiency, further improvements are constrained by the sector's low profitability. To address this, we propose two strategies: (1) reallocating subsidies from capture fisheries to mollusk mariculture, and (2) accelerating carbon trading between mollusk mariculture and other industries. These measures could enable the global mollusk mariculture to enhance both its carbon sink capacity and efficiency, contributing to food security and climate change mitigation. • A three-stage approach integrating DEA and DEA-Malmquist paradigms for quantitative evaluations. • Comparison on regional variations and evolutionary trends before and after eliminating the interference of external factors. • Strong positive correlation between carbon sink efficiency and mollusk mariculture production. • Fundamental constrains to efficiency enhancement and solutions for achieving both ecological and economic benefits. [ABSTRACT FROM AUTHOR]

To engineer a dissolvable Al-Mg-Ga-Sn aluminum alloy material suitable for multi-stage hydraulic fracturing and sealing tools, an array of alloys was fabricated using high-temperature casting with varying concentrations of Ga and Sn. The compositions were designed such that the ratio of Ga to Sn remained constant at 1. The objective was to examine the influence of Ga and Sn content on the mechanical properties of the alloys and their reactivity with water. Results indicated that with 1.0 wt% of both Ga and Sn, the alloy displayed a ultimate tensile strength (σ b) of 182±1 MPa, elongation (δ) of 33.8±0.8 %, reduction of area (φ) of 11.6±0.9 %, yield strength (σ Sc) of 161±1 MPa, relative compressibility (δ) of 63.0±1.0 %, and relative expansion of the cross-section (φ) of 170.8±0.9 %. Additionally, when subjected to water at 90℃, the alloy achieved a maximum dissolution rate of 3.0±1 g·h-1·cm-2. Upon contact with an aqueous environment, an electrochemical reaction ensues where aluminum atoms in the matrix lose electrons, transforming into Al3+ ions within the solution. Concurrently, Sn2+ and Ga2+ ions migrate to the surface oxide film, substituting Al3+ ions at the grain boundaries, which induces vacancies in the oxide film, reducing its resistance to further ionic penetration and densification loss. This study elucidates the macroscopic process mechanism of the interaction between water-soluble alloys and aqueous media, and proposes a corresponding microscopic mechanism. • Al-Mg-Ga-Sn soluble aluminium alloy can be completely dissolved in water and aqueous solution. • This alloy exhibits high ductility, demonstrated by an elongation rate of 33.82%. • The dissolution behaviour of the alloy is regulated by both gallium and tin elements. • The use of this material to make sealing tools can greatly improve the efficiency of extraction. • This material introduces a pioneering concept to the development of soluble metal composite materials. [ABSTRACT FROM AUTHOR]

This communication presents a dual-band aperture-shared high gain antenna for millimeter-wave (mm-wave) multi-beam and sub-6 GHz applications by integrating transmitarray into Fresnel zone plate (FZP) lens. The transmistarray consists of two sets of unit cells (UCs), which can provide high transmission magnitude and [ $-\pi $ , $\pi $ ] phase tuning at the mm-wave frequency band. Meanwhile, they show distinct transmission features at the sub-6 GHz band (one set of UC allows the electromagnetic (EM) wave to pass while the other prohibits the EM wave from passing). Then, by properly arranging the two kinds of UCs into the transparent and opaque region of the FZP lens respectively, the sub-6 GHz FZP lens and the mm-waveband transmitarray are integrated into the same aperture seamlessly. A waveguide-integrated patch antenna is adopted as the feed. The patch antenna operates at the sub-6 GHz band and three open waveguide antennas are used for the mm-wave multi-beam radiation. The proposed antenna achieves high gain at both bands with a reused radiating aperture. Mm-wave multi-beam radiation is obtained without an extra feeding network. For demonstration purposes, the central frequencies of the sub-6 GHz and the mm-wave bands are selected at 6 and 27 GHz, respectively. An antenna prototype is fabricated and experimentally verified. [ABSTRACT FROM AUTHOR]

An effective and simple synthesis of high-performance materials exerts a significant influence on low-cost commercial production with high production efficiency. In the present work, the effects of intrinsic factors on the microwave dielectric properties of reaction-sintering Mg 0.5 Zr 0.5 NbO 4 ceramics were quantified through crystal chemistry, Raman analysis, and bond characteristics. Pure-phase and low-loss Mg 0.5 Zr 0.5 NbO 4 ceramics were synthesized with an effective and simple reaction-sintering procedure. Detailed Raman vibrations with complete mode assignments were firstly investigated to characterize the lattice vibration. Rietveld refinement and Raman analysis confirmed the formation of pure-phase MgZrNb 2 O 8 ceramics even with the reaction-sintering process. Moreover, well-distributed microstructure with enhanced densification (nearly full density) was verified through SEM and element mapping. Through the chemical bond theory, the dielectric constant was dominated by the Nb–O bond ionicity (f i Nb-O). The Q × f was strongly related to the lattice energy (U Nb – O) and bond energy (E Nb-O) of the Nb–O bond, while the τ f value was influenced by the coefficient of thermal expansion of the Mg–O bond (α Mg-O), providing guidance for performance modification of Mg 0.5 Zr 0.5 NbO 4 systems. Excellent microwave dielectric properties for the samples sintered at 1350 °C: ε r = 28.6, Q × f = 82,000 GHz (7.1 GHz) and τ f = −47 ppm/°C were obtained via the reaction sintering process, exhibiting enormous potential for industrial production. [ABSTRACT FROM AUTHOR]

This communication proposes a dual-band antenna hybridizing a folded reflectarray antenna (FRA) and a folded transmitarray antenna (FTA). First, a polarization-rotation transmitarray is designed based on a new Fabry–Perot (FP)-liked phasing element. Unlike its counterparts, this new FP-liked phasing element twists the polarization of electromagnetic (EM) waves and provides sufficient phase tuning range only in the operating band of FTA. In the meantime, in the band of FRA, the transmitarray acts as the polarizing grid, which reflects one polarization while allowing the orthogonally polarized one to pass without affecting its polarization and phase. Second, a polarization-rotation-ground-integrated (PRGI) reflectarray is designed. The reflectarray collimates the EM wave in the band of FRA and twists its polarization by 90°, forming the folded reflectarray. Meanwhile, it also twists the polarization of the EM wave in the band of FTA. By hybridizing the FTA and FRA sharing the same aperture, the proposed design achieves dual-band high-gain radiation. To the best of our knowledge, this is the first time that the FRA and FTA are combined to form a shared aperture antenna, which inherits the advantages of both FRA and FTA, such as high gain, low profile, and reduced blockage effect of the feed. An antenna prototype is fabricated and measured to verify the idea. [ABSTRACT FROM AUTHOR]

Primary Objective • The aim of this study was to identify and understand the syndromes of mania in traditional Chinese medicine (TCM), as described in Chinese literature on the integrated treatment of mania using TCM and Western medicine. Methods • A literature search conducted in Chinese databases identified 27 articles that were included in a statistical analysis to determine the proportion of mania cases represented by various TCM syndromes. Results • After combining similar syndromes, we found that the TCM syndromes of mania could be categorized as phlegm-fire disturbance of the mind (Tanhuoraoshen), phlegm-heat stagnation (Tanreyujie), qi stagnation and blood stasis (Qizhixueyu), liver qi stagnation (Gandanyure), and fire injury Yin (Huoshengshnagyin). These syndrome categories accounted for 55.6%, 18.5%, 14.8%, 7.4% and 3.7% of mania cases, respectively. Manic symptom severity scores differed significantly among phlegm-fire disturbance of the mind (26.8 ± 1.6), phlegm-heat stagnation (31.1 ± 1.9), and qi stagnation and blood stasis (23.5 ± 2.2). Conclusion • The largest proportion of mania cases involved phlegm-fire disturbance of the mind, phlegmheat stagnation, or qi stagnation and blood stasis. Cumulatively, these syndromes accounted for 88.9% of cases; the severity of manic symptoms different significantly among the 3 syndrome categories. Smaller proportions of cases represented liver qi stagnation or fire injury Yin. [ABSTRACT FROM AUTHOR]

This article presents an aperture-shared dual-band large frequency-ratio high gain antenna for sub-6 GHz and millimeter-wave (mm-wave) bands applications. Initially, the partially reflective surface (PRS) of the Fabry–Pérot cavity (FPC) antenna operating at the sub-6 GHz band is realized by using single-layered periodic grid patches while the opaque region of the mm-wave bandwaveband Fresnel zone plate (FZP) lens antenna is implemented by using periodic double-screen dipoles. Then, the PRS and the FZP lens are hybridized together and upgraded into a kind of composite metasurface, which simultaneously functions as the PRS of the sub-6 GHz FPC antenna and the mm-wave bandwaveband FZP lens with little dual-band mutual interference. Thus, the FPC antenna and the FZP lens can share the same aperture with high aperture reuse efficiency. Because the principles are based on the FPC resonance and the collimating FZP lens, high gains are achieved at both bands without a feeding network. Meanwhile, a dual-band large frequency-ratio antenna is designed as the feed. A prototype working at 3 and 28 GHz bands is designed, fabricated, and measured to verify the idea. [ABSTRACT FROM AUTHOR]

Coastal aquaculture plays a crucial role in global food security and the economic development of coastal regions, but it also causes environmental degradation in coastal ecosystems. Therefore, the automation, accurate extraction, and monitoring of coastal aquaculture areas are crucial for the scientific management of coastal ecological zones. This study proposes a novel deep learning- and attention-based median adaptive fusion U-Net (MAFU-Net) procedure aimed at precisely extracting individually separable aquaculture ponds (ISAPs) from medium-resolution remote sensing imagery. Initially, this study analyzes the spectral differences between aquaculture ponds and interfering objects such as saltwater fields in four typical aquaculture areas along the coast of Liaoning Province, China. It innovatively introduces a difference index for saltwater field aquaculture zones (DIAS) and integrates this index as a new band into remote sensing imagery to increase the expressiveness of features. A median augmented adaptive fusion module (MEA-FM), which adaptively selects channel receptive fields at various scales, integrates the information between channels, and captures multiscale spatial information to achieve improved extraction accuracy, is subsequently designed. Experimental and comparative results reveal that the proposed MAFU-Net method achieves an F1 score of 90.67% and an intersection over union (IoU) of 83.93% on the CHN-LN4-ISAPS-9 dataset, outperforming advanced methods such as U-Net, DeepLabV3+, SegNet, PSPNet, SKNet, UPS-Net, and SegFormer. This study's results provide accurate data support for the scientific management of aquaculture areas, and the proposed MAFU-Net method provides an effective method for semantic segmentation tasks based on medium-resolution remote sensing images. [ABSTRACT FROM AUTHOR]

This communication proposes a new all-dielectric broadband dual-band reflectarray with a large frequency ratio using low-cost 3-D printing. In contrast to conventional reflectarrays using metallic resonant cells or dielectric slabs as phasing elements with full metal ground, the proposed design uses air as the phasing element and a stepped dielectric mirror structure as the ground. In this way, the metal ground is removed, which makes the design an all-dielectric one. Taking advantage of the dielectric mirror that only exhibits a bandgap in the predesigned band while allowing electromagnetic (EM) waves to pass through it at the frequency out of the bandgap region, a dual-band reflectarray is obtained. By properly selecting the bandgap frequency of the dielectric mirror, the dual-band frequency ratio is scalable and can be very large. Furthermore, instead of using a metallic or dielectric resonator based on resonance, air layers with linear phase response are adopted as the phasing element. Thus, the reflectarray shows broadband and stable performance over the dual-band. Compared with the state-of-the-art works using printed circuit boards (PCBs) or microfabrication, the proposed design is low cost and lightweight, and can be rapidly prototyped. For proof-of-concept, a prototype operating at $K$ -band and $V$ -band with a frequency ratio of 2.7 is printed and measured. [ABSTRACT FROM AUTHOR]

Fresnel zone plate (FZP) lens antenna, consisting of a set of alternative transparent and opaque concentric rings arranged on curvilinear or flat surfaces, have been widely used in various fields for sensing and communications. Nevertheless, the state-of-art FZP lens antennas are limited to a single band due to the frequency-dependent feature, which hinders their use in multi-band applications. In this work, a shared aperture dual-band FZP metalens antenna is proposed by merging two single-band FZP metalens antenna operating at distinct frequency bands seamlessly into one. Instead of using conventional metallic conductors, double-screen metagrids are devised in this work to form the concentric rings. Because the metagrids show distinct transmission/reflection properties at different frequencies, the performance of one set of concentric rings operating at the one band will not be affected by the other operating at the different band. In addition, to compensate for the phase shift introduced by the metagrids, an additional dielectric ring layer is added atop the FZP taking advantage of additive manufacturing. Thus, the radiation performance of the dual-band FZP lens antenna is comparable to that of each single FZP metalens antenna. For proof-of-concept, an antenna prototype operating at the dual band, 75 and 120 GHz with a frequency ratio of 1.6, is fabricated using an integrated additively manufactured electronics (AME) technique. The measured peak gains of 20.3 and 21.9 dBi are achieved at 75 and 120 GHz, respectively. [ABSTRACT FROM AUTHOR]

• Object: This paper further studied the unique characteristics of turbo-generator system, which is an important development direction of future aviation power. Aiming at the real runaway failure in the ground test, this paper expounded the root cause and direct cause of runaway failure, put forward the protection method of runaway failure and carried out the experimental verification, which provided the useful references for the configuration design and ground test of series hybrid aero propulsion system. • Method: As a whole, the paper adopted the iterative research method of "test-simulation-test". Firstly, it analyzed the real phenomenon of overspeed runaway failure in the engineering system, then established a simulation model to deeply study the causes of the failure, and finally carried out the feasibility analysis of the protective actions by combining simulation with test. The special highlight is that not only the corresponding solutions to the cause of failure were put forward in this paper，but also the experimental verification was included. • Conclusion: In this paper, the main conclusions of the research on runaway failure include:1) The fundamental cause of runaway failure lies in the small rotational inertia of high-speed turbo-generator set, and the direct cause is the unbalanced relationship between power supply and demand of the microgrid; 2) If the maximum power of battery meets the requirements, the failure risk can be eliminated by control methods; 3) Once the failure inevitably occurs, the resistors can be used to consume power to prevent the situation from getting worse. • Novelty: In this paper, the failure risk of turbine disk burst in a special application scenario was discovered through ground tests. Different from the traditional aviation power plant, the root cause and direct cause of the failure in the turbo-generator set were analyzed in detail, and a simulation model was established to support the viewpoint. Secondly, compared to the traditional mechanical designs, this paper skillfully solved mechanical problems by using control methods and electric methods. Finally, the test showed that the two protective actions can effectively avoid the overspeed runaway failure. • Significance: In order to meet the development goal of higher power density of turbo-generator system, in addition to the application of special motors, Permanent Magnet Synchronous Motors show a development trend of higher speed. The failure protective actions proposed in this paper can effectively avoid or delay the occurrence of runaway failure, improve the safety performance of the high-speed turbo-generator system, and lay the foundation for the development of series hybrid aero propulsion system with higher power and speed. Based on a series hybrid aero propulsion system with power class of 200 kW, voltage of 540 V and speed of 21000r/min, proceeding from the occurrence of the runaway failure during experiment, this study reveals the characteristics and causes of a traditional turbine engine failure in a new application context, focuses on optimizing mechanical issues from the perspective of control strategies and electrical equipment, combined with mechanism analysis and experimental validation. The main conclusions are as follows: the fundamental reason for the high-speed turbo-generator set facing the risk of overspeed runaway is the small rotational inertia of the rotor system, with the direct cause being the power imbalance between the supply side and the demand side of the propulsion system. Experimental verification demonstrated that the active protection scheme based on voltage regulation by battery can keep the speed and voltage of turbine-generator set fluctuations below 0.3 % and adjustment time within 0.5 s for load changes within the battery power range, effectively preventing runaway failures caused by minor power fluctuations. Additionally, the passive protection scheme based on power dissipation through resistors reduced the speed of the power turbine from 7000r/min to 2000r/min no more than 2 s, indicating the effectiveness of this measure in restricting the speed within a safe range. [ABSTRACT FROM AUTHOR]

New product presale is a strategic behavior of manufacturers to transfer inventory risks to consumers. The research purpose of this paper is to examine the presale discount, inventory, and service level decisions in an e-commerce supply chain, where the first period is the presale period and the second is the selling period for the new product. First, consumers were divided into two types—those who are risk averse and those who are not. Then, considering different presale discounts applied for new products, three presale strategy models were discussed: no-presale strategy, presale strategy with a moderate discount, and complete presale strategy, and the optimal decisions of e-commerce supply chain members were obtained under different valuations of the new product by consumers. Finally, the effects of the correlation coefficient between the numbers of the two types of consumers, the loss aversion degree of consumers, and the marginal profit in the sales period on the optimal discounted price and the maximum expected profit were analyzed. The conclusions of this article show that the presale strategy is not always optimal but depends on the parameters of the market and the type of consumers. For example, when the correlation coefficient between the two types of consumers is high, it is more profitable for the suppliers if they choose the presale strategy with a moderate discount, while e-commerce platforms tend to adopt the no-presale strategy. The optimal discounted price in the complete presale case is not necessarily lower than that in the moderately discounted presale case. If the marginal profit is high in the normal sales period or consumers are less averse to losses, suppliers are more likely to adopt the complete presale strategy. The research conclusions provide some theoretical reference for companies in the development of new product presale strategies in the e-commerce supply chain. [ABSTRACT FROM AUTHOR]

Background: COVID-19 has started to spread within China since the end of December 2019. As a special population, the pregnant and delivery women maybe influenced both in physical and psychological aspects. The meta-analysis was conducted about mental health in pregnant and delivery women.Methods: We searched both MEDLINE, EMBASE, Cochrane Library in English and CBM, CNKI, WANFANG and CSSCI in Chinese to find literature from December 2019 to 31 July 2020 related to COVID-19 and mental health in patient with pregnancy and delivery, among which results such as comments, letters, reviews and case reports were excluded. The prevalence of anxiety and depression in the population was synthesized and discussed.Results: A total of 11,187 subjects were included in 15 studies. Random effect model is used to account for the data by Revman 5.2. The results showed that the prevalence of depression was 30% (95% CI: 0.23-0.37), the prevalence of anxiety was 34% (95% CI: 0.26-0.43) and prevalence of both anxiety and depression was 18% (95% CI: 0.09-0.29). The prevalence of anxiety (OR = 2.15, 95% CI: 1.39-3.31, Z = 3.47, p=.0005), depression (OR = 1.95, 95% CI: 1.07-3.56, Z = 2.19, p=.03) were higher than that of controls. Significant heterogeneity was detected across studies regarding these prevalence estimates. Subgroup analysis was taken according to assessment tools, and sensitivity analysis was done to explore the sources of heterogeneity.Conclusions: The higher prevalence of depression, anxiety, both depression and anxiety in women with pregnancy and delivery during COVID-19 pandemic although the significant heterogeneity detected in studies. We must interpret the results with caution and also put attention to this result. As the epidemic is ongoing, it is vital to set up a comprehensive crisis prevention system. [ABSTRACT FROM AUTHOR]

The incorporation of nanosized pseudocapacitive materials and structure design are general strategies to enhance the electrochemical performance of MXene-based materials. Herein, the decoration of manganese dioxide (MnO 2) nanosheets on MXene (Ti 3 C 2 T x) surfaces was prepared by a facile liquid phase coprecipitation method. Ti 3 C 2 T x is initially modified by polydopamine (PDA) coating to ensure the homogeneous distribution of MnO 2 nanosheets and tight and close connections between MnO 2 and the Ti 3 C 2 T x backbone. Due to the obtained three-dimensional (3D) nanostructure, facilitating electron transport within the electrode and promoting electrolyte ion accessibility, the δ-MnO 2 @Ti 3 C 2 T x -0.06 electrode yields superior electrochemical performances, such as a rather large areal capacity of 1233.1 mF cm−2 and high specific capacitance of 337.6 F g−1 at 2 mV s−1, as well as high cyclic stability for 10000 cycles. Furthermore, δ-MnO 2 @Ti 3 C 2 T x -0.06 composites are employed as positive electrodes, and activated carbon (AC) materials act as negative electrodes with an aqueous electrolyte of 1 M Na 2 SO 4 to assemble asymmetric supercapacitors. The prototype device is reversible at cell voltages from 0 to 1.8 V, and manifests a maximum energy density of 31.4 Wh kg−1 and a maximum power density of 2700 W kg−1. These encouraging results show enormous possibilities for energy storage applications. A facile liquid phase coprecipitation method was used to design a manganese dioxide (MnO 2) nanosheets decorated MXene three-dimensional (3D) nanostructure with the aid of polydopamine (PDA) coating. Fast electron transport and electrolyte ions diffusion within the assembled device endows it with high electrochemical performance for practical application. [Display omitted] • PDA coating on Ti 3 C 2 T x surface can directly reduce MnO 4 − to δ-MnO 2 nanosheets and ensure their homogeneous distribution. • The obtained δ-MnO 2 @Ti 3 C 2 T x -0.06 electrode possesses a large areal capacity of 1233.1 mF cm−2 at 2 mV s−1. • The δ-MnO 2 @Ti 3 C 2 T x -0.06//AC device manifests a maximum energy density of 31.4 Wh kg−1 in the voltage range of 0−1.8 V. [ABSTRACT FROM AUTHOR]

Patient advocacy and media coverage are important strategies for changing health policies. China is no exception. Through 31 interviews and content analysis of 1,136 news stories related to hepatitis B, this study revealed how members of Chinese health advocacy groups strategically built a coalition with the news media, actively played the role of 'policy entrepreneurs', and successfully affected the framing of hepatitis B. As a result, China's grassroots civil societies not only successfully attracted public attention to the previously ignored problem of discrimination against people affected by hepatitis B but also impacted on the state's rewriting of public policies on this disease. [ABSTRACT FROM AUTHOR]

The SiC/Al–Mg–Si composite was obtained by in-situ synthesis, and the effects of Mg addition were investigated in this process. Mechanism of in situ SiC growth in the Resin–Al–Mg–Si system was investigated by fabricating and characterizing a SiC/Al–Mg–Si composite under moderate conditions. X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) were used to analyze the phase and its microstructure, with the aim of investigating the evolvement of grains in the alloy matrix. Mg 2 Si formed under higher Mg added conditions, which decreased the molten liquid and Si solute concentrations. Tiny amounts of MgO and MgAl 2 O 4 proved that the pyrolysis gas of resin reacts slightly with the matrix. The key conditions of in-situ synthesis SiC were found that the Mg addition and the Si concentration in the molten alloy were 3%–5% and over 17. 27 % respectively. Ostwald ripening was used to explain the decrease in tiny SiC grains at elevated temperatures. In situ SiC growth is controlled by the interfacial reaction-diffusion mixed model through two different routes in the molten alloy. Two modes of in-situ synthesis were suggested. The intermediate product and template for in situ SiC growth are Al 4 C 3 , and Si was shown to diffuse into its particles gradually. Flowing Si in molten alloy reacted with pyrolysis C directly. Specimens validated the peak bending strength with a rise in temperature. The maximal bending strength was 251.89 MPa. [ABSTRACT FROM AUTHOR]

This article presents a new linear-to-circular polarization conversion coding unit, on which two new kinds of beam-shaping lenses are proposed. First, under periodic boundary conditions, a linear-to-circular polarization conversion coding unit is introduced, which introduces the necessary phase delay by adjusting its geometrical parameters. The phase delay ranges from 0° to 360° and is discretized into 3 bit coding units corresponding to specific delays. Second, by properly arranging the coding units, a high-gain circularly polarized (CP) lens is proposed. The lens achieves linear-to-circular polarization conversion and beam collimation in the transmission mode simultaneously with a planar configuration, which is different from counterparts that place a lens atop of a polarizer. Furthermore, the coding units are used to form Wollaston-prism-like and Rochon-prism-like planar CP beam-shaping lenses, which split the beams with different polarizations into right- and left-handed components. These beams can be controlled independently. Prototypes working at 30 GHz band are designed, fabricated, and measured to verify the idea. [ABSTRACT FROM AUTHOR]

This communication presents a low-profile wideband and high-gain patch antenna array using low-temperature cofired ceramics (LTCCs) fabrication technique for 60 GHz applications. A coupled feeding scheme is adopted so that the antenna achieves wide impedance bandwidth that covers the entire 60 GHz license-free band with a height of only 0.384 mm (four tape layers). The shorting via connecting the upper patch and ground achieves the function of a virtual ac ground plane of differential feeding. This enables the antenna element to achieve good radiation performances, including stable gain (variation less than 1 dB) and a symmetrical beam with low cross-polarization over the entire frequency band. The performances of the antenna element are comparable to that of the differential-driven patch antenna while the complex differential feeding network is not required. Furthermore, the proposed antenna element with simple and easy-to-integrate geometry is successfully extended to a $4 \times 4$ antenna array using a substrate integrated waveguide (SIW)-based feeding network. The measured results show that the impedance bandwidth of the array covers the 60 GHz license-free band. The maximum gain can reach 16.7 dBi and the radiation performances are very stable over the operating frequency band. [ABSTRACT FROM AUTHOR]

Cataract is the leading cause of blindness in the world while the molecular mechanisms of cataracts pathogenesis are not well elucidated. Dysregulated microRNA (miRNA) expressions have been implicated in cataract. However, the precise role of miR‐4328 in cataract is still unknown. We compared the expression level of total miR‐4328 between clinical samples from healthy people and cataract patient and between UV‐irradiated and control lens epithelial cells. We determined the effect of miR‐4328 on lens epithelial cell proliferation and apoptosis by suppressing miR‐4328. We further predicted NLR Family Apoptosis Inhibitory Protein (NAIP) as potential target of miR‐4328 and continued to evaluate the effects of NAIP on cell proliferation and apoptosis. MiR‐4328 was up‐regulated in cataract sample and in UV‐irradiated lens epithelial cells. Suppressing MiR‐4328 promoted cell proliferation and inhibited apoptosis. MiR‐4328 targeted NAIP and suppressed its expression. Knocking down NAIP abolished the effects of miR‐4328 on cell proliferation and inhibited apoptosis. MiR‐4328 promotes lens epithelial cell apoptosis by targeting NAIP in age‐related cataract. Significance of the study: MiR‐4328 targeted NAIP and suppressed its expression. Knocking down NAIP abolished the effects of miR‐4328 on cell proliferation and inhibited apoptosis. MiR‐4328 promotes lens epithelial cell apoptosis by targeting NAIP in age‐related cataract. [ABSTRACT FROM AUTHOR]

Despite significant strides in digital classification of Chinese ink paintings, existing methods predominantly rely on low-level features, insufficient for capturing the nuanced artistic styles of such works. This study introduces a novel multi-branch residual network that leverages depth correlation features to enhance the classification of Chinese ink paintings. We innovatively combine global style features, extracted using the Gram matrix, with local brushstroke features obtained via the Holistically-Nested Edge Detection(HED) method. This dual-feature approach addresses the limitations of previous studies by incorporating high-level stylistic nuances alongside low-level details, resulting in a more robust classification system. Quantitative results demonstrate a marked improvement in classification accuracy, with our network outperforming existing state-of-the-art models by significant margins in both artist and genre classification tasks. This advancement not only underscores the efficacy of integrating diverse feature sets but also paves the way for more sensitive and accurate management of digital art repositories. [ABSTRACT FROM AUTHOR]

This paper describes a scoping review of China's academic resource databases, relevant official websites, news reports and public accounts spanning a period from the end of 2019 to the end of 2022, to investigate the challenges in scientific integrity and ethical soundness of research conducted during and immediately after the COVID-19 pandemic in China. By conducting the scoping review with keywords related to the research questions in Chinese, relevant data were extracted and classified into four categories: challenges in research, challenges in ethics review, challenges in publishing academic work, and research ethics guidelines during and after the pandemic. The paper points out that problematic studies and findings increased with the escalation in medical research projects during the pandemic in China. The situation faced by researchers was more difficult than before the pandemic. The mode of informed consent, and ethics review and oversight systems also underwent changes. In addition, Traditional Chinese Medicine as an alternative medical treatment for COVID-19, attracted attention from the research community and became a topic of discussion. We conclude that the various challenges and concerns identified indicate a need for a proper and timely response system be formulated in preparation for possible future occurrences of new pandemics or other critical situations. [ABSTRACT FROM AUTHOR]

Silicon‐bridged [1]ferrocenophanes are a versatile class of monomers to obtain well‐defined metallopolymers, however, their boron‐bridged analogues are far less utilized despite being significantly higher strained. We assumed that the reactivity of known bora[1]ferrocenophanes towards ring‐opening polymerization is hampered by π‐donating R2N groups at the bridging boron atom and therefore prepared the first bora[1]ferrocenophanes lacking such electronic stabilization. The new, isolated ferrocenophane with a 2,4,6‐triisopropylphenyl group attached to the bridging boron atom exhibits the most tilted Cp rings among all isolated strained sandwich compounds [α(DFT)=33.3°] with a measured record value of the bathochromic shift (λmax=516 nm). Attempts to purify the mesityl analogue by vacuum sublimation transformed this monomer to a purple‐colored polymer that resulted in Cotton effects in circular dichroism spectroscopy. DFT calculations revealed a left‐handed helical structure for this polymer. This is the first evidence for a polyferrocene with a chiral secondary structure. [ABSTRACT FROM AUTHOR]

Silicon‐bridged [1]ferrocenophanes are a versatile class of monomers to obtain well‐defined metallopolymers, however, their boron‐bridged analogues are far less utilized despite being significantly higher strained. We assumed that the reactivity of known bora[1]ferrocenophanes towards ring‐opening polymerization is hampered by π‐donating R2N groups at the bridging boron atom and therefore prepared the first bora[1]ferrocenophanes lacking such electronic stabilization. The new, isolated ferrocenophane with a 2,4,6‐triisopropylphenyl group attached to the bridging boron atom exhibits the most tilted Cp rings among all isolated strained sandwich compounds [α(DFT)=33.3°] with a measured record value of the bathochromic shift (λmax=516 nm). Attempts to purify the mesityl analogue by vacuum sublimation transformed this monomer to a purple‐colored polymer that resulted in Cotton effects in circular dichroism spectroscopy. DFT calculations revealed a left‐handed helical structure for this polymer. This is the first evidence for a polyferrocene with a chiral secondary structure. [ABSTRACT FROM AUTHOR]

This paper presents a new dual-band dual circularly polarized (CP) high gain patch antenna array for vehicle satellite communications. The array consists of 16 linearly polarized dual-band elements backed with a new frequency-selective-surface (FSS)-integrated polarization rotation ground. The polarization rotation ground is located underneath the array, which not only acts as a reflector to increase the array boresight gain but also enables the array's dual CP radiation. The electromagnetic (EM) waves reflected by the ground retard either 90° or 270° with respect to the EM waves of the array directly radiated to the upper sphere at two frequency bands, leading to the dual-band dual CP radiation. This is totally different from many of the former counterparts which are based on either the perturbation on the stacked patch or external feeding network. Measured results show the −10-dB impedance bandwidth is from 7.8 to more than 8.5-GHz for X-band and from 14 to 15.3-GHz for Ku-band. The 3-dB axial ratio bandwidth is from 8.15 to 8.35-GHz for the lower band (right-hand CP) and from 14.2 to 14.8-GHz for the higher band (left-hand CP), respectively. [ABSTRACT FROM AUTHOR]

This paper investigates the problem of exponential stability in mean square sense for stochastic Markov jump systems with mixed time-varying delays and partly unknown transition rates. By employing a class of appropriate stochastic Lyapunov functionals, the analysis process of stability for stochastic Markov jump systems can be effectively carried out. Based on the linear matrix inequalities technique, the mean square exponential stability criteria are presented for stochastic Markov jump systems with partly unknown transition rates. Furthermore, by expanding this case to uncertain Markov jump systems, we derive the sufficient conditions for guaranteeing the stability of uncertain Markov jump systems. A numerical example is presented to illustrate the effectiveness of the proposed results. [ABSTRACT FROM AUTHOR]

This paper presents new single-ended-fed planar aperture antennas (SPAAs) using low-temperature co-fired ceramics (LTCC) process technology. The SPAA element is proposed first, which not only inherits the merits of the aperture antennas including high gain and wide bandwidth but also exhibits advantages of low profile and compact size. The aperture is excited by a cross-shaped patch, and a loop-shaped balun structure placed below the patch is introduced to convert the single-ended signal into differential one to drive the patch. In this way, the energy can propagate on the patch in a traveling waveform and illuminate the aperture with uniform E-field distributions. Therefore, the antenna achieves good electrical and radiation performances, which are comparable to its balanced-fed counterparts, while processing a simplified structure. Measured results demonstrate that the impedance bandwidth of the antenna covers the 60 GHz license-free band (57–64 GHz), and the maximum gain can reach 11.5 dBi with a cavity area of only about 27 mm2. Furthermore, the element is successfully extended to a $4\,\,\times \,\,4$ element array using a substrate-integrated-waveguide based feeding network to further increase the gain up to 20.4 dBi. The measured results show that the impedance bandwidth of the array is from 57.5 to 65.7 GHz and the radiation performances are very stable over the operating frequency band. [ABSTRACT FROM AUTHOR]

The saturation input control problem of discrete-time networked systems via adaptive event-triggered communication scheme is discussed in this paper. The criteria are derived by utilising a new Lyapunov functional to guarantee that the considered networked system with randomly occurring infinite distributed delays, random packet losses and sensor saturation is exponentially stable in mean square sense. A novel adaptive event-triggered law is proposed, which is dependent on the exponentially stable index α. The effectiveness of our proposed method is illustrated by both theoretical analysis and numerical simulations. [ABSTRACT FROM AUTHOR]

Abstract This work was aimed to explore the relationship between phosphorus and coloring of copper glaze under oxidizing atmosphere. The phase, microstructure and chemical state of the samples were investigated by X-ray diffraction, Scanning electron microscopy, Raman spectroscopy and X-ray photoelectron spectroscopy. The results indicated that the addition of phosphorus broke up the silica network and decreased the viscosity of glaze melt, and then promoted the formation of discrete droplet phase-separated structures. Thus, blue opalescence was formed by the Rayleigh scattering on the sky-blue copper glaze surface. In addition, the reversed polarization of P5+ acted on the Cu–O bond and decreased the ratio of Cu2+ and Cu+. It increased the number of non-bridging oxygens and the spatial density of oxygen atoms around Cu2+, which was the essence of the copper blue glaze. Coupling of the structural color and the chemical color made the sky-blue copper glaze get more vivid. [ABSTRACT FROM AUTHOR]

Abstract Herein, we develop a fluoride-free hydrothermal etching approach using the small amounts of water-assisted potassium hydroxide as ingenious etching agents to produce novel two-dimensional Ti 3 C 2 (OH) 2 -MXene nanoribbons (Ti 3 C 2 (OH) 2 NRs). The as-produced Ti 3 C 2 (OH) 2 NRs possess less Al atoms, more abundant hydroxyl functional groups on their surface, and more open structure features compared with their pristine counterparts and the other etching products. Simultaneously, the resulting Ti 3 C 2 (OH) 2 NRs show significantly enhanced Li ions storage capabilities with outstanding specific capacity of 143.4 mA h g−1 obtained at 100 mA g−1 after 250 cycles, excellent cycling stability, and good rate property, being significantly superior than the parent Ti 3 AlC 2 phases and the sugarcane-like transitional etching products. The superior electrochemical properties of Ti 3 C 2 (OH) 2 NRs could be ascribed to the unique nanoribbon architectures with rich hydroxyl terminal groups and few Al atoms, which facilitates the adsorption and storage of a growing number of Li ions on the surface active sites of Ti 3 C 2 (OH) 2 NRs and the transport of electrons and ions effectively. What's more, this study provides a simple, effective, green, and nontoxic fluoride-free etching procedure to synthesize other more MXenes nanoribbons including but not limited to Ti 3 C 2 (OH) 2 NRs as promising anode candidates for advanced lithium-ion batteries. [ABSTRACT FROM AUTHOR]

The buzz evolution process of an axisymmetric supersonic inlet was investigated numerically and analyzed using the high-order dynamic mode decomposition (HODMD) method. Driven by an increasing back-pressure, the flow field evolves from a steady state to little buzz and then to big buzz. The computational dominant frequencies in the stages of little buzz and big buzz were basically consistent with those in the experiment. To analyze the buzz evolution of the global flow field quantitatively, the HODMD method was adopted to provide some dynamics information of modal amplitude and growth rate. During the buzz onset period, the disturbance from the oscillating shock gradually induces pressure fluctuation of the entire inlet. During the buzz transition, the shockwave dynamics at the entrance section of the inlet change first. When the amplitude of the big buzz mode exceeds that of the little buzz mode, the inlet is in the big buzz state, in which the pressure oscillation intensity in the downstream channel is significantly greater than that in the region swept by the shock at the entrance. During the buzz triggering and transition, the growth and attenuation rates of the little buzz mode are higher than those of the big buzz mode, suggesting that the little buzz is less stable than the big buzz. The appearance of high growth rates could be regarded as the precursor of the buzz triggering and the buzz transition. [ABSTRACT FROM AUTHOR]

This communication presents a new design of a quadri-polarization-agile aperture-coupled patch antenna array for 60 GHz applications. Four polarization states, namely, vertical linear polarization, horizontal linear polarization, left-hand circular polarization (LHCP), and right-hand circular polarization (RHCP) can be flexibly reconfigured by dynamically switching the excitation of the corresponding port. More importantly, as the LP and CP radiations are achieved by using differential feeding and sequential-rotation feeding, respectively, the array exhibits wide impedance and axial ratio (AR) bandwidths, high polarization purity as well as symmetrical pattern with the main beam fixed at boresight. The −10 dB impedance bandwidths are better than 11.6% (57–64 GHz) for the four polarization states. The measured AR bandwidths are from 58 to more than 64 GHz for both the LHCP and RHCP. The good radiation performance together with the quadri-polarization-agile capability of this new array, as demonstrated in the communication, underlines its suitability for the future 5G communication systems, especially in a multipath propagation environment. [ABSTRACT FROM AUTHOR]

Abstract A ternary MoO 3 /TiO 2 /Ti 3 C 2 T x composite was successfully prepared through in-situ oxidation of Ti 3 C 2 T x and loading of MoO 3 nanoparticles by one-pot hydrothermal method. The obtained ternary composite was characterized by X-ray diffraction, XPS, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). It could be clearly found that the TiO 2 nanoparticles and MoO 3 nanoparticles were well dispersed on the Ti 3 C 2 T x , larger TiO 2 nanoparticles were attached on the edges of Ti 3 C 2 T x layers and smaller MoO 3 nanoparticles were dispersed between Ti 3 C 2 T x layers. The nanoparticles extremely increase specific surface area of MoO 3 /TiO 2 /Ti 3 C 2 T x composite to 33.6 m2 g−1, and 9.8 m2 g−1 for as-prepared Ti 3 C 2 T x powder. Electrochemical properties testing results showed a specific capacitance of 162 F g−1 at a scan rate of 2 mV s−1 in the potential range from −1 V to −0.3 V with 1 mol L−1 KOH as electrolyte during the cyclic voltammetry (CV) cycles, which is superior to the performance of pure 2D layered Ti 3 C 2 T x. Also, the as-prepared ternary composites exhibited good specific capacitance retention of 91% after 8000 cycles. It is confirmed that the three components of ternary composites could make the integrated electrochemical behavior display and lead to a resulting capacitor with enhanced performance. The significant enhancement in electrochemical performance of the ternary composites can be attributed to the synergistic effect and cooperation of TiO 2 and MoO 3 nanoparticles dispersed on the Ti 3 C 2 T x sheets. Highlights • Tightly catching of TiO 2 nanoparticles and Ti 3 C 2 T x layers is important for electrical conductivity. • MoO 3 nanoparticles with high capacity also play an important role. • Ti 3 C 2 T x offers much active sites for electrochemical actions and nucleation-crystallization of TiO 2 and MoO 3 nanoparticles. [ABSTRACT FROM AUTHOR]

Most of manipulators possesses have drawbacks like only moving in fixed mode and intensity, cannot achieve self-adjusting and soft grabbing, etc. Herein, a four degree of freedom bionic manipulator based on multi-sensor data fusion technology is designed. The manipulator gathers electrical signal using piezoelectric sensor based on polyvinylidene fluoride (PVDF) film. A conditioning circuit is used to process signal. The manipulator is controlled to adjust grasping way according to orders that is obtained by data fusion. The manipulator achieves bionic function, which can grasp irregular and fragile object, also, it can bounce off automatically when approaching objects with high temperature. [ABSTRACT FROM AUTHOR]

This communication presents a new kind of substrate-integrated waveguide (SIW) slot antenna array with 1-D and 2-D monopulse radiation patterns. First, a new SIW magic-tee is developed, which exhibits a wide phase/amplitude balance bandwidth. Then, the magic-tee is extended to a new comparator which is used to feed the antenna with 2-D monopulse radiation pattern. Based on the proposed magic-tee and the comparator, 1-D and 2-D monopulse slot antenna arrays with $4\times 4$ elements are designed and measured, respectively. The experimental results show that the arrays exhibit good monopulse performance. More importantly, compared with their former counterparts, the monopulse performance of the arrays exhibits merely slight degradation over a much wider bandwidth due to the wide phase/ amplitude balance bandwidth that the comparators achieved. [ABSTRACT FROM AUTHOR]

The CoO/Ti 3 C 2 composite is prepared via a facile hydrothermal route followed by calcination, of which the morphology and the microstructure are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). CoO nanoparticles with the diameter of 10–20 nm are uniformly coated on the surface of Ti 3 C 2 nanosheets, which increases the surface areas and prevents the aggregation of CoO. In addition, the CoO/Ti 3 C 2 composite as an anode material for lithium-ion batteries (LIBs) demonstrates a higher initial discharge capacity of 1389 mAh g −1 with a columbic efficiency of 61% at 100 mAh g −1 . The reversible capacity can remain about 313 mAh g −1 after 100 cycles, which is much higher than that of the pure Ti 3 C 2 . The present results indicate that CoO/Ti 3 C 2 composite has a potential application in the anode of LIB. [ABSTRACT FROM AUTHOR]

A series of hybrid lacquer saps were prepared by adding copper(II)-modified montmorillonite (Cu(II)-MMT) into the raw lacquer. Cu(II)-MMT can effectively accelerate the polymerization of urushiol over a wide humidity range. Addition of 5 wt% of Cu(II)-MMT suspension (concentration, 5 wt%) into the raw lacquer sap made its touch-free drying time and hardened drying time decrease from each >36 days and >36 days to 6 days and 9 days at 36 °C and 50% relative humidity and from each >120 h and >120 h to 5 h 40 min and 23 h 30 min at 34 °C and 65% relative humidity, respectively. GPC tests proved the acceleration of the urushiol polymerization. Based on the results from UV–vis, FT-IR and NMR, the urushiol polymerization catalyzed by Cu(II)-MMT is similar to that catalyzed by laccase. However, a distinct difference is that the degree of crosslinking of lacquer films increased due to the formation of Si O C and Al O C bonds between urushiol and MMT in the drying process. Furthermore, addition of Cu(II)-MMT also improves the gloss and thermo-stability of lacquer films. [ABSTRACT FROM AUTHOR]

In this study, hexagonal mesoporous structured NiCo 2 O 4 with uniform size is successfully synthesized via a facile rotary evaporation. Hexagonal NiCo 2 O 4 electrodes exhibit a high specific capacitance of 568.0 F g −1 at 1 A g −1 , standout rate performance of 71.0% retention for current increases 16 times, and excellent cycling stability of 76.8% capacitance retention after 2000 cycles, which are attributed to interconnected mesoporous self-assembly architecture and larger specific surface area generated through the novel rotary evaporation. This strategy provides a new avenue to develop and broaden more mesoporous self-assembly functional materials. [ABSTRACT FROM AUTHOR]