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In this paper, a novel heterogeneous 8-core fiber, with a standard cladding diameter of 125 μm, is proposed for C-band transmission. The structural parameters of 8-core fiber have been meticulously optimized through the utilization of an artificial intelligence-based algorithm, which resulted in a notable decrease in crosstalk and confinement loss, as the effective mode area of each core is sufficiently large to partially suppress the accumulation of nonlinear effects. The designed 8-core fiber was manufactured by traditional plasma chemical vapor deposition process. Besides, in order to implement the optical interconnection between single-mode fiber and 8-core fiber, a pair of corresponding fan-in/fan-out devices with low insertion loss have also been developed. The maximum crosstalk of designed 8-core fiber was measured to be -52.9 dB/10 km at 1550 nm. Finally, using these fan-in/fan-out devices, we successfully demonstrated a 1.6Tbps (4x400G) self-homodyne coherent detection transmission in C-band over 10 km, and the transmission characteristics were evaluated using a PDM-16QAM transceiver.

Single-crystalline cathode materials LiNixCoyMn1–y–zO2(x≥ 0.6) are important candidates for obtaining better cyclic stability and achieving high energy densities of Li-ion batteries. However, it is liable to initiate phase transitions inside the grains during electrochemical cycling, and the processes and regions of these phase transitions have remained unknown. In this research, we conducted an intrinsic study, investigating the chemicals and microstructural evolution of single-crystalline LiNi0.83Co0.11Mn0.06O2using in situbiasing transmission electron microscopy at an atomic scale. We observed that the layered structure on the surface of the single-crystalline material was degraded during the charging process, resulting in continuous phase transitions and the formation of surface oxygen vacancies, which can reduce both the structural and thermal stability of the material. Uneven delithiation led to the formation of high-density defects and discontinuous inactive electrochemical phases, such as local antiphase boundaries and the rock salt phase, in the bulk of the material. The non-uniformity of the structure and the coexistence of active and inactive phases introduce significant tensile stress, which can lead to intragranular cracks inside the grains. As the number of cycles increases, the structural degradation caused by the intragranular phase transition will further increase, ultimately affecting the cycling capacity and stability of the battery. This work has broad implications for creating lithium-ion batteries that are effective and long-lasting.

The utilization of anionic redox chemistry provides an opportunity to further improve the energy density of Li-ion batteries, particularly for Li-rich layered oxides. However, oxygen-based hosts still suffer from unfavorable structural rearrangement, including the oxygen release and transition metal (TM)-ion migration, in association with the tenuous framework rooted in the ionicity of the TM–O bonding. An intrinsic solution, by using a sulfur-based host with strong TM–S covalency, is proposed here to buffer the lattice distortion upon the highly activating sulfur redox process, and it achieves howling success in stabilizing the host frameworks. Experimental results demonstrate the prolonged preservation of the layered sulfur lattice, especially the honeycomb superlattice, during the Li+extraction/insertion process in contrast to the large structural degeneration in Li-rich oxides. Moreover, the Li-rich sulfide cathodes exhibited a negligible overpotential of 0.08 V and a voltage drop of 0.13 mV/cycle, while maintaining a substantial reversible capacity upon cycling. These superior electrochemical performances can be unambiguously ascribed to the much shorter trajectories of sulfur in comparison to those of oxygen revealed by molecular dynamics simulations at a large scale (∼30 nm) and a long time scale (∼300 ps) via high-dimensional neural network potentials during the delithiation process. Our findings highlight the importance of stabilizing host frameworks and establish general guidance for designing Li-rich cathodes with durable anionic redox chemistry.

Quantifying how climate factors affect vegetation phenology is crucial for understanding climate-vegetation interactions and carbon and water cycles under a changing climate. However, the effects of different intensities of extreme climatic events on vegetation phenology remain poorly understood. Using a long-term solar-induced chlorophyll fluorescence dataset, we investigated the response of vegetation phenology to extreme temperatures and precipitation events of different intensities across the Tibetan Plateau (TP) from 2000 to 2018. We found that the effect of maximum temperature exposure days (TxED) and minimum temperature exposure days (TnED) on the start of the growing season (SOS) was initially delayed and shifted to advance along the increasing temperature gradients. However, the response of the end of the growing season (EOS) to TxED and TnED shifted from an advance to a delay with increasing temperature gradients until the temperature thresholds were reached, above which thresholds produced an unfavorable response to vegetation growth and brought the EOS to an early end. The corresponding maximum and minimum temperature thresholds were 10.12 and 2.54°C, respectively. In contrast, cumulative precipitation (CP) was more likely to advance SOS and delay EOS as the precipitation gradient increased, but the advance of SOS is gradually weakening. Four vegetation types (i.e., forest, shrubland, meadow, and steppe) showed similar trends in response to different climates, but the optimal climatic conditions varied between the vegetation types. Generally, meadow and steppe had lower optimal temperatures and precipitation than forest and shrubland. These findings revealed the divergent responses of vegetation phenology to extreme climate events of different intensities, implying that the SOS will continue to advance with warming, whereas the EOS may undergo a partial transformation from delayed areas to advanced areas with continued warming.

Onboard image data management and sharing are the foundations for achieving cooperative data processing and analysis in multiple unmanned aerial vehicles (multi-UAVs). However, various challenges, such as the lack of efficient onboard data indices, restrict the development of multi-UAV cooperative applications. Here, we propose a novel and versatile cooperative data management framework based on a discrete grid system for multi-UAV onboard image data. First, we study the image coding methodology employed within the proposed framework. This method transforms original spatiotemporal and attribute information in images into well standardized and structured coded information. Second, we introduce a grid-based onboard image data management (Grid-OIM) approach to facilitate cooperative data management among multi-UAVs using code-based index and query methods. Finally, we applied Grid-OIM to cooperative image localization tasks. Experiments were conducted using an edge-computing platform and an embedded database. The image coding method could process >12000 images/s while maintaining excellent real-time performance. Moreover, the efficiency of creating and updating the image data index and querying the image data increased by averages of 17.6, 9.3, and 66.1 times, respectively, compared to the image data management method based on $\text{R}^{\ast} $ -Tree, highlighting the substantial advantages of this proposed method. These improvements address the demands of indexing and querying highly dynamic onboard image data effectively. Furthermore, the horizontal accuracy of image localization calculated by the cooperative localization method was improved by 43.4%–81.6% compared to that of a single UAV, enhancing reliability. Overall, Grid-OIM presents a feasible and practical solution for multi-UAV cooperative applications.

Sulfamethoxazole (SMX) is a representative sulfonamides that has been widely detected in various waters, and posing adverse effects on ecological safety and human health even at trace level. Various metal salts of ZnCl2, MnCl2and MgCl2were applied to activate the special biochar derived from sludge (SBC), and ZnCl2functionalized SBC (ZnSBC) exhibited the optimal removal capacity for SMX. Then, ball milling coupled with ZnCl2was used to co-functionalize SBC to produce BZnSBC for further improving its adsorption ability. The maximum adsorption ability of BZnSBC (6.05×104μg/g) for SMX was 8.27 times that of SBC, and it exhibited the optimum adsorption performance in the pH rang of 3–5. The outstanding elimination effect of SMX by BZnSBC (its elimination rates ranged from 90.7 % to 98.1 % in diverse real waters) was attributed to its high anti-interference to a wide range of pH, salts and humic acid concentrations. Characterization, adsorption experiments, models fitting together with DFT calculation demonstrated that π-π conjugation, pore filling, H-bonding and Zn-O complexation were the primary driving forces for SMX binding to BZnSBC. NaOH could efficiently regenerate the used BZnSBC and its adsorption capacity was 99.8 % of the original one in the fifth cyclic experiment. Also, BZnSBC performed favorable safety in view of the low leaching risk of Zn despite of pH, salts and humic acid concentrations range.

This study presents a novel approach to extracting rare earth elements (REE) from fly ash (FA) using environmentally adapted microbial consortia, highlighting a sustainable alternative to traditional extraction methods. Through comprehensive geochemical characterization of FA obtained from a power plant in China, a complex matrix rich in REE was identified. Microbial consortia isolated from both sludge and FA demonstrated distinct and interactive communities with specialized adaptations for REE bioweathering, as revealed by metagenomic analysis and molecular ecological network assessments. These communities exhibited diverse metabolic profiles, emphasizing ion transport, energy production, and carbohydrate and lipid metabolism tailored to their specific environmental contexts. Enzymatic profiling further elucidated the critical roles of siderophore production and redox reactions in the bioweathering process. Ex-situ bioweathering experiments showcased the consortia's capability to efficiently mobilize specific REE. Notably, under optimized conditions (10 % inoculum of Sludge_LB at 30 °C), significant extraction efficiencies were observed, such as 0.119 mg/g for Sc and 0.068 mg/g for Y; similarly, 10 % inoculum of FA_M9 at 30 °C showed an extraction efficiency of 0.036 mg/g for La. Recovery rates for various REE ranged from 29 % to 83 %, were obtained in a short time (48 hours) demonstrates the effectiveness of this method. These results demonstrate the sustainability of microbial consortia for REE extraction, offering reduced environmental impact compared to conventional methods. This research not only provides a viable method for REE recovery from industrial waste but also contributes to broader goals of sustainable resource utilization and environmental protection.

The in-depth promotion of national fitness provides an opportunity for the development of community sports events, but it still faces multiple difficulties in practice. This paper adopted the method of literature materials and expert interviews. On the basis of clarifying the development elements of community sports events, it conducts research by constructing a "resource-mechanism-structure" analysis framework. Community sports events are jointly determined by the basic resources, the state of the operating mechanism and the state of the supporting structure. In view of the current practical problems such as insufficient stock of basic resources for community sports events in China, backward practice of guarantee mechanism, unbalanced supporting structure, etc., it is considered that to solve the resource dilemma of community sports events, it is necessary to build around key elements such as venue facilities, sports instructors and community sports foundations. To solve the institutional dilemma, we need to focus on improving the risk management mechanism, incentive mechanism and negotiation mechanism; To break through the structural predicament, it is necessary to grasp the important contents such as competition supply mode, residents' interest-related awareness, community sports competition alliance and so on. [ABSTRACT FROM AUTHOR]

The rotation vector of the matrix converter has the characteristic that the common mode voltage is zero, so the direct torque control (DTC) strategy using the rotation vector can effectively suppress the common mode voltage of the motor system. However, because the direction of the rotation vector is constantly changing and the distribution is extremely uneven, the existing DTC based on the rotation vector not only has a complicated switching table, but also increases the torque ripple and current harmonics. In this paper, a novel direct torque control strategy using virtual rotation vectors is proposed. The virtual rotation vector is synthesized by the rotation vector with identical rotating direction, and the duty cycle of the selected rotation vector is theoretically derived and calculated, leading to six evenly distributed virtual rotation vectors with fixed relative positions, and therefore a simple-form switching table can be easily constructed. The proposed control strategy is experimentally verified, and the results show that, compared with the traditional rotation vector-based DTC, the proposed strategy not only achieves zero common-mode voltage, but also significantly reduces torque ripple and current harmonics, improving the steady-state performance of the motor system.

The internet of things (IoT) connects numerous physical devices in urban areas to implement smart cities, and health monitoring has emerged as the most promising application area in such cities. However, the current health monitoring solution heavily relies on cloud-based data centres to integrate data, which put the city's confidential data and user's private information at risk of leakage. Fog computing as an extension of cloud computing has attracted lots of attention in the IoT community, for its safety to local data and friendliness to time-sensitive applications. This article adopts the paradigm of fog computing and proposes the cognitive fog for health (CFH) to address the requirement of estimating urban-level health impact in the real-world scenario.

Researchers have been seeking for the most technically‐economical water electrolysis technology for entering the next‐stage of industrial amplification for large‐scale green hydrogen production. Various membrane‐based electrolyzers have been developed to improve electric‐efficiency, reduce the use of precious metals, enhance stability, and possibly realize direct seawater electrolysis. While electrode engineering is the key to approaching these goals by bridging the gap between catalysts design and electrolyzers development, nevertheless, as an emerging field, has not yet been systematically analyzed. Herein, this review is organized to comprehensively discuss the recent progresses of electrode engineering that have been made toward advanced membrane‐based electrolyzers. For the commercialized or near‐commercialized membrane electrolyzer technologies, the electrode material design principles are interpreted and the interface engineering that have been put forward to improve catalytic sites utilization and reduce precious metal loading is summarized. Given the pressing issues of electrolyzer cost reduction and efficiency improvement, the electrode structure engineering toward applying precious metal free electrocatalysts is highlighted and sufficient accessible sites within the thick catalyst layers with rational electrode architectures and effective ions/mass transport interfaces are enabled. In addition, this review also discusses the innovative ways as proposed to break the barriers of current membrane electrolyzers, including the adjustments of electrode reaction environment, and the feasible cell‐voltage‐breakdown strategies for durable direct seawater electrolysis. Hopefully, this review may provide insightful information of membrane‐based electrode engineering and inspire the future development of advanced membrane electrolyzer technologies for cost‐effective green hydrogen production. This review summarizes the cutting‐edge electrode engineering strategies, including electrode structure engineering, interface engineering, catalyst utilization improvement, electrode reaction environment regulation, cell‐voltage‐breakdown strategy, and so on toward the most promising commercialized, near‐commercialized, and advanced membrane water electrolyzer technologies, aiming to achieve efficient, durable, and economical green hydrogen production through water electrolysis.

A single-atom catalyst is a supported material in which the active phase is presented as isolated atoms. Single atom photocatalytic degradation of micropollutants has garnered significant attention in recent research. However, updated their performance of isolated is still limited. This review paper presents key aspects related to the use of SACs in micropollutant degradation: The performance influencing factors like material structure, surface area, surface density, relative humidity, temperature airflow, light intensity and reactants concentrations are also discussed. Further still synthesis methods including atomic deposition, ball milling, atomic trapping, pyrolysis, two steps doping, wet impregnation, facile deposition, electrostatic adoption are updated. Characterization techniques like STEM, TEM, FTIR, XAS, XRD, XPS, DFT are evaluated in relation to SACs quality with an emphasis on photocatalytic performances in micropollutant destruction as well as their applications. Single atom catalysts are endowed with uniform, definite metal active centers and tunable matching options, which give them excellent photocatalytic vigor and special selectivity for defined applications. In addition, photocatalytic mechanism of light harvesting, charge transfer and separation, applications of single atom micropollutants, photocatalysts support combinations with other materials and technologies as well as challenges like stability and recyclability, metal loading, nature of carrier, structure and future perspective are discussed. Finally highlighted the conclusion remarks on the performance keynote areas.

Recent years of intense efforts have seen an increasing interest in heterogeneous nanocomposites, which usually exhibit enhanced catalytic properties due to the synergistic effect among their different domains. Among the heterogeneous nanocomposites, those consisting of noble metals and semiconductors are particularly attractive for catalyzing electrochemical reactions. We herein focus on introducing the latest developments in noble metal-based nanocomposites consisting of Pt/Pd and semiconductor/metal oxide. In this review, we emphasize the applications of noble metal-based nanocomposites as electrocatalysts for electrochemical reactions including methanol oxidation reaction, formic acid oxidation reaction, and oxygen reduction reaction. We would lie to briefly narrate the fundamentals/principles of the noble metal-based nanocomposites as catalysts for electrochemical reactions, and prefer to summarize the noble metal-based heterogeneous nanocomposites developed most recently viasolution-based strategies, including their synthesis, characterization, and applications and perspectives in electrocatalysis so as to provide the readers insights in designing efficiently composite electrocatalysts for next stage.

Structure and surface modification of electrocatalysts demonstrates a promising lead for achieving excellent electrocatalytic activity and efficiency. Among various surface modification strategies, nonthermal plasma technique possesses an irreplaceable role due to the merits of simple but controllable operation procedure, low pollution, low cost, and easy scale‐up for practical applications. Nonthermal plasma treatment, as a powerful tool for material surface and structural engineering, can mainly benefit the electrocatalytic reactions in the following aspects: surface atom doping or reconstructing, introducing vacancies or defects, surface partially reducing or oxidizing, and increasing the porosity or roughness. Given to its flexibility, plasma modification is gaining a noticeable popularity, and great progress has been made in applying plasma for optimizing surface properties of the mainstream electrocatalysts, including metal‐free carbon materials, metal oxides, and other compounds, as well as organometallic electrocatalysts, etc. This review first summarizes the recent advances in nonthermal plasma modification for achieving desirable electrocatalytic behaviors, aiming to highlight the cutting‐edge function designs of electrocatalysts with plasma technology. It is hoped that this work can give some inspiration for the development of highly efficient electrocatalysts. Plasma modification provides a feasible way for optimizing the chemical/physical properties of the electrocatalysts, including doping with heteroatom functionalities, reorganizing surface atoms, partially reducing/oxidizing the active sites, and introducing vacancies and/or defects to the active surface. This surface modification technique is suitable in regard to the mainstream electrocatalysts, including metals, carbons, metal compounds, as well as organic materials.

To experimentally verify the Si oxidation reaction model mediated by point defect (emitted Si atoms and their vacancies) generation due to oxidation-induced strain, real-time photoelectron spectroscopy using synchrotron radiation was employed to simultaneously evaluate the amount of oxidation-induced strained Si atoms at the SiO2/Si interface, oxidation state, and oxidation rate during oxidation on n-type Si(001) surfaces with O2gas. It is found that both the oxidation rate and the amount of strained Si atoms at the completion of the first-oxide-layer growth decrease gradually with increasing temperature from 300 to 550 °C, where the oxide grows in the Langmuir-type adsorption manner. It is found that the interface strain and oxidation rate have a strong correlation. We discuss the reason for the oxide coverage and oxidation temperature dependences of interfacial strain from the viewpoint of the behavior of adsorbed oxygen during the first-oxide-layer growth.