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The net irrigation water requirement (NIWR) in the irrigated area is the “terminal” of water-use efficiency and the basis for implementing quota management and water-saving incentives. Also, it is significant for farmland water management and water conservation in irrigated areas. In light of the average water consumption per mu and the crop area, which are two key indicators of the NIWR, this paper adopts the field selection measurement method and the statistical method based on the image patches achieved by China’s third national land survey to acquire the data of water consumptions and crop areas. In this case, four principles of field selection are proposed, including “basic requirements”, “moderate size”, “controllable water inflow”, and “measurement practicality”, in an attempt to increase the number of fields selected for analysis. In addition, based on the image patches, the “complete investigation” and the “typical investigation” are suggested for irrigated areas at different scales to determine the crop areas, which are proven practicable and available for evaluating the water-use efficiency of irrigated areas at different scales.

It is of immense significance for agricultural water-saving work to stimulate the initiative of water users and enhance their water-saving awareness. Focusing on the southern water-lifting irrigation districts, this paper employs various water-saving potential analysis methods(water quota method and Irrigation test method) to calculate the water-saving potential of irrigation districts. The irrigation control indexes of the single-season rice trial in the experimental station adopt conventional irrigation mode. Based on irrigation test results, different water-saving grades are determined, and then, water-saving rewards are granted accordingly. The establishment of water-saving incentive systems shows positive effects on promoting water and energy conservation at pump stations, facilitating the benign operation of agricultural water conservancy projects.

Potassium‐ion batteries (PIBs) offer a cost‐effective and resource‐abundant solution for large‐scale energy storage. However, the progress of PIBs is impeded by the lack of high‐capacity, long‐life, and fast‐kinetics anode electrode materials. Here, we propose a dual synergic optimization strategy to enhance the K+ storage stability and reaction kinetics of Bi2S3 through two‐dimensional compositing and cation doping. Externally, Bi2S3 nanoparticles are loaded onto the surface of three‐dimensional interconnected Ti3C2Tx nanosheets to stabilize the electrode structure. Internally, Cu2+ doping acts as active sites to accelerate K+ storage kinetics. Various theoretical simulations and ex situ techniques are used to elucidate the external–internal dual synergism. During discharge, Ti3C2Tx and Cu2+ collaboratively facilitate K+ intercalation. Subsequently, Cu2+ doping primarily promotes the fracture of Bi2S3 bonds, facilitating a conversion reaction. Throughout cycling, the Ti3C2Tx composite structure and Cu2+ doping sustain functionality. The resulting Cu2+‐doped Bi2S3 anchored on Ti3C2Tx (C‐BT) shows excellent rate capability (600 mAh g–1 at 0.1 A g–1; 105 mAh g–1 at 5.0 A g–1) and cycling performance (91 mAh g–1 at 5.0 A g–1 after 1000 cycles) in half cells and a high energy density (179 Wh kg–1) in full cells. [ABSTRACT FROM AUTHOR]

Highlights: Heterostructure engineering is proposed to construct CoTe2/ZnTe heterostructures with built-in electric field. Conductive and elastic Ti3C2Tx MXene is introduced to improve the conductivity and alleviate the volume change of CoTe2/ZnTe upon cycling. The resulting CoTe2/ZnTe/Ti3C2Tx (CZT) demonstrates outstanding rate capability (137.0 mAh g−1 at 10 A g−1) and cycling stability (175.3 mAh g−1 after 4000 cycles at 3.0 A g−1). Moreover, the CZT-based full cells demonstrate excellent energy density (220.2 Wh kg−1) and power density (837.2 W kg−1). Exploiting high-rate anode materials with fast K+ diffusion is intriguing for the development of advanced potassium-ion batteries (KIBs) but remains unrealized. Here, heterostructure engineering is proposed to construct the dual transition metal tellurides (CoTe2/ZnTe), which are anchored onto two-dimensional (2D) Ti3C2Tx MXene nanosheets. Various theoretical modeling and experimental findings reveal that heterostructure engineering can regulate the electronic structures of CoTe2/ZnTe interfaces, improving K+ diffusion and adsorption. In addition, the different work functions between CoTe2/ZnTe induce a robust built-in electric field at the CoTe2/ZnTe interface, providing a strong driving force to facilitate charge transport. Moreover, the conductive and elastic Ti3C2Tx can effectively promote electrode conductivity and alleviate the volume change of CoTe2/ZnTe heterostructures upon cycling. Owing to these merits, the resulting CoTe2/ZnTe/Ti3C2Tx (CZT) exhibit excellent rate capability (137.0 mAh g−1 at 10 A g−1) and cycling stability (175.3 mAh g−1 after 4000 cycles at 3.0 A g−1, with a high capacity retention of 89.4%). More impressively, the CZT-based full cells demonstrate high energy density (220.2 Wh kg−1) and power density (837.2 W kg−1). This work provides a general and effective strategy by integrating heterostructure engineering and 2D material nanocompositing for designing advanced high-rate anode materials for next-generation KIBs. [ABSTRACT FROM AUTHOR]

Gradient structure design to improve impedance matching is one of the key methods to realize strong and broadband microwave absorption. However, almost all the reported gradient structures are multilayered and fabricated via a layer-by-layer process which is not applicable for mass production. Moreover, the bonding force between layers and bonding durability are usually weak, leading to potential material disassembly. Herein, a novel single-layer gradient structure (SLGS) is developed for the first time and successfully constructed via one-step gravity-induced sedimentation of Ni@Ti3C2Tx in a polyvinyl alcohol (PVA) matrix. Notably, the gradient can be easily tuned through changing the viscosity of the PVA solution. With an optimized gradient, the minimum reflection loss of Ni@Ti3C2Tx/PVA SLGS reaches −57.7 dB with an effective absorbing bandwidth of 3.2 GHz in the X band at a thickness of 2.22 mm. The impressive absorbing performance is ascribed to remarkable impedance matching which is demonstrated to be more crucial than attenuation ability. This work opens the mind to build an SLGS instead of a traditional multilayer gradient structure and offers a new idea to tune microwave absorbing performance through tuning filler distribution in the matrix. [ABSTRACT FROM AUTHOR]

The prosperous deployments of renewable energy have stimulated the looming exploration of K‐ion batteries (KIBs) for grid‐scale energy storage because of their high energy density and low cost. However, lacking advanced anode materials with high theoretical capacity, fast K+ storage kinetics, and eco‐friendliness discourages KIB development. Here, for the first time, ZnTe as an advanced KIB anode material with a conversion reaction mechanism (yZnTe + xK+ + xe− → yZn + KxTey) is demonstrated. The ZnTe nanoparticles are uniformly dispersed in a carbon matrix using metal–organic frameworks as starting materials, which are subsequently anchored on Ti3C2Tx MXene nanosheets, forming elaborate ZnTe@C/Ti3C2Tx (ZCT) nanohybrids. Various theoretical modeling and postmortem examinations reveal the synergistic integrations between carbon and Ti3C2Tx. Compositionally, they regulate the electronic structure of ZnTe, providing fast K+ adsorption kinetics. Morphologically, they construct a 0D/2D dual confinement, addressing the volume change of ZnTe upon cycling. Therefore, the ZCT exhibits a high capacity (408.0 mA h g−1 at 0.1 A g−1) and excellent long‐term cyclability (230.2 mA h g−1 at 1.0 A g−1 after 3500 cycles), outperforming other reported transition‐metal‐chalcogenides. Significantly, the ZCT‐based full cells achieve a high energy density of 110.3 Wh Kg−1, making ZCT promising for practical applications. [ABSTRACT FROM AUTHOR]