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[Objective] Whether “digitization” and “green” can cooperate is one of the important scientific issues in the field of high-quality development and high-level protection research. The Yangtze River Economic Belt, as a significant cluster of the digital industry and a key area for pollution reduction and carbon emission reduction coordination, plays a pivotal role in the construction of a beautiful China and the realization of the dual carbon goals. [Methods] Based on the equity investment data of the digital industry and the environmental pollution and carbon emission data from 108 cities in the Yangtze River Economic Belt between 2010 and 2020, this study delineated the spatial pattern of the digital industry and the spatial and temporal change characteristics of pollution reduction and carbon emission reduction. A fixed-effect model was employed to explore the impact of the digital industry agglomeration on pollution reduction and carbon emission reduction coordination and mechanism. Additionally, a spatial Durbin model was constructed to analyze its spatial spillover effects and attenuation boundaries. [Results] The findings reveal that: (1) The investment network of the digital industry in the Yangtze River Economic Belt exhibits a “multi-pathway, multi-polar” trend of spatial change, with net investment flows showing a clear tendency towards suburbanization, forming a “outflow from the center, receiving by the periphery” distribution pattern. (2) The agglomeration of the digital industry positively drives pollution reduction and carbon emission reduction, also demonstrating synergistic effects for both. This result remains robust after a series of endogeneity and robustness tests. Mechanism tests found that digital industry agglomeration can promote regional pollution reduction and carbon emission reduction coordination through scale economy effects, industrial upgrading effects, and technological innovation effects. (3) Digital industry agglomeration has a significant positive spatial spillover effect on pollution reduction and carbon emission reduction coordination. This effect presents a “right-tailed U-shaped” characteristic with increasing spatial distance. Meanwhile, the area within 250 km of the agglomeration is the “enhancement area” for spatial spillover effects, the area between 250 km and 450 km is the “attenuation area”, and beyond 450 km, the effect approaches zero and becomes insignificant. [Conclusion] Research has confirmed that leveraging the agglomeration effects of the digital industry can effectively promote synergistic improvements in regional pollution reduction and carbon emission mitigation.It is recommended to foster the agglomeration and networking development of the digital industry, encourage cross-regional investment in the digital industry, and implement differentiated strategies and cross-regional cooperation platforms.

Fiber-optic distributed acoustic sensing (DAS) promises great application prospects in smart grids due to its superior capabilities, including resistance to electromagnetic interference, long-distance coverage, high sensitivity and real-time monitoring. In this paper, we review the research progress and application status of DAS technology in power systems, focusing on its applications in areas such as the wind-induced vibration detection of transmission lines, partial discharge monitoring, transformer condition monitoring, and underwater cable and renewable energy transmission monitoring, as well as in the safety and protection of surrounding power facilities. Addressing the challenges currently faced by DAS technology in the smart grid, including detection accuracy, system cost, and data processing capability, this paper analyzes its major technical bottlenecks and proposes future research directions. [ABSTRACT FROM AUTHOR]

NASICON-type Na3.5V1.5Mn0.5(PO4)3 (NVMP) has been developed as a promising cathode material for sodium-ion batteries (SIBs). However, low-cost, environmentally friendly industrialization of NVMP is still limited. In this study, a nitrogen-doped carbon coated NVMP cathode material with enhanced conductivity as well as excellent rate performance was obtained by the suspensoid quick-drying method. Due to the advantage of the suspensoid quick-drying method, the mass prepared cathode material has fewer impurities, a more complete crystal structure, a more uniform carbon coating effect and better processing performance, which is conducive to improving the electrochemical performance and processability of the cathode, enhancing the cycling life and the energy density of the battery. Consequently, the electrochemical results show that compared with NVMP-2 obtained by the solid-state method, the as-prepared NVMP-1 cathode (more than 3 kg) exhibits an excellent rate performance of 80.2 mA h g−1 at 50C and an impressive capacity retention of 77.8% after 8000 cycles at 10C. DFT computations indicated that substituting V3+ with Mn2+ can enhance the crystal structure stability and electron conductivity. In addition, the assembled pouch cells display excellent low-temperature performance and cycling performance along with superior safety, which are much better than those of lithium-ion batteries (LIBs), suggesting that the NASICON-based pouch cells lay a foundation for the large-scale application of sodium-ion batteries. [ABSTRACT FROM AUTHOR]

The plasma jet wind tunnel, as a ground simulation device for studying the electromagnetic properties of near-space vehicle sheaths, can help people conduct several studies, such as communications and electronic parameter diagnostics. The plasma produced by a plasma generator has time-dependent variations due to the influence of power supply oscillations, turbulence, and other aspects of the device. To accurately define the experimental state of plasma, it is necessary to carefully analyze the three-dimensional (3D) time-varying characteristics of the plasma jet accurately since the distribution is non-uniform. This paper uses volume tomography technology to reconstruct the time series of the 3D emission field of the plasma jet with high-speed cameras. Then, the time–frequency characteristics, overall instability of the emission intensity, central axis position, and shape of the plasma jet are analyzed. The following characteristics are mainly observed: First, the plasma generator ejects plasma intermittently, which then spirals forward away from the nozzle. Second, the intensity, the radius of central axis movement, and the shape of the plasma jet vary with time at the same low frequency. The magnitude of this frequency is mainly related to the rate of change of the jet's air pressure difference with the vacuum chamber. Third, the overall instability of the plasma jet increases along the axial direction away from the nozzle and radially away from the center of the jet. [ABSTRACT FROM AUTHOR]

Biomass-derived carbon materials are widely studied and used in energy storage applications. Unfortunately, the disadvantages such as poor capacity and rate performance limit their development. Heteroatom doping can effectively improve the electrochemical properties of biomass-derived carbon materials. In this work, we designed and prepared environmentally friendly and cost-effective biomass (lotus root)-derived nitrogen-phosphorus (N–P) double-doped porous carbon spheres. When used as an anode material for a lithium-ion battery, the porous carbon spheres exhibited excellent stability performance (a reversible capacity of 739.6 mAh g−1 after 100 cycles at 0.1 A g−1 and 599.16 mAh g−1 after 215 cycles at 0.5 A g−1, respectively) and superior rate performance (a capacity of 187.22 mAh g−1 at 10 A g−1) due to the synergy of the heteroatomic doping and the layered porous spherical structure. The novel biomass-derived material based on N–P double-doped porous carbon spheres can serve as a cost-effective option for anode materials of lithium-ion batteries. Besides, an "adsorption-pore filling/intercalation" hybrid mechanism is proposed to understand the possible principle for superior lithium storage performance based on CV, ex-situ Raman and XRD results. [Display omitted] • N–P double-doped biomass porous carbon microspheres (LRNP) were prepared. • LRNP has excellent cycle capacity and rate performance for LIB application. • "Adsorption-pore filling/intercalation" mechanism of LRNP is revealed. [ABSTRACT FROM AUTHOR]