Efficient activation of molecular oxygen into reactive oxygen species is central to photocatalytic antibiotic degradation. Here, we prepared an edge-oriented CeO2 at the edges of carbon nitride (10-CeO2/CN) through a straightforward precursor adsorption followed by a hydrothermal process, where Ce is preferentially anchored at the CN edges. The 10-CeO2/CN achieves 89.2% tetracycline (TC) removal and 63.9% mineralization under visible-light irradiation, markedly outperforming pristine CN and CeO2. Experimental results and finite-element simulations demonstrate that edge-oriented CeO2 functions as an optical antenna for photon harvesting and a dielectric mirror to confine light at the interface, leading to 2.58-fold enhancements in the local optical field relative to CN and extending the photon propagation path and residence time. Density functional theory calculations further reveal that edge-oriented CeO2 exposes a highly reactive (200) facet, substantially enhancing O2 adsorption for activation. The enhanced interfacial optical field, coupled with facet-dependent O2 activation, enables the generation of singlet oxygen, thereby enabling efficient TC removal. These findings reveal the pivotal role of crystallographic orientation in coupling interfacial optical-field modulation with facet-dependent O2 activation, providing mechanistic insight into the rational design of high-performance photocatalysts for antibiotic degradation.
Ammonia (NH3) is a promising green hydrogen carrier, and its synthesis under mild, distributed conditions has attracted increasing attention. Non-thermal plasma provides a potential route for ammonia synthesis by enabling nitrogen activation through electron-driven processes. This study investigates catalyst-free NH3 synthesis in a flowing water-electrode dielectric barrier discharge (DBD) reactor driven by alternating current (AC), unipolar pulse, and bipolar pulse. Electrical diagnostics and optical emission spectroscopy were used to examine how excitation mode affects discharge behavior, energy utilization, and nitrogen activation. Nanosecond pulsed excitation improved NH3 synthesis performance compared with AC excitation under the tested conditions. Unipolar pulsing was more favorable in the low specific energy input (SEI) regime, whereas bipolar pulsing maintained better performance at higher SEI, which was associated with discharge regulation induced by periodic field reversal. Optical emission analysis indicated that bipolar excitation showed a slightly higher mean effective reduced electric field, together with stronger N2+-related emission. These results suggest enhanced electron-impact excitation and ionization characteristics and highlight the role of excitation waveform in regulating discharge behavior and energy utilization in catalyst-free plasma-assisted ammonia synthesis.
To investigate the influence of valve opening on the flow-induced noise in a DN100 double-bend pipeline system containing two 90° bends, a coupled DES–CA method was employed. The internal flow and induced noise were simulated at four valve openings (100%, 75%, 50%, and 25%). The results show that as the valve opening decreases, stronger throttling by the valve disc increases the pressure gradient across the valve and expands and intensifies the downstream region of high turbulent kinetic energy. Pressure pulsations become stronger, particularly downstream, where the high-pulsation region expands. The pressure pulsation spectrum exhibits discrete low-frequency components, especially downstream of the valve. As the valve opening decreases, the frequency of the characteristic line spectra increases, while the pressure pulsation autocorrelation weakens. The acoustic source strength increases significantly, and the area of high source intensity downstream of the valve gradually expands. At full opening, the acoustic energy is concentrated mainly at low frequencies. As the valve opening decreases, the low-frequency broadband characteristic becomes more pronounced, while spectral peaks associated with acoustic cavity modes emerge in the medium-to-high frequency range. The overall sound pressure level rises significantly, and high-sound-pressure-level regions expand and intensify. At downstream monitoring point P4, the overall sound pressure level increases by 44.66 dB as the valve opening decreases from 100% to 25%, providing a quantitative reference for low-noise operation of valve–pipeline systems.
The performance of direction of arrival (DOA) estimation, a cornerstone of array signal processing, is severely compromised in practical environments by non-Gaussian impulsive noise, which is common in systems like wireless communications and sonar. To address the applicability limitations of traditional second-order statistics in such environments, this paper introduces a novel polynomial correntropy operator (PCO). Specifically designed to handle covariance matrix divergence issues without requiring prior knowledge of noise characteristics, this operator significantly enhances practicality. Furthermore, by synergistically integrating PCO with nested array (NA) configurations, we develop a high-resolution arrival direction estimation algorithm. Comprehensive simulation validation demonstrates that under challenging conditions including strong impulsivity, low generalized signal-to-noise ratio (GSNR), and limited sampling, the proposed method achieves outstanding accuracy and robustness.
Poly(ethylene oxide) (PEO)-based electrolytes are critical for developing high safety and energy density of solid-state batteries, yet their practical application has been limited by low ionic conductivity and inadequate high-voltage stability. To address these challenges, we introduce an active sodium-based filler, Na5 YSi4 O12 (NYSO), into the PEO(Li+ ) electrolyte to fabricate a hybrid solid electrolyte (HSE). This strategy leverages the intrinsic dynamic disparity between Na+ in NYSO and Li+ in PEO to create a highly active ion-exchange interlayer at the organic-inorganic interface. Through advanced solid-state NMR combined with Raman spectroscopy, we demonstrate that this interphase markedly enhances ion transport dynamics, as evidenced by a low Li+ transport barrier of 0.08 eV, an increased amorphous fraction of 75.3 %, and an elevated free-ion ratio of 14.6 %. Consequently, the HSE can operate effectively at 50 degrees C, delivering an ionic conductivity of 3.92 & times; 10-4 S/cm and a Li+ transference number of 0.68. NCM811||Li full cells retain 80.1 % of their initial capacity after 200 cycles at 0.3 C. This design strategy offers a viable route to tailoring the local interfacial environment between inorganic and organic components in HSEs. V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.
