Publications by authors named "Weigen Chen"

Background: The concentration of natural gas components significantly impacts the transportation, storage, and utilization of natural gas. Consequently, implementing online monitoring and leak detection systems is vital to guarantee the efficient use of natural gas and to uphold its safe and stable operation. Raman spectroscopy offers distinctive benefits, including high selectivity, superior precision, and the capability to detect multiple gas components simultaneously using a single-wavelength laser.

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Dynamic detection of multiple CFO decomposition gases can more comprehensively and effectively evaluate the operating status of eco-friendly gas-insulated power equipment (GIPE), which is a technical support for promoting the construction of eco-friendly, low-carbon energy power systems. In this article, we propose a silicon noise suppression fiber-enhanced Raman spectroscopy (FERS) technique and design a FERS sensing system for the dynamic detection of multiple CFO decomposition gases. Benefiting from the effective hybrid silicon noise filtering technology, the spectrum noise of FERS can be suppressed by 90% and the system detection sensitivity can be improved by 4.

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Assessing the levels of furfural in insulating oils is a crucial technical method for evaluating the degree of aging and mechanical deterioration of oil-paper insulation. The surface-enhanced Raman spectroscopy (SERS) technique provides an effective method for enhancing the sensitivity of in-situ detection of furfural. In this study, a homogeneous three-dimensional (3D) urchin-like Au@WO heterostructure was synthesized as a SERS substrate using a straightforward hydrothermal method.

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The feasibility of aqueous zinc-ion batteries for large-scale energy storage is hindered by the inherent challenges of Zn anode. Drawing inspiration from cellular mechanisms governing metal ion and nutrient transport, erythritol is introduced, a zincophilic additive, into the ZnSO electrolyte. This innovation stabilizes the Zn anode via chelation interactions between polysaccharides and Zn.

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Accurate detection of dissolved furfural in transformer oil is crucial for real-time monitoring of the aging state of transformer oil-paper insulation. While label-free surface-enhanced Raman spectroscopy (SERS) has demonstrated high sensitivity for dissolved furfural in transformer oil, challenges persist due to poor substrate consistency and low quantitative reliability. Herein, machine learning (ML) algorithms were employed in both substrate fabrication and spectral analysis of label-free SERS.

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In this work, a SiO doped polyvinyl alcohol/polyethylene glycol (PVA/PEG) gel polymer electrolyte (PVA/PEG-SiO) was constructed an ice-crystal template for zinc-ion batteries. The SiO and the three-dimensional porous skeleton make it have excellent ionic conductivity and mechanical strength, and inhibit the growth of dendrites. The assembled ZIBs exhibit excellent rate performance and cycle stability, making it a promising electrolyte membrane candidate for flexible wearable electronics.

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The aging characteristic components of oil-paper insulation reflect the aging status of the power equipment. In this study, we designed a novel microfluidic chip capable of automatic and rapid extraction of aging components from insulating oil. Combined with Raman spectroscopy technology, it enables simultaneous detection of various aging components.

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Article Synopsis
  • The challenges of directly reflected fields in optical feedback systems complicate spectroscopy and reduce sensitivity, with mechanisms not fully understood.
  • This study introduces a new analytical model to address these issues and suggests parameters that can achieve frequency locking and optimize performance.
  • Experimental results validate the approach, demonstrating that it can mitigate negative effects without compromising overall system functionality, potentially enhancing cavity-enhanced spectroscopy and high-purity diode laser development.
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Rechargeable Zn-MnO batteries using mild water electrolytes have garnered significant interest owing to their impressive theoretical energy density and eco-friendly characteristics. However, MnO suffers from huge structural changes during the cycles, resulting in very poor stability at high charge-discharge depths. Briefly, the above problems are caused by slow kinetic processes and the dissolution of Mn atoms in the cycles.

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Article Synopsis
  • * An FBG sensor was designed to monitor both strain and temperature, allowing for a detailed understanding of how Li-ion batteries behave under different conditions.
  • * The study revealed that charging and discharging release heat, with discharging generating more heat than charging, while strain on the battery's surface varies due to electrochemical changes and thermal expansion.
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To achieve omnidirectional sensitive detection of partial discharge (PD) in transformers and to avoid missing PD signals, a fiber optic omnidirectional sensing method for PD in transformers combined with the fiber Bragg grating (FBG) and Fabry-Perot (F-P) cavity is proposed. The fiber optic omnidirectional sensor for PD as a triangular prism was developed. The hollow structure of the probe was used to insert a single-mode fiber to form an F-P cavity.

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Oil-paper insulated equipment is integral in power conversion and supports low-loss electricity transport. As a characteristic byproduct of the oil-paper insulation system, the realization of efficient detection of furfural in oil is crucial to the safe operation of the power grid. We proposed a novel approach using dual-enhanced Raman spectroscopy for sensing trace liquid components.

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Evaluating the transformer aging state and detecting multi-aging characteristics in transformer oil with high sensitivity and fast speed has become a key challenge. This study introduces a P-N heterojunction (CNTs@NiO-α-FeO) fabricated through electroless nickel plating and a one-step hydrothermal method. Additionally, silver nanoparticles (AgNPs) with adjustable particle sizes are grown on the surface using a chemical reduction method.

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CH and H, as important chemical and energy raw materials, can be produced effectively and environmentally friendly by the partial oxidation (POX) of CH. Simultaneous analysis of intermediate gas compositions in the multiprocess (cracking, recovery, degassing, etc) of POX can regulate product generation and improve production efficiency. To overcome the disadvantage of common gas chromatography, we propose a fluorescence noise eliminating fiber-enhanced Raman spectroscopy (FNEFERS) technique for simultaneous and multiprocess analysis of the POX process, in which the fluorescence noise eliminating (FNE) method can effectively eliminate the horizontal and vertical spatial noise to ensure ppm level limits of detection (LOD).

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Gaseous impurities contained in hydrogen (H) profoundly affect the performance of hydrogen proton-exchange membrane fuel cells. We demonstrate the utility of cavity-enhanced Raman spectroscopy as a unique approach for detection of gaseous impurities. A dense-pattern multipass cavity which is composed of four spherical mirrors placed in a Z-shaped configuration is used to enhance the Raman signal by extending the laser-gas interaction length.

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We report a novel, to the best of our knowledge, and simple technique to lock a 642 nm multi-quantum well diode laser to an external linear power buildup cavity by directly feeding the cavity reflected light back to the diode laser for enhancement of gas Raman signals. The dominance of the resonant light field in the locking process is achieved by reducing the reflectivity of the cavity input mirror and thus making the intensity of the directly reflected light weaker than that of the resonant light. Compared with traditional techniques, stable power buildup in the fundamental transverse mode TEM is guaranteed without any additional optical elements or complex optical arrangements.

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Acetone is an essential indicator for determining the aging of transformer insulation. Rapid, sensitive, and accurate quantification of acetone in transformer oil is highly significant in assessing the aging of oil-paper insulation systems. In this study, silver nanowires modified with small zinc oxide nanoparticles (ZnO NPs@Ag NWs) were excellent surface-enhanced Raman scattering (SERS) substrates and efficiently and sensitively detected acetone in transformer oil.

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Single-atom catalysts offer maximal atom utilization efficiencies and high-electronegativity heteroatoms play a crucial role in coordinating reactive single metal atoms to prevent agglomeration. However, these strong coordination bonds withdraw electron density for coordinated metal atoms and consequently affect their catalytic activity. Herein we reveal the high loading (11.

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We report a dense-pattern multi-pass cavity (MPC) based on four spherical mirrors placed in a Z-shaped cavity configuration for improving the Raman signals from gases. The folding structure of the cavity causes dense patterns of spots, and at least 420 beams are reflected in the cavity. Raman spectra of ambient air, methane, and ethylene are recorded to demonstrate the performance of our apparatus.

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Article Synopsis
  • Accurately assessing the aging of oil paper insulation in power transformers is crucial for ensuring their safe operation.
  • A novel detection method using flower-like silver nanoparticles modified with carbon nanotubes (CNTs@Ag-F-AgNPs) was developed for highly sensitive detection of dissolved furfural in transformer oil.
  • The method demonstrated a low detection limit of 2.25 mg/L for furfural, with excellent reproducibility and potential for in-situ monitoring of transformer oil quality.
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The vibration spectroscopy (Raman and infrared) of widely concerned molecules in sulfur corrosion phenomenon (Dibenzyl Disulfide, Dibenzyl Sulphide, and Bibenzyl) is detailedly analyzed based on density functional theory and experimental measurement. The dominant conformations of these molecules are determined according to Boltzmann distribution in relative Gibbs free energy. Additionally, noncovalent interaction analysis is conducted to indicate intramolecular interaction.

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To assess the aging of oil-paper insulation, an accelerated aging experiment is executed. Raman spectroscopy, a nondestructive detection method with access to component identification and fault diagnosis, is used to analyze the aging of oil-paper insulation. Raman feature of oil-paper insulation aging with a close relationship with the degree of polymerization is obtained based on the concept of quadratic mutual information.

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We demonstrate the practicability of cavity-enhanced Raman spectroscopy (CERS) with a folded multipass cavity as a unique tool for the detection of hazardous gases in the atmosphere. A four-mirror Z-sharped multipass cavity results in a greatly extended laser-gas interaction length to improve the Raman signal intensity of gases. For Raman intensity maximization, the optimal number of intracavity beams of a single reflection cycle is calculated and then the cavity parameters are designed.

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An innovative fiber-enhanced Raman gas sensing system with a hollow-core anti-resonant fiber is introduced. Two iris diaphragms are implemented for spatial filtering, and a reflecting mirror is attached to one fiber end that provides a highly improved Raman signal enhancement over 2.9 times than the typical bare fiber system.

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