The introduction of high-valence state elements and highly active species is promisingly desired to design superior electrocatalysts for water electrolysis. Exploring scalable synthetic strategies necessary an in-depth understanding the mechanism improving electrocatalytic performance. But it remains challenging. Herein, several through element doping are prepared. obtained Mo-CoP

ICP-MS is becoming a competitive technique for measurement of plutonium isotopes. Besides the abundance sensitivity (tailing 238U to m/z = 239 and 240), isobaric polyatomic ions interferences (e.g., 238U1H+) are most critical challenges determination low-level in high uranium samples. This work presents new method solve this problem using with two tandem quadrupole separators dynamic collision/reaction cell combined chemical separation. The interference hydrides (238U1H+ 238U1H2+) was...

It is critical to design bifunctional nonprecious electrocatalysts with low costs and high efficiency for hydrogen production. Conventional electrocatalysts, on the other hand, frequently exhibit significant overpotential slow transfer kinetics in both oxygen evolution reactions (HER OER). Cation doping engineering believed be a suitable way deal this problem. To accomplish effective water electrolysis, we use simple vanadium ion strategy prepare 0.5V-NiCoP. In acidic alkaline environments,...

The fiber optic interferometer, an instrument for partial discharge (PD) acoustic wave detection, is currently receiving much attention. Due to the high sensitivity, dual-arm interferometers have been used in field of detection a long time. However, long-distance guided structure interferometer prone coupling environmental noise, and there are difficulties matching optical path difference which generate interference. This paper elaborates on two types single-arm interferometric technology...

This study addresses the challenges of electromagnetic interference and unstable signal transmission encountered by traditional sensors in detecting partial discharge (PD) within stator slots large motors. A novel Extrinsic Fabry-Perot Interferometer (EFPI) sensor with a vibration-coupling air gap was designed to enhance narrowband resonant detection sensitivity for PD ultrasonic signals optimizing diaphragm structure coupling interface. The features quartz thickness 20 μM, an effective...

Aiming at the issues of low sensitivity and poor resistance to temperature vibration interference in traditional optical fiber current transformers, as well structural complexity magnetostrictive material-coupled sensors, this paper integrates a high-sensitivity electrostrictive piezoelectric ceramic sensor with an FBG-FP cascaded fiber-optic sensor. This coupling significantly optimizes structure. By employing orthogonal intensity demodulation enhance detection sensitivity, adopting...

Currently, in the modern power industry, it is still a great challenge to achieve high sensitivity and uninterrupted-online measurement of large current on voltage gridlines. At present, fiber grating sensors based giant magnetostrictive material used industry currents grid lines better method, but this sensor relatively low, therefore, key improve sensor. Here we show sensitivity-enhanced (in following, simply referred as sensor) that able by means pressurizing material. Sampling frequency...

The demodulation method of optical fiber sensors utilized in power transformer partial discharge (PD) detection is insufficient for engineering applications. We design a distributed feedback laser (DFB-FL) PD system with an asymmetric 3 × coupler and propose ultra-high signal-to-noise ratio (SNR) scheme by eliminating the main factors that affect traditional using coupler. results reveal proposed free from asymmetry issues, average SNR 38.30 dB, which much higher than widely used...

The insulation of power equipment can be effectively assessed by analyzing the acoustic signals originated from partial discharges (PD). Fabry-Perot (F-P) sensors are capable detecting PD signals. Although frequency bandwidth an F-P sensor is mainly referred to conventional piezoelectric transducer (PZT) sensor, it still doubtful identify a suitable for fiber in detection To achieve distribution emission investigated, and extrinsic designed detect generated PD. with different intrinsic...

In this study, we synthesized numerous Co–Mo–S nanosheet networks as electrode materials by a two-step hydrothermal strategy. It delivers specific capacity of 510 C g −1 at 1 A .

The traditional fiber optic acoustic emission (AE) sensor, used to detect the partial discharge (PD) in liquid-solid composite dielectric such as oil-immersed transformers, is not satisfactory engineering applications due limitation of sensitivity and sensor size. This work proposes that distributed feedback laser (DFB-FL), benefiting from its tiny size ultra-high sensitivity, a better choice for PD AE detection. We build detection system using erbium-ytterbium co-doped (Er-Yb-co-doped)...

Abstract The 2 × couplers, as a demodulation core of the fibre optic sensing system, have been extensively employed in sensors for partial discharge (PD) detection power equipment. However, unstable sensitivity and low signal‐to‐noise ratio (SNR) such system are still unsatisfactory engineering. This work uses distributed feedback laser sensor employs common asymmetric 3 coupler instead to design PD system. Then, we propose new method acoustic emission signals based on Naval Postgraduate...

This paper proposes control methods to achieve accurate active and reactive power sharing of parallel multi-inverters in proportion their capacities. Firstly, according physical properties inverters' output power, the interaction mechanism between circulating-current load-sharing is elaborated. Conditions for a strategy result specified minimum are discussed based on assumption that transmission lines inductive. Limited effectiveness traditional droop deeply analysed. An improved proposed...

Active fiber optic acoustic emission (AE) sensors cause external optical feedback (EOF) in engineering applications, resulting performance loss when used for long-distance partial discharge detection power transformers. This work employs a distributed laser (DFB-FL) as sensor to construct system. Furthermore, two schemes that improve the of DFB-FL are proposed by Suppressing EOF (S-EOF) and Introducing (I-EOF). Then, tests an 80 kVA transformer validate both can implement detection....