A range of nitro compounds are smoothly reduced to their corresponding oximes under the synergistic effects visible light irradiation, Ru(bpy)3Cl2 photocatalyst, Hünig's base, Mg(ClO4)2 activation, and MeCN solvent. This remarkably mild environmentally benign protocol, when orchestrated with classical Beckmann rearrangement, enables such high-value industrial feedstock as caprolactam be readily accessed from simple precursor nitrocyclohexane.

The organic piezoelectric polymer polyvinylidene fluoride (PVDF) has attracted extensive research because of its excellent flexibility and mechanical energy-harvesting properties. Here, the electrospinning technique was taken to fabricate synthesized fiber membranes a PVDF/cellulose acetate (CA) composite. obtained PVDF/CA electrospun (EFMs) were employed prepare flexible nanogenerator. XRD FTIR spectroscopy revealed enhancement behavior due an increase in β-phase EFMs compared with cast...

A series of enamines were photocatalytically cleaved to produce amide products under simple visible-light irradiation from a 45 W household light bulb. Mechanistically, the reactions appear involve photosensitized formation singlet oxygen intermediate and subsequent [2+2] cycloaddition event.

This study investigated the influence of main metal materials transformers on oil-paper insulation performance. Ten types insulating specimens were subjected to accelerated thermal aging at 120°C. Some parameters, including oil acid number, furfural content and degree polymerization (DP) paper, measured compared. At same time, we conducted frequency domain spectroscopy, X-ray diffraction, scanning electron microscopy energy dispersive spectrometry paper. The following conclusions drawn:...

In the long-term working state, stains such as dust, oil, and charged particles in environment are prone to deposit on surface of power equipment, which has great security risks. To achieve anti-stain performance, fluorocarbon composite coating with a low energy was prepared studied. this paper, SiO2 nanoparticles were used inorganic fillers resin substrate form coatings. By adjusting optimizing ratio organic resins, coatings different static contact angles constructed. The optimum angle 151...

The performance of oil-impregnated paper significantly affects the safety and reliability transformers. Previous studies on water reducing breakdown strength have been mainly due to increasing charge carriers conductivity. However, influence cellulose crystal structure is still not clear; in particular, its role remains ambiguous. In this study, AC vegetable mineral with different moisture contents were investigated. results show that content, crystallinity size increases linearly, while...

Prediction of gas emission has received much attention on the security production coal mining during last decade. Gas is a random time series and abnormal values can cause some dangerous events. We analyze these data develop an online LS-SVR algorithm named TOLS-SVR based data. Time from are converted into set vectors using theory series. The optimal embedding dimension determined through cross validation technique. Experimental results demonstrate good performance efficiency proposed...

Recently, a large amount of power transformer dielectric failures caused by the copper sulfide (Cu <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> S) contaminant are reported, which is semi-conductive black solid material produced reaction DBDS additive and under certain temperatures. Irgamet 39 used as metal passivator in oil that can delay corrosion process laboratory investigations, forms protective layer on surface to prevent harmful...

Exploration of beneficial catalyst–substrate interactions in the classical Sharpless asymmetric dihydroxylations (SAD) led to identification allylic <italic>N</italic>,<italic>N</italic>-dimethylaminobenzoate as an efficient auxiliary for inducing high levels enantioselectivity 1,1-disubstituted aliphatic alkenes.

In order to explore a non-destructive method for measuring the polymerization degree (DP) of paper insulation in transformer, new that based on optical properties free fiber particles transformer oil was studied. The chromatic dispersion images fibers with different aging were obtained by polarizing microscope, and eigenvalues (r, b, Mahalanobis distance) extracted RGB (red, blue, green) tricolor analysis method. Then, correlation between three DP simulated respectively. results showed color...

The removal of dibenzyl disulfide (DBDS) from transformer oils is vital to the sustainable operation transformers. Here, Ag/γ-Al2O3 samples were prepared by a planetary mixer-assisted impregnation method and characterized. effect adsorption time temperature on equilibrium DBDS onto was discussed. kinetics isotherms studied. desorption activation energy also estimated through temperature-programmed (TPD) experiments. Results indicated that capacities increased quickly within first 3 h,...

Chromatic dispersion characteristics are key parameters for high-speed fibre-optic networks, and an accurate knowledge of first- second-order dispersions is essential new special linear nonlinear optical devices. In this paper, we propose a multi-section interference theory the analysis spectral domain fringe patterns. Based on theory, report novel direct measurement by determining second symmetric interferometric pattern. This was performed using Mach–Zehnder interferometer, broadband LED...

The aging tests of nitrile rubber were carried on in transformer oil, and under compression oil.The effects stress the thermal behaviors studied by mechanical property measurements.The variations physical properties during ageing process analyzed compared.The change elongation at break oil was lower than that lifetime NBR 25˚C predicted compared with set or as evaluation indexes, 50% critical value.

Vehicle axle structural design and optimization is an important part of the vehicle development process. Its strength directly related to safe under impact. The should consider integrity, achieve same database analysis data, parameters model ATV's set up based on seamless integration technique all module Pro/E platform, use FEA analyze stress deformation axles,comparative with other models finally finish design.

The kinematics of 3-PRS parallel mechanisms (PMs), an important category 2R1T PMs, is very for the motion control and error compensation PMs. In order to produce a spindle head that could meet requirements various machining accuracy levels, definite analysis PMs par should be taken with caution firstly. Here, mathematical models two different branch chain arrangements were established using Euler angle. kinematic equations obtained by establishing closed-vector loop equation according...

In a high-moisture environment where dust and coastal saltwater are prevalent, the stability of power equipment can be adversely affected. This issue result in downtime, particularly for transformers, severely disrupting continuous operation DC transmission systems. To address this challenge, superhydrophobic modified fluorosilicone coating was developed, incorporating anti-stain properties. tackle comprehensively, an orthogonal experiment conducted, involving six factors three levels. The...

Timely and effective identification of transformer aging is great importance to the safety stability power system. In this paper, a method for diagnosing oil-paper insulation based on ultrasonic time-frequency characteristics proposed. First, prepared aged oil samples were subjected testing. Then, Pearson correlation coefficient was used screen 8 features that strongly correlated with oilpaper insulation. Finally, diagnostic model established above combined radial basis function neural...