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In the process of jet weaving, airflow plays a primary role by carrying the weft yarns and interlacing them with the warp yarns to form the fabric. The vortex characteristics within the weft insertion channel of an air-jet loom directly affect the motion of the weft yarns, thus impacting the quality of the fabric. In this study, the large eddy simulation (LES) method was employed, and the Omega vortex identification criterion was used to analyze the vortex characteristics within the profile reed channel. The effects of different positions of relay nozzles, nozzle spacing, and reed gap ratio on the airflow characteristics were investigated. Additionally, the vortex volume ratio ( W ) and velocity fluctuation rate ( S ) were introduced as indicators to measure the proportion of vortices and the turbulence intensity of the airflow field. The numerical results indicated that the introduction of relay nozzles significantly reduced the intensity of airflow vortices and the proportion of vortices within the profile reed channel. When the inlet pressures of the main and relay nozzles were fixed, the minimum values of W and S were observed when the first relay nozzle was located at 105 mm, the nozzle spacing was 65 mm, and the gap ratio was 1:2. The findings of this study provide theoretical guidance for further improving the airflow characteristics within the profile reed channel of an air-jet looms. [ABSTRACT FROM AUTHOR]

In the field of flow field reconstruction, traditional deep learning models predominantly rely on standard convolutions, but their predictive accuracy remains limited. To address this issue, we explore the potential of E(2)-equivariant convolutions to enhance the predictive accuracy of deep learning models for fast flow field prediction. Unlike conventional convolutions, E(2)-equivariant convolutions offer a richer representation capability by better capturing geometric and structural information. Our neural network integrates an attention mechanism that leverages the signed distance function (SDF) to encode geometric details and an indicator matrix to incorporate boundary conditions. The model predicts velocity and pressure fields as outputs. We conducted experiments specifically targeting non-uniform steady laminar flows, and the results show a 16.1% reduction in overall error compared to models based on traditional convolutions while maintaining high efficiency. These findings indicate that E(2)-equivariant convolution, coupled with an attention mechanism, significantly improves flow field prediction by focusing on critical information and better representing complex geometries. [ABSTRACT FROM AUTHOR]

Plasma catalytic CO2 hydrogenation to methanol over MnOx/ZrO2 catalyst was investigated in this work. A boosted methanol yield of 4.6 mg/h was obtained over MnOx/ZrO2 catalyst, while it was only 0.0 and 0.7 mg/h for ZrO2 and MnOx catalyst, respectively. The interaction between MnOx and ZrO2 was responsible for the enhanced methanol yield. It resulted in sufficient oxygen vacancy. The in situ DRIFT spectra was conducted to reveal the plasma catalytic CO2 hydrogenation to methanol reaction mechanism and the key intermediates of HCOO and CH3O species were determined. The sufficient oxygen vacancy promoted the formation of the key intermediates, especially the CH3O species. [ABSTRACT FROM AUTHOR]

An unclassical structure of {Ru(C6H6)}‐based polyoxometalate, Cs6H4[Te2Mo12O46{Ru(C6H6)}] ⋅ 16.5H2O (1), has been successfully constructed from {Te2Mo12O46}‐type heteropolymolybdate and {Ru(C6H6)} group, which structure type was discovered for the first time. Compound 1 not only possesses strong light‐harvesting ability, but also exhibits high carrier separation efficiency and lower charge transfer resistance. Under visible light irradiation, compound 1 displayed excellent catalytic activity and circularity in the conversion of benzyl alcohol to benzaldehyde (yield=94 %; turnover number=500; turnover frequency=20.8 h−1). Finally, the electron paramagnetic resonance measurement and energy level matching analysis provide theoretical basis for the derivation of the reaction mechanism. [ABSTRACT FROM AUTHOR]

To interpret why rotor-spun yarns have fewer straight fibers, numerical simulations are performed to explore the fiber dynamics and morphological evolution during its conveyance in a rotor spinning unit by the airstream. Results show that the fiber experiences a sharp speed increase after reaching the shear boundary layer of the rotating wall. The sharp speed increase ends when the fiber arrives at the rotor groove where its morphology and speed barely change. The fiber straightness undergoes a process of first decreasing and then increasing during the conveyance and the worst fiber straightness is obtained halfway during the fiber's sliding process. Compared with the fiber transport channel (FTC) angle, the rotor speed and the suction pressure play a more important role in affecting the fiber dynamics and morphological evolution. Fiber can be more efficiently conveyed as the rotor speed increases or/and the suction pressure decreases, and its straightness varies non-monotonically with these two parameters. Too low or too high rotor speed and suction pressure could result in a decrease in the fiber straightness, and the straightest fiber is obtained at a medium rotor speed of 80,000 rpm and a medium suction pressure of −8000 Pa for our considered system parameters. [ABSTRACT FROM AUTHOR]

Oxygenates production from the partial oxidation of liquid fuel is required for a cleaner combustion. The effect of Mn/Fe ratio was investigated to improve the oxygenates formation via plasma catalytic n-C5H12 partial oxidation over FeMn/Al2O3 catalyst. The oxygenates selectivities exhibited a volcano shape with the Mn/Fe ratio and the highest value of 69% was obtained at Mn/Fe ratio of 7/3. The oxygenates selectivities were dominated by both the acidity and active oxygen species of catalyst, which could be tuned by Mn/Fe ratio. A close relationship between oxygenates selectivities, acidity, and active oxygen species of catalyst was established. The higher the active oxygen species content and the lower the acidity, the higher the oxygenates selectivities. [ABSTRACT FROM AUTHOR]

A heteropolytungstate cluster [{Ru2O(bpy)2}2{Bi2W32O110}]10− (bpy = C10H8N2) was incorporated into a 2 : 1 type layered porous framework by interweaving the Na+ bridged cluster chains through the hydrogen bonding ability of the bpy ligands. It features multiple pore channels rich in hydrogen-bond network, contributing high conductivities > 10−2 S cm−1 at 298–358 K and 85% RH. [ABSTRACT FROM AUTHOR]

Wear at the inner surface of the rotor cup by granular impurities could adversely affect the slip of fibers and increase yarns' hairiness. Therefore, understanding the mechanism of wear formation due to the moving granular impurities and the wear characteristics at the inner surface of the rotor cup is of great significance for the improvement of yarn quality. This paper numerically explores the mapping relationship between the motion characteristics of particles (i.e. spherical impurities) and the wear characteristics of the rotor cup via the combination of computational fluid dynamics (CFD) and the discrete element method (DEM). The simulation results are first validated against the experimentally obtained microscopic view of the surface of the discarded rotor cup. After that, the wear characteristics of the rotor cup under different rotating speeds and angles of the transfer channel are analyzed. The results show that the most serious cutting and impact wear is found at the rotor groove, followed by the first collision position of the slip surface. The cutting and impact wear in the rotor groove are positively correlated with the rotating speed, while are not affected by the angle of the transfer channel. The cutting and impact wear at the first collision position of the slip surface are negatively correlated with the rotating speed and the angle of the transfer channel. However, the impact and cutting wear at the first collision position is no longer affected significantly by the rotating speed when it is above 90000 rpm. Increasing the rotating speed and the angle of the transfer channel is found to reduce the second wear area on the slip surface of the rotor cup. [ABSTRACT FROM AUTHOR]