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Oversampling is a popular yet useful method to fulfill the binary classification of imbalanced data, however many existing results of oversampling are very likely to generate redundant/unsafe/noise samples due primarily to the inadequate consideration of the data distribution. To address this issue, we propose a novel oversampling approach, namely Switching Synthesizing-Incorporated and Cluster-Based Synthetic Oversampling (SSI-CBSO). The core idea of SSI-CBSO is four-fold: (1) noise samples are removed by using K nearest neighbor strategy and Fuzzy C-Means clustering is adopted for the filtered data in the minority class; (2) the number of samples that need to be synthesized is adaptively assigned to each cluster concerning the inter-class distance and the intra-cluster similarity; (3) to better reflect the data distribution, a new method in terms of the concept of the hypersphere is put forward to measure the cluster density in a high dimensional; and (4) a new principle based on the Mahalanobis distance is provided for a better selection of the target sample. Then, a switching synthesizing strategy is established to guarantee the safety of the synthesized samples. Finally, experiments on 13 binary imbalanced data sets by using five evaluation metrics with four classifiers verify that our proposed SSI-CBSO approach can obtain desirable results. [ABSTRACT FROM AUTHOR]

• Cr and Mn improved the low-temperature catalytic activity and SO 2 resistance. • Cr and Mn doping improved the rate of the catalytic reaction. • The reaction followed the Eley–Rideal and Langmuir–Hinshelwood mechanisms. • The catalyst significantly inhibited the accumulation of bisulfate or sulfate. A series of Cr α Mn β CeTiO x catalysts were prepared using one-pot precipitation method and evaluated for the selective catalytic reduction (SCR) of NO with ammonia. Among the catalysts prepared, the Cr 0.006 Mn 0.05 CeTiO x catalyst exhibited the highest low-temperature activity and widest activity window (＞90% NO conversion at 160–425 °C) as well as outstanding sulfur resistance. The catalysts were characterized using XRD, NH 3 /NO/SO 2 + O 2 -TPD, XPS, in situ DRIFT, and so on. The amorphous Cr 0.006 Mn 0.05 CeTiO x catalyst had a larger specific surface area, high ammonia adsorption and strong acidity, resulting in an improved catalytic activity. A high ratio of surface adsorption oxygen and Ce3+ promoted the formation of NO 2 , a key intermediate gas in the fast SCR reaction. Furthermore, in situ DRIFT showed that the SCR reaction followed the Eley Rideal and Langmuir Hinshelwood mechanisms. Moreover, the synergetic effect of Cr and Mn inhibited the accumulation of hydrogen sulfate or sulfate considerably. [ABSTRACT FROM AUTHOR]

Recently, with the ongoing development of the express industry, the consumption of waste plastic express bags has been increasing year by year, which has brought considerable pressure on municipal waste management. At the same time, in China, where coal is the main energy resource, the upgrading of low-rank coal is a more reliable and prospective way. An effective method for waste treatment and resource upgrading by synergistic co-liquefaction of waste plastic express bags and low-rank coal in a supercritical water-ethanol system has been developed. The effects of different experimental factors (temperature, residence time, plastic-coal ratio, water-ethanol ratio) on the conversion ratio and synergistic effect of co-liquefaction were investigated. The results showed that elevated temperature, lower water-ethanol ratio as well as suitable residence time, and plastic-coal ratio of 1:1 were conducive to the conversion ratio. Temperature ≥375 °C and suitable plastic-coal ratio (1:1) had a significant positive synergistic effect on the conversion ratio, whereas the other conditions exhibited no or negative synergistic effect on the conversion ratio. The maximum conversion ratio and positive synergistic efficiency were 85.11% and 12.25% at 425 °C, 60 min, water-ethanol ratio of 1:1, and plastic-coal ratio of 1:1, respectively. It was observed after FT-IR and elemental analysis based on the solid residue that the oxygen-containing functional groups in the residue disappeared, the oxygen content decreased, the carbon content increased, and the higher heating value (HHV) increased significantly, and the residue could be further used (such as gasification or pyrolysis) without the need for landfill. The GC-MS results of the oil products suggested that the oil products contained high content of hydrocarbons and phenols, as well as esters, alcohols, and other compounds. The hydrocarbons and phenols mainly derived from the decomposition of long chains in plastics and the decomposition of aromatic structures in coal, and the hydrocarbon and phenolic contents produced at 400 °C were 27.74% and 32.62%, respectively. Thus, the oil product can be used further as a chemical raw material. It cannot be ignored that the ethanol medium after reaction can also be further recycled by rotary evaporation. The synergistic co-liquefaction of waste plastic express bags and low-rank coal based on supercritical water-ethanol system is a promising method for waste treatment and resource upgrading. [Display omitted] • A synergistic co-liquefaction for waste express bags and low-rank coal was developed. • Ethanol can improve the synergistic efficiency of co-liquefaction. • The maximum conversion ratio of co-liquefaction reached 85.11% at 425 °C, 60 min. • Oil products from co-liquefaction contained hydrocarbons and phenolic compounds. [ABSTRACT FROM AUTHOR]

[Display omitted] • Gained FeSiCr-based SMCs with a CeO 2 ·SiO 2 composite layer by selective oxidation between substrate and CeO 2 insulation layer. • The CeO 2 insulation layer promotes selective oxidation of Si in substrate during sintering in water vapor environment. • CeO 2 ·SiO 2 composite insulation layer demonstrated a 22.9% reduction in core loss than using the CeO 2 insulating layer alone. • CeO 2 ·SiO 2 composite insulation layer mitigated core loss while maintaining high magnetic conductivity in FeSiCr-based SMCs. This study introduces an approach to fabricating soft magnetic composites (SMCs) that effectively address core loss while maintaining high magnetic conductivity. During the sintering process in a water vapor environment, the CeO 2 insulation layer facilitates the selective oxidation of Si while simultaneously impeding the outward diffusion of Fe and Cr. Consequently, a CeO 2 ·SiO 2 composite insulation layer forms within the FeSiCr-based SMCs. The FeSiCr-based SMCs with the CeO 2 ·SiO 2 composite insulation layer achieve a saturation magnetization of 153.1 emu/g, which is 10.9% lower than that of FeSi 3.7 Cr 4.5 compacts, and exhibits a deterioration rate lower than previously reported values. Moreover, the permeability of the FeSiCr-based SMCs remains highly stable, demonstrating outstanding insulation characteristics. The total core loss and core loss separation results further corroborate that incorporating a CeO 2 ·SiO 2 composite insulation layer leads to a more pronounced reduction in interparticle eddy current loss than using a CeO 2 insulating layer alone. This performance enhancement can be attributed to the selective oxidation of a rare metal oxide insulation layer on a ferromagnetic metal particle substrate, a technique applied to SMCs for the first time. These findings hold significant implications for the design of high-performance SMCs in miniaturized and lightweight electromagnetic devices. [ABSTRACT FROM AUTHOR]

Residual stresses evidently affect the strength, fatigue property and machining deformation of the mechanical components. Therefore, stress relief processes are extensively applied in the manufacturing to enhance the mechanical properties of products. In this study, seven 7075 aluminium alloy specimens are treated by thermal- vibratory stress relief (TVSR), thermal stress relief (TSR), and vibratory stress relief (VSR). Finite element (FE) models considering the stress relaxation effects and transient periodic vibration loads are proposed to simulate the TVSR, TSR and VSR process. The residual stresses before and after the processes are measured and compared, and the effectiveness of the FE models is validated. Scanning electron microscope (SEM) and transmission electron microscope (TEM) are used to observe the microstructure and crystal dislocation, respectively. Results show that TVSR can evidently reduce the residual stress in aluminium alloy, and the stress relief rate of TVSR for the peak stress are 20.43% and 38.56% higher than that of TSR and VSR, respectively. It also found that TVSR has no obvious influence on the grain size, but evidently increase the dislocation density. Eventually, the stress relief mechanism of TVSR is analyzed and summarized. Unlabelled Image • The influences of on the residual stress relief, micro structure, and dislocation density of 7075 aluminium alloy are investigated. • FE models are proposed to simulate the TVSR, TSR and VSR process. • The stress relief rate of TVSR for the peak stress are 20.43% and 38.56% higher than that of TSR and VSR. • TVSR promotes the growth and entanglement of dislocations in the crystals. [ABSTRACT FROM AUTHOR]