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Background: Fault diagnosis methods based on deep learning have achieved remarkable results. However, sample imbalance and constructing an appropriate model are still key issues to be addressed. Purpose: In this work, we present a novel diagnostic model design framework named Dynamic Adaptive Structural Parameter Optimization (Dy-ASPO). The proposed design framework integrates input information and training process information to dynamically and adaptively select the optimal structure for the model. Methods: We adopt a new convolution termed Inception Convolution (IC-Conv), which is based on statistical optimization to select the optimal expansion mode in the supernet in a low-cost manner. Second, our proposal adaptively finds operations that contribute most to the loss in the network and applies Dynamic diverse branch blocks (Dydbb) to enhance their representational capacity. Then, we introduce batch-Attention, which is applied to the batch dimension to implicitly explore sample relationships during training. Thus, the model achieves the collaboration of different samples. Results: Two case studies are constructed to test the performance of the proposed method on different bearing failure data under different scale sample distributions and noise combinations. Comparing the accuracy of various methods, the F1-score, as well as the confusion matrix and T-SNE plot of the output of different datasets, reflects the efficiency and practicality of the proposed method. Conclusion: The experimental results demonstrate that the Dy-ASPO operates the internal parameters and structure of the optimization model in a fast and low-cost manner, and solves the issue of the scarcity of samples in an extremely simple way.

Skin wounds are usually accompanied by bacterial infections and inflammations, leading to delayed wound healing, which remain a great challenge in clinical treatment. Therefore, it is of great significance to develop wound dressings that inhibit bacterial infections to accelerate wound healing. Herein, we reported the fabrication of inclusion complex (a β-cyclodextrin covalent organic framework loaded with enrofloxacin and flunixin meglumine)-incorporated electrospun thermoplastic polyurethane fibers (named ENR-FM-COF-TPU) via electrospinning. The obtained ENR-FM-COF-TPU fibrous membrane exhibited excellent physicochemical and biological properties such as uniform and stable morphology, proper hydrophobicity, good water uptake capacity, and admirable biocompatibility, which showed perfect behavior as a wound dressing. In addition, the ENR-FM-COF-TPU membrane achieved a sustained drug release of enrofloxacin and flunixin meglumine and displayed powerful antibacterial activity against Staphylococcus aureusand Escherichia coliwith 99% inhibitory efficiency for 50 h. More importantly, the wound healing therapy effect was investigated using a full-thickness skin defect model of mice. It suggested that the ENR-FM-COF-TPU membrane could significantly accelerate and enhance wound healing through downregulating inflammatory cytokines (IL-1β and TNF-α) and increasing the expression of growth factors (VEGF and EGF). Due to its excellent properties, the ENR-FM-COF-TPU membrane may have promising potential in wound healing applications.

CoFe alloy nanoparticles with ultra-high-density are exsolved on the (PrBa)0.95(Fe0.8Co0.1Nb0.1)2O5+δ(PBFCN0.1) surface under reducing atmosphere, achieving high performance when H2or C2H6is used as fuel.

The invasion of aquifers into fractured gas reservoirs with edge water aquifers leads to rapid water production in gas wells, which reduces their gas production. Natural fractures accelerate this process. Traditional reservoir engineering methods cannot accurately describe the water influx, and it is difficult to quantitatively characterize the influence of aquifer energy and fracture development on production, which prevents aquifer intrusion from being effectively addressed. We divided the water influx of edge water aquifers in fractured gas reservoirs into three patterns: tongue-like intrusion in the matrix, tongue-like intrusion in fractures, and channel intrusion in fractures. Detailed numerical modeling of the water influx was performed using an embedded discrete fracture model (EDFM) to predict gas production. Because the strength of the aquifer and the conductivity of natural fractures have different effects on water influx, the effects of aquifers and natural fractures on the gas production of wells under the three water influx modes were studied. The results show that tongue-like intrusions lead to a stronger initial gas production of gas wells, which then become weaker after the wells are flooded, and the intrusions such as channeling in fractures cause the gas well to be flooded quickly. However, not all water influxes are unfavorable for gas production. Aquifers with water energy similar to gas formation and natural fractures with weak conductivity can improve the production of gas wells.

•Pin fins are introduced into mini-channel cold plate for battery thermal management.•Efficiency index is used as an overall evaluation of cooling performance.•The effects of arrangement and layout of pin fins on the performance is studied.•Mini-channel cold plates with pin fins achieve better efficiency index.

Spherical hollow zinc oxide (ZnO) nanoparticles have been successfully synthesized by templating micelles of poly(styrene-b-acrylic acid-b-ethylene oxide) (PS-b-PAA-b-PEO). This polymer forms a micelle with a PS core, a PAA shell, and a PEO corona in aqueous solutions. Zinc chloride (ZnCl2) and sodium hydrogen carbonate (NaHCO3) were used as precursors of ZnO. In the synthesis, the PS core acts as a template for cavities of the hollow particles, the PAA shell is beneficial for arresting zinc ions for further mineralizing, and the PEG corona stabilizes the zinc hydrogen carbonate (Zn(HCO3)2)/polymer nanocomposite to prevent secondary aggregate formation. Hollow ZnO nanoparticles were obtained after the calcination of the separated (Zn(HCO3)2)/polymer nanocomposite at 500 °C for 4 h. The hollow ZnO nanoparticles were characterized by various techniques including transmission electron microscopy and X-ray diffraction analysis. The hollow ZnO particles have a spherical shape, a narrowly distributed size of 24.7 ± 1.3 nm, and a shell thickness of 6.9 ± 0.7 nm. Compared with other methods, the present method gives hollow ZnO nanoparticles with smaller size (ca. 25 nm), narrow size distribution, controlled shape, and robust shell. This result strongly demonstrates the advantages of the present synthesis route.

Abstract: A novel hyperbranched multiarm copolymer of HBPO-star-PDEAEMA with a hydrophobic poly(3-ethyl-3-(hydroxymethyl) oxetane) (HBPO) core and many cationic poly(2-(N,N-diethylamino)ethyl methacrylate) (PDEAEMA) arms has been synthesized through an atom transfer radical polymerization (ATRP) method, and been applied to spontaneously reduce and stabilize gold nanoparticles (AuNPs) in water without other additional agents. The size of the nanoparticles could be effectively controlled at about 4 nm, and the nanoparticles are extremely stable in solution without aggregation even for one year. It was found that solution pH and the molar ratio of N/Au have certain effects on the size and stability of AuNPs. This work provides a simple method for the synthesis of uniform and highly stable AuNPs.

Copper oxide (CuO) hollow nanospheres have been fabricated by using a micelle of poly(styrene-block-acrylic acid-block-ethylene oxide) (PS-b-PAA-b-PEG) as a template. The TEM image reveals that the diameter of the synthesized nanosphere is 40 ± 1 nm with a shell thickness 10 ± 1 nm. The CuO nanosphere electrode delivers high capacity at 350 mA h g−1after 30 cycles, which is associated to the hollow void space coupled with the nanosized shell domain that facilitates fast lithium diffusion.

La0.8Sr0.2Mn0.5Co0.5O3(LSMC) perovskite anchored with RuOx(LSMC-Ru) is fabricated as a new bifunctional electrocatalyst, with low dosage (2.43 wt %) and high utilization of noble metal Ru. The LSMC-Ru exhibits outstanding bifunctional activity with a low potential gap of 0.72 V between the oxygen evolution reaction (OER) potential at 10 mA cm–2and the oxygen reduction reaction (ORR) half-wave potential. The strong electronic interaction between RuOxand LSMC is confirmed by both experiments and theoretical calculations. Consequently, the electron-rich Mn centers promote ORR, while the electron-deficient Ru centers facilitate OER. A Zn-air battery using the LSMC-Ru air electrode delivers a peak power density of 159 mW cm–2and a low charge–discharge potential gap of 0.58 V at 2 mA cm–2. The high round-trip energy efficiency of 60.6% is retained after 300 cycles. This strategy of anchoring a low dosage noble metal catalyst to perovskite can be extended to other systems of noble metal-non-noble metal composite electrocatalysts to achieve both competitive performance and low cost.

Hollow calcium tungstate (CaWO4) nanospheres with well-controlled shape and size have been successfully synthesized for the first time by templating micelles of poly(styrene-b-acrylic acid-b-ethylene oxide) (PS-b-PAA-b-PEO). This polymer forms a micelle with a PS core, a PAA shell, and a PEO corona in aqueous solutions. Calcium chloride (CaCl2) and sodium tungstate (Na2WO4) were used as precursors of CaWO4. In the synthesis, the PS core acts as a template for cavities of the hollow particles, the PAA shell is beneficial for arresting calcium ions for further mineralizing, and the PEO corona stabilizes the CaWO4-polymer nanocomposite to prevent secondary aggregate formation. The hollow CaWO4nanoparticles have a spherical shape with an outer diameter narrowly distributed at 22.7 ± 1.0 nm and a shell thickness at 6.7 ± 0.4 nm.