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The new-generation polyimide films with simultaneously outstanding thermal stability and low coefficient of linear thermal expansion (CTE) are urgently needed. Herein, coordination bonds were employed to improve polyimide films' heat resistance and dimensional stability. Polyimide-Cu complex films were fabricated by incorporating α-diimide units (bidentate ligands) into the BPDA-ODA (the structure of commercially available Upilex-R® polyimide films) backbones. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and Energy dispersive X-ray mapping results showed that the coordination interactions occur between α-diimide and copper ions. Wide-angle X-ray diffraction (WAXD) and two-dimensional small-angle X-ray scattering (SAXS) spectra demonstrated that Cu-α-diimide coordination structures introduced in intermolecular chains leading polyimide films transformed from a semi-crystalline state to amorphous state, and inhibited the long-period formation structures. The plateau modulus and longer characteristic relaxation time (τ∗ = 1996.5 s) revealed by dynamic thermomechanical analysis indicated that crosslink networks were successfully formed by constructing coordination bonds. As a result, polyimide films' thermal resistance and dimensional stability were simultaneously enhanced. The typical PI-Cu50 films exhibited elevated glass transition temperatures of 353 °C (pristine PI-Cu0 ∼ 302 °C) and a lower CTE of 47.4 ppm/K (pristine PI-Cu0 films ∼ 64.4 ppm/K) in ranges of 300–400 °C, showing a promising application in the field of high-temperature environments.

The healing mechanism of diabetic foot wounds is very complicated, and it is difficult for a single-function medical dressing to achieve good therapeutic effects. We propose a simple coaxial biological 3D printing technology, which uses one-step 3D deposition to continuously produce multifunctional medical dressings on the basis of core–shell hydrogel fibers. These dressings have good biocompatibility, controlled drug-release performance, excellent water absorption and retention, and antibacterial and anti-inflammatory functions. In vivoexperiments with type 2 diabetic rats were performed over a 14-day period to compare the performance of the multifunctional 3D dressing with a gauze control; the multifunctional 3D dressing reduced inflammation, effectively increased the post-healing thickness of granulation tissue, and promoted the formation of blood vessels, hair follicles, and highly oriented collagen fiber networks. Therefore, the proposed multifunctional dressing is expected to be suitable for clinical applications for healing diabetic foot wounds.

Polyimide nanofiltration (NF) membranes with customizable chemical structures and excellent overall performance have attracted great interest in desalination and wastewater treatment. This work introduced novel Tin(II)-α-diimine coordination interactions to tailor the separation performance of polyimide NF membranes. Microstructural analysis confirmed the successful construction of coordination sites between Tin(II) and the diimine moieties. As expected, the resulting coordinated NF membranes exhibited uniform nanopores and reduced absolute negative charges on their surfaces, facilitating outstanding NF separation. The optimal coordinated polyimide NF membranes exhibited a high rejection rate of over 98% for methylene blue (MB) and a low rejection rate of less than 2% for NaCl and Na2SO4, demonstrating significant potential for application in dye desalination. Additionally, the obtained NF membranes demonstrate better long-term separation stability. As a preliminary study, this work provides a new strategy to modulate the microstructure and surface electric charge of NF membranes, potentially leading to greater application potential in dye desalination, seawater desalination, etc.

•Comprehensive analysis of the important role of ASB3 in the development of hepatocellular carcinoma.•Prediction of worse HCC prognosis by upregulated ASB3 levels, including overall survival (OS), progression free interval (PFI), and disease specific survival (DSS).•Over-expression of ASB3 may contribute to the development of HCC by affecting the immune environment of the tumor.•Elevated ASB3 levels can promote the invasive and metastatic ability of HCC.

Several new types of medical dressings have been developed thus far. However, most are two-dimensional membrane dressings which cannot be used to dress wounds of certain depths such as chronic ulcers and bedsores, and hence, cannot provide wound care. In this work, calcium alginate (Ca-Alg)–polyethylene glycol dipropylene ester (PEGDA) fibers and an injectable fibrous hydrogel were fabricated by microfluidic spinning. The morphology and diameter of the fibers were observed using a fluorescence inverted microscope and scanning electron microscope. The swelling properties under different conditions of the Ca-Alg–PEGDA fibrous hydrogels were tested at room temperature. The results showed that the fibers were arranged in orientation after injection. The diameters of the Ca-Alg–PEGDA fibers decreased with decreasing sodium alginate content. The swelling rate of the Ca-Alg–PEGDA fibrous hydrogels first increased and then decreased with increasing PEGDA content. The injectable Ca-Alg–PEGDA fibrous hydrogel has a three-dimensional network microstructure, which will be useful for filling and treating wounds of a certain depth, and potentially even for shortening the wound healing cycle.

The IR‐drop in the full AMOLED display panel caused by the pixel current is simulated within the mainstream SPICE toolkit to evaluate the display uniformity. Each electrical part of the display panel is simplified and equalized to allow the SPICE doing the very large scale calculation. The implementation of the full panel simulation and the results give better understanding of AMOLED panel design.

The bonded-particle model (BPM) is commonly used in the numerical analysis of ore samples. To improve the accuracy of simulating the mechanical process of ore process of ore crushing in a crusher, the parameters of the BPM for the ore must be calibrated. In this study, a calibration method was proposed for the scientific determination of the parameters of the BPM for ore undergoing uniaxial compression. First, physical tests and simulations were conducted to determine the mechanical response (uniaxial compressive strength and macroscopic stiffness) of ore during uniaxial compression. Then, the sensitivity of the mechanical response to the values of microscopic parameters was tested using a Plackett‒Burman design. Next, the microscopic parameters with the greatest impact on the response were identified, and the range of parameters that met the target response was determined using a steepest ascent design; Second, a second-order model of the mechanical response was established using the sensitive parameters by combining a Box‒Behnken design with response surface methodology to obtain the optimal BPM parameters. Simulation tests showed that the normal stiffness per unit area, critical shear stress, and bonded disk radius had significant effects on the uniaxial compressive strength (UCS) and macroscopic stiffness (MS). To verify the validity of the proposed calibration method, laboratory tests were conducted. The consistency of the simulation results with experimental results indicated that response surface methodology with the Plackett‒Burman design, steepest ascent design, and Box‒Behnken design can be an effective method for calibrating the BPM of ores.