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Linearly polarized organic light-emitting diodes have become appealing functional expansions of polarization optics and optoelectronic applications. However, the current linearly polarized diodes exhibit low polarization performance, cost-prohibitive process, and monochromatic modulation limit. Herein, we develop a switchable dual-color orthogonal linear polarization mode in organic light-emitting diode, based on a dielectric/metal nanograting-waveguide hybrid-microcavity using cost-efficient laser interference lithography and vacuum thermal evaporation. This acquired diode presents a transverse-electric/transverse-magnetic polarization extinction ratio of 15.8 dB with a divergence angle of ±30°, an external quantum efficiency of 2.25%, and orthogonal polarized colors from green to sky-blue. This rasterization of dielectric/metal-cathode further satisfies momentum matching between waveguide and air mode, diffracting both the targeted sky-blue transverse-electric mode and the off-confined green transverse-magnetic mode. Therefore, a polarization-encrypted colorful optical image is proposed, representing a significant step toward the low-cost high-performance linearly polarized light-emitting diodes and electrically-inspired polarization encryption for color images. The authors present a switchable dual colour orthogonal linear polarized OLED by internally integrating a nanograting for selective diffraction of optical modes, which is appealing for applications including polarisation-encrypted colourful optical images and autostereoscopic naked-eye 3D displays.

In coal mines, underground reservoir systems can increase the availability of water and are an effective technical approach for the protection and utilization of water resources. The stability of coal pillar dams is the key factor in the safety and stability of these underground water storage systems. However, coal pillar dams must operate in complex environments that combine dynamic-static superimposed stress fields and water immersion; moreover, coal pillar dams subjected to both stress and seepage are more susceptible to damage and even collapse. In this study, a seepage-stress coupling model of a coal pillar dam was constructed using the Universal Distinct Element Code (UDEC) simulation software. This model provides a platform for analyzing the characteristics of fracture development in surrounding rock in active mines and the coupled development of crack fields and seepage fields in coal pillar dams. Methods were developed for (1) calculating the water content for the coal pillar dam numerical simulation model and (2) reducing water immersion weakening. The maximum seepage width of a coal pillar dam subjected to water immersion was obtained, and a damage and failure evolution mechanism for coal pillar dams experiencing flooding was developed. The results provide a scientific basis for enhancing the stability control of coal pillar dams and are of great significance for realizing water conservation in coal mines.

Highlights Nanoimprint lithography (NIL) enables high-performance light management in organic light-emitting diodes and organic solar cells, and enhances charge transport in organic field-effect transistors via controlled molecular ordering, pushing organic optoelectronics beyond conventional efficiency limits. The technology provides a scalable, low-cost platform for large-area fabrication on flexible substrates, effectively bridging the gap between laboratory innovation and industrial mass production. NIL uniquely empowers the creation of multifunctional integrated devices and novel architectures, opening pathways for next-generation wearable electronics and bio-integrated systems. Organic optoelectronic devices demonstrate immense potential in flexible displays, wearable electronics, and artificial skin, needing precise light-field and morphology management strategies to further improve their opto-electric performance. Nanoimprint lithography (NIL) has emerged as a high-resolution, high-efficiency, and low-cost patterning technique that mechanically transferring micro/nanoscale patterns from a template to a substrate to significantly enhance the optoelectronic performance through the precise creation of advanced light-management structures, combined with additional solid-state stacking morphology. This review systematically summarizes recent advances in NIL technology for organic optoelectronics. It begins with an introduction to the fundamental principles, main process variants (thermal, ultraviolet, and electrochemical NIL), as well as key technical issues. Subsequently, through specific applications in organic light-emitting diodes, organic solar cells, and organic field-effect transistors, it highlights the exceptional capabilities of NIL to enhance device performance by controlling crystallization and creating functional micro/nanostructuring. Specific advantages include enabling high-efficiency light management to overcome efficiency bottlenecks, facilitating low-cost, high-throughput manufacturing for industrialization, full compatibility with flexible substrates for emerging applications, enabling multifunctional integration and novel device architectures, and tailoring material microstructures and properties advance fundamental research. Finally, we discuss the remaining challenges and future prospects of NIL in integrated organic optoelectronic systems.

Limited-angle computed tomography (CT) image reconstruction is a challenging problem in the field of CT imaging. In some special applications, limited by the geometric space and mechanical structure of the imaging system, projections can only be collected with a scanning range of less than 90°. We call this kind of serious limited-angle problem the ultra-limited-angle problem, which is difficult to effectively alleviate by traditional iterative reconstruction algorithms. With the development of deep learning, the generative adversarial network (GAN) performs well in image inpainting tasks and can add effective image information to restore missing parts of an image. In this study, given the characteristic of GAN to generate missing information, the sinogram-inpainting-GAN (SI-GAN) is proposed to restore missing sinogram data to suppress the singularity of the truncated sinogram for ultra-limited-angle reconstruction. We propose the U-Net generator and patch-design discriminator in SI-GAN to make the network suitable for standard medical CT images. Furthermore, we propose a joint projection domain and image domain loss function, in which the weighted image domain loss can be added by the back-projection operation. Then, by inputting a paired limited-angle/180° sinogram into the network for training, we can obtain the trained model, which has extracted the continuity feature of sinogram data. Finally, the classic CT reconstruction method is used to reconstruct the images after obtaining the estimated sinograms. The simulation studies and actual data experiments indicate that the proposed method performed well to reduce the serious artifacts caused by ultra-limited-angle scanning.

Two-dimensional transition metal carbides and/or nitrides (MXenes), especially their few-layered nanosheets, have triggered burgeoning research attentions owing to their superiorities including extraordinary electrical conductivity, accessible active surface, and adjustable processability. Molten salts etching route further achieves their controllable surface chemistry. However, the method encounters challenges in achieving few-layered structures due to more complex delamination behaviors. Herein, we present an efficient strategy to fabricate Cl- or Br-terminated MXene nanoflakes with few-layers, achieved by electrochemical intercalation of Li ions and concomitant solvent molecules from the electrolyte solution, with gaseous propylene molecules to disrupt interlayer forces. By controlling cut-off voltages, the optimal protocol results in nanosheets with a recovery rate of ~93% and preserved surface chemistry. The resultant MXenes dispersions were employed as lubricants to enhance tribovoltaic nanogenerators, where Ti 3 C 2 Br 2 displayed superior electrical output. These findings facilitate the understanding of MXenes’ intrinsic physical properties and enable the nanoengineering of advanced electronic devices. This work demonstrates an efficient electrochemical exfoliation approach to achieve high recovery rate for few-layered halogenated MXenes by leveraging gaseous propylene molecules as ‘physical scissors’, to enable advanced tribovoltaic nanogenerators.

A thin coal seam mined as a protective coal seam above a gas outburst coal seam plays a central role in decreasing the degree of stress placed on a protected seam, thus increasing gas permeability levels and desorption capacities to dramatically eliminate gas outburst risk for the protected seam. However, when multiple layers of coal seams are present, stress-relieved gas from adjacent coal seams can cause a gas explosion. Thus, the post-drainage of gas from fractured and de-stressed strata should be applied. Comprehensive studies of gas permeability evolution mechanisms and gas seepage rules of protected seams close to protective seams that occur during protective seam mining must be carried out. Based on the case of the LongWall (LW) 23209 working face in the Hancheng coal mine, Shaanxi Province, this paper presents a seepage model developed through the FLAC3D software program (version 5.0, Itasca Consulting Group, Inc., Minneapolis, MI, USA) from which gas flow characteristics can be reflected by changes in rock mass permeability. A method involving theoretical analysis and numerical simulation was used to analyze stress relief and gas permeability evolution mechanisms present during broken rock mass compaction in a goaf. This process occurs over a reasonable amount of extraction time and in appropriate locations for comprehensive gas extraction technologies. In using this comprehensive gas drainage technological tool, the safe and efficient co-extraction of thin coal seams and gas resources can be realized, thus creating a favorable environment for the safe mining of coal and gas outburst seams.

Bidirectional displays, capable of simultaneous front and rear illumination, enable transformative applications such as see‐through retail displays, intelligent signage, and next‐generation foldable devices. Despite their potential, the inherent trade‐off between transparency and brightness, coupled with imbalanced bidirectional emission, has hindered the advancement of bidirectional viewing organic light‐emitting diodes (BV‐OLEDs). Here, we present a dual‐approach strategy to achieve simultaneously improved and balanced bidirectional emission with quasi‐Lambertian distribution in bidirectional emitting OLEDs. By combining a microcavity resonance enhancement through nano‐patterned structures and a dielectric/metal/dielectric (DMD) capping layer for improved top electrode transmittance, we effectively suppress surface plasmon and waveguide modes in OLED devices. Consequently, the optimized nanoimprinted DMD electrode achieved a remarkable 89.7% enhancement in transmittance (from 33.9% to 64.3% at 664 nm) compared to conventional planar electrodes; and the resulting BV‐OLED demonstrated balanced bidirectional emission from 33% to 42% with a 67.3% total brightness increase, while exhibiting enhanced transparency with nearly zero haze, quasi‐Lambertian radiation pattern, and excellent color stability across a 120° viewing angle. This breakthrough establishes a fundamental design framework for bidirectional displays, bridging conventional dual‐panel technologies with emerging applications in next‐generation transparent and flexible display systems. We present a dual‐approach strategy for high‐performance bidirectional‐viewing OLEDs, combining enhanced cavity resonance with a nanoimprinted dielectric/metal/dielectric (DMD) electrode. This bidirectional viewing OLED presents an 89.7% enhanced electrode transmittance, a balanced bidirectional emission ratio with 67.3% total brightness increase, as well as quasi‐Lambertian distribution featuring zero haze and stable color performance within 120° viewing angle.

Two diastereoisomers (NTPH-P and NTPH-T1) as a C 2 -symmetric triple [5]helicene based on N -annulated triperylene hexaimide were synthesized. Aided by nuclear magnetic resonance spectroscopy (NMR) and theoretical calculations, NTPH-P was assigned to three-blade propeller conformation while NTPH-T1 tended to exhibit twisted conformation with pyrrole ring fusing on a bowl-shaped PDI foil. Characterized by circular dichroism (CD) and circular polarized luminescence (CPL) measurements, the enantiomerically pure NTPH-P exhibited fairly good chiral activities both in the absorption and emission range with dissymmetry factors ∣g abs ∣ of 4.1×10 −3 and ∣g lum ∣ of 1.2×10 −3 . The diastereoisomers were further employed as acceptors for organic solar cells with distinct PCEs of 8.11% and 5.24% for NTPH-P and NTPH-T1 based devices, respectively, signifying the prospects in chiroptical electronics by designing molecularly defined aromatics.

Algorithms working in mode space instead of directly matching the received complex sound pressure were developed to improve computational efficiency and robustness, but these algorithms may be inconvenient to apply in practice because manual operations are often inevitable when performing modal filtering. Based on a phase-matched filter, an imperfect matching scheme named the modal phase based matched impulse response (MP-MIR) is proposed to estimate the source range rapidly and conveniently with a single hydrophone. The field to be matched is still the received complex sound pressure. The replica field is a sum of several “phase” modes, which can be efficiently and conveniently synthesized merely with the horizontal wavenumbers of normal modes and the source–receiver range. The effectiveness of the proposed MP-MIR was demonstrated in localizing 84 emissions along a weakly range-dependent track at ranges of 2.54–20 km in the South China Sea. Although it was found, from cross-correlation coefficients, that the received signals showed strong variation even between adjacent emissions, MP-MIR outperformed the classical matched impulse response (MIR) with a lower standard deviation in most cases, demonstrating good robustness and potential for practical applications.

Automatic schematic generation is a key aspect of reverse engineering for printed circuit boards, and its cost is usually proportional to the size of the circuit. The generation of schematics for large-scale, realistic netlists poses a significant challenge within this domain. Netlist partitioning is a major approach to addressing this challenge. It reduces the cost of schematic generation by segmenting netlists into sub-netlists of moderate size based on their functional modules. Traditional methods that utilize expert systems for netlist partitioning exhibit high sensitivity to parameters and demonstrate poor adaptability across different netlists. Furthermore, their experimental data are typically constructed manually, making them difficult to reproduce. To address these limitations, this article first presents a set of graph datasets designed specifically for netlist partitioning experiments. Second, to tackle the neighborhood bias problem prevalent in real circuit netlists, we propose a novel neighborhood bias edge pruning algorithm called BiN-EdgePruning. Building on this foundation, we integrate BiN-EdgePruning with graph convolutional networks to achieve end-to-end netlist partitioning, thereby eliminating the need for unnecessary parameter tuning. Experimental results demonstrate that the proposed pruning algorithm significantly enhances the accuracy of printed circuit netlist partitioning across various graph neural network architectures.