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Abstract This paper presents a kernel extreme learning machine (KELM) integrated with the improved whale optimization algorithm (IWOA) to address the power quality disturbance (PQD) issue in microgrids. First, an adaptive variational mode decomposition method is employed to extract PQD signals in microgrids. Then, the IWOA is utilized to optimize the penalty factor and kernel function parameters for the KELM classifier model, thereby enhancing the performance of the classifier. Furthermore, the test results indicate that the proposed IWOA–KELM achieves high classification accuracy and rapid convergence for complex PQD signals.

Abstract Colloidal quantum dots (CQDs) are promising optoelectronic materials for solution‐processed thin film optoelectronic devices. However, the large surface area with abundant surface defects of CQDs and trap‐assisted non‐radiative recombination losses at the interface between CQDs and charge‐transport layer limit their optoelectronic performance. To address this issue, an interface heterojunction strategy is proposed to protect the CQDs interface by incorporating a thin layer of polyethyleneimine (PEIE) to suppress trap‐assisted non‐radiative recombination losses. This thin layer not only acts as a protective barrier but also modulates carrier recombination and extraction dynamics by forming heterojunctions at the buried interface between CQDs and charge‐transport layer, thereby enhancing the interface charge extraction efficiency. This enhancement is demonstrated by the shortened lifetime of carrier extraction from 0.72 to 0.46 ps. As a result, the resultant PbS CQD solar cells achieve a power‐conversion‐efficiency (PCE) of 13.4% compared to 12.2% without the heterojunction.

Abstract In order to supply benefits for safe production of coal underground and efficient exploitation of coalbed methane, a self‐developed gas seepage experimental device considering gas adsorption and desorption was proposed to study the seepage properties of gas‐saturated coal in this paper. A series of gas seepage experiments under different loading conditions were carried out to investigate the change rules of permeability of gas‐saturated coal. The experimental results covered the significant effects of confining pressure, gas pressure, temperature change, creep stress, and complete stress‐strain process on the seepage laws of gas‐saturated coal. The experimental results showed that the permeability of gas‐saturated coal is strongly sensitive to the effective stress and decreases with the increase of the effective stress. Under the fixed confining pressure, the permeability of gas‐saturated coal showed an obvious Klinkenberg effect, but the Klinkenberg effect would no longer be evident once the gas pressure was larger than 1.0 MPa. And the change law of permeability of gas‐saturated coal with temperature was mainly reflected in the comprehensive effect of thermal stress and effective stress on the control of pore deformation. Under the complete stress‐strain loading conditions, the change rules of permeability were mainly dependent on the failure mode of gas‐saturated coal. And the change rules of permeability, for the condition of triaxial creep stress, were relied on the stage of creep deformation. The deformation at decay creep stage was responsible for a steady permeability after the failure of gas‐saturated coal, while the deformation at nondecay creep stage was responsible for a rapid increase of permeability after the failure of gas‐saturated coal. The results in this work can offer some helpful suggestions for efficiently exploring coalbed methane in the future.

Abstract Cuticular waxes play important eco‐physiological roles in protecting plants against abiotic and biotic stresses and show high sensitivity to environmental changes. In order to clarify the responses of cuticular waxes on faba bean (Vicia faba L.) leaves to different light wavelengths, the phenotypic plasticity of cuticular waxes was analyzed when plants were subjected to white, red, yellow, blue, and purple light. Leaf samples from yellow, purple, and white lights were further analyzed, and candidate genes of wax biosynthesis were selected by RNA‐seq technology and transcriptome processing. Yellow light increased the total wax coverage and changed the crystal structure compared with leaves under white light. Light wavelengths changed the relative abundance of dominant primary alcohol from C24 under white, yellow, and red lights to C26 under blue and purple lights. In total, 100,194 unigenes were obtained, and 10 genes were annotated in wax biosynthesis pathway, including VLCFAs elongation (KCS1, KCS4, LACS2 and LACS9), acyl reduction pathway (FAR3 and WSD1), and decarboxylation pathway (CER1, CER3 and MAH1). qRT‐PCR analysis revealed that yellow and purple lights significantly influenced the expression levels of these genes. Yellow light also increased the water loss rate and decreased the photosynthesis rate. Light at different wavelengths particularly yellow light induced the changes of phenotypic plasticity of cuticular waxes, which thus altered the leaf eco‐physiological functions. The expression levels of genes related to wax biosynthesis were also altered by different light wavelengths, suggesting that light at different wavelengths may also be applied in selecting candidate genes involved in wax biosynthesis in other crops.