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The motion of near-wall bubble-in-chain, which is a crucial aspect of the study of near-wall bubble flows, involves not only the wall effect but also the interactions between bubbles. However, there have been few studies on this topic. In this study, we investigated the motion of near-wall bubble-in-chain using a dual-camera orthogonal shadow method and tracked bubbles using image processing and feature matching techniques. Considering both the wall effect and bubble generation frequency, we discussed the statistical characteristics, motion modes, dynamic characteristics, and energy evolution of bubbles. The results demonstrate that an increase in bubble generation frequency leads to a greater deviation of bubble trajectories from the wall and an increase in trajectory amplitude while weakening the suppression of bubble speed by the wall. Furthermore, changes in both bubble equivalent diameter and drag coefficient reveal how bubble generation frequency affects their shape stability during motion as well as regulation by the wall effect. The drag coefficient decreases with increasing Reynolds number for bubbles; however, an increase in bubble generation frequency broadens its distribution range. Additionally, it is evident that the wall effect significantly impacts drag characteristics for bubbles: uncollided bubbles experience increased drag coefficients with greater distance from the wall while collided bubbles exhibit decreased drag coefficients. In cases of high generation frequency, the conversion of kinetic energy to surface energy during bubble collisions, especially the enhancement of the peak of surface energy, indicates an increase in the bubble's energy storage capacity and energy conversion efficiency. The findings not only enhance comprehension of behavior exhibited by near-wall bubbles but also offer a novel perspective for regulating near-wall bubble flows in industrial applications. [ABSTRACT FROM AUTHOR]

PURPOSE AND METHODS: Botrytis cinerea is the primary disease affecting cucumber production. It can be managed by applying pesticides and cultivating disease‐resistant cucumber strains. However, challenges, such as drug resistance in pathogenic bacteria and changes in physiological strains, are obstacles in the effective management of B. cinerea. Nano‐selenium (Nano‐Se) has potential in enhancing crop resistance to biological stress, but the exact mechanism for boosting disease resistance remains unclear. Here, we used metabolomics and transcriptomics to examine how Nano‐Se, as an immune activator, induces plant resistance. RESULT: Compared with the control group, the application of 10.0 mg/L Nano‐Se on the cucumber plant's leaf surface resulted in increased levels of chlorophyll, catalase (10.2%), glutathione (326.6%), glutathione peroxidase (52.2%), cucurbitacin (41.40%), and metabolites associated with the phenylpropane synthesis pathway, as well as the total antioxidant capacity (21.3%). Additionally, the expression levels of jasmonic acid (14.8 times) and related synthetic genes, namely LOX (264.1%), LOX4 (224.1%), and AOC2 (309.2%), were up‐regulated. A transcription analysis revealed that the CsaV3_4G002860 gene was up‐regulated in the KEGG enrichment pathway in response to B. cinerea infection following the 10.0 mg/L Nano‐Se treatment. DISCUSSION: In conclusion, the activation of the phenylpropane biosynthesis and branched‐chain fatty acid pathways by Nano‐Se promotes the accumulation of jasmonic acid and cucurbitacin in cucumber plants. This enhancement enables the plants to exhibit resistance against B. cinerea infections. Additionally, this study identified a potential candidate gene for cucumber resistance to B. cinerea induced by Nano‐Se, thereby laying a theoretical foundation for further research in this area. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The polylactic acid-glycolic acid copolymer (PLGA) has been proven to be applicable in medicine, but there is limited research on its application and safety in the agricultural field. In this paper, thifluzamide PLGA microspheres were prepared via phacoemulsification and solvent volatilization, using the PLGA copolymer as the carrier and thifluzamide as the active component. It was found that the microspheres had good slow-release performance and fungicidal activity against Rhizoctonia solani. A comparative study was conducted to show the effect of thifluzamide PLGA microspheres on cucumber seedlings. Physiological and biochemical indexes of cucumber seedlings, including dry weight, root length, chlorophyll, protein, flavonoids, and total phenol content, indicated that the negative effect of thifluzamide on plant growth could be mitigated when it was wrapped in PLGA microspheres. This work explores the feasibility of PLGA as carriers in fungicide applications. [ABSTRACT FROM AUTHOR]

Due to the deficiency in using the cross-bonded grounding mode, a large circulating current is usually induced in the metal sheaths and armors, reducing the permissible current rating of submarine cables. To address this issue, this paper proposes a novel grounding mode to suppress these circulating currents and enhance the permissible current rating within the voltage limits of metal sheaths and armors. To achieve the best performance of the novel grounding mode, the optimal grounding impedances are given. Theoretical analyses indicate that for general submarine cables, the novel grounding mode can suppress the circulating currents within the voltage limits compared with the two-ends grounding mode, and can reduce the short-circuit terminal voltage of metal sheaths and armors compared with the non-interlinked version of the proposed mode. The numerical results further validate the better comprehensive performances of the novel grounding mode in reducing the power loss and short-circuit overvoltage. [ABSTRACT FROM AUTHOR]