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The music industry's development and innovation are vital for expanding music education channels and enhancing cultural and artistic innovation. To achieve digital and intelligent music teaching tailored to students' needs, this study developed a music automatic generation model using pre-training and transfer learning. By integrating semantic analysis and user differences, the model offers enhanced personalised features. Performance analysis indicates high precision and recall rates at 91.49% and 88.42% respectively, with average errors below 0.550 and 0.450. The model's quality has significantly improved, providing personalised music that aligns with user needs. Through subjective and objective evaluations, the model's generated music demonstrated good quality. Overall, this model boosts music creation efficiency, fosters innovative music art development, expands music education outlets, enhances beginners' understanding of music creation processes, and popularises music education.

Succinic acid, as one of the important fermentation products, is commonly used as an acidulant, flavoring agent, and antimicrobial agent. However, the accumulation of organic acids in the later fermentation phase will restrict the production efficiency of strain. To address this issue, the directed evolution on the key transcription morphology factor bolAgene was performed to enhance acid resistance of Escherichia coliby ep-PCR library and CRISPR/Cas9. The best mutant strain 5-21-5 was screened from 4000 mutant colonies ep-PCR library, which showed higher cell survives in succinic acid stress. Its acid resistance ability was systematically illustrated from multiple aspects by transmission electron microscope (TEM), confocal laser scanning microscopy (CLSM), and three-dimensional excitation emission matrix (3D-EEM) analysis, respectively. Higher tyrosine and tryptophan protein level was beneficial to acid resistance, while cell tend to short rod shape. Subsequently, with the assistance of the CRISPR/Cas9 gene editing technology knocking the mutated sequences into the genome, the succinic acid yield of strain M-K10 reached 9.8 g/L, representing a 15.29% increase compared to the Escherichia coliMG1655 without gene editing.

Heat resistance is a basic and crucial characteristic of energetic materials (EMs), and always accounted in development and application. Compared with the clear origin of the high heat resistance of EMs, the mechanism for the low heat resistance remains still unclear. This work reveals the mechanism by carrying reactive molecular dynamics simulations on heating six less thermally stable EMs of nitroforms and pentaerythritol tetranitrate (PETN), as well as a more thermally stable EM of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) for comparison. Unexceptionally, all the nitroforms and PETN heated feature fast NO2partition and further decomposition throng the oxidation of NO2to form small fragments and final small stable product molecules, with fast heat release; while, the intermolecular reactions and the further clustering govern the initial steps in decomposing TATB. Therein the reactants also exhibit a rapid consumption; however, this fast consumption with clustering does not result in the low heat resistance of TATB. That is, some general indicators representative of thermostability, such as bond dissociation energy and the reactant consumption rate, are insufficient to assess it practically. Thus, the rapid fragmentation originally contributes to the low heat resistance. These insights are expected to present an overall perspective of understanding the thermal stability mechanism of EMs, and set a theoretical base and pave a way for designing EMs with desired heat resistance.

Highly thermostable energetic materials (EMs) are highly desired for deep underground and space exploration, and therefore have attracted much attention. This work employs four typical traditional EMs composed of C, H, N and O atoms as example to clarify the origin of high heat resistance, by means of molecular dynamics simulations with the molecular reactive forcefield of ReaxFF. These EMs include 3,5-dinitro-N,N´-bis(2,4,6-trinitrophenyl)pyridine-2,6-diamine (PYX), 1,3,5-diamino-2,4,6-trinitrobenzene (TATB) and 2,2´,4,4´,6,6´-hexanitrostilbene (HNS), which are highly thermostable with decomposition temperature peaks > 600 K, and a less one of pentaerythritol tetranitrate (PETN) for comparison. It is found that the clustering in the decomposition of PYX, TATB and HNS retards the extraction of small product molecules from clusters, as well as heat release, and thereby roots for their high heat resistance; while, the clustering in the PETN decay is negligible and heat release and fragmentation proceed rapidly, facilitating to fast decomposition. Combining this finding with the well-known molecular stability, this work presents a perspective on the high heat resistance of traditional EMs. Based on it, a highly negative oxygen balance, a high C content and a high molecular stability are proposed as a strategy for designing and constructing new highly heat-resistant EMs.

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