It is widely accepted that nonmetalized organic gel fuel droplets exhibit characteristic and complicated oscillations during both evaporation and combustion, in contrast to the quasi-steady combustion of conventional liquid droplets. In this paper, an unsteady combustion model for the gel droplet is developed, taking into consideration the interactions between oscillating evaporation and flame structures. This model is first validated against experimental results for droplets of an organic gel based on unsymmetrical dimethylhydrazine (UDMH) burning in various nitrogen tetroxide (NTO) oxidizing atmosphere. Using this newly derived model and a detailed UDMH/NTO gas phase chemical reaction mechanism, the combustion characteristics of spray-sized UDMH gel droplets are numerically simulated and discussed in detail. The simulation and experimental results for droplet diameter and temperature both exhibit the same trend during the combustion process. The simulation error for droplet lifetime increases with both droplet size and ambient pressure as a consequence of neglecting heat conduction of the suspending thread and nonideal gas behavior in the model. Numerical simulation results for the detailed flow field parameter variations of the spray-size gel droplet combustion show obvious oscillations in both droplet radius and UDMH vapor mass fraction at the droplet surface following the formation of a gellant film. The oscillation frequency gradually decreases as the film thickness increases and the fuel is depleted. Although the double-flame temperatures and their standoff ratios also oscillate as the gellant film swells and ruptures, their relative oscillation amplitudes are smaller than those of the droplet radius and the vapor mass fraction at the droplet surface. The temperature of the gas phase flow field is higher when fuel vapor at the droplet surface is more abundant, but there is usually a time lag between the gas phase temperature reaching its maximum and the gellant film bursting within each swell-burst period because of the finite fuel vapor diffusion velocity. The temperature of the droplets continues to rise even after reaching the boiling point of liquid UDMH, since the boiling of the relatively small amount of liquid UDMH in a spray droplet cannot absorb all the heat flux from the flame.

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Long non-coding RNAs (lncRNAs) are non-coding RNAs of more than 200 nucleotides. To date, the roles of lncRNAs in soybean fatty acid synthesis have not been fully studied. Here, the low-linolenic acid mutant ‘MT72′ and the wild-type control ‘JN18′ were used as materials. The lncRNAs in young pods at 30 and 40 days (d) after flowering were systematically identified and analyzed using transcriptome sequencing technology combined with bioinformatics tools. A total of 39,324 lncRNAs and 561 differentially expressed lncRNAs were identified. A lncRNAs-miRNAs-protein-coding genes (mRNAs) network was constructed, and 46 lncRNAs, 46 miRNAs and 137 mRNAs were found to be correlated. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of 12 targeted mRNAs in the competing endogenous RNA network showed that these lncRNAs may be involved in the biological processes of fatty acid transport, lipid synthesis and cell division. Finally, the expression levels of differentially expressed lncRNAs, miRNAs and mRNAs were verified using qRT-PCR. The expression patterns of most genes were consistent with the sequencing results. In conclusion, new information was provided for the study of fatty acid synthesis by lncRNAs in young soybean pods.

AP3 has been studied and is reported to affect structural changes in floral organs in various plants. However, the function of the soybean AP3 genes in flower development is unknown. Here, the full-length cDNA sequence of GmAP3 was obtained by RACE and it was verified that it belongs to the MADS-box subfamily by a bioinformatics analysis. The expression of GmAP3 is closely related to the expression of essential enzyme genes related to flower development. Yeast two-hybrid assays demonstrated that GmAP3 interacts with AP1 to determine the identity of flower organ development. A follow-up analysis showed that overexpression of the GmAP3 gene advanced flowering time and resulted in changes in floral organ morphology. The average flowering time of overexpressed soybean and tobacco plants was 6–8 days earlier than that of wild-type plants, and the average flowering time of gene-edited soybean and tobacco plants was 6–11 days later than that of wild-type plants. In conclusion, GmAP3 may directly or indirectly affect the flower development of soybean. The results of this study lay the foundation for further research on the biological functions of MADS transcriptional factors in soybeans.

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