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Anthraquinone dyes are the second most important type of dyes after azo dyes. In particular, 1-aminoanthraquinone has been extensively utilized in the preparation of diverse anthraquinone dyes. This study employed a continuous-flow method to synthesize 1-aminoanthraquinone safely and efficiently through the ammonolysis of 1-nitroanthraquinone at high temperatures. Various conditions (reaction temperature, residence time, molar ratio of ammonia to 1-nitroanthraquinone (M-ratio), and water content) were investigated to explore the details of the ammonolysis reaction behavior. Operation conditions for the continuous-flow ammonolysis were optimized using Box–Behnken design in the response surface methodology, and ~88% yield of 1-aminoanthraquinone could be achieved with an M-ratio of 4.5 at 213 °C and 4.3 min. The developed process’s reliability was evaluated by performing a 4 h process stability test. The kinetic behavior for the preparation of 1-aminoanthraquinone was investigated under continuous-flow mode to guide the reactor design and to gain a deeper understanding of the ammonolysis process.

The KNOX genes play important roles in maintaining SAM and regulating the development of plant leaves. However, the TaKNOX genes in wheat are still not well understood, especially their role in abiotic stress. In this study, a total of 36 KNOX genes were identified, and we demonstrated the function of the TaKNOX14-D gene under mechanical injury and cold stress. Thirty-six TaKNOX genes were divided into two groups, and thirty-four TaKNOX genes were predicted to be located in the nucleus by Cell-PLoc. These genes contained five tandem duplications. Fifteen collinear gene pairs were exhibited in wheat and rice, one collinear gene pair was exhibited in wheat and Arabidopsis. The phylogenetic tree and motif analysis suggested that the TaKNOX gene appeared before C3 and C4 diverged. Gene structure showed that the numbers of exons and introns in TaKNOX gene are different. Wheat TaKNOX genes showed different expression patterns during the wheat growth phase, with seven TaKNOX genes being highly expressed in the whole growth period. These seven genes were also highly expressed in most tissues, and also responded to most abiotic stress. Eleven TaKNOX genes were up-regulated in the tillering node during the leaf regeneration period after mechanical damage. When treating the wheat with different hormones, the expression patterns of TaKNOX were changed, and results showed that ABA promoted TaKNOX expression and seven TaKNOX genes were up-regulated under cytokinin and auxin treatment. Overexpression of the TaKNOX14-D gene in Arabidopsis could increase the leaf size, plant height and seed size. This gene overexpression in Arabidopsis also increased the compensatory growth capacity after mechanical damage. Overexpression lines also showed high resistance to cold stress. This study provides a better understanding of the TaKNOX genes.