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Organic luminogens have extensive applications due to their unique photophysical properties. In recent years, nonconjugated organic luminogens, in contrast to traditional conjugated luminogens, have gained much attention because of their facile preparation, environmental friendliness, and biocompatibility. In this study, a new kind of nonconventional luminogen based on dynamic covalent cross-linked polyhydroxyurethane is reported for the first time. The new luminogen not only exhibits intrinsic strong fluorescent emission in the solid state but also possesses high mechanical properties along with good shape memory and self-healing properties. In addition, the new luminogens are synthesized from aliphatic polyfunctional cyclic carbonate and amines via a much more straightforward method, avoiding the use of toxic isocyanates. Investigations indicated that the intrinsic luminescence of the resultant luminogens was induced by the cross-linking of polymer chains and could be well tuned by controlling the degree of cross-linking. By taking advantage of the unique characteristics of the resultant polymer luminogens, we further developed a facile method, named "light-mediated ink-free screen printing", for anticounterfeiting paper fabrication. Different from traditional ink-based printing technology, the new method used UV-light instead of expensive security ink to encode anticounterfeiting information on natural cellulose paper. The anticounterfeiting information is stable under various wet conditions, showing promising applications in the fast-growing counterfeiting of pharmaceuticals, packaging, and the food industry.

This article investigates the effects of the processing conditions of the novel sintering and dissolution process (SDP), including sintering temperature, sintering time, Mg addition, and cell size, on the capacities of the as-processed Al foams for static and dynamic energy absorption. While higher temperatures generally promote better bonding between the Al particles during sintering and, therefore, improved energy-absorption capacities, there exist optimum sintering times and cell-size ranges for producing Al foams with the best energy-absorption characteristics. The optimum sintering time increases when the sintering temperature or the relative density is decreased. The addition of a small amount of Mg powder to the Al/NaCl compact can enhance the sintering markedly and increase the energy-absorbing capacity of the foam by up to 50 pct. For any Al foam, the energy absorbed in the static condition is much greater than that in the dynamic condition. The mechanisms of these effects are also discussed.

A new method to enhance the compressive strength of corrugated cartons is proposed in this study. The work aims to carry out compression tests on the corrugated carton to analyze the deformation and compressive capacity of the carton under the indentation condition of different shapes. First, compression tests are carried out on nonindentation cartons, one-line indentation cartons, unclosed rhombus indentation cartons, rhombus indentation cartons, and cross-indentation cartons to record their maximum compressive force. Second, by comparing the deformation of different cartons, it is found that rhombus indentation and cross-indentation have the greatest influence on the compressive strength of cartons. Rhombus indentation will enhance the compressive strength of the carton, while cross-indentation will reduce it. Third, ANSYS Workbench is used to analyze the buckling of cartons, and the maximum compressive force of nonindentation cartons and rhombus indentation cartons is obtained. Finally, through the comparison of the finite element method and experiments, it is concluded that rhombus indentation can improve the compressive strength of cartons, which is of great significance to the industrial production of cartons.