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Purposes The development of information technology has significantly impacted economic, political, cultural, and military fields, and the information security is of great importance in modern society. Deep information-hiding, i．e. hiding the confidential information in an overt carrier, is one of the most important approach in improving information security and has been driving long research efforts in material science, communication technology and cryptology. Organic stimuli-responsive luminescent (SRL) materials that change their luminescence in response to mechanical force, thermal treatment, and light or pH value are considered as promising media candidates. Among them, the materials that exhibit SRL turn-on capabilities have shown advanced performances such as high contrast and signal to noise ratio, and aroused enormous interest. Methods The recent progress of SRL turn-on materials based on the MRL mechanisms and performances is reviewed following the sequence from changes in molecular structure to modifications in aggregate structure. A systematic summary of the material system is provided. Conclusions The existing challenges facing high-performance MRL turn-on materials, including the development of luminescence mechanisms, regulation of kinetic process and control of multi-phase state transitions are elaborated and rational solution are proposed. It will provide theoretical insights and practical experiences for the design, synthesis, and application of novel high-performance SRL materials.

Firstly, an in-depth analysis is conducted on the principle of crack formation in the pavement panel of highway and railway level crossings and the reasons for cracks under load. Then, based on the characteristics of crack formation in the pavement panel, structural optimization design is carried out on the pavement panel, and finite element analysis is conducted on the optimized structure to verify whether the optimization is reasonable, reduce the occurrence of cracks in the pavement panel of highway and railway level crossings, and extend the service life of the pavement panel.

The residue behaviours of difenoconazole, bifenthrin, thiamethoxam and its metabolite clothianidin on representative crops such as cucumber, bitter gourd, loofah, zucchini, tomato, cherry tomato, eggplant, cowpea, kidney bean, celery, and fennel were investigated. The effects of factors such as fruit size, property of epidermis, leaf size and others on pesticide residues were studied, and then analysed whether these crops are suitable for the same group. Results indicated residue extrapolation could be made between the different crop groups or subgroups. It could be extrapolated from high-risk residue crops to the low-risk residue crops. Cherry tomato or eggplant could be extrapolated to tomato, and bitter gourd or loofah could be extrapolated to cucumber or zucchini, and the reverse was unacceptable. For these four vegetable groups, the different edible parts led to a significant difference in pesticide residues, celery and fennel had higher residue risk because the edible parts were whole plants including the leaves. The residue difference in the same edible parts of the different crop groups was not obvious, such as the Fruiting vegetables, Cucurbits group and the Fruiting vegetables, other than Cucurbit group. The processing factor (PF) extrapolation was more reasonable because crop varieties had no significant effect on pesticide residues in processed commodities. From the perspective of pesticide residues, representative crops were proposed and the rationality of crop classification and residue extrapolation was analysed. These results could promote the process of pesticide registration and the settlement of Maximum Residue Limit (MRL) standards, and further solve the missing of MRL for minor crops. [ABSTRACT FROM AUTHOR]