The development of organic afterglow materials with high environmental stability and multi-mode luminescence remains a significant challenge in luminescent anti-counterfeiting.In this work,an organic luminescent molec...The development of organic afterglow materials with high environmental stability and multi-mode luminescence remains a significant challenge in luminescent anti-counterfeiting.In this work,an organic luminescent molecule was encapsulated within polyacrylamide microspheres and embedded in a gold nanorod-doped,ferric ion-crosslinked hydrogel exhibiting upper critical solution temperature behavior.The obtained composites exhibited fluorescence,thermally activated delayed fluorescence,and phosphorescence.Through the application of extrusion or uniaxial stretching,the orientation of the gold nanorods was modulated,enabling polarization-dependent luminescence through transverse surface plasmon resonance absorption.At 300%uniaxial strain,the polarized fluorescence intensity difference at 520 nm reached 0.29.Furthermore,ultraviolet irradiation was employed to locally disrupt the orientation of the gold nanorods,resulting in depolarization within the irradiated regions.These areas displayed non-polarized fluorescence,while the non-irradiated regions retained both emission and fluorescence polarization characteristics.Localized imprinting was employed to modulate material thickness,thereby controlling the density of gold nanorods.Thinner regions exhibited weaker transverse localized surface plasmon resonance absorption,while thicker regions showed stronger absorption,enabling the coexistence of blue–green fluorescence and polarization patterns.Local humidification effectively reduced phosphorescence intensity,enhancing the material's environmental responsiveness.The composite demonstrated excellent reversibility over multiple stretching–selfhealing cycles and pattern-switching processes,highlighting its strong potential for multidimensional optical encryption and intelligent anticounterfeiting applications.展开更多
The yellow peach moth, Conogethes punctiferalis （Guenee）, a multivoltine species that overwinters as diapausing larvae, is one of the most serious insect pests on maize in China. Effect of photoperiod and temperatur...The yellow peach moth, Conogethes punctiferalis （Guenee）, a multivoltine species that overwinters as diapausing larvae, is one of the most serious insect pests on maize in China. Effect of photoperiod and temperature on larval diapause was examined under empirical laboratory conditions. Short-day treatments caused larval diapause at 25℃, and the critical photoperiod was between 12 and 13 h （or 12 h 51 min） light per day. No sensitive instar was identified for diapause induction under alternated short- （L ： D 11 ： 13 h） and long-day （L ： D 14 ： 10 h） treatments at different larval stages. However, accumulative treatment of three instars and 10 d under short-day treatment was required for the induction of 50% larval diapause. All larvae entered diapause at 20℃, whereas less than 3% did so at 30℃, irrespective of the long- or short-day treatment. Furthermore, under the short-day treatment, more than 90% of larvae went into diapause with temperatures ≤ 25℃, but less than 17% did so at 28℃. In contrast, under the long-day treatment, less than 19% of larvae went into diapause with temperatures ≥23 ℃. The forward shift （5℃） of critical temperature under the long-day regime demonstrated the compensatory effect of temperature and photoperiod on diapause induction. In conclusion, C. punctiferalis had a temperature-dependent type Ⅰ photoperiodic diapause response; there was no sensitive instar for diapause determination, but the photoperiodic accumulation time countermeasures both of the short-day cycles and the number ofinstars exposed, and the photoperiodic diapause response, was a temperature-compensated phenomenon.展开更多
基金financially supported by the National Key R&D Program of China(No.2023YFB3812400)the National Natural Science Foundation of China(Nos.52203353 and52433004)。
文摘The development of organic afterglow materials with high environmental stability and multi-mode luminescence remains a significant challenge in luminescent anti-counterfeiting.In this work,an organic luminescent molecule was encapsulated within polyacrylamide microspheres and embedded in a gold nanorod-doped,ferric ion-crosslinked hydrogel exhibiting upper critical solution temperature behavior.The obtained composites exhibited fluorescence,thermally activated delayed fluorescence,and phosphorescence.Through the application of extrusion or uniaxial stretching,the orientation of the gold nanorods was modulated,enabling polarization-dependent luminescence through transverse surface plasmon resonance absorption.At 300%uniaxial strain,the polarized fluorescence intensity difference at 520 nm reached 0.29.Furthermore,ultraviolet irradiation was employed to locally disrupt the orientation of the gold nanorods,resulting in depolarization within the irradiated regions.These areas displayed non-polarized fluorescence,while the non-irradiated regions retained both emission and fluorescence polarization characteristics.Localized imprinting was employed to modulate material thickness,thereby controlling the density of gold nanorods.Thinner regions exhibited weaker transverse localized surface plasmon resonance absorption,while thicker regions showed stronger absorption,enabling the coexistence of blue–green fluorescence and polarization patterns.Local humidification effectively reduced phosphorescence intensity,enhancing the material's environmental responsiveness.The composite demonstrated excellent reversibility over multiple stretching–selfhealing cycles and pattern-switching processes,highlighting its strong potential for multidimensional optical encryption and intelligent anticounterfeiting applications.
文摘The yellow peach moth, Conogethes punctiferalis （Guenee）, a multivoltine species that overwinters as diapausing larvae, is one of the most serious insect pests on maize in China. Effect of photoperiod and temperature on larval diapause was examined under empirical laboratory conditions. Short-day treatments caused larval diapause at 25℃, and the critical photoperiod was between 12 and 13 h （or 12 h 51 min） light per day. No sensitive instar was identified for diapause induction under alternated short- （L ： D 11 ： 13 h） and long-day （L ： D 14 ： 10 h） treatments at different larval stages. However, accumulative treatment of three instars and 10 d under short-day treatment was required for the induction of 50% larval diapause. All larvae entered diapause at 20℃, whereas less than 3% did so at 30℃, irrespective of the long- or short-day treatment. Furthermore, under the short-day treatment, more than 90% of larvae went into diapause with temperatures ≤ 25℃, but less than 17% did so at 28℃. In contrast, under the long-day treatment, less than 19% of larvae went into diapause with temperatures ≥23 ℃. The forward shift （5℃） of critical temperature under the long-day regime demonstrated the compensatory effect of temperature and photoperiod on diapause induction. In conclusion, C. punctiferalis had a temperature-dependent type Ⅰ photoperiodic diapause response; there was no sensitive instar for diapause determination, but the photoperiodic accumulation time countermeasures both of the short-day cycles and the number ofinstars exposed, and the photoperiodic diapause response, was a temperature-compensated phenomenon.
