The photosynthetic characteristics of strawberry (Fragariaananassa Duch. cv. Toyonoka)leaves under illumination of identical light intensity(55-57% natural light) withdifferent light quality were studied. It was showe...The photosynthetic characteristics of strawberry (Fragariaananassa Duch. cv. Toyonoka)leaves under illumination of identical light intensity(55-57% natural light) withdifferent light quality were studied. It was showed that the chlorophyll content,maximal photochemical efficiency of PSⅡ(Fv/Fm), Fm/Fo, amount of inactive PSⅡreactioncenters (Fi-Fo) and rate of QA reduction were positively correlated with the red-light/blue-light ratios, but the chlorophyll (a/b) ratios were negatively correlated withthem. Carotenoid content of the leaves was maximum under the blue film, than under greenfilm, red film, white film and yellow film, and negatively correlated with the red/far-red ratios. The apparent quantum yield (AQY), photorespiratory rate (Pr) and carboxylationefficiency (CE) were also strongly affected by light quality. The photosynthetic rate(Pn) in strawberry leaves under green film was significantly lower than under all otherfilm. Our results suggested that light quality is an essential factor regulating thedevelopment of PSⅡ, and phytochrome and an independent blue light photoreceptor,possibly a cryptochrome, can regulate photosynthetic performance.展开更多
Constructing blue thermally activated delayedfluorescence materials for high-performance organic light-emitting diodes(OLEDs)remains challenging due to the intrinsically strong intramolecular charge transfer nature of...Constructing blue thermally activated delayedfluorescence materials for high-performance organic light-emitting diodes(OLEDs)remains challenging due to the intrinsically strong intramolecular charge transfer nature of the nearly orthogonal connection of electron donor(D)and acceptor(A),which results in long-wavelength emission.Herein,an effective delayed-fluorescence design strategy of modulating D–A torsion angles is proposed and efficient sky-blue,pure-blue,and deep-blue delayed-fluorescence molecules consisting of a xanthenone acceptor and carbazole-based donors are created by decreasing the torsion angles.They exhibit strong delayed fluorescence with high photoluminescence quantum yields of 85–94%in doped films,and their delayed-fluorescence lifetimes are elongated from 1.0 to 27.6μs as the torsion angles decrease.These molecules can function as excellent emitters in OLEDs,providing efficient electroluminescence peaking at 442 nm(CIEx,y=0.15,0.08),462 nm(CIEx,y=0.15,0.18),and 482 nm(CIEx,y=0.17,0.30)with state-of-the-art external quantum efficiencies of up to 22.2%,33.7%,and 32.1%,respectively,demonstrating the proposed molecular design for efficient blue delayed-fluorescence molecules is successful and promising.展开更多
基金supported by the National Natura1 Science Foundation of China(39730340)
文摘The photosynthetic characteristics of strawberry (Fragariaananassa Duch. cv. Toyonoka)leaves under illumination of identical light intensity(55-57% natural light) withdifferent light quality were studied. It was showed that the chlorophyll content,maximal photochemical efficiency of PSⅡ(Fv/Fm), Fm/Fo, amount of inactive PSⅡreactioncenters (Fi-Fo) and rate of QA reduction were positively correlated with the red-light/blue-light ratios, but the chlorophyll (a/b) ratios were negatively correlated withthem. Carotenoid content of the leaves was maximum under the blue film, than under greenfilm, red film, white film and yellow film, and negatively correlated with the red/far-red ratios. The apparent quantum yield (AQY), photorespiratory rate (Pr) and carboxylationefficiency (CE) were also strongly affected by light quality. The photosynthetic rate(Pn) in strawberry leaves under green film was significantly lower than under all otherfilm. Our results suggested that light quality is an essential factor regulating thedevelopment of PSⅡ, and phytochrome and an independent blue light photoreceptor,possibly a cryptochrome, can regulate photosynthetic performance.
基金This study is financially supported by the National Natural Science Foundation of China(grant no.21788102)the Natural Science Foundation of Guangdong Province(grant no.2019B030301003)the State Key Lab of Luminescent Materials and Devices,South China University of Technology。
文摘Constructing blue thermally activated delayedfluorescence materials for high-performance organic light-emitting diodes(OLEDs)remains challenging due to the intrinsically strong intramolecular charge transfer nature of the nearly orthogonal connection of electron donor(D)and acceptor(A),which results in long-wavelength emission.Herein,an effective delayed-fluorescence design strategy of modulating D–A torsion angles is proposed and efficient sky-blue,pure-blue,and deep-blue delayed-fluorescence molecules consisting of a xanthenone acceptor and carbazole-based donors are created by decreasing the torsion angles.They exhibit strong delayed fluorescence with high photoluminescence quantum yields of 85–94%in doped films,and their delayed-fluorescence lifetimes are elongated from 1.0 to 27.6μs as the torsion angles decrease.These molecules can function as excellent emitters in OLEDs,providing efficient electroluminescence peaking at 442 nm(CIEx,y=0.15,0.08),462 nm(CIEx,y=0.15,0.18),and 482 nm(CIEx,y=0.17,0.30)with state-of-the-art external quantum efficiencies of up to 22.2%,33.7%,and 32.1%,respectively,demonstrating the proposed molecular design for efficient blue delayed-fluorescence molecules is successful and promising.
